GAS HEATING APPARATUS, SEMICONDUCTOR MANUFACTURING APPARATUS, HEATING ELEMENT, AND SEMICONDUCTOR MANUFACTURING METHOD

A gas heating apparatus includes a heating element having a flat plate shape, a heat-resistant enclosure in which a space having a flat plate shape is provided, the heating element being disposed in the space with a gap provided between the heating element and the heat-resistant enclosure, a gas inlet joint connected to the heat-resistant enclosure to allow gas to flow into the space, a gas outlet joint connected to the heat-resistant enclosure to allow the gas that has passed through the space to flow out, and an induction coil disposed in parallel with the heating element on a lower surface of the heat-resistant enclosure, the induction coil inductively heating the heating element on the basis of electric power supplied.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to a gas heating apparatus, a semiconductor manufacturing apparatus, a heating element, and a semiconductor manufacturing method.

Description of the Background Art

In a semiconductor manufacturing process, after a pattern of organic material is formed by lithography using a resist, etching is performed on an oxide film and a metal material by dry etching using several types of gas energized through application of a high-frequency output.

Thereafter, in order to remove the resist, a chemical liquid is used to dissolve the resist. In a conventional general semiconductor manufacturing apparatus, a chemical liquid process is performed by discharging a chemical liquid at a predetermined flow rate while rotating a semiconductor wafer at a predetermined rotation speed and causing a chemical liquid nozzle to perform a scan at a predetermined speed so as to cause the chemical liquid to uniformly spread all over a processing surface of the semiconductor wafer. In order to ensure sufficient in-plane uniformity in the chemical liquid process, it is necessary to supply gas heated to a predetermined temperature to the semiconductor wafer.

A gas heating apparatus may be used in a method for heating the gas to the predetermined temperature. For example, in the technique disclosed in Japanese Patent Application Laid-Open No. 2000-48943, a plurality of flat heating elements having different sizes are stacked on top of each other in a cylindrical heating enclosure, and an induced magnetic field is generated by an induction coil wound into a cylindrical shape to heat the plurality of flat heating elements.

In the technique disclosed in Japanese Patent Application Laid-Open No. 2000-48943, the density of magnetic field lines of the induced magnetic field generated by the induction coil thus wound becomes higher and curved more sharply as it is closer to the induction coil, so that it is not easy to set the plurality of heating elements stacked on top of each other to the same temperature. Further, the plurality of flat heating elements are stacked on top of each other in the cylindrical heating enclosure, so that a region through which the gas passes becomes wider at a position away from the heating elements such as a curved surface portion of the heating enclosure. This makes it difficult to efficiently heat or cool the gas.

As described above, in the technique disclosed in Japanese Patent Application Laid-Open No. 2000-48943, it is necessary to further increase the thermal capacity of the heating elements or to further increase the area of the heating elements in order to stably obtain gas having a desired temperature, which deteriorates response when heating or cooling the gas.

SUMMARY

An object of the present disclosure is to provide a technique that allows an improvement in response when heating or cooling gas.

A gas heating apparatus according to the present disclosure includes a heating element having a flat plate shape, a heat-resistant enclosure, a gas inlet joint, a gas outlet joint, and an induction coil. In the heat-resistant enclosure, a space having a flat plate shape is provided, and the heating element is disposed in the space with a gap provided between the heating element and the heat-resistant enclosure. The gas inlet joint is connected to the heat-resistant enclosure to allow gas to flow into the space. The gas outlet joint is connected to the heat-resistant enclosure to allow the gas that has passed through the space to flow out. The induction coil is disposed in parallel with the heating element on a lower surface of the heat-resistant enclosure and inductively heats the heating element on the basis of electric power supplied.

The induction coil is disposed in parallel with the heating element on the lower surface of the heat-resistant enclosure, so that the magnetic flux distribution of the induction coil becomes uniform and thus optimized. This allows the temperature of the heating element during heating or cooling to be uniform.

Furthermore, the heating element having a flat plate shape is disposed, with a gap provided around the heating element, in the space having a flat plate shape as with the heating element, so that the gap around the heating element becomes uniform. This allows the gas passing through the space of the heat-resistant enclosure to be uniformly heated or cooled. As described above, gas having a desired temperature can be stably obtained without increasing the thermal capacity of the heating element or increasing the area of the heating element, so that it is possible to improve the response when heating or cooling the gas.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Preferred Embodiment

A description will be given of a first preferred embodiment with reference to the drawings.FIG.1is a cross-sectional view of a gas heating part50of a gas heating apparatus11a(seeFIG.5) according to the first preferred embodiment.

As shown inFIG.1, the gas heating part50of the gas heating apparatus11a(seeFIG.5) includes a heating element51having a flat plate shape, a guide plate52having a flat plate shape, a straightening plate53, a heat-resistant enclosure54, a gas inlet joint55, a gas outlet joint56, an induction coil57, and a power supply58.

The heat-resistant enclosure54includes a heat-resistant enclosure guide plate holder54a, heat-resistant enclosure straightening plate holder54b, and heat-resistant enclosure base54c. The heat-resistant enclosure guide plate holder54ais formed into, for example, an annular shape in a top view. An annular groove54eis formed along an inner edge portion of an upper surface of the heat-resistant enclosure guide plate holder54ato accommodate an outer edge portion of the guide plate52. The heat-resistant enclosure straightening plate holder54bis formed into, for example, an annular shape in a top view and is disposed on the upper surface of the heat-resistant enclosure guide plate holder54a. An inner edge portion of a lower surface of the heat-resistant enclosure straightening plate holder54bis in contact with an outer edge portion of an upper surface of the guide plate52, and the heat-resistant enclosure straightening plate holder54band the heat-resistant enclosure guide plate holder54ahold the guide plate52.

An annular groove54fis formed along an inner edge portion of an upper surface of the heat-resistant enclosure straightening plate holder54bto accommodate an outer edge portion of a straightening plate portion53aserving as a part of the straightening plate53. The heat-resistant enclosure base54cis disposed on the upper surface of the heat-resistant enclosure straightening plate holder54b. An opening54gis formed through inner peripheral sides of the heat-resistant enclosure straightening plate holder54band the heat-resistant enclosure guide plate holder54a. A recessed portion54hrecessed upward is formed at a position facing the opening54gon a lower surface of the heat-resistant enclosure base54c. A peripheral edge portion of the recessed portion54hon the lower surface of the heat-resistant enclosure base54cis in contact with an outer edge portion of an upper surface of the straightening plate portion53a, and the heat-resistant enclosure base54cand the heat-resistant enclosure straightening plate holder54bhold the straightening plate portion53a. A bulging portion54dbulging upward is formed at a center portion of an upper surface of the heat-resistant enclosure base54c.

A space54iformed into a flat plate shape is provided between the straightening plate portion53aand the guide plate52in the heat-resistant enclosure54, and the heating element51is disposed in the space54iwith a gap provided around the heating element51.

The straightening plate53includes the straightening plate portion53aand a straightening plate conduit portion53b. The straightening plate conduit portion53bis provided to stand at a center portion of the straightening plate portion53aand extends upward beyond an upper end of the bulging portion54d. The gas outlet joint56is connected to an inside of the straightening plate conduit portion53b.

The gas inlet joint55is connected to an inside of the bulging portion54dwith a conduit portion55ainterposed between the gas inlet joint55and the bulging portion54d. Gas introduced from the gas inlet joint55passes through the conduit portion55a, a gap between the bulging portion54dand the straightening plate conduit portion53b, a gap between the recessed portion54hand the straightening plate portion53a, gas dispersion holes53c(seeFIG.4) of the straightening plate portion53a, a gap around the heating element51in the space54i, a gas outlet port51a1(seeFIG.2), and the straightening plate conduit portion53band flows out from the gas outlet joint56. Herein, as shown inFIG.1, the gas flow is denoted as gas flow60a,60b,60c,60d,60e,60f. Note that the gap around the heating element51in the space54irefers to a gap between the heating element51and the guide plate52and a gap between the heating element51and the straightening plate53.

The induction coil57is disposed in parallel with the heating element51on a lower surface of the heat-resistant enclosure54. Specifically, the induction coil57is disposed in parallel with the heating element51under a lower surface of the guide plate52held by the heat-resistant enclosure guide plate holder54a. When appropriate electric power is supplied from the power supply58to the induction coil57, the heating element51is inductively heated by an appropriate induced current generated in the heating element51. The heating element51inductively heated heats the gas indicated by the gas flow60e.

The guide plate52is made of a non-metal material such as quartz glass so as not to block the induced magnetic field. The straightening plate portion53aof the straightening plate53is made of a metal material such as aluminum having high thermal conductivity so as to efficiently transfer heat radiated from the heating element51to the gas indicated by the gas flow60c,60d,60e. The straightening plate conduit portion53bof the straightening plate53is also made of a metal material so as to be heated by conducted heat. The heat-resistant enclosure guide plate holder54a, the heat-resistant enclosure straightening plate holder54b, and the heat-resistant enclosure base54cthat constitute the heat-resistant enclosure54are each made of a metal material so as to ensure pressure tightness.

The gap between the heating element51and the guide plate52and the gap between the heating element51and the straightening plate53are set as small as possible within a range where the gas flow rate can be secured to allow the gas to be uniformly heated, so that it is possible to improve the response when heating or cooling the gas.

Next, a description will be given of the details of the heating element51.FIG.2is a schematic top view of an example of the heating element51.FIG.3is a schematic top view of another example of the heating element51.FIGS.2and3shows examples obtained as a result of redesigning the shape of the heating element51so as to efficiently agitate the gas nearby the heating element51having a flat plate shape.

As shown inFIG.2, the heating element51is a porous heating element, and includes a disk portion51a, a gas outlet port51a1, and a large number of through holes51a2. The disk portion51ahas an upper surface serving as a first main surface and a lower surface serving as a second main surface opposed to the upper surface. The gas outlet port51a1passing through from the upper surface to the lower surface is provided at a center portion of the disk portion51a, and the large number of through holes51a2passing through from the upper surface to the lower surface are provided in the disk portion51aexcluding a peripheral edge portion and the center portion.

As shown inFIG.3, the heating element51is an uneven heating element and includes a disk portion51b, a gas outlet port51b1, and a large number of irregularities. The disk portion51bhas an upper surface serving as the first main surface and a lower surface serving as the second main surface opposed to the upper surface. The gas outlet port51b1passing through from the upper surface to the lower surface is provided at a center portion of the disk portion51b, and the large number of irregularities are provided over the upper surface and the lower surface of the disk portion51bexcluding a peripheral edge portion and the center portion. Specifically, irregularities on the upper surface of the disk portion51bare composed of the upper surface of the disk portion51band protrusions51b2protruding upward from the upper surface of the disk portion51b, and irregularities on the lower surface of the disk portion51bare composed of the lower surface of the disk portion51band protrusions51b2protruding downward from the lower surface of the disk portion51b.

In the example shown inFIG.2, gas passing along the upper surface of the heating element51having a flat plate shape and gas passing along the lower surface of the heating element51indicated by the gas flow60eshown inFIG.1pass through the through holes51a2to come into contact with each other to generate a turbulent flow, thereby allowing nearby gas to be agitated and allowing the temperature to become further uniform. Further, in the example shown inFIG.3, gas passing along the upper surface of the heating element51having a flat plate shape and gas passing along the lower surface of the heating element51indicated by the gas flow60eshown inFIG.1pass through the large number of irregularities to generate a turbulent flow, thereby allowing nearby gas to be agitated and allowing the temperature to become further uniform.

Next, a description will be given of the details of the straightening plate53.FIG.4is a schematic top view of an example of the straightening plate53.

As shown inFIG.4, the straightening plate53includes the plurality of gas dispersion holes53cin addition to the straightening plate portion53aand the straightening plate conduit portion53b. The plurality of gas dispersion holes53care provided in a peripheral edge portion of the straightening plate portion53aand pass through from the upper surface to the lower surface of the straightening plate portion53a. The gas flow60cpassing along the upper surface of the straightening plate53shown inFIG.1passes through the gas dispersion holes53cto become the gas flow60d, and further passes along the upper surface and the lower surface of the heating element51from the end portion of the heating element51to become the gas flow60eflowing toward the center portion of the heating element51.

Next, a description will be given of a semiconductor manufacturing apparatus according to the first preferred embodiment.FIG.5is a cross-sectional view showing a chemical liquid process in a processing chamber of the semiconductor manufacturing apparatus according to the first preferred embodiment.

As shown inFIG.5, the semiconductor manufacturing apparatus includes a stage rotation mechanism2, a chuck opening and closing mechanism3, a platen4, a cup lift mechanism5, a chemical liquid nozzle6, a chemical liquid nozzle scan mechanism7, a water nozzle8, a chemical liquid temperature control circulation discharge mechanism9, a first gas-liquid separator10a, and a lower surface gas temperature control discharge mechanism11.

The stage rotation mechanism2includes a stage rotation motor2a, a chuck stage2b, and a lower surface gas nozzle2cwhose discharge port is positioned in alignment with a center portion of a semiconductor wafer1. The chuck stage2bholds the semiconductor wafer1using an end portion of the chuck stage2b. The stage rotation motor2arotates the chuck stage2b. The lower surface gas nozzle2csupplies gas to a surface opposed to a processing surface of the semiconductor wafer1.

The chuck opening and closing mechanism3includes a chuck pin base3a, a chuck pin3b, and a support pin3c. The cup lift mechanism5includes a first cup5a, a second cup5b, a cover5c, and a cup base5d.

The chemical liquid nozzle6discharges a chemical liquid14ato the processing surface of the semiconductor wafer1. The chemical liquid nozzle scan mechanism7includes a scan motor7a, a scan shaft7b, and a scan arm7c, and causes the chemical liquid nozzle6to perform a scan on the processing surface of the semiconductor wafer1. The chemical liquid temperature control circulation discharge mechanism9includes a chemical liquid circulation tank9a, a first stock solution tank9b, a second stock solution tank9c, a chemical liquid circulation pump9d, and a chemical liquid temperature controller9e.

The lower surface gas temperature control discharge mechanism11includes the gas heating apparatus11aand an on-off valve11b. The on-off valve11bis disposed adjacent to an inlet of the gas heating apparatus11a. The gas flowing out from the gas heating apparatus11ais supplied to the lower surface gas nozzle2c. The lower surface gas nozzle2cis a nozzle for supplying the gas flowing out from the gas heating apparatus11ato the semiconductor wafer1during the execution of the process on the processing surface of the semiconductor wafer1. Herein, the process that is associated with the lower surface gas nozzle2cand is performed on the processing surface of the semiconductor wafer1includes a chemical liquid process, a water washing process, and a drying process performed in the processing chamber.

Controlling electric power supplied to the induction coil57of the gas heating apparatus11acontrols a temperature of the gas flowing out from the gas heating apparatus11a. Specifically, the gas heating apparatus11ais controlled on the basis of the electric power supplied to the induction coil57to heat or cool the gas to a temperature set for each step of a recipe corresponding to the process performed on the processing surface of the semiconductor wafer1.

With the electric power supplied to the induction coil57, opening the on-off valve11bchanges ambient temperature gas16to temperature-controlled by the gas heating apparatus11ato become temperature-controlled gas17and supplied to the lower surface gas nozzle2c. On the other hand, with no electric power supplied to the induction coil57, opening the on-off valve11bcauses the ambient temperature gas16to pass through the gas heating apparatus11awithout being temperature-controlled by the gas heating apparatus11aand supplied to the lower surface gas nozzle2cas it is.

Note that the processing surface of the semiconductor wafer1is an upper surface of the semiconductor wafer1. The surface opposed to the processing surface of the semiconductor wafer1is an opposite surface opposed to the processing surface of the semiconductor wafer1, and more specifically, a lower surface of the semiconductor wafer1.

FIG.6is a schematic diagram showing a control function of the processing chamber of the semiconductor manufacturing apparatus according to the first preferred embodiment. As shown inFIG.6, an operation PC101includes a man machine interface (MM-IF)101asuch as a touch panel display and a personal computer (PC)101b. A control PLC102includes a programmable logic controller (PLC)102a, a stage rotation module102bthat controls the stage rotation mechanism2, a chuck opening and closing module102cthat controls the chuck opening and closing mechanism3, a cup lift module102dthat controls the cup lift mechanism5, a nozzle scan module102ethat controls the chemical liquid nozzle scan mechanism7, a chemical liquid temperature control circulation discharge module102fthat controls the chemical liquid temperature control circulation discharge mechanism9, a water discharge module102gthat controls a discharge of water15, and a lower surface gas temperature control discharge module102hthat controls the lower surface gas temperature control discharge mechanism11.

An operator sets a carrier (not shown) containing the semiconductor wafer1in a load port (not shown), selects a recipe pre-registered in the PC101bon the MM-IF101a, and inputs a process start. The PC101bpasses a processing parameter specified in the recipe to the PLC102ato start a series of control operations of the PLC102a. The PLC102acontrols a transfer robot (not shown), the processing chamber, and the like, causes the transfer robot to map wafer loading slots in the carrier and to transfer the semiconductor wafer1between the carrier and the processing chamber, and performs a series of processes on the semiconductor wafer1in the processing chamber.

Next, a description will be given of preparation of the chemical liquid14in the chemical liquid temperature control circulation discharge mechanism9. In this example, a desired chemical liquid14is prepared from two stock solutions. A specified amount of first stock solution12is supplied from the first stock solution tank9bto the chemical liquid circulation tank9a, and a specified amount of second stock solution13is supplied from the second stock solution tank9cto the chemical liquid circulation tank9a. The chemical liquid circulation pump9dis actuated to circulate the chemical liquid14, and the chemical liquid temperature controller9econtrols a temperature of the chemical liquid14to a predetermined temperature while the chemical liquid14keeps being circulated. When a circulation flow rate and the temperature of the chemical liquid14fall within predetermined ranges, the preparation of the chemical liquid14is completed. Note that an operation of additionally supplying the first stock solution12and the second stock solution13to compensate for a decrease in liquid components caused by volatilization, decomposition and reaction, and a decrease in liquid volume due to the use of the chemical liquid14is generally performed.

Next, a description will be given of an operation of the processing chamber. Rotating the chuck pin base3aof the chuck opening and closing mechanism3to open and close the chuck pin3bwith the ambient temperature gas16passing through the gas heating apparatus11asupplied from the lower surface gas nozzle2callows the semiconductor wafer1to be placed on the chuck stage2bof the stage rotation mechanism2. The ambient temperature gas16serves to hold the semiconductor wafer1by the Bernoulli effect. Causing the stage rotation motor2ato rotate the chuck stage2ballows the semiconductor wafer1held by the chuck pin3bto rotate. The chemical liquid nozzle6is attached to the chemical liquid nozzle scan mechanism7, and the scan motor7aoscillates to allow the chemical liquid nozzle6to perform a scan on the upper surface of the semiconductor wafer1via the scan shaft7band the scan arm7c. The chemical liquid process is performed by discharging the chemical liquid14at a predetermined flow rate while rotating the semiconductor wafer1at a predetermined rotation speed and causing the chemical liquid nozzle6to perform a scan at a predetermined speed so as to cause the chemical liquid14aon the upper surface of the semiconductor wafer1to uniformly spread all over the upper surface of the semiconductor wafer1.

Although the rotation of the semiconductor wafer1causes the chemical liquid14aon the upper surface of the semiconductor wafer1to flow out from an end portion of the semiconductor wafer1, with the first cup5aof the cup lift mechanism5disposed to surround a periphery of the chuck stage2blifted, the chemical liquid14abecomes a reclaimed chemical liquid14band returns to the chemical liquid circulation tank9athrough the first gas-liquid separator10a.

During the execution of the chemical liquid process, in order to prevent the chemical liquid14aon the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to a lower surface due to surface tension and further to suppress a temperature change in an area around the center portion of the semiconductor wafer1, the temperature-controlled gas17whose temperature has been controlled by the gas heating apparatus11ato a predetermined temperature appropriate to the chemical liquid temperature is supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b. The temperature-controlled gas17serves to hold the semiconductor wafer1by the Bernoulli effect. This makes it possible to ensure sufficient in-plane uniformity in the chemical liquid process. Temperature-controlled gas17aon the lower surface of the semiconductor wafer1is exhausted by the first cup5atogether with an atmosphere on the upper surface of the semiconductor wafer1and then becomes temperature-controlled gas17bto be released through the first gas-liquid separator10a.

When the chemical liquid process is completed, the discharge of the chemical liquid14is stopped, the chemical liquid nozzle scan mechanism7is returned to a standby position, the second cup5bis lifted, and the water washing process is started.

FIG.7is a cross-sectional view showing the water washing process in the processing chamber. As shown inFIG.7, the water washing process is performed by discharging the water15from the water nozzle8to the center portion of the semiconductor wafer1at a predetermined flow rate while rotating the semiconductor wafer1at a predetermined rotation speed so as to cause the water15to uniformly spread all over the upper surface of the semiconductor wafer1.

During the execution of the water washing process, in order to prevent the water15aon the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension, the ambient temperature gas16passing through the gas heating apparatus11ais supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b. The ambient temperature gas16serves to hold the semiconductor wafer1by the Bernoulli effect.

Note that the amount of heat conducted from the semiconductor wafer1to water15ais large during the execution of the water washing process, so that high-temperature gas during the conversion of the temperature-controlled gas17to the ambient temperature gas16is acceptable in most cases, and there is no problem even when the temperature-controlled gas17remains as it is in consideration of the next drying process. Similarly, the temperature-controlled gas17serves to hold the semiconductor wafer1by the Bernoulli effect.

Ambient temperature gas16aon the lower surface of the semiconductor wafer1is exhausted by the second cup5btogether with the atmosphere on the upper surface of the semiconductor wafer1and then becomes ambient temperature gas16bto be released through a second gas-liquid separator10b. At this time, water15bis drained from the second gas-liquid separator10b. When the water washing process is completed, the discharge of the water15is stopped, and the drying process is started.

FIG.8is a cross-sectional view showing the drying process in the processing chamber. As shown inFIG.8, rotating the semiconductor wafer1at a predetermined rotation speed causes the semiconductor wafer1to be spin-dried.

During the execution of the drying process, in order to prevent the water15a(seeFIG.7) on the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension and droplets splashing off the second cup5bfrom moving to the lower surface and to further accelerate the drying of the semiconductor wafer1, the temperature-controlled gas17whose temperature has been controlled by the gas heating apparatus11ato a predetermined temperature suitable for the drying is supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b. The temperature-controlled gas17serves to hold the semiconductor wafer1by the Bernoulli effect.

The supply of the temperature-controlled gas17whose temperature is higher than the ambient temperature heats the semiconductor wafer1to allow a drying time to be shortened.

The temperature-controlled gas17aon the lower surface of the semiconductor wafer1is exhausted by the second cup5btogether with the atmosphere on the upper surface of the semiconductor wafer1and then becomes the temperature-controlled gas17bto be released through the second gas-liquid separator10b.

FIG.9is a flowchart showing processes to be performed in the semiconductor manufacturing apparatus according to the first preferred embodiment.

As shown inFIG.9, a wafer holding process includes steps S201to S206, a wafer processing process includes steps S207to S209, a water washing and drying process includes steps S210to S212, and a wafer ejecting process includes steps S213to S217.

The PLC102acauses a robot hand of the transfer robot to eject, from the carrier, the semiconductor wafer1stored in the carrier in step S201, and rotates the chuck pin base3ato open the chuck pin3bin step S202.

The PLC102apositions the robot hand at a delivery position over the chuck stage2bin step S203, and causes the robot hand to deliver the semiconductor wafer1to the chuck stage2bwith the ambient temperature gas supplied to the lower surface of the semiconductor wafer1in step S204.

The PLC102arotates the chuck pin base3ato close the chuck pin3bin step S205, moves the robot hand outside the processing chamber in step S206, and lifts the first cup5ain step S207.

The PLC102aperforms, in step S208, the chemical liquid process by discharging the chemical liquid14at the predetermined flow rate while rotating the semiconductor wafer1at the predetermined rotation speed and causing the chemical liquid nozzle6to perform a scan at the predetermined speed so as to cause the chemical liquid14aon the upper surface of the semiconductor wafer1to uniformly spread all over the upper surface of the semiconductor wafer1as described above. During the execution of the chemical liquid process, in order to prevent the chemical liquid14aon the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension and further to suppress a temperature change in an area around the center portion of the semiconductor wafer1, the temperature-controlled gas17whose temperature has been controlled by the gas heating apparatus11ato a predetermined temperature appropriate to the chemical liquid temperature is supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b.

The PLC102alifts the second cup5bin step S209, and performs, in step S210, the water washing process by discharging the water15from the water nozzle8to the center portion of the semiconductor wafer1at the predetermined flow rate while rotating the semiconductor wafer1at the predetermined rotation speed so as to cause the water15to uniformly spread all over the upper surface of the semiconductor wafer1as described above. During the execution of the water washing process, in order to prevent the water on the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension, the ambient temperature gas16passing through the gas heating apparatus11ais supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b.

Note that the amount of heat conducted from the semiconductor wafer1to the water15ais large during the execution of the water washing process, so that high-temperature gas during the conversion of the temperature-controlled gas17to the ambient temperature gas16is acceptable in most cases, and there is no problem even when the temperature-controlled gas17remains as it is in consideration of the next drying process.

The PLC102arotates the semiconductor wafer1at the predetermined rotation speed to spin-dry the semiconductor wafer1in step S211. During the execution of the drying process, in order to prevent the water15aon the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension and droplets splashing off the second cup5bfrom moving to the lower surface and to further accelerate the drying of the semiconductor wafer1, the temperature-controlled gas17whose temperature has been controlled by the gas heating apparatus11ato a predetermined temperature suitable for the drying is supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2b.

The PLC102alowers the first cup5aand the second cup5band supplies the ambient temperature gas16passing through the gas heating apparatus11afrom the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2bin step S212, and positions the robot hand at the delivery position in step S213.

The PLC102arotates the chuck pin base3ato open the chuck pin3bin step S214, and causes the robot hand to take the semiconductor wafer1from the chuck stage2band stops the ambient temperature gas16being supplied from the lower surface gas nozzle2cpositioned in alignment with the center portion of the chuck stage2bin step S215.

The PLC102acauses the robot hand to store the semiconductor wafer1into the carrier in step S216, and rotates the chuck pin base3ato close the chuck pin3bin step S217.

In steps S204to S215, the ambient temperature gas16or the temperature-controlled gas17is supplied to hold the semiconductor wafer1by the Bernoulli effect.

The response when heating gas is required to allow the ambient temperature gas16to be supplied as the temperature-controlled gas17during a period from the holding of the semiconductor wafer1to the start of the chemical liquid process, and there is no problem as long as the response is, for example, 20 seconds or less.

The response when cooling gas is required to lower the temperature of the semiconductor wafer1to a temperature that does not affect the transfer during a period from the drying of the semiconductor wafer1to the ejecting of the semiconductor wafer1, and, for example, when the temperature that does not affect the transfer is 60° C., sufficient drying performance can be obtained even when the semiconductor wafer1is dried with temperature-controlled gas having 80° C. or lower in order to achieve a response of 30 seconds or less.

Note that, although the steps have been described roughly sequentially for the purpose of simplification, it is needless to say that segmented operation steps are practically in execution in parallel, and various inputs and outputs related to the operations are in execution.

As described above, in the gas heating apparatus11aaccording to the first preferred embodiment, the induction coil57is disposed in parallel with the heating element51on the lower surface of the heat-resistant enclosure54, so that the magnetic flux distribution of the induction coil57becomes uniform and optimized. This allows the temperature of the heating element51during heating or cooling to be uniform.

Furthermore, the heating element51having a flat plate shape is disposed, with a gap provided around the heating element51, in the space54ihaving a flat plate shape as with the heating element51, so that the gap around the heating element51becomes uniform. This allows the gas passing through the space54iof the heat-resistant enclosure54to be uniformly heated or cooled. As described above, gas having a desired temperature can be stably obtained without increasing the thermal capacity of the heating element51or increasing the area of the heating element51, so that it is possible to improve the response when heating or cooling the gas.

Further, making the temperature of the heating element51uniform during heating or cooling can prevent the heating element51from being partially heated to a high temperature, so that it is possible to prevent the heating element51from melting and fulfill gas heating with a long life and no contamination.

Further, in the semiconductor manufacturing apparatus, the process is performed while controlling the temperature of the gas flowing out from the gas heating apparatus11ato a temperature set for each step of the recipe corresponding to the process by controlling the electric power supplied to the induction coil57of the gas heating apparatus11a.

This makes the response when the gas heating apparatus11aheats or cools the gas faster and eliminates the need of preparing a plurality of supply systems and selecting a supply system from among the plurality of supply systems for each temperature so as to selectively use gases having different temperatures during the execution of the process, thereby making the structure of the supply system simple.

Further, the temperature of the gas is controlled to a temperature set for each step of the recipe of the process, so that it is possible to heat, without difficulty, the gas to a constant temperature, for example, only during the execution of the chemical liquid process such as an etching process, a removal process, or the like for about 1 minute.

Further, a Bernoulli chuck mechanism is used as means for holding the semiconductor wafer1in the related art, but the flow rate of used gas is high, so that the use of gases having different temperatures in the process performed on the semiconductor wafer1at a predetermined chemical liquid temperature deteriorates the uniformity of the process. According to the first preferred embodiment, however, the gas is supplied to the surface opposed to the processing surface of the semiconductor wafer1in order to hold the semiconductor wafer1, so that adjusting the temperature of the gas to the process temperature of the semiconductor wafer1improves the uniformity of the process.

Further, the gas used in the process performed on the processing surface of the semiconductor wafer1is supplied to the surface opposed to the processing surface of the semiconductor wafer1in order to prevent the chemical liquid discharged from the chemical liquid nozzle6from flowing around to the surface opposed to the processing surface of the semiconductor wafer1.

Examples of the gas supplied to the surface opposed to the processing surface of the semiconductor wafer1include a seal gas for preventing the chemical liquid discharged to the processing surface of the semiconductor wafer1from flowing around to a lower surface of a bevel portion. When the semiconductor wafer1is processed at a predetermined chemical liquid temperature, the use of gases having different temperatures as the seal gas deteriorates the uniformity of the process.

On the other hand, according to the first preferred embodiment, the temperature of the gas is adjusted by the gas heating apparatus11a, so that setting the temperature of the gas to the process temperature of the semiconductor wafer1improves the uniformity of the process.

As shown inFIG.2, the heating element51has the first main surface and the second main surface opposed to the first main surface and is provided with the plurality of through holes51a2passing through from the first main surface to the second main surface. This causes gas passing along the upper surface of the heating element51having a flat plate shape and gas passing along the lower surface of the heating element51to pass through the through holes51a2to come into contact with each other to generate a turbulent flow, thereby allowing nearby gas to be agitated and allowing the temperature to become uniform.

Further, as shown inFIG.3, the heating element51has the first main surface and the second main surface opposed to the first main surface and is provided with the plurality of irregularities over the first main surface and the second main surface. This causes gas passing along the upper surface of the heating element51having a flat plate shape and gas passing along the lower surface of the heating element51to pass through the plurality of irregularities to generate a turbulent flow on both the upper surface and the lower surface, thereby allowing nearby gas to be agitated and allowing the temperature to become uniform.

Second Preferred Embodiment

Next, a description will be given of a semiconductor manufacturing apparatus according to a second preferred embodiment.FIG.10is a cross-sectional view showing a chemical liquid process in a processing chamber of the semiconductor manufacturing apparatus according to the second preferred embodiment. Note that, in the second preferred embodiment, the same components as those described in the first preferred embodiment are denoted by the same reference numerals, and descriptions thereof will be omitted.

As shown inFIG.10, the semiconductor manufacturing apparatus includes a stage rotation mechanism2, a platen4, a cup lift mechanism5, a chemical liquid nozzle6, a chemical liquid nozzle scan mechanism7, a water nozzle8, a chemical liquid temperature control circulation discharge mechanism9, a first gas-liquid separator10a, an on-off valve18, and a lower surface gas temperature control discharge mechanism20.

According to the first preferred embodiment, the semiconductor manufacturing apparatus includes the chuck opening and closing mechanism3that holds the semiconductor wafer1from the side surface of the semiconductor wafer1using the chuck pin3b. On the other hand, according to the second preferred embodiment, the stage rotation mechanism2includes a suction chuck stage2dthat draws the lower surface of the semiconductor wafer1to hold the semiconductor wafer1and is not configured to supply the temperature-controlled gas from the center portion to the outer periphery of the lower surface of the semiconductor wafer1.

Further, according to the second preferred embodiment, the semiconductor manufacturing apparatus includes the lower surface gas temperature control discharge mechanism20instead of the lower surface gas temperature control discharge mechanism11. The lower surface gas temperature control discharge mechanism20includes a gas heating apparatus20aand an on-off valve20b. The on-off valve20bis disposed adjacent to an inlet of the gas heating apparatus20a. Note that the gas heating apparatus20ais the same in configuration as the gas heating apparatus11a.

Controlling electric power supplied to an induction coil57of the gas heating apparatus20acontrols a temperature of gas flowing out from the gas heating apparatus20a. Specifically, the gas heating apparatus20ais controlled on the basis of the electric power supplied to the induction coil57to heat or cool the gas to a temperature set for each step of a recipe corresponding to the process performed on the processing surface of the semiconductor wafer1.

With the electric power supplied to the induction coil57, opening the on-off valve20bchanges ambient temperature gas21to temperature-controlled by the gas heating apparatus20ato become temperature-controlled gas22and supplied to the lower surface gas nozzle2e. On the other hand, with no electric power supplied to the induction coil57, opening the on-off valve20bcauses the ambient temperature gas21to pass through the gas heating apparatus20awithout being temperature-controlled by the gas heating apparatus20aand supplied to the lower surface gas nozzle2eas it is. The lower surface gas nozzle2eis a nozzle for supplying the gas flowing out from the gas heating apparatus20ato the semiconductor wafer1during the execution of the process on the processing surface of the semiconductor wafer1. Herein, the process that is associated with the lower surface gas nozzle2eand is performed on the processing surface of the semiconductor wafer1includes a chemical liquid process, a water washing process, and a drying process performed in the processing chamber.

When a vacuum19produced by the on-off valve18acts on the suction chuck stage2d, the center portion of the lower surface of the semiconductor wafer1is brought into close contact with the suction chuck stage2d.

Therefore, during the execution of the chemical liquid process, in order to prevent the chemical liquid14aon the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension, the temperature-controlled gas22whose temperature has been controlled by the gas heating apparatus20ato a predetermined temperature appropriate to the chemical liquid temperature is supplied from the lower surface gas nozzle2ehaving a ring shape and positioned outside the suction chuck stage2d.

This makes it possible to ensure sufficient in-plane uniformity in the chemical liquid process. Temperature-controlled gas22aon the lower surface of the semiconductor wafer1is exhausted by the first cup5atogether with an atmosphere on the upper surface of the semiconductor wafer1and then becomes temperature-controlled gas22bto be released through the first gas-liquid separator10a.

When the chemical liquid process is completed, the discharge of the chemical liquid14is stopped, the chemical liquid nozzle scan mechanism7is returned to a standby position, the second cup5bis lifted, and the water washing process is started.

During the execution of the water washing process, in order to prevent the water15a(seeFIG.7) on the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension, the ambient temperature gas21passing through the gas heating apparatus20ais supplied from the lower surface gas nozzle2ehaving a ring shape and positioned outside the suction chuck stage2d.

Note that the amount of heat conducted from the semiconductor wafer1to the water15ais large during the execution of the water washing process, so that high-temperature gas during the conversion of the temperature-controlled gas22to the ambient temperature gas21is acceptable in most cases, and there is no problem even when the temperature-controlled gas22remains as it is in consideration of the next drying process.

During the execution of the drying process, in order to prevent the water15a(seeFIG.7) on the upper surface of the semiconductor wafer1from flowing along the end portion of the semiconductor wafer1to the lower surface due to surface tension and droplets splashing off the second cup5bfrom moving to the lower surface and to further accelerate the drying of the semiconductor wafer1, the temperature-controlled gas22whose temperature has been controlled by the gas heating apparatus20ato a predetermined temperature suitable for the drying is supplied from the lower surface gas nozzle2ehaving a ring shape and positioned outside the suction chuck stage2d.

The supply of the temperature-controlled gas22whose temperature is higher than the ambient temperature heats the semiconductor wafer1to allow a drying time to be shortened.

The temperature-controlled gas22aon the lower surface of the semiconductor wafer1is exhausted by the second cup5btogether with the atmosphere on the upper surface of the semiconductor wafer1and then becomes the temperature-controlled gas22bto be released through the second gas-liquid separator10b.

As described above, the semiconductor manufacturing apparatus according to the second preferred embodiment allows an improvement in response when heating or cooling the gas as in the first preferred embodiment. Further, making the response when the gas heating apparatus20aheats or cools the gas faster eliminates the need of preparing a plurality of supply systems and selecting a supply system from among the plurality of supply systems for each temperature so as to selectively use gases having different temperatures during the execution of the process, thereby making the structure of the supply system simple.

Further, as in the first preferred embodiment, the gas used in the process performed on the processing surface of the semiconductor wafer1is supplied to the surface opposed to the processing surface of the semiconductor wafer1in order to prevent the chemical liquid discharged from the chemical liquid nozzle6from flowing around to the surface opposed to the processing surface of the semiconductor wafer1. The temperature of the gas is adjusted by the gas heating apparatus20a, so that setting the temperature of the gas to the process temperature of the semiconductor wafer1improves the uniformity of the process.

Third Preferred Embodiment

Next, a description will be given of a semiconductor manufacturing apparatus according to a third preferred embodiment.FIG.11is a cross-sectional view showing a chemical liquid process in a processing chamber of the semiconductor manufacturing apparatus according to the third preferred embodiment. Note that, in the third preferred embodiment, the same components as those described in the first and second preferred embodiments are denoted by the same reference numerals, and descriptions thereof will be omitted.

As shown inFIG.11, the semiconductor manufacturing apparatus includes a stage rotation mechanism2, a chuck opening and closing mechanism3, a platen4, a cup lift mechanism5, a two-fluid chemical liquid nozzle6a, a chemical liquid nozzle scan mechanism7, a water nozzle8, a chemical liquid temperature control circulation discharge mechanism9, a first gas-liquid separator10a, a lower surface gas temperature control discharge mechanism11, and a chemical liquid gas temperature control discharge mechanism23.

According to the third preferred embodiment, the semiconductor manufacturing apparatus includes, instead of the chemical liquid nozzle6, the two-fluid chemical liquid nozzle6athat discharges a mixture of a chemical liquid and a gas used in the process performed on the processing surface of the semiconductor wafer1.

The chemical liquid gas temperature control discharge mechanism23includes a gas heating apparatus23aand an on-off valve23b. The on-off valve23bis disposed adjacent to an inlet of the gas heating apparatus23a. Note that the gas heating apparatus23ais the same in configuration as the gas heating apparatus11a.

Controlling electric power supplied to an induction coil57of the gas heating apparatus23acontrols a temperature of gas flowing out from the gas heating apparatus23a. Specifically, the gas heating apparatus23ais controlled on the basis of the electric power supplied to the induction coil57to heat or cool the gas to a temperature set for each step of a recipe corresponding to the process performed on the processing surface of the semiconductor wafer1.

With the electric power supplied to the induction coil57, opening the on-off valve23bchanges ambient temperature gas24to temperature-controlled by the gas heating apparatus23ato become temperature-controlled gas25and supplied to the two-fluid chemical liquid nozzle6a. On the other hand, with no electric power supplied to the induction coil57, opening the on-off valve23bcauses the ambient temperature gas24to pass through the gas heating apparatus23awithout being temperature-controlled by the gas heating apparatus23aand supplied to the two-fluid chemical liquid nozzle6aas it is. The two-fluid chemical liquid nozzle6ais a nozzle for supplying the gas flowing out from the gas heating apparatus23ato the semiconductor wafer1during the execution of the process on the processing surface of the semiconductor wafer1. Herein, the process that is associated with the two-fluid chemical liquid nozzle6aand is performed on the processing surface of the semiconductor wafer1includes a chemical liquid process performed in the processing chamber.

When the semiconductor wafer1is processed at a predetermined chemical liquid temperature, it is necessary for the two-fluid chemical liquid nozzle6ato mix gas having a temperature substantially equal to or higher than the chemical liquid temperature with the chemical liquid in order to increase the strength of cleaning, and heating or cooling means with high responsivity is indispensable. The flow rate of the gas used in the two-fluid chemical liquid nozzle6ais about one quarter of the flow rate during the wafer holding described in the first preferred embodiment. Therefore, even when the gas heating apparatus23ahaving the same configuration as in the first preferred embodiment is used, the response when heating gas is as short as about one half of the response in the first preferred embodiment, and it is therefore possible to cope with a case where the supply of electric power is enabled or disabled for each process on the semiconductor wafer1without difficulty. This eliminates the need of supplying, without interruption, the temperature-controlled gas25to the two-fluid chemical liquid nozzle6a.

As described above, the semiconductor manufacturing apparatus according to the third preferred embodiment allows an improvement in response when heating or cooling the gas as in the first preferred embodiment.

Further, the gas used in the process performed on the processing surface of the semiconductor wafer1is mixed with the chemical liquid and discharged from the two-fluid chemical liquid nozzle6ato the processing surface of the semiconductor wafer1, so that it is possible to increase the strength of cleaning of the processing surface of the semiconductor wafer1.

Note that the present disclosure can be implemented by any combination of the preferred embodiments, and each of the preferred embodiments can be modified or omitted as appropriate.

While the disclosure has been shown and described in detail, the foregoing description is in all aspects illustrative and not restrictive. It is therefore understood that numerous modifications and variations can be devised.