APPARATUS AND METHOD FOR FORMING THIN FILM

Provided are an apparatus and method for forming a thin film. The apparatus for forming a thin film include a chamber configured to define a substrate processing space therein, a substrate support part connected to the chamber to support a substrate inside the chamber, a heat source part connected to the chamber to face the substrate support part, and a plasma generation part connected to the chamber to supply radicals between the substrate support part and the heat source part at at least two points.

TECHNICAL FIELD

The present disclosure relates to an apparatus and method for forming a thin film, and more particularly, to an apparatus and method for forming a thin film, which are capable of improving uniformity of the thin film.

BACKGROUND ART

Recently, a rapid thermal processing (RTP) method is widely used as a method of thermally processing a substrate or the like.

The rapid thermal processing method is a method for irradiating radiation emitted from a heat source such as a tungsten lamp onto a substrate to thermally process the substrate. When compared to existing method for thermally processing a substrate using a furnace, such a rapid thermal processing method has an advantage of improving thermal processing quality of a substrate because the substrate is quickly heated and cooled, and pressure conditions or temperature bands are easily controlled.

An apparatus for forming a thin film using the rapid thermal processing method includes a chamber providing a space in which the substrate is mainly processed, a substrate support disposed inside the chamber to support the substrate, and a plasma generator that activates the heat source irradiating the radiation onto the substrate support and a process gas to supply the heat source and the process gas into the chamber. Here, the heat source and the substrate support are installed on upper and lower portions of the chamber, respectively, and, in the chamber, a (vertical) distance between the substrate and the heat source is short to efficiently heat the substrate, and a long and wide processing space is formed in a horizontal direction. Thus, since it is difficult to install the plasma generator inside the chamber, radicals are generated using the plasma generator outside the chamber during the forming of the thin film, and then the radicals are supplied through a sidewall of the chamber.

However, since the processing space inside the chamber is formed to be long and wide in the horizontal direction, there is a limitation in that the radicals are not sufficiently diffused throughout the processing space to deteriorate uniformity of the thin film.

In order to solve this limitation, a method for locally adjusting a temperature of the substrate using the heat source is used. However, in this case, there is a limitation in that the substrate is deformed by thermal stress due to a temperature deviation, and productivity is deteriorated.

DISCLOSURE

Technical Problem

The present invention provides an apparatus and method for forming a thin film, which are capable of improving uniformity of the thin film.

Technical Solution

An apparatus for forming a film according to an embodiment of the present invention includes: a chamber configured to define a substrate processing space therein; a substrate support part connected to the chamber to support a substrate inside the chamber; a heat source part connected to the chamber to face the substrate support part; and a plasma generation part connected to the chamber to supply radicals between the substrate support part and the heat source part at at least two points.

The chamber may be provided in a hollow shape having a width, a thickness, and a height, and the processing space is defined to have a height less than each of a width and a thickness thereof, and the apparatus may include at least two injection ports passing through the chamber in a width or thickness direction of the chamber and an exhaust port passing through the chamber to face the at least two injection port.

The at least two injection ports may be disposed at the same height in the height direction of the chamber.

The at least two injection ports may be disposed parallel to each other, or at least one of the at least two injection ports is disposed to be inclined in a horizontal direction.

The substrate support part may include a substrate support that is rotatable and installed inside the chamber, and a spaced distance of the injection portions may be less than a radius of the substrate support.

The apparatus may further include a guide member disposed inside the chamber to define a passage communicating with each of the at least two injection ports.

The exhaust port may include: first exhaust ports having a spaced distance greater than a diameter of the substrate support part; and a second exhaust port disposed between the first exhaust ports.

The plasma generation part may include: a plurality of plasma generators configured to generate radicals; and at least two waveguides configured to connect the plurality of plasma generators to the at least two injection ports, respectively.

The plasma generation part may include: a plasma generator configured to generate radicals; anda waveguide configured to connect the plasma generator to the at least two injection ports, wherein the waveguide may include at least two branch tubes configured to connect the plasma generator to the at least two injection ports.

The plasma generation part may include a flow regulation member installed in the waveguide.

The plasma generation part may include a heating member installed on the waveguide.

A method for forming a thin film according to an embodiment of the present invention includes: loading a substrate into a chamber; heating the substrate; generating radicals; supplying the radicals to one side of the substrate in a direction parallel to the substrate through at least two paths; allowing the radicals to be in contact with the substrate so as to form a thin film; and exhausting residual radicals to the other side of the substrate.

The supplying of the radicals may include supplying the radicals at the same height in a direction in which the substrate extends.

The supplying of the radicals may include supplying the radicals through a first path comprising a central portion of the substrate from one side to the other side of the chamber and a second path comprising an edge of the substrate.

The supplying of the radicals may include: generating the radicals outside the chamber; and transferring the radicals to the chamber, wherein the transferring of the radicals may include adjusting a temperature of the radicals.

The supplying of the radicals may include regulating a flow rate of the radicals supplied to each of at least two paths.

The exhausting of the residual radicals may include adjusting at least one of a position, at which the residual radicals are exhausted, or an amount of radicals to be exhausted.

Advantageous Effects

According to the apparatus and method for forming the thin film according to the embodiments of the present invention, the uniformity of the thin film may be improved. That is, the radicals for forming the thin film may be in uniform contact with the substrate to uniformly form the thin film on the entire substrate. In addition, in the process of forming the thin film, the deformation of the substrate due to the thermal stress may be minimized. Therefore, the process yield may be improved, and the productivity may be improved.

DETAILED DESCRIPTION

FIG.1is a perspective view illustrating an apparatus for forming a thin film according to an embodiment of the present invention,FIG.2is a cross-sectional view illustrating the apparatus for forming the thin film, which is taken along line A-A′ inFIG.1, andFIG.3is a cross-sectional view illustrating the apparatus for forming the thin film, which is taken along line B-B′ inFIG.1.

Referring toFIGS.1to3, an apparatus for forming a thin film according to an embodiment of the present invention may include a chamber100having a space in which a substrate W is processed therein, a substrate support part300connected to the chamber100to support the substrate W inside the chamber100, a heat source part200connected to the chamber100to face the substrate support part300, and a plasma generation part400that supplies radicals between the substrate support part300and the heat source part200at at least two points. Here, the heat source part200may be installed on an upper portion of the chamber100, and the substrate support part300may be installed on a lower portion of the chamber100. Here, the apparatus for forming the thin film may include a rapid thermal processing (RTP) device that irradiates radiation emitted from a heat source onto the substrate to heat the substrate.

Hereinafter, a direction in which radicals are moves, i.e., a direction in which the radicals are injected into the chamber and then discharged is referred to as a thickness direction, and a direction horizontally crossing the thickness direction is referred to a width direction with respect to the chamber100. Also, a vertical direction of the chamber100is referred to as a height direction.

The chamber100may include a chamber body110having a substantially rectangular frame shape with opened upper and lower portions and a transmission window120connected to the upper portion of the chamber body110.

The chamber body110may be integrally manufactured as a single body, but may also have an assembly body in which several components are connected to be coupled to each other. In this case, a sealing part (not shown) may be additionally provided on the connection portion between the components. Thus, when heating or cooling the substrate W, energy input into the apparatus may be reduced. A gate130through which the substrate W is loaded or unloaded may be provided in the chamber body110. In addition, the chamber body110may include an injection port140(142and144) through which the radicals for forming the thin film are injected and an exhaust port150through which a gas inside the chamber100is discharged, and residual radicals remaining after forming the thin film are exhausted. Here, the gate130, the injection port140, and the exhaust port150may be provided in the width direction of the chamber body110, and the injection port140and the exhaust port150may be provided to face each other.

The transmission window120may be connected to the upper portion of the chamber body110to seal the inside of the chamber body110. The transmission window120may transmit the radiation emitted from the heat source of the heat source part200installed on the upper portion the chamber100and may be made of a transparent material such as quartz or sapphire that is capable of withstanding a high temperature.

The chamber100may be provided in a hollow shape having a width, thickness, and a height so as to define the processing space capable of processing the substrate W therein. Here, the chamber100is provided to have a height less than each of the width and thickness and may define the processing space that is longer and wider in the horizontal direction than in the vertical direction.

At least two injection ports140may be provided in the chamber body110. Two or more injection ports140may be provided. However, an example in which two injection ports140are provided in the chamber body110will be described here. The two injection ports140may be provided to be spaced apart from each other at the same height in the height direction of the chamber body110. Here, the two injection ports140may be provided to be disposed at a position higher than that of at least the substrate support320. The two injection ports140may be provided to have a spaced distance less than a radius of the substrate W or the substrate support320. For example, one injection port142of the two injection ports140may be provided to supply the radicals toward a center of the substrate W or the substrate support320, and the other injection port144may be provided to supply the radicals toward an edge of the substrate W or the substrate support320. If the spaced distance between the injection ports140is too long, it is difficult to uniformly supply the radicals into the chamber100, and thus, the uniformity of the thin film disposed on the substrate W may be deteriorated. On the other hand, if the spaced distance between the injection ports140is short, the radicals may be more uniformly supplied onto the chamber100to improve the uniformity of the thin film disposed on the substrate W. However, here, there is difficulty in connecting a waveguide420of the plasma generation part400.

The two injection ports140may be disposed parallel to each other. Alternatively, at least one of the two injection ports140may be inclined in the horizontal direction. For example, one of the two injection ports140may be disposed toward the center of the substrate support320, and the other may be disposed to be inclined toward the outside of the substrate support320from the edge of the substrate support320. Thus, since the radicals are diffused in the wider area inside the chamber100, the substrate W may be in sufficient contact with the radicals to further improve the uniformity.

FIG.4is a view illustrating a state in which a guide member is installed in the chamber.

Referring toFIG.4, a guide member170for guiding the movement direction of the radicals may be disposed inside the chamber100. The guide member170may be disposed between the substrate support320and the injection port140to extend along a direction in which the injection port140extends. The guide member170may guide the radicals to move in a target direction by providing a passage communicating with the injection port140. Through this, the uniformity of the thin film disposed on the substrate W may be more precisely controlled. The guide member170may be provided in the form of a partition wall extending vertically on both sides of the injection port140or may be provided in the form of a pipe inserted into the injection port140. Here, when the guide member170is provided in the form of the partition wall, the guide member170may be provided to completely block a gap between the injection ports140(142and144) or may be provided to partially block a portion between the injection ports140(142and144). That is, the passage provided by the guide member170may be provided in a tubular shape or may be provided in a concave groove shape. Hereinafter, an example in which the passage is provided in the tubular shape having an inner diameter will be described.

The guide member170may provide a passage having the same inner diameter as an inner diameter of the injection port140or may provide a passage having an inner diameter that gradually increases toward the substrate support320. Alternatively, the guide member170may provide a passage having a diameter greater than a diameter of the injection port140or may provide a passage having a diameter less than a diameter of the injection port140. Alternatively, the passages provided by the guide member170may be provided to have different diameters. For example, the passage communicating with the injection port142through which the radicals are supplied toward the center of the substrate support320may be provided to have a diameter greater than that of the passage communicating with the injection port144through which the radicals are supplied toward the edge of the substrate support320. Alternatively, the passage communicating with the injection port142through which the radicals are supplied toward the center of the substrate support320may be provided to have a diameter less than that of the passage communicating with the injection port144through which the radicals are supplied toward the edge of the substrate support320.

Here, the two injection ports142and144are provided in the chamber body110, and the guide member17is provided inside the chamber body110to guide the movement direction of the radicals. However, a slit-shaped injection port may be provided in the chamber body, and two waveguides may be connected to the injection port. In addition, the guide member may be provided inside the chamber body to guide the movement direction of the radicals injected into each of the waveguides. In this case, the guide member may be provided in a shape of which a width increases toward the substrate support320so that the radicals are sufficiently diffused over the entire substrate W.

The exhaust port150may be provided to pass through the chamber body110at a side facing the injection port140. Here, the exhaust port150may be provided to face the injection port140so that the radicals uniformly flow while being in contact with a surface of the substrate W inside the chamber100. The exhaust port150may be connected to an exhaust line (not shown), in which a pump (not shown) is installed, to discharge the gas and radicals inside the chamber100and also perform pressure control such as forming of a vacuum state inside the chamber100. The exhaust port150may include at least one of a pair of first exhaust ports152aand152bprovided to have a spaced distance greater than the diameter of the substrate support320or one second exhaust port154provided between the first exhaust ports152aand152b. For example, only the first exhaust ports152aand152bor only the second exhaust port154may be provided in the chamber100. Alternatively, both the first exhaust ports152aand152band the second exhaust port154may be provided in the chamber100. In this case, since the radicals injected into the chamber100are more uniformly diffused throughout the inside of the chamber100so as to be in uniform contact over the entire substrate W, the uniformity of the thin film disposed on the substrate W may be further improved.

The first exhaust ports152aand152band the second exhaust port154may be connected to exhaust lines different from each other, respectively. In this case, an exhaust amount adjusting member (not shown) capable of adjusting an exhaust amount is installed in each of the exhaust lines to adjust an amount of radicals or gases discharged through each of the first exhaust ports152aand152band the second exhaust port154.

The heat source part200is installed on the upper portion of the chamber100to heat the substrate W loaded into the chamber100. The heat source part200may include a hollow support body210with an opened lower portion and a heat source220installed inside the support body210.

The support body210may be provided to have an area similar to that of the chamber100or a process space inside the chamber100, and a lower portion of the support body210may be opened to allow radiation emitted from the heat source220to proceed toward the chamber100. Here, an uneven structure (not shown) such as a recessed groove may be provided on the support body210, or a reflective film (not shown) may be disposed on the support body210to reflect the radiation emitted from the heat source220toward the chamber100. The support body210may include a passage (not shown) through which a cooling medium or the like is circulated to prevent overheating due to the radiation emitted from the heat source220.

The heat source220may include a lamp capable of emitting radiation, such as a tungsten halogen lamp, a carbon lamp, and a ruby lamp and may be provided in various shapes such as a linear shape or a bulb shape.

The substrate support part300may be installed on the lower portion of the chamber100to face the heat source part200. The substrate support part300may include a substrate support320capable of supporting the substrate W thereon, and a driver330for rotating the substrate support320. In addition, the substrate support part300may further include a lift member340for vertically moving the substrate W, a temperature measuring device (not shown) for measuring the temperature of the substrate W, and the like. The substrate support part300may include a separate housing310and be coupled to the lower portion of the chamber100to seal the inside of the chamber100.

The substrate support320may include an electrostatic chuck to adsorb and maintain the substrate110by using electrostatic force so that the substrate W is seated and supported. Alternatively, the substrate support200may support the substrate W through vacuum adsorption or mechanical force. The substrate support320may be provided in a shape corresponding to the shape of the substrate W, for example, a circular shape and may be manufactured to be larger than the substrate W.

The driver330may be connected to a lower portion of the substrate support320through a rotation shaft332and may rotate the substrate W when forming the thin film on the substrate W.

The plasma generation part400includes a process gas supplier430, a plasma generator410that receives power from the outside to generate plasma and activates a process gas supplied from the process gas supplier430to generate radicals, and a waveguide420connecting the plasma generator410to the chamber to supply the radicals into the chamber100. Here, the plasma generation part400may include two plasma generators410and two waveguides420to supply the radicals to each of the two injection ports140. In addition, the plasma generation part400may include a flow regulator (not shown) provided in at least one of the two waveguides420so as to regulate a flow rate of the radicals supplied to each injection port140.

The plasma generation part400may include a heating member (not shown) for adjusting a temperature of the waveguide420so as to maintain a constant temperature of the radicals supplied from the plasma generator410to the chamber100. That is, the radicals generated by the plasma generator410may move along the waveguide420and be supplied into the chamber100. In this case, when the temperature of the radicals in the waveguide420is lowered, there is a limitation in that the radicals are converted into a gaseous state due to bonding between the radicals. Therefore, the heating member (not shown) may be installed in the waveguide420to constantly maintain the temperature of the radicals.

Here, although it is described that the two plasma generators410and the two waveguides420are provided, when the number of injection ports140is two or more, for example, three, three plasma generators410and three waveguides420may also be provided.

The process gas supplier430may supply a gas for forming the thin film to the plasma generator410and may supply various process gases such as O2, N2, H2, N2O, NH3, etc. according to the type of the thin film to be manufactured. Here, an example in which O2is supplied to the plasma generator410by the process gas supplier430to form an oxide film on the substrate W will be described. The process gas supplier430may supply the process gas to the two plasma generators410. In this case, the process gas supplier430may supply the two plasma generators410at the same rate or different flow rates of the process gas. Through this, an amount of radicals generated in the two plasma generators410may be adjusted to regulate the flow rate of the radicals supplied through the two injection ports140.

FIG.5is a cross-sectional view illustrating an apparatus for forming a thin film according to another embodiment of the present invention.

Referring toFIG.5, an apparatus for forming a thin film according to another embodiment of the present invention are almost similar to the apparatus for forming the thin film according to the foregoing embodiment except for a plasma generation part400.

The plasma generation part400may include a plasma generator410for generating radicals and a waveguide420for connecting the plasma generator410to at least two injection ports140, and the waveguide420may include at least two branch tubes420band420cto connect the plasma generator410to the at least two injection ports.

That is, the plasma generation part400may generate radicals in one plasma generator410and supply the radicals to at least two injection ports140through one waveguide420. Thus, the waveguide420may include at least two branch tubes420band420cto supply the radicals to the at least two injection ports140. The branch tubes420band420cmay be provided in the same number as the injection ports140. Here, an example in which the two branch tubes420band420care provided in the waveguide420to supply the radicals to the two injection ports140will be described.

The waveguide420may include a connection tube420aconnected to the plasma generator410and two branch tubes420band420cconnected to the connection tube420aand respectively connected to the two injection ports140. The waveguide420may be provided to have an approximate ‘U’ shape or ‘V’ shape.

In addition, a flow regulation member425for regulating a flow rate of the radicals may be provided in at least one of the two branch tubes420band420c. The flow regulation member425may include a pendulum valve or the like and may be installed only in one of the two branch tubes420band420cas illustrated inFIG.5or may be installed in all of the two branch tubes420band420c. Through this, the amount of radicals may be equally adjusted or differently adjusted through the two injection ports140.

Hereinafter, a method for forming a thin film according to an embodiment of the present invention will be described.

A method for forming a thin film according to an embodiment of the present invention may include a process of loading a substrate W into a chamber100, a process of heating the substrate W, a process of generating radicals, a process of supplying the radicals to one side of the substrate W through at least two paths, a process of forming a thin film on the substrate W using the radicals, and a process of exhausting residual radicals to the other surface of the substrate W. Here, the process of forming the thin film is described as being performed time-sequentially, but the order may be variously changed. That is, each process may be performed in a different order or at the same time.

The substrate W prepared for forming the thin film may be loaded into the chamber100through a gate130and then may be seated on an upper portion of a substrate support320. Here, the substrate W may be a silicon substrate, and the inside of the chamber100may be heated to a certain temperature by a heat source part200.

When the substrate W is seated on the substrate support320, the gate130may be closed to form a vacuum state inside the chamber100. In addition, the substrate support320may rotate, and the substrate W may be heated to a process temperature, for example, a temperature for forming an oxide film, through the heat source part200.

In addition, oxygen radicals may be generated in a plasma supply part400, and the generated oxygen radicals may be supplied into the chamber100through an injection port140. Here, the oxygen radicals may be injected and discharged at the same time. Then, the oxygen radicals injected through the injection port140may be discharged through the substrate W to an exhaust port150. The oxygen radicals may be generated in the plasma generator410and then supplied to the chamber100through the waveguide420. Here, the waveguide420may be heated to prevent the temperature of the oxygen radicals from decreasing in the waveguide420.

The oxygen radicals may be supplied into the chamber100through at least two injection ports140. The oxygen radicals supplied into the chamber100may react with the substrate W while moving from one side to the other side of the substrate W to form a thin film, for example, an oxide film. Here, the oxygen radicals may be supplied through at least two paths parallel to the substrate W so that the oxygen radicals are in sufficient contact with a surface of the substrate W. The at least two paths may refer to positions, at which at least two injection ports140are formed, and may include a first path formed at the same height in a direction in which the substrate W extends and including a central portion of the substrate W and a second path including an edge of the substrate W.

The oxygen radicals injected into the chamber100through the first path and the second path may be sufficiently diffused throughout a processing space inside the chamber100that is formed to be long and wide in horizontal direction. Particularly, since the oxygen radicals are sufficiently diffused from the central portion to one edge of at least the substrate W, a contact area with the substrate W may further increase. Since the substrate W rotates while forming the thin film, the oxygen radicals may be in sufficient contact with the substrate W, so that the thin film, for example, the oxide film is uniformly formed over the entire substrate W.

In the process of supplying the oxygen radicals into the chamber100, the oxygen radicals may be supplied at the same flow rate into at least two injection ports140, or the oxygen radicals having different flow rates may be supplied into at least two injection ports140. For example, more oxygen radicals may be supplied toward the edge of the substrate support320rather than toward the central portion of the substrate support320, and more oxygen radicals may be supplied toward the central portion of the substrate support320rather than toward the edge of the substrate support320.

When the oxide film is formed on the substrate W, the supply of the oxygen radicals may be stopped, and the rotation of the substrate support320may be stopped, and then, the substrate W may be unloaded from the chamber100.

Thereafter, uniformity of the oxide film formed on the substrate W is measured, process conditions may be adjusted in a subsequent process according to the measurement result, and then the thin film may be manufactured. For example, the flow rate of the oxygen radicals supplied through at least two paths may be regulated according to a thickness of the thin film formed on the substrate W, or a position or amount of residual oxygen radicals to be exhausted may be adjusted. Through this, since the thickness of the thin film formed on the substrate W is locally adjusted, the uniformity of the thin film manufactured in the subsequent process may be improved.

Although the present invention has been described with reference to the accompanying drawings and foregoing embodiments, the present invention is not limited thereto and also is limited to the appended claims. Thus, it is obvious to those skilled in the art that the various changes and modifications can be made in the technical spirit of the present invention.

INDUSTRIAL APPLICABILITY

According to the present invention, the thin film may be uniformly formed over the entire substrate by allowing the radicals for forming the thin film to be in uniform contact with the substrate, and the substrate may be suppressed from being deformed by thermal stress to improve process yield and productivity.