Vaporizer and semiconductor processing apparatus

A vaporizer includes a vaporizing chamber configured to vaporize a liquid material and thereby form a gas material. A spray portion is configured to spray the liquid material in the vaporizing chamber. A delivery part is configured to deliver the gas material from the vaporizing chamber to a gas outlet. A heating portion is configured to heat the vaporizer. The delivery part includes a filter member covering the gas outlet and configured to allow the gas material to pass therethrough. A shield plate is disposed to cover the filter member on a side farther from the gas outlet.

TECHNICAL FIELD

The present invention relates to a vaporizer for vaporizing a liquid material to generate a gas material, and a semiconductor processing apparatus employing a vaporizer. The term “semiconductor process” used herein includes various kinds of processes which are performed to manufacture a semiconductor device or a structure having wiring layers, electrodes, and the like to be connected to a semiconductor device, on a target substrate, such as a semiconductor wafer or a glass substrate used for an LCD (liquid crystal display) or FPD (flat panel display), by forming semiconductor layers, insulating layers, and conductive layers in predetermined patterns on the target substrate.

BACKGROUND ART

As exemplary techniques for forming thin films of semiconductor devices, CVD (chemical vapor deposition) methods are known. Where a capacitor is fabricated in a process of manufacturing a semiconductor device, it is required to form a dielectric thin film with a high dielectric constant and a low leakage current, which facilitates high integration of the device. In order to achieve this, a film formation technique employing an organic metal material as a source material is used to form the dielectric thin film.

In such a film formation technique, an organic metal material used as a source material is normally in a liquid state or liquefied by a suitable solvent. The source material is turned into mist and vaporized in a vaporizer (source material vaporizer), and is then supplied into the reaction chamber of a film formation apparatus. In the vaporizer, the organic metal material needs to be sufficiently vaporized at a temperature that does not cause decomposition of the material. However, in practice, non-vaporized residual mist may be generated, and/or decomposition products of the organic metal material may be generated as particles. Accordingly, a problem arises in that the mist and particles degrade the quality of a thin film formed within the reaction chamber.

In light of this problem, conventionally, such a vaporizer is known that includes a filter disposed at the outlet to remove mist and particles (for example, see Jpn. Pat. Appln. KOKAI Publications No. 7-94426 and No. 8-186103 and U.S. Pat. No. 6,210,485). Further, such a vaporizer is known that includes a vaporizing plate disposed at an angle perpendicular to or interfering with the flow path of a gas material, and a heater disposed in the vaporizing plate to promote vaporization (for example, see Pat. Appln. KOKAI Publication No. 6-310444).

Furthermore, such a vaporizer is known that includes a vaporizing surface disposed at a position opposite the spray direction of a source material within a vaporizing chamber and configured to be controlled in temperature independently of the other inner surface portions of the vaporizing chamber (for example, see Pat. Appln. KOKAI Publication No. 2002-110546, and particularly a structure shown in FIGS. 7 and 8 thereof). The vaporizing surface is set at a temperature higher than that of the other inner surface portions. In this respect, conventionally, when a source material is intensively sprayed on an inner surface portion opposite the spray direction of the source material, non-vaporized residuals may be generated due to a temperature decrease of the inner surface portion. In contrast, the improved vaporizer described above can reduce such non-vaporized residuals and thereby increase the vaporization rate.

However, in the conventional gas material supply system described above, a filter may be clogged with mist and particles. In this case, the conductance is decreased in a short time, and the pressure inside a vaporizer is thereby increased. This decreases the gas material feed rate and vaporization efficiency at the vaporizer. Accordingly, in order to maintain the gas material feed rate and vaporization efficiency, the filter requires frequent cleaning or replacement, which in return decreases the operation rate of the apparatus.

According to a conventional system employing the vaporizing plate with a heater disposed therein described above, the vaporizing plate needs to widely expand in a gas passage to increase the trapping rate of mist. In this case, the vaporization efficiency at a vaporizer is decreased. Further, it can be hardly expected that particles are trapped by the vaporizing plate.

Further, according to a conventional vaporizer with the vaporizing surface independently controllable in temperature described above, the temperature of an inner surface portion opposite the spray direction of a source material is independently controlled. With this arrangement, the vaporization efficiency of the source material is increased within a vaporizing chamber. However, this arrangement can hardly work on the mist out of contact with the vaporizing surface. Accordingly, when non-vaporized residuals and particles do not come into contact with the vaporizing surface, but flow directly to the outlet or gas lead-out port of the vaporizing chamber, they can be discharged as they are.

DISCLOSURE OF INVENTION

An object of the present invention is to provide a vaporizer that can decrease mist and particles in a gas material.

In the process of developing the present invention, the inventors studied vaporizers of this kind. As a result, the inventors have arrived at the findings given below.

Specifically, a vaporizer can be arranged to have a first vaporizing region to vaporize and generate a gas material, and a pathway for the gas material to flow thereafter (a second vaporizing region), in which a filter member is disposed and heated to a temperature substantially the same as the heating temperature of the first vaporizing region. With this arrangement, residual mist contained in the gas material is not only trapped, but also re-vaporized. Since residual mist and particles contained in the gas material are trapped, the purity of the gas material to be supplied is increased. Further, the trapped residual mist is re-vaporized by the heated filter member, so the filter member is less clogged. Consequently, the vaporization efficiency at the vaporizer is maintained for a long time period, and the pressure inside the vaporizer is prevented from increasing. Accordingly, maintenance operations can be less frequent, and thus the operation rate of the apparatus is improved.

Incidentally, as a manner of heating a filter member, there may be a case where heating means is disposed outside the filter member to heat the filter member from outside, or a case where heating means is disposed inside the filter member to heat the filter member from inside. In the former case, the filter member is heated by radiation heat and conduction heat. In this case, there is a difficulty in uniformly heating the filter member, because the heating means should not be disposed within the flow path of a gas material. If the temperature of the filter member is less uniform, trapped residual mist is heated less uniformly, and the filter member may be locally clogged. For example, a filter member may be attached at the peripheral portion thereof, which is heated to a relatively high temperature that does not cause decomposition of a source material. In this case, the central portion of the filter member comes into contact with gas and/or mist and is cooled to a lower temperature. Thus the filter member cannot vaporize mist, but is clogged therewith.

According to a first aspect of the present invention, there is provided a structure for supplying a gas material, comprising: a first vaporizing region configured to vaporize a source material; and a second vaporizing region provided in a pathway of the gas material vaporized by the first vaporizing region, wherein the second vaporizing region comprises an air permeable filter member disposed in the pathway, and a heat transfer portion disposed in thermal contact with the filter member at a position other than a peripheral portion to transfer heat generated by heating means.

According to the first aspect, the source material is once vaporized by the first vaporizing region, and residual mist contained in the gas material is then re-vaporized by the second vaporizing region, so the mist in the gas material is reduced. Further, heat generated by the heating means is transferred by the heat transfer portion to the filter member at a position other than the peripheral portion, so the temperature of the filter member can be uniform, thereby vaporizing mist uniformly or over a larger area on the filter member. Further, the source material is prevented from being locally concentrated and deposited on the filter member, and thus the filter member can be less clogged. In this case, the vaporization efficiency of the vaporizer is prevented from decreasing, and the pressure inside the first vaporizing region is prevented from increasing, so the vaporizer can be continuously operated for a very long time. Further, maintenance operations, such as cleaning and replacement, can be simplified. Furthermore, mist and particles generated in the first vaporizing region are trapped by the filter member, and thus a process using the gas material can be performed with high quality.

For example, the filter member may be formed of a porous structure, a plate structure having a number of fine holes, a structure consisting of packed fibers, or a mesh structure.

A plurality of heat transfer portions are preferably disposed in thermal contact with the filter member at a plurality of positions. With this arrangement, the temperature of the filter member can be more uniform. It is preferable that the heat transfer portions are in thermal contact with the filter member at positions essentially uniformly distributed over the cross section of the pathway (an imaginary plane perpendicular to the flow direction of the gas material). The filter member is preferably heated also at the peripheral portion.

The heat transfer portion may be formed of a projection disposed on the heating means or a member containing the heating means and protruding toward the filter member; an independent member interposed between the heating means or a member containing the heating means and the filter member; or a projection disposed on the filter member protruding toward the heating means or a member containing the heating means. Further, fixing means, such as setscrews, is preferably used to fix at least two of the heating means or a member containing the heating means, the heat transfer portion, and the filter member, to each other.

In this case, temperature control is preferably performed on the basis of the temperature of the heat transfer portion or filter member. Where the temperature of the heat transfer portion or filter member, which receives heat from the heating means, is used to perform temperature control, the temperature of the filter member is improved in controllability. For example, the temperature detection point of a temperature sensor may be disposed in the heat transfer portion or filter member, so that a temperature control circuit or the like can control heating means on the basis of the output of the temperature sensor. Further, the heat transfer portion or filter member may be provided with heating means other than that for the chamber. In this case, it is preferable that the temperature of the heat transfer portion or filter member is controlled by this heating means to be the same as the temperature of the chamber.

According to a second aspect of the present invention, there is provided a structure for supplying a gas material, comprising: a first vaporizing region configured to vaporize a source material; and a second vaporizing region provided in a pathway of the gas material vaporized by the first vaporizing region, wherein the second vaporizing region comprises an air permeable filter member disposed in the pathway, and heating means disposed in the filter member.

According to the second aspect, the heating means is disposed in the filter member, so that the filter member is efficiently heated and becomes less uneven in temperature. The filter member can trap mist and solid substances, and uniformly vaporize residual mist deposited thereon. Consequently, the filter member is prevented from being clogged or generating particles due to residual mist locally deposited thereon.

In the first and second aspects, the first vaporizing region may be formed of a conventionally known vaporizer. This vaporizer may comprise a vaporizing chamber with a heated inner surface, and spray means configured to spray the source material within the vaporizing chamber. Further, the second vaporizing region may be formed of a line filter connected downstream from the vaporizer. The supply structure for a gas material may be arranged such that the first vaporizing region and second vaporizing region are formed in a single vaporizer.

According to a third aspect of the present invention, there is provided a reaction processing apparatus (semiconductor processing apparatus), comprising: a supply structure for a gas material according to any one of the structures described above, and a reaction chamber configured to cause a reaction of the gas material supplied by the supply structure. With this arrangement, the amount of mist and particles, such as solid substances, is reduced in the gas material supplied by the supply structure, so the process quality of the reaction chamber is improved. This reaction processing apparatus widely encompasses various processing apparatuses, which perform a reaction of the gas material within the reaction chamber using energy of a heat source or the like, such as a semiconductor film formation apparatus of the vapor phase growth type, a liquid crystal device film formation apparatus of the vapor phase growth type, a compound semiconductor film formation apparatus of the vapor phase growth type, and a vapor phase etching apparatus. Particularly, in the case of a film formation apparatus of the vapor phase growth type (CVD apparatus), a thin film with high quality can be formed very effectively.

According to a fourth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein the delivery part comprises an air permeable filter member, and a heat transfer member configured to transfer heat of the heating portion to the filter member.

According to the fourth aspect, residual mist is re-vaporized and solid substances are trapped in the delivery part of the vaporizer. Consequently, it is possible to reduce the amount of mist and solid substances contained in the gas material to be supplied. The heat transfer portion transfers heat from heating means to the filter member at a position other than the peripheral portion, so the filter member becomes less uneven in temperature. Consequently, the filter member provides more uniform re-vaporization effect, and is prevented from suffering local deposition of the source material (or being clogged). Further, mist and particles generated in the vaporizing chamber are trapped, and thus a process using the gas material can be performed with high quality.

In this case, temperature control is preferably performed on the basis of the temperature of the heat transfer portion or filter member. Where the temperature of the heat transfer portion or filter member, which receives heat from the heating means, is used to perform temperature control, the temperature of the filter member is improved in controllability. For example, the temperature detection point of a temperature sensor may be disposed in the heat transfer portion or filter member, so that a temperature control circuit or the like can control heating means on the basis of the output of the temperature sensor. Further, the heat transfer portion or filter member may be provided with heating means other than that for the chamber. In this case, it is preferable that the temperature of the heat transfer portion or filter member is controlled by this heating means to be the same as the temperature of the chamber.

A plurality of heat transfer portions are preferably disposed in thermal contact with the filter member at a plurality of positions. With this arrangement, the temperature of the filter member can be more uniform. It is preferable that the heat transfer portions are in thermal contact with the filter member at positions essentially uniformly distributed over the cross section of the delivery part (a plane perpendicular to the direction from the vaporizing chamber to the delivery part).

According to a fifth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein the delivery part comprises an air permeable filter member, and heating means disposed in the filter member.

In the fifth aspect, a shield plate is preferably disposed between the interior of the vaporizing chamber and the filter member. The shield plate prevents mist entering from the vaporizing chamber into the delivery part from directly coming into contact with filter member. Consequently, the amount of such residual mist can be reduced that is not vaporized within the vaporizing chamber but directly passes through the delivery part without change. In this case, it is possible to solve a problem in that mist is deposited on the filter member without being vaporized there while the mist draws a large amount heat from the filter member and thereby locally decreases the temperature thereof.

The filter member is preferably detachable by detaching or disassembling only the delivery part. With this arrangement, there is no need to entirely disassemble the other components of the vaporizer, such as the spray means and vaporizing chamber, when detaching and attaching operations are performed for the filter member by detaching or disassembling the delivery part. Consequently, maintenance operations, such as cleaning or replacement, can be easily performed for the filter member.

According to a sixth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein the vaporizer comprises a shield plate disposed at a position facing the vaporizing chamber to cover the delivery part while ensuring a communication clearance, and a heat transfer portion disposed in thermal contact with the shield plate to transfer heat generated by heating means.

According to the sixth aspect, the shield plate is disposed at a position facing the vaporizing chamber to cover the delivery part, so that residual mist and particles not vaporized within the vaporizing chamber are prevented from directly reaching the delivery part. Consequently, the residual mist and particles reaching a source material feed line can be reduced. Further, heat of the heating means is transferred to the shield plate through the heat transfer portion, so the heated shield plate itself can provide a vaporizing effect. Consequently, the vaporization efficiency is improved by the shield plate that can vaporize residual mist. A gas material vaporized by the vaporizing chamber and shield plate flows through the communication clearance into an internal space of the delivery part, and is then delivered to a source material feed line.

In this case, the heat transfer portion is preferably disposed in thermal contact with the shield plate at a position other than the peripheral portion. With this arrangement, the temperature of the shield plate can be more uniform. Further, temperature control means is preferably disposed to perform temperature control on the basis of the temperature of the heat transfer portion or shield plate.

According to a seventh aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein the vaporizer comprises a shield plate disposed at a position facing the vaporizing chamber to cover the delivery part while ensuring a communication clearance, and heating means disposed in the shield plate.

According to the seventh aspect, the shield plate is disposed at a position facing the vaporizing chamber to cover the delivery part, so that residual mist and particles not vaporized within the vaporizing chamber are prevented from directly reaching the delivery part. Consequently, the residual mist and particles reaching a source material feed line can be reduced. Further, the heating means is disposed in the shield plate, so the heated shield plate itself can provide a vaporizing effect. Consequently, the vaporization efficiency is improved by the shield plate that can vaporize residual mist. A gas material vaporized by the vaporizing chamber and shield plate flows through the communication clearance into an internal space of the delivery part, and is then delivered to a source material feed line.

According to an eighth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber having a vaporizing surface configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; heating means configured to heat the vaporizing surface of the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein a shield plate is disposed to face the vaporizing chamber independently of the vaporizing surface and cover the delivery part while ensuring a communication clearance from the vaporizing chamber to the delivery part, the shield plate is configured to be head by the heating means or heating means other than the heating means, and a set temperature of the shield plate is the same as a set temperature of the vaporizing surface.

According to the eighth aspect, the shield plate is heated at the same temperature as the vaporizing surface, so that the shield plate can vaporize mist. Consequently, the shield plate can improve the vaporization efficiency while preventing residual mist and solid substances from entering the delivery part.

In this case, the delivery part is preferably provided with a plurality of heat transfer columns distributed therein and in thermal contact with an inner surface of the delivery part and the shield plate. In this case, residual mist passing through the communication clearance into the delivery part can be trapped and vaporized by the plurality of heat transfer columns that are distributed in the delivery part and in thermal contact with an inner surface thereof and the shield plate. Consequently, it is possible to further improve the vaporization efficiency while reducing particles.

The shield plate is preferably configured to prevent mist from traveling straight on from the vaporizing chamber through the communication clearance into the delivery part. With this arrangement, mist and solid substances passing through the communication clearance into the delivery part are prevented from flowing out downstream. Particularly, when mist enters the delivery part, it comes into contact with the inner surface of the delivery part and is vaporized there, so the vaporization efficiency is further increased.

According to a ninth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein a filter member is disposed in the delivery part, and a shield plate is disposed at a position facing the vaporizing chamber to cover the filter member while ensuring a communication clearance.

According to the ninth aspect, the filter member is disposed in the delivery part, and the shield plate is disposed at a position facing the vaporizing chamber to cover the filter member. With this arrangement, residual mist and particles are prevented from directly reaching the filter member, and the filter member can be less clogged. Consequently, the heated shield plate can vaporize residual mist, so that the vaporization efficiency is increased, while maintenance operations can be simplified.

According to a tenth aspect of the present invention, there is provided a vaporizer comprising: a vaporizing chamber having a vaporizing surface configured to vaporize a source material; spray means configured to spray the source material within the vaporizing chamber; heating means configured to heat the vaporizing surface of the vaporizing chamber; and a delivery part opened to the vaporizing chamber and configured to deliver the gas material to a source material feed line, wherein a filter member is disposed in the delivery part, a shield plate is disposed on a side of the filter member closer to the vaporizing chamber to face the vaporizing chamber independently of the vaporizing surface and cover the filter member while ensuring a communication clearance from the vaporizing chamber to the delivery part, the filter member and the shield plate are configured to be head by the heating means or heating means other than the heating means, and a set temperature of the filter member and the shield plate is the same as a set temperature of the vaporizing surface.

According to the tenth aspect, the filter member and the shield plate is heated at the same temperature as the vaporizing surface, so that the filter member and the shield plate can vaporize mist. Consequently, the filter member and the shield plate can improve the vaporization efficiency while preventing residual mist and solid substances from entering the delivery part, and reducing the amount of residual mist reaching the filter member by the shield plate.

The shield plate is preferably configured such that, where imaginary straight lines extend from the vaporizing chamber to the communication clearance, no imaginary straight lines can reach the filter member. With this arrangement, such residual mist is reduced that enters the delivery part from the vaporizing chamber through the communication clearance, and directly passes through the filter member. Consequently, the filter member is further prevented from being clogged, and particularly prevented from suffering local concentration of deposit.

An inter-space is preferably formed between the filter member and the shield plate to expand all over the filter member and allow the gas material to pass therethrough. With this arrangement, the gas material entering the delivery part through the communication clearance can pass over the entirety of the filter member, so the conductance for the gas material is ensured. Further, mist and solid substances are prevented from being intensively trapped on a local portion of the filter member, and thus the filter member can be less clogged. In this case, the inter-space between the filter member and shield plate is preferably set to have a distance within a range of 1 to 100 mm, more preferably within a range of 1 to 10 mm, and most preferably at about 5 mm.

The shield plate is preferably disposed to cover the entirety of the filter member, viewing from the vaporizing chamber. With this arrangement, mist and solid substances entering from the vaporizing chamber are prevented from directly reaching the filter member. Particularly, the shield plate is preferably configured to expand outward all around from the peripheral portion of the filter member.

The peripheral portion of the filter member is preferably fixed to the inner surface of the delivery part.

The communication clearance is preferably formed to allow the vaporizing chamber to communicate with the filter member all around the shield plate. With this arrangement, the gas material can flow smoothly through communication clearance to the filter member, while mist and solid substances are being more uniformly trapped on the filter member. In this case, the distance described above is preferably set to be within a range of 0.5 to 10 mm, more preferably to be 10 mm or less, and most preferably at about 2 mm.

The communication clearance is preferably formed around the shield plate. In this case, the shield plate can have a simple structure, and the maintenance operations, such as cleaning of the shield plate and portions near the communication clearance, become simpler. The opening width of the communication clearance (the distance between the shield plate and the inner surface of the delivery part around it) is preferably set to be within a range of 0.5 to 10 mm, and preferably to be not less than 1 mm, and most preferably set at about 2 mm.

The flow path of the gas material from the vaporizing chamber to the delivery part includes a first flow path portion defined by the opening width of the communication clearance, and a second flow path portion defined by the gap between the filter member and shield plate to communicate with the first flow path portion. In this case, the path portions are preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion. Where the filter member is fixed at the peripheral portion, the flow path of the gas material further includes a third flow path portion defined by the gap between the shield plate and the peripheral portion of the filter member and formed to allow the first and second flow path portions to communicate with each other. In this case, the third flow path portion is preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion.

The filter member is preferably formed of a plate body having a number of fine holes penetrating therethrough in the flow direction of the gas material. As described above, where the filter member is formed of a simple plate body, heating means can be easily embedded in the filter member. Further, the filter member can have a higher thermal conductivity, so the temperature distribution of the filter member is more uniform. The fine holes preferably have a shape with a penetration distance larger than the opening diameter, e.g. with a diameter of about 0.01 to 1.0 mm, and a penetration distance of about 5 to 15 mm, to ensure the trapping rate of residual mist.

According to an eleventh aspect of the present invention, there is provided a reaction processing apparatus comprising a vaporizer according to any one of the structures described above, and a reaction chamber configured to cause a reaction of the gas material supplied from the vaporizer. With this arrangement, the amount of mist and particles is reduced in the gas material supplied by the vaporizer, so the process quality of the reaction chamber is improved. This reaction processing apparatus widely encompasses various semiconductor processing apparatuses, which perform a reaction of the gas material within the reaction chamber in a certain manner, e.g., adding heat energy, such as a semiconductor film formation apparatus of the vapor phase growth type, a liquid crystal device film formation apparatus of the vapor phase growth type, a compound semiconductor film formation apparatus of the vapor phase growth type, and a vapor phase etching apparatus. Particularly, in the case of a film formation apparatus of the vapor phase growth type (CVD apparatus), this aspect is effectively.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described hereinafter with reference to the accompanying drawings. In the following description, the constituent elements having substantially the same function and arrangement are denoted by the same reference numerals, and a repetitive description will be made only when necessary.

FIRST EMBODIMENT

FIG. 1is a schematic sectional view showing the structure of a vaporizer according to a first embodiment of the present invention. This vaporizer100includes a vaporizing chamber110that defines a vaporizing surface110B and a vaporizing space110A both correspond to a first vaporizing region. Spray means120is disposed to spray a liquid material within the vaporizing space110A. A delivery part130corresponding to a second vaporizing region is detachably attached to the vaporizing chamber110. A detection pipe139is disposed for a pressure gauge (capacitance manometer: not shown) to be connected thereto, so as to detect the pressure inside the vaporizing space110A. A filter member139xis attached at a port of the vaporizing chamber110connected to the pipe139. The filter member139xprevents mist and substances from entering the pressure gauge. The filter member139xis closely fixed to the port rim by an attachment member139y.

The vaporizing chamber110has a casing wall111, and heating means112, such as heater, embedded in the casing wall111. The casing wall111has a port111afor the spray means120to be connected thereto. The spray means120includes a source material supply pipe121for supplying a source material or liquid material, which consists of an organic metal source material, or which has been prepared by dissolving an organic metal source material in a solvent. The spray means120further includes a spray gas supply pipe122for supplying a spray gas, such as argon gas, (Ar, or, e.g., Ne or N2), and a spray nozzle123for spraying the source material as mist. The spray nozzle123is configured to spray the source material (liquid, such as an organic metal material) and spray gas from individual fine ports, so as to atomize the material.

The delivery part130is configured to deliver the gas material vaporized in the vaporizing space110A to a feed line141. The delivery part130includes a sidewall131, which is recessed on a side facing the vaporizing space110A to form an internal space131SO. Columnar heat transfer portions protrude within the internal space131SO. Heating means132such as a heater is embedded in the sidewall131(in reception holes131ainFIG. 2). The internal space131SO of the delivery part130communicates with the vaporizing space110A and feed line141. The delivery part130can be disposed on any side of the vaporizing space110A, as long as it faces the vaporizing space110A.

A filter member133is disposed inside the internal space131SO to cover a delivery port (gas outlet)131A connected to the feed line141. The filter member133may be formed of an air permeable filter plate. For example, the filter member may be formed of a porous material, a filter plate with a number of fine holes, a material consisting of packed fibers, or a mesh material. More specifically, the filter material may be a non-woven or sintered body formed of packed metal fibers (for example, stainless steel fibers), which can withstand a high temperature (for example, it is within a range of about 180° C. to 350° C. and suitably set in accordance with the evaporation temperature and decomposition temperature of the source material). For example, the metal fibers have a diameter of about 0.1 to 3.0 mm. Particularly, it is preferable to use a sintered material prepared by sintering granular bodies, such as spherical bodies, having a high thermal conductivity. The granular bodies may be made of a material selected from the group consisting of non-metal materials, such as a ceramic and quartz; stainless steel; nonferrous metal materials, such as aluminum, titanium, and nickel; and alloys of these materials. These matters concerning the structure and material of the filter member are common to the following embodiments.

FIG. 2Ais an inner side view showing the delivery part130, viewing from the vaporizing space110A. The filter member133is in contact with the sidewall131and connected and fixed thereto at the peripheral portion, to completely cover the opening section of the internal space131SO. Specifically, the peripheral portion of the filter member133is fixed to the sidewall131by setscrews138or the like. Heat transfer portions135and137protrude inward from the sidewall131at positions separate from the peripheral portion of the filter member133. The heat transfer portions135and137provide thermal contact of the filter member133with the sidewall131. The heat transfer portions135and137also serve as support members for supporting the filter member133. The heat transfer portions135and137are made of a metal (such as stainless steel) having a high thermal conductivity. Each of the heat transfer portions135is a column with an elliptical cross-section. Each of the heat transfer portions137is a column with a circular cross-section. In this embodiment, the heat transfer portions135and137are heated by the heating means, such as a heater, embedded in the sidewall131. However, the heat transfer portions may be formed of heating means, or provided with heating means embedded therein.

A shield plate134is disposed at a side of the filter member133facing the vaporizing space110A. The shield plate134is made of a thermally conductive metal material, such as stainless steel. The shield plate134faces the vaporizing space110A to prevent source material mist sprayed by the spray nozzle123from directly coming into contact with the filter member133. With this arrangement, the temperature decrease of the filter member133is suppressed to reliably vaporize mist thereon, so the filter member133is prevented from being clogged. The shield plate134is disposed to cover the filter member133essentially in plane. An inter-space (or gas passage)130D is formed between the shield plate134and filter member133to expand all over the filter member133and allow the vaporized source material to diffuse or pass therethrough. The inter-space130D is heated by the shield plate134and filter member133being heated by the heat transfer portions135and137.

A communication clearance134bis formed around the shield plate134for the vaporizing space110A and internal space131SO to communicate with each other, so as to efficiently send the vaporized source material therethrough. An opening134ais formed in the shield plate134on a side near the spray nozzle123. The opening134aincreases the area of the communication clearance, so that the gas material can easily flow from the vaporizing space110A to the internal space131SO behind the filter member133. The opening134ais formed here, because the spray nozzle123has an essentially limited spray angle range, with which the mist sprayed by the spray nozzle123can hardly reach the delivery part130directly.

FIGS. 2B,2C, and2D are inner side views respectively showing modifications of the shield plate.FIG. 2Bshows a shield plate134′ provided with opening134a′ continuously or entirely extending all around over the filter member133.FIG. 2Cshows a shield plate134″ provided with a plurality of openings134a″ separately formed therein all around the filter member133. The shield plate may be provided with slit-like openings (including a case where they are concentrically formed).

FIG. 2Dshows a shield plate134X provided with no openings formed therein, and thus covering the entirety of the filter member133. In this case, the communication clearance134baround the shield plate (seeFIGS. 1 and 2A) is formed to provide a sufficient communication between the vaporizing space110A and internal space131SO. Where the shield plate134X entirely covers the filter member133, as shown inFIG. 2D, it is advantageous to prevent residual mist of the source material from being directly deposited on the filter member133.

The shield plate134and filter member133with spacers136interpose therebetween, are fixed together to the heat transfer portions135. The spacers136are made of a material having a high thermal conductivity, such as a metal, e.g., Al or stainless steel, or a ceramic. Setscrews136aare used as fixing means for fixing the shield plate134and spacers136to the heat transfer portions135. The same fixing means are also used for fixing the filter member133to the heat transfer portions137. The filter member133and shield plate134are set in thermal contact with the heating means132through the heat transfer portions135and spacers to receive heat generated by the heating means132. The filter member133and shield plate134are also heated by radiation heat received from the inner surface of the casing wall111of the vaporizing chamber110that faces the vaporizing space110A.

In this embodiment, the source material is supplied through the source material supply pipe121and sprayed from the spray nozzle123into the vaporizing space110A. Part of the mist of the source material thus sprayed is vaporized while flying, and other part arrives at the inner surface of the casing wall111heated by the heating means112, and is heated and vaporized thereon. In order to vaporize the source material, the vaporizing chamber110, particularly the inner surface of the casing wall111, is heated by the heating means112to a temperature within a range from a value lower than the decomposition temperature of the source material to a value higher than the evaporation temperature of the source material. This temperature is set to be within a range of, e.g., about 100 to 350° C.

The gas material thus generated in the vaporizing space110A passes through the filter member133from around the shield plate134and enters the internal space131SO. When the gas material flows to the internal space131SO, it contains fine residual mist that has not being vaporized in the vaporizing space110A. The residual mist is trapped by the filter member133, and is heated and re-vaporized by heat transferred to the filter member133from the heating means132through the heat transfer portions135and137. The filter member133is preferably heated to a temperature within substantially the same range as that of the vaporizing chamber.

The heat transfer portions135and137are preferably disposed with essentially uniform distribution over the entire cross section of the filter member133across the flow path of the gas material. With this arrangement, the filter member133can be more uniformly heated to improve the vaporization efficiency of the residual mist, and thereby allow the filter member to be less clogged.

In the example shown in the figure, the peripheral portion of the filter member is in contact with (connected and fixed to) the inner surface of the delivery part, and receives heat from the inner surface. The heat transfer portions may be provided with heating means to heat the filter member.

The shield plate134prevents the mist sprayed by the spray nozzle123from directly reaching the filter member133. In this case, it is possible to solve such a problem that effective vaporization of deposited mist is locally deteriorated at certain portions of the filter member133due to heat loss caused by excess mist. Consequently, the shield plate134prevents the filter member133from being clogged at these portions, which may reduce the delivery amount of gas material and increase the pressure inside the vaporizing chamber.

In the embodiment described above, the delivery part130is arranged such that the sidewall131is detachable from the casing wall111to easily pick up the filter member133. Accordingly, if there is a problem with the filter member133, such as clogging, the filter member133can be easily and swiftly detached for cleaning or replacement with new one. With this arrangement, the maintenance operation time is shorter, which improves the operation rate and process yield of the apparatus.

In this embodiment, the shield plate134is heated by heat transferred through the heat transfer portions135and137. Accordingly, when the source material mist within the vaporizing chamber110A comes into direct contact with the shield plate134, the mist is vaporized also on the surface of the shield plate134. However, when the mist is vaporized on the shield plate134, the vaporization heat thereof decreases the temperature of the shield plate134. This decrease in the temperature of the shield plate134changes with change in the amount of mist coming into contact with shield plate134, which depends on the amount of sprayed liquid material. In general, the temperature of the shield plate134becomes about 5 to 15° C. lower than the set temperature of the vaporizing chamber110.

The filter member133is only required to be disposed close to the shield plate134on the side facing the delivery passage. For example, typically, the inter-space130D between the filter member133and shield plate134is set to have a distance within a range of 1 to 100 mm, preferably within a range of 1 to 50 mm, and more preferably within a range of 2 to 10 mm. Typically, the distance is most preferably set at about 5 mm. If the distance is smaller than that within the range, the conductance for the gas material is too low, and the substantial range of the filter member133for residual mist to be deposited thereon becomes too narrow. In this case, solid substances may be intensively deposited on a specific portion of the filter member133. As the distance is larger, the conductance for the gas material is increased and local deposition of solid substances on the filter member133is thereby suppressed, but the size of the vaporizer needs to be increased.

The communication clearance134b, or distance between the peripheral portion of the shield plate134and the sidewall131around the edge portion, has an opening width which is preferably set to be within a range of 0.5 to 10 mm, and more preferably to be not less than 1 mm, to ensure the conductance for the gas material. However, if the opening width is too large, mist is more likely to directly reach the filter member133. Accordingly, the opening width is most preferably set at about 2 mm.

The distance between the peripheral portion of the shield plate134and the peripheral portion of the filter member133on the internal space131SO side (the flow path width in the internal space131SO) is preferably set to be within a range of 0.5 to 100 mm, and more preferably within a range of 0.5 to 10 mm. The distance is most preferably set at about 2 mm. As the distance is smaller, the conductance for the gas material is decreased. Conversely, as the distance is larger, mist entering through the communication clearance130B is more likely to directly reach the filter member133.

The flow path of the gas material from the vaporizing chamber110A to the delivery part130includes a first flow path portion defined by the opening width of the communication clearance134b, and a second flow path portion defined by the gap between the filter member133and shield plate134to communicate with the first flow path portion. In this case, the path portions are preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion. Where the filter member133is fixed at the peripheral portion, the flow path of the gas material further includes a third flow path portion defined by the gap between the shield plate134and filter member133and formed to allow the first and second flow path portions to communicate with each other. In this case, the third flow path portion is preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion.

SECOND EMBODIMENT

FIGS. 3A and 3Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a second embodiment of the present invention.FIGS. 3A and 3Bshow a delivery part150usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the second embodiment are the same as those of the first embodiment.

In this embodiment, the delivery part150includes a sidewall151, which is recessed on a side facing the vaporizing space to form an internal space150A. Heat transfer portions155and157protrude from the sidewall151within the internal space150A. Heating means152the same as that described above is embedded in the sidewall151(in reception holes151a). The internal space150A communicates with a delivery passage150S. A filter member153the same as that described above is disposed within the internal space150A. The filter member153is thermal contact with the heat transfer portions155and157protruding from the inner surface of the sidewall151, as in the first embodiment. Each of the heat transfer portions155is a column with an elongated cross-section, such as an elliptical cross-section. Each of the heat transfer portions157is a column with a circular cross-section. Each of these columnar portions can have any shape as long as it can make face contact with the filter member153and shield plate154to easily transfer heat. For example, the sectional shape of each columnar portion may be rhombic, triangle, star-shaped, rectangle, or circular. The peripheral portion of the filter member153is fixed to the sidewall151by setscrews158or the like. The number and position of the heat transfer portions155and157are set to uniformly transfer heat to the filter member153.

A shield plate154is attached and fixed to the heat transfer portions155and157by setscrews156a, with spacers156interposed therebetween. An inter-space150D is formed between the shield plate154and filter member153to expand all over the filter member153. The shield plate154is disposed on the delivery part150to face the vaporizing chamber. The shield plate154is circular in the plan view. The shield plate154is disposed to cover the filter member153entirely in plane. A communication clearance150Bb is formed of an annular gap between the peripheral portion of the shield plate154and the sidewall151around the shield plate154. As described above, the shield plate154covers the filter member153entirely in plane, so that the mist source material cannot directly come into contact with the filter member153to prevent the filter member153from being clogged and suffering local concentration of deposit. Consequently, pressure increase inside the vaporizing chamber is suppressed and the filter service life is prolonged, while residual mist and particles are prevented from being delivered downstream.

The respective portions described above are configured basically the same as those of the first embodiment. Accordingly, the filter member153is arranged to receive not only heat of the heating means152directly from the sidewall151at the peripheral portion, but also heat of the heating means152through the heat transfer portions155and157disposed in thermal contact with portions other than the peripheral portion. The shield plate154is heated by the filter member153and the heat transfer portions155and157through the spacers156.

In this embodiment, the gas material vaporized in the vaporizing chamber passes through the communication clearance150B into the inter-space150D of the delivery part150. Then, the gas material passes through the filter member153and is delivered from the interior space150A into a feed line150S.

The communication clearance150B is configured such that, where imaginary straight lines extend from the vaporizing chamber to the communication clearance150B, no imaginary straight lines can directly reach the filter member153. In other words, even if residual mist within the vaporizing chamber enters the delivery part150through a straight flight route, the residual mist cannot be directly deposited onto the filter member153. Further, the mist source material cannot come into direct contact with the filter member153. Specifically, the opening width of the communication clearance150B in the radial direction is set to prevent any linear flight route passing through the communication clearance150B from reaching the filter portion of the filter member153.

The parameters of the respective portions of the delivery part150are the same as those of the first embodiment. For example, the opening width of the communication clearance150B in the radial direction is set at 2 mm, the distance between the shield plate154and the peripheral portion of the filter member153in the axial direction is set at 2 mm, the distance between the shield plate154and the filter portion of the filter member153in the axial direction is set at 5 mm, the width of the peripheral portion of the filter member153in the radial direction is set at 4 mm, and the distance between the outer edge position of the shield plate154and the substantial outer edge position of the filter member153(i.e., the outer edge position of the filter portion) in the radial direction is set at 2 mm. With this arrangement, the amount of deposit on the filter member153can be reduced to prevent the filter member153from being clogged and suffering concentration of deposit. Particularly, concentration of deposit on the peripheral portion of the filter member153can be suppressed.

In this embodiment, a temperature sensor (for example, thermocouple)159is inserted in a hole151bformed in the sidewall151, and the detection point thereof is disposed in the heat transfer portion155having an elongated shape in the plan view. With this arrangement, the temperature of the heat transfer portions155, i.e., a temperature at a position very close to the filter member153can be detected. The output of the temperature sensor159is connected to, e.g., a temperature control circuit CONT, which is configured to control the heating means152on the basis of the output of the temperature sensor159. This temperature is preferably controlled on the basis of the output of the temperature sensor159, to be the same temperature as the other heating means of the vaporizer (the heating means of the vaporizing chamber). The heating means152may be controlled independently of the other heating means112of the vaporizing chamber such that the heat transfer portions155, filter member153, and casing wall111have the same temperature. With this arrangement, the temperature of the filter member153and shield plate154can be precisely controlled. Consequently, the filter member153is prevented from being clogged, and the pressure increase inside the vaporizing chamber is suppressed. Further, the residual mist and particles can be reduced.

In this embodiment, the temperature of the heat transfer portions155is detected to control the heating means152, so the temperature controllability of the filter member153and shield plate154is improved as compared to the first embodiment. Thus the temperature decrease of the shield plate154is suppressed, as compared with the first embodiment. In this case, the set temperature of the heating means152is preferably set to be the same as the set temperature of the vaporizing chamber.

The filter member153is only required to be disposed close to the shield plate154on the side facing the delivery passage150S. For example, typically, the distance between the filter member153and shield plate154is set to be within a range of 1 to 100 mm, preferably within a range of 1 to 50 mm, and more preferably within a range of 2 to 10 mm. Typically, the distance is most preferably set at about 5 mm. If the distance is smaller than that within the range, the conductance for the gas material is too low, and the substantial range of the filter member153for residual mist to be deposited thereon becomes too narrow. In this case, solid substances may be intensively deposited on a specific portion of the filter member153. As the distance is larger, the conductance for the gas material is increased and local deposition of solid substances on the filter member153is thereby suppressed, but the size of the vaporizer needs to increase. These matters are common to the respective embodiments described later.

The communication clearance150B, or distance between the peripheral portion of the shield plate154and the sidewall151around the edge portion, has an opening width which is preferably set to be within a range of 0.5 to 10 mm, and more preferably to be not less than 1 mm, to ensure the conductance for the gas material. However, if the opening width is too large, mist is more likely to directly reach the filter member153. Accordingly, the opening width is most preferably set at about 2 mm. These matters are common to the respective embodiments described later.

The distance between the peripheral portion of the shield plate154and the peripheral portion of the filter member153on the internal space150A side (the flow path width in the internal space150A) is preferably set to be within a range of 0.5 to 100 mm, and more preferably within a range of 0.5 to 10 mm. The distance is most preferably set at about 2 mm. As the distance is smaller, the conductance for the gas material is decreased. Conversely, as the distance is larger, mist entering through the communication clearance150B is more likely to directly reach the filter member153. These matters are common to the respective embodiments described later.

The flow path of the gas material from the vaporizing chamber to the delivery part150includes a first flow path portion defined by the opening width of the communication clearance150B, and a second flow path portion (the inter-space150D) defined by the gap between the filter member153and shield plate154to communicate with the first flow path portion. In this case, the path portions are preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion. Where the filter member153is fixed at the peripheral portion, the flow path of the gas material further includes a third flow path portion defined by the gap between the shield plate154and filter member153to allow the first and second flow path portions to communicate with each other. In this case, the third flow path portion is preferably configured such that mist and solid substances entering through the first flow path portion are prevented from traveling straight on to the second flow path portion. These matters are common to the respective embodiments described later.

THIRD EMBODIMENT

FIGS. 4A and 4Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a third embodiment of the present invention.FIGS. 4A and 4Bshow a delivery part150′ usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the third embodiment are the same as those of the first embodiment. Portions of the delivery part150′ the same as those of the second embodiment are denoted by the same reference numerals.

In this embodiment, the sidewall151′ is provided with an exhaust passage150C separately from a delivery passage150S. The delivery passage150S is formed to make an internal space150A communicate with a feed line connected to a reaction processing apparatus, while the exhaust passage150C is formed to make the internal space150A communicate with the outside (for example, the exhaust line of the reaction processing apparatus). This exhaust passage150C is disposed at a position most remote from the spray nozzle, e.g., at the lowest position inFIGS. 4A and 4B. The exhaust passage150C is connected to an exhaust line, such as a bypass line (evacuation line) bypassing the reaction processing section of the reaction processing apparatus described later, to exhaust gas. The exhaust passage150C is used for a gas material not to be supplied into the reaction processing section but to be exhausted, until the supply conditions of the gas material are stabilized.

In this embodiment, a filter member153′ has an opening153a′ at a position facing the exhaust passage150C. The rim of the opening153a′ is formed as part of the peripheral portion of the filter member153′, so that it is connected to the exhaust passage150C without a gap by setscrews158′ for fixing the filter member153′.

In this embodiment, the gas material flows around the shield plate154into the internal space150A through a communication clearance150B. Then, the gas is directly exhausted through the opening153a′ and exhaust passage150C, when a valve V2provided on an exhaust line connected to the exhaust passage150C is opened. At this time, a valve V1provided on a feed line connected to the delivery passage150S is closed. Accordingly, the gas material does not pass through the filter member153′ when it is not supplied to the reaction processing section, so the service life of the filter member153′ is prolonged.

When the gas material is supplied into the feed line, the valve V2provided on the exhaust line connected to the exhaust passage150C is closed, while the valve V1provided on the feed line is opened. Consequently, the gas material having been directed to the exhaust passage150C is switched to flow through the filter member153′ into the delivery passage150S and feed line.

FOURTH EMBODIMENT

FIGS. 5A and 5Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a fourth embodiment of the present invention.FIGS. 5A and 5Bshow a delivery part150″ usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the fourth embodiment are the same as those of the first embodiment. Portions of the delivery part150″ the same as those of the second embodiment are denoted by the same reference numerals.

In this embodiment, heating means152″ is embedded in a sidewall151″ (in reception holes151a″) such that the distal end thereof is in contact with each of heat transfer portions157″. The heat transfer portions157″ protrude within the internal space150A and come into thermal contact with a filter member153and a shield plate154, as in the previous embodiments. The heating means152″ comprises, e.g., rod-like heaters directly connected to the heat transfer portions157″, so that the filter member153and shield plate154can be efficiently heated through the heat transfer portions157″.

Also in this embodiment, heat transfer portions155″ each having an elongated shape in the plan view are disposed as in the embodiments described above. The heat transfer portions157″ extend from the sidewall151″ into some of the heat transfer portions155″ and protrude within the internal space150A. Specifically, each of the heat transfer portions155″ is disposed to include a heat transfer portions157″.

In this embodiment, the heat transfer portions157″ are respectively provided with threaded holes at their distal ends. The filter member153, spacers156, and shield plate154are stacked in this order at the distal ends of the heat transfer portions157″. In this state, setscrews156aare screwed into the threaded holes to fix the filter member153and shield plate154to the heat transfer portions157″.

FIG. 5Cis a view showing a modification of the heating means152″ and a part connected thereto. The heating means152S″ shown inFIG. 5Cis formed of a rod-like heater with a screw embedded in the distal end. A nut152T″ to engage with the screw is prepared in place of the spacer156, and a setscrews152U″ to engage with the nut152T″ is further prepared. The filter member153is disposed between the heating means152S″ and a set of nuts152T″, and the shield plate154is disposed between the nuts152T″ and a set of setscrews152U″. In this state, the setscrews152U″ are fixed to the heating means152S″ by the nuts152T″.

In this embodiment, the heat transfer portions157are formed of part of the heating means152″. With this arrangement, the filter member153and shield plate154are more efficiently heated. Consequently, the temperature decrease of the shield plate154is suppressed. In this case, the set temperature of the heating means152″ is preferably set to be the same as the set temperature of the vaporizing chamber.

FIFTH EMBODIMENT

FIGS. 6A and 6Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a fifth embodiment of the present invention.FIGS. 6Aand6B show a delivery part160usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the fifth embodiment are the same as those of the first embodiment.

The delivery part160includes a sidewall161and heating means162embedded in the sidewall161(in reception holes161a). A shield plate164is closely fixed to the sidewall161from inside (from the side facing the vaporizing chamber). An internal space160A is defined between the sidewall161and shield plate164and communicates with a delivery passage160S. The peripheral portion of a filter member163is fixed by setscrews168or the like within the internal space160A. At positions other than the peripheral portion, the filter member163is in thermal contact with a plurality of heat transfer portions165and167, which protrude from the inner surface of the sidewall161. The filter member163and shield plate164are disposed with spacers166interposed therebetween, and fixed to the heat transfer portions165and167by setscrews166a. An inter-space160D is formed between the filter member163and shield plate164to expand all over the filter member163. A vaporized gas flows through the space between the filter member163and shield plate164, and passes through the filter163into the delivery passage160S.

Each of the heat transfer portions165has an elongated shape in the plan view, and contains therein the temperature detection point of a temperature sensor169, as in some of the embodiments described above.

The shield plate164is provided with a plurality of communication openings164A, which look like slits in the plan view. The communication openings164A are bent (inflected or curved) in the thickness direction of the shield plate164to prevent residual mist entering from the vaporizing chamber from directly reaching the filter member163. In other words, the communication openings164A are configured such that, where imaginary straight lines extend from the vaporizing chamber to the communication openings164A, no imaginary straight lines can directly reach the filter member163. With this arrangement, essentially all residual mist comes into contact with the shield plate164at least once, and then enters the internal space160A. Consequently, it is possible to promote the effect of vaporizing the residual mist by the shield plate while ensuring flow of the gas material, so as to prevent the filter member163from being clogged and suffering concentration of deposit. A plurality of communication openings164A may be arrayed in parallel or concentrically with each other in the plane of the shield plate164.

As described above, the shield plate is provided with the communication openings. The communication openings are only required to allow no imaginary straight lines to directly reach the filter member from the vaporizing chamber through the communication openings. Accordingly, in place of the bent shape described above, the communication openings may be through holes formed in the shield plate to be oriented not in directions toward the filter member but in directions deviating from the filter member, to attain the same effect described above.

SIXTH EMBODIMENT

FIGS. 7A and 7Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a sixth embodiment of the present invention.FIGS. 7A and 7Bshow a delivery part160′ usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the sixth embodiment are the same as those of the first embodiment. Portions of the delivery part160′ the same as those of the fifth embodiment are denoted by the same reference numerals.

This embodiment includes a shield plate164′ with communication openings164A′ formed therein. The communication openings164A′ are formed at positions outside the region overlapping a filter member163in the plan view, i.e., around the filter member163. With this arrangement, where imaginary straight lines extend from the vaporizing chamber to the communication openings164A′, no imaginary straight lines can directly reach the filter member163. In the example shown in the figure, the communication openings164A′ are arc slits. A plurality of communication openings164A′ may be arrayed concentrically at regular intervals. Alternatively, a plurality of communication openings164A′ may be arrayed in a staggered pattern (alternate pattern). As in the previous embodiment, heating means162is controlled on the basis of the output of a temperature sensor169to control the temperature of the shield plate164′.

In this embodiment, heating means164H′ formed of, e.g., a wire heater is inserted in the shield plate164′ to directly heat the shield plate164′. The heating means164H′ extends in the shield plate164′ in a meandering shape. In the example shown in the figure, the heating means164H′ is introduced into the shield plate164′ from outside, but the heating means164H′ may be embedded in the shield plate164′. Alternatively, the heating means164H′ may be formed of linear parts disposed in a lattice or spiral shape. Further, the heating means164H′ may be formed of a plurality of parts inserted into the shield plate164′.

The shield plate164′ is also provided with the temperature detection point of a temperature sensor164TC′ therein. The heating means164H′ is controlled by a temperature control circuit CONT, on the basis of temperature detected by the temperature sensor164TC′, to directly and independently control the temperature of the shield plate164′. With this arrangement, the temperature of the shield plate164′ can be precisely adjusted to an optimum temperature, so as to stabilize vaporization of mist by the shield plate164′. In this case, the set temperature of the heating means164H′ is preferably set to be the same as the set temperature of the vaporizing chamber.

As described above, heating means is disposed in the shield plate, so as to improve controllability of the temperature of the shield plate. Consequently, the source material can be vaporized more efficiently, and the residual mist and particles can be reduced.

SEVENTH EMBODIMENT

FIGS. 8A and 8Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a seventh embodiment of the present invention.FIGS. 8A and 8Bshow a delivery part150X usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the seventh embodiment are the same as those of the first embodiment. Portions of the delivery part150X the same as those of the second embodiment are denoted by the same reference numerals.

This embodiment has the same basic structure as that of the second embodiment, but differs in that the number of heat transfer columns is larger. The heat transfer columns are formed of heat transfer portions155and157, spacers156, and setscrews156a, as in the second embodiment, and distributed within an internal space150A. The heat transfer columns are in thermal contact with a filter member153X and a shield plate154X, as in the second embodiment. Further, the heat transfer columns are in thermal contact with the inner surface of a sidewall151X along with the shield plate154X.

In this embodiment, a larger number of heat transfer columns are distributed on the delivery part, so residual mist flowing with the gas material from the vaporizing chamber through a communication clearance150B can more easily come into contact with the heat transfer columns. The residual mist is heated by the heat transfer columns and vaporized into gas, and thus the vaporization efficiency is improved.

EIGHTH EMBODIMENT

FIGS. 9A and 9Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to an eighth embodiment of the present invention.FIGS. 9A and 9Bshow a delivery part150Y usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the eighth embodiment are the same as those of the first embodiment. Portions of the delivery part150Y the same as those of the second embodiment are denoted by the same reference numerals.

In this embodiment, a plurality of columnar heat transfer portions157Y are formed on a sidewall151Y, and a shield plate154Y is fixed to the heat transfer portions157Y by setscrews156a. In this embodiment, no filter member is disposed, but, in place thereof, a number of heat transfer columns formed of the heat transfer portions157Y are distributed between the inner surface of the sidewall151Y and the shield plate154Y. In this case, the heat transfer columns serve as a filter to trap and re-vaporize residual mist and particles entering from a communication clearance150B into an internal space150A.

Specifically, the shield plate154Y is disposed to cover a delivery port (gas outlet)150SO connected to a delivery passage150S, and a gas passage (to further vaporize the source material) is formed between the shield plate154Y and delivery passage150S and connects the vaporizing chamber110(seeFIG. 1) to the delivery port150SO. In this gas passage, the heat transfer columns or heat transfer portions157Y serve as a fluid baffle alternative to a filter member. If necessary a filter member may be further added to this structure.

Also in this embodiment, the heat transfer portions157Y are arrayed to prevent residual mist entering through the communication clearance150B from directly flowing out of the delivery passage150S. Specifically, the heat transfer portions157Y are configured such that, where imaginary straight lines extend from the communication clearance150B into the internal space150A, all of them can reach the heat transfer portions157Y. Particularly, a plurality of heat transfer portions157Y are arrayed in a direction essentially perpendicular to the flow direction of a source material gas, so that no imaginary straight lines can extend, without passing through the heat transfer portions157Y, from the periphery of the internal space150A near the communication clearance150B to the inner annular surface of the delivery passage150S. For example, the heat transfer portions157Y are arrayed in a staggered pattern.

NINTH EMBODIMENT

FIGS. 10A and 10Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a ninth embodiment of the present invention.FIGS. 10A and 10Bshow a delivery part150Z usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the ninth embodiment are the same as those of the first embodiment. Portions of the delivery part150Z the same as those of the second embodiment are denoted by the same reference numerals.

In this embodiment, a heat transfer frame157Z is attached and fixed to a sidewall151Z from inside (from the side facing the vaporizing chamber). The heat transfer frame157Z has an outer frame portion directly in thermal contact with the sidewall151Z and a plurality of beam portions157Za extending inward from the outer frame portion. A filter member153Z is fixed at the peripheral portion to the outer frame portion. The filter member153Z is in thermal contact with the beam portions157Za at positions other than the peripheral portion. A shield plate154Z is fixed via spacers156to the filter member153Z by setscrews156a. In this embodiment, the filter member153Z and shield plate154Z are connected to each other by the beam portions157Za, spacers156, and setscrews156a, at positions other than the peripheral portion.

The inner surface of the sidewall151Z and the beam portions157Za face each other with a gap interposed therebetween. With this arrangement, after a gas material flows through the communication clearance150B into the internal space150A, and passes through the filter member153Z, it is delivered into a feed line without being interfered with the beam portions157Za.

Heating means157H is inserted in the heat transfer frame157Z at the beam portions157Za. In the example shown in the figure, the wire heating means157H extends in a meandering shape to pass through a plurality of beam portions157Za in order. As a matter of course, the heating means157H may be formed of a plurality of parts inserted into the respective beam portions157Za or embedded in the respective beam portions157Za.

The temperature detection point of a temperature sensor157TC is disposed in the heat transfer frame157Z, particularly in the beam portions157Za. The heating amount of the heating means157H is controlled by a temperature control circuit CONT, on the basis of temperature detected by the temperature sensor157TC. With this arrangement, the temperature of the heat transfer frame157Z can be adjusted independently of the sidewall151Z. As described above, the temperature of the heat transfer portions157Za is detected by the temperature sensor157TC to control the heating means157H. Accordingly, the temperature controllability of the shield plate154Z is improved, and the temperature of the shield plate154Z is less decreased. In this case, the set temperature of the heating means157H is preferably set to be the same as the set temperature of the vaporizing chamber.

In this embodiment, each of the beam portions157Za may be formed of heating means, such a rod-like heater, as a whole. Heating means may be disposed in the outer frame portion of the heat transfer frame157.

As described above, the heat transfer portions may be formed of beams, the heat transfer portions may be provided with heating means therein, or the heat transfer portions may be formed of heating means as a whole.

TENTH EMBODIMENT

FIGS. 11A and 11Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a tenth embodiment of the present invention.FIGS. 11A and 11Bshow a delivery part170usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the tenth embodiment are the same as those of the first embodiment.

This delivery part170has a structure in which a plate member172having a heating function is fitted in a sidewall171from inside. The plate member172has an inner end surface172afacing the vaporizing chamber, and thereby provides the same function as the shield plate described above. The inner end surface172ais separated from the sidewall171around it with a gap that serves as a communication clearance170B. On the reverse side from the inner end surface172a, the plate member172includes a plurality of columnar heat transfer portions172pfacing the sidewall171. The heat transfer portions172pare in thermal contact with the inner surface of the sidewall171.

A heating portion172H, such as a heater, and a temperature detecting portion, such as a temperature sensor172TC, are embedded in the plate member172. A part of the plate member172protrudes outside through the sidewall171, at which electric feed terminals172econnected to the heating portion172H and a detection terminal172fof the temperature sensor172TC are disposed. The delivery part170has an internal space170A defined by a region surrounded by the sidewall171and plate member, and connected to a delivery passage170S. The internal space170A has an annular shape (like a ring).

A number of heat transfer portions172pare distributed in the internal space170A to be perpendicular to the flow direction of a source material gas. The heat transfer portions172pserve as a filter to trap residual mist and particles entering from the vaporizing chamber. The heat transfer portions172p, i.e., heat transfer columns, are in thermal contact with the inner surface of the sidewall171as well as the portion defining the inner end surface172aof the plate member172, which provides the same function as the shield plate. With this arrangement, residual mist comes into contact with the heat transfer portions172pand vaporized, so the vaporization efficiency is improved and generation of particles is suppressed. An annular filter member may be disposed in the internal space170A, so as to remove residual mist and solid substances, such as particles.

The surface of the plate member172facing the vaporizing chamber110(seeFIG. 1) serves as a vaporizing surface for vaporizing the liquid material as the other inner surface of the vaporizing chamber110does. Further, the plate member172covers a delivery port (gas outlet)170SO connected to the delivery passage170S, such that a gas passage is formed between the plate member172and delivery passage170S to allow the vaporizing chamber110and delivery port170SO to communicate with each other. In this gas passage, the heat transfer columns or heat transfer portions172pserves as a fluid baffle alternative to a filter member.

Also in this embodiment, the heat transfer portions172pare configured such that, where imaginary straight lines extend from the vaporizing chamber through the communication clearance170B, no imaginary straight lines can directly reach the delivery passage170S without passing through the heat transfer portions172p. Particularly, a plurality of heat transfer portions172pare arrayed such that no imaginary straight lines can extend, without passing through the heat transfer portions172p, from positions of the internal space170A (the periphery thereof inFIGS. 11A and 11B) near the communication clearance170B to the delivery passage170S (the inner annular surface thereof). With this arrangement, essentially all residual mist comes into contact with the heat transfer portions172pat least once, and then enters the delivery passage170S. Consequently, it is possible to promote the effect of vaporizing the residual mist while ensuring flow of the gas material and preventing delivery of particles. Further, since no filter member is used, the vaporizing chamber can be free from pressure increase due to clogging, and can have a long service life.

The temperature control of the plate member172is performed by a temperature control circuit CONT, on the basis of temperature detected by the temperature sensor172TC, independently of the temperature control of the vaporizing chamber. Consequently, the temperature decrease of the inner end surface172aserving as a shield plate is suppressed. In this case, the set temperature of the plate member172is preferably set to be the same as the set temperature of heating means for the vaporizing chamber. Other heating means may be embedded in the sidewall171.

ELEVENTH EMBODIMENT

FIGS. 12A and 12Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to an eleventh embodiment of the present invention.FIGS. 12A and 12Bshow a delivery part170′ usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the eleventh embodiment are the same as those of the first embodiment. Portions of the delivery part170′ the same as those of the tenth embodiment are denoted by the same reference numerals.

This embodiment has a structure in which a plate member172′ is fitted in a sidewall171′ from inside. The plate member172′ has an inner end surface172aseparated from the sidewall171′ around it to form a communication clearance170B′. An internal space170A′ is defined between the sidewall171′ and plate member172′, and connected to a delivery passage170S′. The internal space170A has an annular shape (like a ring).

In this embodiment, an annular filter member173is disposed inside the internal space170A′. The peripheral portion of the filter member173is fixed to the inner surface of the sidewall171′. At positions other than the peripheral portion, the filter member173is in thermal contact with columnar heat transfer portions171p′ protruding from the sidewall171′ and columnar heat transfer portions172p′ protruding from the plate member172′. The filter member173is sandwiched between the heat transfer portions171p′ and172p′.

In this embodiment, other heating means172″ is also embedded in the sidewall171′ (in reception holes171a′). The filter member173is arranged to receive heat from both of the heating portion172H of the plate member172′ and the heating means172″ through the heat transfer portions171p′ and172p′. Accordingly, the filter member173can receive a large amount of heat through the heat transfer portions. With this arrangement, the vaporization efficiency can be increased, while the filter member removes residual mist and solid substances, such as particles.

TWELFTH EMBODIMENT

FIGS. 13A and 13Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a twelfth embodiment of the present invention.FIGS. 13A and 13Bshow a delivery part180usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the twelfth embodiment are the same as those of the first embodiment.

In this embodiment, heating means182is formed of a plurality of parts inserted into a sidewall181from outside, and attached thereto. The distal ends of the heating means182are respectively connected to columnar heat transfer portions185protruding from the inner surface of the sidewall181.

An internal space180A is defined within the sidewall181and communicates with a delivery passage180S. A filter member183like a container is disposed inside the internal space180A and is opened inward (facing the vaporizing chamber). The peripheral portion of the filter member183is fixed to the inner surface of the sidewall181by setscrews188or the like. At positions other than the peripheral portion, the filter member183is in thermal contact with columnar support projections181cprotruding from the sidewall181and the heat transfer portions185.

A shield plate184is disposed at a position of the internal space180A facing the vaporizing chamber (inner side from the filter member183). The shield plate184is in thermal contact with the filter member183through spacers186, and is fixed to the heat transfer portions185by setscrews186a.

The shield plate184is separated from the sidewall181around it with a gap that serves as a communication clearance180B.

In this embodiment, the filter member183has a shape like a container with a depth extending in the axial direction. Consequently, the filter member183has a side portion extending in the axial direction, which increases the filtering area, and thereby prolong the service life of the filter member183. The heat transfer columns or heat transfer portions185, spacers186, and setscrews186aare directly in thermal contact with the heating means182. Consequently, the filter member183and shield plate184can be efficiently heated.

THIRTEENTH EMBODIMENT

FIGS. 14A and 14Bare a schematic inner side view and a schematic sectional side view, respectively, showing the main structure of a vaporizer according to a thirteenth embodiment of the present invention.FIGS. 14A and 14Bshow a delivery part190usable in place of the delivery part130of the vaporizer shown inFIG. 1. The other portions of the thirteenth embodiment are the same as those of the first embodiment.

In this embodiment, heating means192is embedded in a sidewall191(in reception holes191a). An internal space190A opened inward (facing the vaporizing chamber) is formed in the sidewall191and communicates with a delivery passage190S.

A filter member193is disposed inside the internal space190A, and fixed to the sidewall191by setscrews198or the like at the peripheral portion. At positions other than the peripheral portion, the filter member193is in thermal contact with a plurality of columnar heat transfer portions197, which protrude from the inner surface of the sidewall191. A shield plate194facing the vaporizing chamber is disposed on the inner side of the filter member193with spacers196interposed therebetween, and is fixed to the heat transfer portions197by setscrews196a. The shield plate194is separated from the sidewall191around it with a gap that serves as a communication clearance190B. An inter-space190D is formed between the shield plate194and filter member193to expand all over the filter member193.

The sidewall191has a hole191bformed therein, and a temperature sensor199is inserted in the hole191b. The temperature detection point of the temperature sensor199is positioned near or inside one of the heat transfer portions197.

In this embodiment, heating means193H is disposed in the filter member193. Specifically, the heating means193H is formed of a wire heater, which extends through the filter member193in a meandering shape. A temperature sensor193TC is also disposed in the filter member193. The heating amount of the heating means197H is controlled by a temperature control circuit CONT, on the basis of temperature detected by the temperature sensor193TC, so that the temperature of the filter member193is directly and independently controlled.

In this embodiment, the heating means193H is disposed in the filter member193, so that the filter member193is directly heated and the temperature of the filter member193is directly and independently controlled. With this arrangement, the temperature of the filter member193can be precisely controlled, and the uniformity in the temperature can be improved. Consequently, the filter member193is prevented from being clogged and suffering local concentration of deposit, the pressure increase inside the vaporizing chamber is suppressed, and the service life of the filter is prolonged.

FOURTEENTH EMBODIMENT

FIG. 15is a schematic sectional side view showing a vaporizer according to a fourteenth embodiment of the present invention.FIG. 16is a sectional plan view showing the vaporizer according to the fourteenth embodiment, taken along the line A-A inFIG. 15. The vaporizer according to this embodiment has a vaporizing chamber210forming a vaporizing surface210B and a vaporizing space210A, as in the first embodiment. A spray means120is disposed to spray a liquid material within the vaporizing space210A. A delivery part220serving as a second vaporizing region is detachably attached to the vaporizing chamber210. The structure of the spray means120(a source material supply pipe121, a spray gas supply pipe122, and a spray nozzle123), the sidewall211, and heating means212of the vaporizing chamber210are the same as those of the first embodiment. The delivery part220includes a sidewall221, heating means222, a filter member223, a shield plate224, heat transfer portions225, spacers226, and setscrews226a, which have the same functions as those of the first embodiment. An internal space220A formed in the delivery part220, a communication clearance220B formed around the shield plate224, and a delivery passage220S are arranged in the same manners as those of the first embodiment.

As shown inFIG. 16, in this embodiment, the vaporizing chamber210has an inner surface shape which is curved about the axial line of the spray nozzle123. Specifically, the vaporizing chamber210is cylindrical. The vaporizing chamber210may be conical about the axial line of the spray nozzle123, or spherical with a diameter corresponding to the axial line of the spray nozzle123. The filter member223and shield plate224have a curved shape extending along the inner surface that is curved about the axial line of the spray nozzle123, as described above. The peripheral portion of the filter member223is fixed to the sidewall221by setscrews228or the like. An inter-space220D is formed between the filter member223and shield plate224.

As described above, in this embodiment, the shield plate224has a shape extending along the inner surface of the vaporizing chamber210. Consequently, a large filtering area is ensured, and the vaporizer is compact. Further, in this embodiment, the delivery part220is configured to hardly affect flows of the mist and gas material within the vaporizing chamber210. Specifically, in the example shown in the figure, the vaporizing chamber210has a shape (a revolution body shape) that essentially uniformly extends all around the axial line of the spray nozzle123. With this arrangement, the temperature distribution within the vaporizing chamber210, and the temperature distribution on the inner surface of the vaporizing surface210B and shield plate224can be stable. Consequently, solid substances are prevented from being intensively deposited on a specific portion. The filter member223has a planar shape extending along the shield plate224, so the distance between the filter member223and shield plate224is constant. In this case, it is possible to effectively use the entirety of the filter member223, so as to efficiently trap residual mist and solid substances.

In this embodiment, as described above, the vaporizing chamber210has an inner surface curved about the axial line of the spray nozzle123, but the shape of the vaporizing chamber is not limited to a specific one. The vaporizing chamber may have a polyhedral shape, such as a cubic (hexahedral) shape. In this case, the shield plate and/or filter member are preferably formed to have a shape defined by part of a polyhedral shape, which extends along the inner surface of the vaporizing chamber, as described above. In this case, the shield plate and/or filter member may form two or more sides of the polyhedral shape. Further, the vaporizing chamber may have an inner surface formed of a combination of a curved surface and a flat surface.

In this embodiment, as in the first embodiment, a port connected to a detection pipe219for attaching a pressure gauge (not shown) is formed to face the vaporizing chamber210A. This port is provided with a filter member213and a shield plate214disposed on the side of the filter member213facing the vaporizing chamber210A. The filter member213is in contact with heat transfer portions215protruding from the inner surface of the sidewall211. The shield plate214is fixed to the heat transfer portions215by setscrews216awith spacers216interposed therebetween, and is in thermal contact with the heat transfer portions215through the spacers216and setscrews216a. A clearance is formed between the shield plate214and sidewall211to allow the vaporizing chamber210A to communicate with a space containing the filter member213. Further, this clearance communicates with the inside of the detection pipe219through the filter member213.

The shield plate214prevents residual mist and solid substances entering from the vaporizing chamber210A from easily reaching the filter member213. Consequently, the filter member213can be less clogged, and the service life of the filter member213is thereby prolonged. At positions other than the peripheral portion, the filter member213and shield plate214are in thermal contact with the sidewall211through the heat transfer portions215. These members are heated as in the inner surface of the vaporizing chamber210A, and residual mist deposited thereon is thereby vaporized.

FIFTEENTH EMBODIMENT

FIG. 17Ais a schematic sectional side view showing a vaporizer according to a fifteenth embodiment of the present invention. The portions of the fifteenth embodiment other than a delivery part230are the same as those of the first embodiment. The delivery part230includes a sidewall231, a honeycomb filter member232disposed between the sidewall231and vaporizing space110A, and heating means233, such as a heater embedded in the filter member232. A gas material delivery passage231ais connected to the sidewall231to deliver a gas material into a feed line. Heating means for heating the sidewall231may be separately disposed to prevent a gas having passed through the filter member232from decreasing the temperature. This heating means may be disposed inside the sidewall231or on the outer surface thereof.

The filter member232is a plate made of a metal having a good thermal conductivity (for example, stainless steel), or a ceramic, such as AlN or SiC. The filter member232has a reception through hole (or reception hole, hereinafter)232aformed therein and extending in a direction across (“perpendicular to” in the example shown in the figure) the flow direction of the gas material (in the direction toward right in the figure). The heating means233is inserted in the reception hole232a. The heating means233may be configured to be present over the entirety inside the filter member232. In this case, the thermal efficiency is further improved. The filter member232further has a number of fine holes232bpenetrating therethrough in a direction essentially parallel with the flow direction of the gas material. The fine holes232bmay be formed essentially perpendicular to the flow direction of the gas material, so that residual mist and solid substances come into contact with the filter member and are re-vaporized thereon.

The fine holes232bhave a shape with a penetration distance (length) larger than the diameter. The length of the fine holes232b(which is the same as the thickness of the filter member232in the example shown in the figure) is designed to sufficiently increase the trapping rate of fine residual mist generated in the vaporizing space110A. Specifically, the fine holes232bhave a diameter of about 0.01 to 1.0 mm, and a penetration distance of about 5 to 15 mm.

Some of the fine holes232bmay be directed across the reception hole232afor the heating means233. Alternatively, part of the fine holes232bmay be omitted at the position intersecting with the reception hole232a.

SIXTEENTH EMBODIMENT

FIG. 17Bis a schematic sectional side view showing a vaporizer according to a sixteenth embodiment of the present invention. In the sixteenth embodiment, a filter member234is disposed between a sidewall231and a honeycomb filter member232. The filter member234is connected and fixed to the sidewall231by fixing members235. An inter-space230D is formed between the filter member232and filter member234to expand all over these filters. The portions of the sixteenth embodiment other than the filter member232and heating means233are the same as those of the fifteenth embodiment shown inFIG. 17A.

In this structure, the filter member234disposed downstream from the honeycomb filter member232provides the effect of further reducing mist and particles delivered to a feed line. The filter member234is preferably configured to trap finer residual mist than the filter member232does. For example, the filter member234may be the same as the filter member133of the first embodiment. In the example shown in the figure, the filter member234is heated through the sidewall231, or indirectly heated by radiation heat from the filter member232. The filter member234is supplied with heat from heating means through heat transfer portions235(spacers), as in the filter member133shown inFIG. 1. The filter member234is fixed to the heat transfer portions235and sidewall231by fixing means235a. Heating means may be embedded in the filter member234, as in the filter member232of the fifteenth embodiment. Heating means may be embedded in the sidewall231. In any case, the filter member234is preferably controlled to be heated at the same temperature as the vaporizing surface (inner surface) of the vaporizing chamber.

In this embodiment, the filter member232traps and vaporizes relatively large residual mist, while the filter member234traps relatively small residual mist. Accordingly, the mist removing rate is improved, and the filter members232and234can be less clogged.

SEVENTEENTH EMBODIMENT

FIG. 18Ais a schematic sectional side view showing a vaporizer according to a seventeenth embodiment of the present invention. The portions of the seventeenth embodiment other than a delivery part330are the same as those of the first embodiment.

In this embodiment, the delivery part330includes an outer wall331and an inner wall332disposed on the inner side of the outer wall331and facing a vaporizing space110A. The outer wall331has a gas material delivery passage331aconnected thereto. The inner wall332has a communication hole332aconnecting the vaporizing space110A to an internal space330A of the delivery part330. A heating means333such as a heater is embedded in the heating means333.

The internal space330A is defined between the outer wall331and inner wall332. A filter member334is disposed within the internal space330A. At positions other than the peripheral portion, the filter member334is in thermal contact with the inner wall332through heat transfer portions335. The heat transfer portions335are configured to receive heat generated by the heating means333from the inner wall332and transfer heat to the filter member334at positions other than the peripheral portion. The filter member334is connected and fixed to the inner wall332through the heat transfer portions335. Specifically, the filter member334is fixed to the heat transfer portions335and inner wall332by fixing means335a. Thus, the heat transfer portions335also serve as support members for supporting the filter member334.

In this embodiment, the gas material is generated within the vaporizing space110A and enters the internal space330A through the communication hole332a. The gas material in the internal space330A passes through the filter member334and then is delivered from a gas material delivery passage331a. The filter member334is heated by the heating means333through the heat transfer portions335, so, when fine residual mist contained in the gas material is deposited thereon, the mist is reliably vaporized. In the example shown in the figure, at distributed positions other than the peripheral portion, the filter member334is in thermal contact with the plurality of heat transfer portions335. Consequently, the entire filter member334is uniformly heated, so that the filter member334becomes less uneven in temperature, and is prevented from being locally clogged. Also in this case, the filter member334is preferably controlled to be heated at the same temperature as the vaporizing surface (inner surface) of the vaporizing chamber.

In this embodiment, the inner wall332of the delivery part330faces the vaporizing space110A of the vaporizing chamber110. The inner wall332is provided with the heating means333embedded therein, so the heating means333contributes the effect of vaporizing the source material within the vaporizing space110A.

The communication hole332aformed in the inner wall332is positioned to be closer to the spray means (or spray nozzle (not shown)). With this arrangement, when mist is sprayed within vaporizing space110A, it is less possible that the mist directly flows through the communication hole332aand is trapped by the filter member334.

EIGHTEENTH EMBODIMENT

FIG. 18Ais a schematic sectional side view showing a vaporizer according to an eighteenth embodiment of the present invention. This embodiment includes a delivery part430, in which heating means432is embedded in a sidewall431. A filter member433is disposed on the inner side of the sidewall431. At positions other than the peripheral portion, the filter member433is in thermal contact with heat transfer portions434(spacers), which protrude from the sidewall431. The heat transfer portions434are connected and fixed to both of the filter member433and sidewall431. Specifically, the filter member433is fixed to the heat transfer portions434and sidewall431by fixing means434a. Thus, the heat transfer portions434also serve as support members for supporting the filter member433. Also in this case, the filter member434is preferably controlled to be heated at the same temperature as the vaporizing surface (inner surface) of the vaporizing chamber.

NINETEENTH EMBODIMENT

FIG. 19is a schematic sectional side view showing a vaporizer according to a nineteenth embodiment of the present invention. In this embodiment, the vaporizer500includes a source material vaporizing section510, spray means520, and a delivery part530. The source material vaporizing section510has a sidewall511, a vaporizing surface511A forming the inner surface of the sidewall511, and heating means512, such as a heater, embedded in the sidewall511. The spray means520has a source material supply pipe521, a spray gas supply pipe522, and a spray nozzle523.

The spray nozzle523is configured to spray the source material, using the pressure of the spray gas. The source material and spray gas are respectively supplied into the spray nozzle523, and the source material is sprayed from a plurality of (three in the example shown in the figure) spray ports523aalong with the spray gas. Specifically, the supplied source material is divided by a source material distribution cell523s into a plurality of source material supply passages523v. The source material supply passages523vcommunicate with the spray ports523a. The spray gas is divided by the spray gas distribution cell523tinto passages respectively disposed to be coaxial with the source material supply passages523v. The spray gas assists to spray the source material supplied through the respective source material supply passages523vfrom the spray ports523a. As described above, a plurality of spray ports523aare used to spray the source material, so as to increase the source material feed rate and thus the amount of mist. Further, even where the spray amount is increased, mist can be sprayed with a uniform diameter. Accordingly, the vaporization efficiency of the source material is improved, and the residual mist and particles are reduced.

In the example shown in the figure, only one source material supply pipe521is used to supply the source material into the spray nozzle523, but a plurality of source material supply pipes521may be used, as needed. In this case, source materials of different types may be supplied through a plurality of source material supply pipes521and mixed within the spray nozzle523immediately before being sprayed. This mixture can be then divided into a plurality of spray ports523aalong with the spray gas, and sprayed therefrom (matrix spray).

The vaporizing surface511A formed of the inner surface of the sidewall511is almost spherical (hemispherical) and disposed opposite the spray direction of the spray nozzle523. With this arrangement, the distance from the spray ports523ato the vaporizing surface511A is almost constant without reference to the mist spray direction. Consequently, the mist sprayed from the spray nozzle523can be efficiently vaporized because, e.g., the amount of mist sprayed onto the vaporizing surface511A or spherical surface is essentially uniform.

The delivery part530according to this embodiment has a sidewall531and a honeycomb filter member532disposed on the inner side thereof. The sidewall531has a gas material delivery passage531aformed therein. The filter member532has a reception through hole (or reception hole, hereinafter)532aformed therein and extending in a direction across the flow direction of the gas material. The reception hole532amay be formed essentially perpendicular to the flow direction of the gas material, so that residual mist and solid substances come into contact with the filter member and are re-vaporized thereon. Heating means533, such as a heater, is disposed on the peripheral side of the reception hole532a. The filter member532further has a number of fine holes532bpenetrating therethrough in the flow direction of the gas material. The fine holes532bconnect the vaporizing space510A to an internal space530A of the delivery part530.

In this embodiment, the filter member532is disposed on the side of the vaporizing space510A closer to the spray nozzle523. Specifically, the filter member532is disposed around the spray nozzle523to face the vaporizing surface511A. The internal space530A of the delivery part530is defined behind (back side) the spray nozzle523in the spray direction. Further, the gas material delivery passage531ais formed behind the internal space530A. With this arrangement, the mist sprayed from the spray nozzle523is prevented from being directly deposited on the filter member523. In this case, there is no need to use the shield plate134of the first embodiment.

The filter member532is essentially uniformly heated by the heating means533embedded therein. Accordingly, when fine residual mist contained in the gas material generated by the vaporizing surface511A within the vaporizing space510A is deposited on the filter member532, it is re-vaporized thereon. The gas material flows through the fine holes532binto the internal space530A, and is then delivered through the gas material delivery passage531a. The fine holes532bformed in the filter member532are designed in accordance with the same dimensions as those of the second embodiment.

In this embodiment, a filter member534is preferably disposed within the internal space530A (between the filter member532and gas material delivery passage531a), as shown by broken lines. The filter member534may be the same as the filter member of the first embodiment or fifteenth embodiment. Preferably, at positions other than the peripheral portion, the filter member534is fixed to and in thermal contact with heat transfer portions, which protrude from the sidewall531, as in the first embodiment. In this case, this heat transfer portions are configured to transfer heat from the filter member532to the filter member534. Heating means may be embedded in the sidewall531, while the heat transfer portions are attached to the sidewall531and are in thermal contact with the filter member534.

FIGS. 20A and 20Bare a schematic front view and a schematic side view, respectively, showing a modification of spray means. This spray means620includes a plurality of (three in the example shown in the figure) source material supply pipes621, a spray gas supply pipe622, and a spray nozzle623. Source materials supplied through the source material supply pipes621are independently prepared by mixing in the spray nozzle623, and sprayed from respective spray ports623aalong with corresponding parts of the spray gas. For example, this structure is applied to a case where three gas materials (derivatives of Pb, Zr, and Ti (organic metal compounds)) are supplied to form PZT (lead zirconate-titanate). In this case, the three source materials are supplied into the spray means620, and independently prepared by mixing within the spray nozzle623. Then, three source materials are sprayed from respective spray ports623aalong with corresponding parts of the spray gas.

The spray means620can provide the same effect as the spray means520of the nineteenth embodiment. Further, the spray ports623aare disposed exclusively for respective source materials, so the source materials can be advantageously adjusted in spray conditions (such as the source material spray amount, mixture spray gas amount, and spray pressure).

FIGS. 20C and 20Dare a schematic front view and a schematic side view, respectively, showing another modification of spray means. This spray means720includes a plurality of source material supply pipes721, a spray gas supply pipe722, and a spray nozzle723. The spray nozzle23is provided with gas material introduction blocks723B to723D, which correspond to and communicate with a plurality of source material supply pipes721. Source materials supplied through the source material supply pipes721respectively flow from the gas material introduction blocks723D,723C, and723B into a passage connected to a spray port723a, and are mixed with each other within the spray nozzle723. Then, the source materials are sprayed from the spray port723aalong with a spray gas coaxially supplied through a spray gas distribution cell723A.

The spray means720can uniformly mix source materials of different types. The mixed source materials are vaporized in a vaporizing space and supplied into a film formation chamber. In this case, reproducibility of the film composition ratio is improved.

FIG. 21is a schematic structural view showing a reaction processing apparatus (semiconductor processing apparatus) according to an embodiment of the present invention. For example, this reaction processing apparatus is a CVD apparatus for forming a thin film, using a gas material. This reaction processing apparatus includes a source material supply section200, a vaporizer100(500) configured to vaporize a source material supplied from the source material supply section200, and a reaction processing section300configured to perform a process using a gas material generated by the vaporizer.

FIG. 22is a schematic structural view showing the inner structure of the source material supply section200. The source material supply section200has source material containers202A to202C storing source materials A to C, from which the source materials A to C are supplied at controlled flow rates to the vaporizer100(500) through liquid feed lines204A to204C. For example, the source material containers202A to202C store materials for semiconductor devices, such as Pb, Zr, and Ti (PZT), or Pb, Zr, Ti, and Nb (PZTN), in a case where a ferroelectric thin film is formed; organic metal compounds of Ba, Sr, and Ti in a case where a high dielectric thin film is formed; or Bi, Sr, and Cu in a case where a superconducting thin film is formed. The number of source materials and source material containers is not limited to that of the example shown in the figure, and it may be arbitrarily selected as needed. A solvent container202D is disposed to store a solvent which is to be supplied through a liquid feed line204D. Further, a drain container202E is connected through drain lines203to the liquid feed lines204A to204D extending from the source material container202A to202C and solvent container202D.

One side ends of the liquid feed lines204A to204D are respectively inserted into the liquids within the source material containers202A to202C and solvent container202D. The liquid feed lines204A to204D are respectively provided with flow rate adjusting means (for example, a flow rate controller, such as a mass flow meter)205A to205D on downstream sides therefrom. The liquid feed lines204A to204D further extend downstream from the flow rate adjusting means to supply the source materials to the vaporizer100(500). The flow rate adjusting means205A to205D are configured to receive control signals from a controller (not shown) and thereby adjust the flow rates.

The source material supply section200further has a gas feed line206for feeding an inactive gas or the like, and gas supply lines206A to206D branched therefrom. The gas supplied through the gas supply lines206A to206D applies pressure to deliver the source materials A to C and solvent to the respective liquid feed lines204A to204D. The liquid feed line204D for supplying the solvent is connected through a solvent feed line207to the liquid feed lines202A to202C for supplying the source materials, and the gas supply line206A to206C. Further, an exhaust apparatus (not shown) is connected through a vacuum line208to the drain container202E.

The gas supply lines206A to206D are respectively provided with check valves CH, and all lines are respectively provided with switch valves DV (diaphragm valves) at suitable positions, as shown inFIG. 22. Further, the source material feed lines are preferably provided with separators (de-aerators: not shown) upstream the flow rate adjusting means205A to205D.

Referring toFIG. 21again, according to the vaporizer100(500), a source material vaporized within a vaporizing chamber110(510) is delivered through a delivery part130(or150,150′,150″,160,160′,150X,150Y,150Z,170,170′,180,190,230,330,430, or530) to a source material feed line140.

The source material feed line140includes a source material supply passage141, and exhaust passages143and144connected to an exhaust system (for example, a vacuum pump). The source material supply passage141is provided with a gas material re-vaporize filter142including the filter member described above (133,153,153′,163,153X,153Z,173,183,193,232,334,433, or532). The re-vaporize filter142has the same structure as the delivery part described above (130,150,150′,150″,160,160′,150X,150Y,150Z,170,170′,180,190,230,330,430, or530). Specifically, the re-vaporize filter142is formed independently of a vaporizer, although it has the same structure as the delivery part, while each of the gas material supply sections described previously is formed as a part of a vaporizer. The gas material supply structure may be provided with only one of the delivery part and re-vaporize filter142.

The processing section300includes a reaction chamber301, in which a susceptor304is disposed to place a target substrate, such as a semiconductor wafer, thereon. A gas feed portion (showerhead)303is disposed within the reaction chamber301to face the susceptor304. The gas material supplied from the vaporizer100(500) is delivered (along with a suitable carrier gas) through the showerhead303into the reaction chamber301. Further, a reaction gas (for example, an oxidizing gas, such as oxygen gas) supplied from another gas feed line305is delivered through the showerhead303into the reaction chamber301. An exhaust line306is connected to the reaction chamber301to exhaust the interior of the reaction chamber301.

According to this reaction processing apparatus, the amount of mist and particles entering the reaction chamber301can be remarkably reduced by the delivery part of the vaporizer (130,150,150′,150″,160,160′,150X,150Y,150Z,170,170′,180,190,230,330,430, or530) or the re-vaporize filter142. Consequently, the quality of a process performed within the reaction chamber301(for example, a film formation process) is improved. In the delivery part and re-vaporize filter, a filter member disposed therein is uniformly heated, so it increases the vaporization efficiency and is prevented from being clogged. It follows that the maintenance of the feed line is less frequency, while the conductance of the feed line is maintained.

FIG. 23is a schematic structural view showing a reaction processing apparatus (semiconductor processing apparatus) according to another embodiment of the present invention. This structure is the same as the structure described above, in that a source material is supplied from a source material supply section200to a vaporizer100(500), and a gas material is supplied from the vaporizer100(500) through a source material supply passage141to a processing section300. On the other hand, this structure differs from the structure described above, in that a purge line145for supplying an inactive gas, such as Ar gas, is connected to the source material supply passage141. Further, this structure does not include the re-vaporize filter142and exhaust passage143.

According to this structure, the distance between the vaporizer100(500) and reaction chamber301(the length of the source material supply passage141) is set to be as short as possible, so that the amount of vaporized gas within the source material supply passage is small. With this arrangement, generation of particles is suppressed in the source material supply system, and thus the quality of a film formed within the reaction chamber301is improved.

FIG. 24is a graph showing change with time in the pressure inside a vaporizing chamber (dependency of the inner pressure on the source material supply period), comparing the vaporizer according to the second embodiment with a conventional vaporizer (including a filter member disposed in a conventional manner).

As indicated with a line L2, the conventional vaporizer went beyond the upper limit pressure before the source material supply period reached 100 hours. In this case, the vaporizer was then subjected to a purge treatment of supplying an inactive gas, such as N2, while heating the vaporizer, to temporally decrease the inner pressure. However, the vaporizer went beyond the upper limit pressure again in a short time thereafter (FIG. 24does not show the purge treatment period). This was thought to be caused due to a large amount of solid substances being deposited on the filter member, which decreased the conductance.

On the other hand, as indicated with a line L1, the vaporizer according to the second embodiment showed a pressure far lower than the upper limit pressure even after the source material supply period reached 600 hours. Accordingly, it has been found that the vaporizer according to the second embodiment can remarkably suppress decrease in the conductance, as compared to the conventional structure. In the case of the second embodiment, decrease in the conductance was hardly observed, but this does not mean malfunction of the filter member. Rather than this, it was experimentally confirmed that the second embodiment reduced the amount of particles entering the reaction chamber to a half or less of that observed in the conventionally structure.

Particularly, in the case of the conventionally structure, the amount of particles entering the reaction chamber was mainly reduced by an inline filter disposed downstream. In contrast, in the case of the second embodiment, the amount of particles entering the reaction chamber scarcely changed, when an inline filter disposed downstream was detached. This was thought to be caused because the vaporizer according to the second embodiment reduced the amount of particles to such a low level that was scarcely influenced by whether the inline filter was present or not.

As shown inFIG. 24, in the case of the second embodiment, the inline filter disposed downstream was detached when the source material supply period reached about 170 hours (corresponding to the broken line inFIG. 24), and measurement of the inner pressure change was continued. As a result, the inner pressure was slightly decreased after 170 hours as shown in the graph. Accordingly, it was demonstrated that the second embodiment remarkably suppressed decrease in the conductance due to clogging of the filter member, and greatly reduced the amount of particles flowing downstream.

According to the present invention, the supply structure, vaporizer, and reaction processing apparatus associated with a gas material are not limited to the examples shown in the figures, and they may be modified in various manners without departing from the spirit and scope of the present invention. For example, the respective features of the sidewall, internal space, heating means, filter member, shield plate, heat transfer portions (heat transfer columns), and communication clearance in one embodiment are not limited to their combination shown in that embodiment, and they may be applied to another embodiment, independently of each other.

INDUSTRIAL APPLICABILITY

According to the present invention, there is provided a vaporizer that can decrease mist and particles in a gas material.