JP6211886B2 - Heat treatment method and heat treatment apparatus - Google Patents

Description

  The present invention relates to a substrate heat treatment method and a heat treatment apparatus.

  In the semiconductor manufacturing process, for example, a photolithography process is performed in which a photoresist is applied on a substrate such as a semiconductor wafer, the resist film is exposed according to a predetermined circuit pattern, and developed to form a circuit pattern. . In this photolithography process, heat treatment is performed after applying a photoresist coating solution or after exposure. The heat treatment is also performed in the step of forming an antireflection film on the substrate before and after the photoresist coating step and in the step of forming a coating film such as an SOG material or a dopant material on a glass substrate or the like.

  In the heat treatment in the coating film forming step, the heat treatment may be performed by changing the heat treatment temperature stepwise. For example, in Patent Document 1, in the formation of an antireflection film, a substrate is first heated close to the low-temperature side heat treatment plate, and then the substrate is moved close to the high-temperature side heat treatment plate and heated stepwise. Is described. In Patent Document 2 and Patent Document 3, when a silica-based coating forming coating solution such as an SOG material or a color resist is heat-treated, the substrate is first heated in a state where the substrate is held by lift pins, and then the substrate is mounted on a heat treatment plate. A method is described in which the heat treatment temperature is increased stepwise by heating in the state of being placed.

  On the other hand, as a result of the research, the present inventor conducted heat treatment at a low temperature while holding the substrate on the lift pins, and then placed on a heat treatment plate and performed high temperature heating, dry particles adhered to the substrate Found that the risk of doing so increases. The reason for this is that since the inside of the heat treatment apparatus is in a high temperature atmosphere, the particles existing inside the apparatus are in a high energy state, and when a substrate at room temperature (23 ° C.) is carried in, the energy balance is achieved. It is considered that particles are likely to adhere to the substrate by thermophoresis.

  However, the adhesion of dry particles to the substrate in the two-stage heat treatment is not considered in any of the above-mentioned patent documents.

JP 2000-91218 A (Claims, FIG. 4) JP-A-11-97324 (Claims, FIG. 1) JP 2010-79217 A (Claims, FIG. 4)

  The present invention has been made in view of the above circumstances, and provides a heat treatment method and a heat treatment apparatus capable of suppressing the adhesion of dry particles to a substrate in a method of heat-treating a substrate stepwise. For the purpose.

In order to solve the above-described problems, the heat treatment method of the present invention is a method of heat-treating a substrate in stages at different treatment temperatures, and includes a substrate carry-in process for carrying the substrate into the heat treatment apparatus, A preparatory step of raising the temperature of the carried-in substrate to the first temperature, and a first heating step of heat-treating the substrate at a second temperature at a position separated from the heat treatment plate in the heat treatment apparatus by a certain distance; Next, a second heating step of placing the substrate on the heat treatment plate and heat-treating at a third temperature, and the preparing step includes treating the substrate carried into the heat treatment apparatus with the heat treatment plate. The temperature of the substrate is raised to the same temperature as the second temperature or a first temperature lower than the second temperature by placing the substrate on the first heating step and the first temperature. When the processing time in the heating process of 2 is shorter Wherein the carried out that at.

  Note that in the preparation step, rapidly increasing the temperature of the substrate means increasing the temperature of the substrate at a heating rate faster than the heating rate of the substrate in the first heating step.

A storage medium according to the present invention is a storage medium that stores a computer program used in a heat treatment apparatus that heat-treats a substrate on which a coating film is formed. The computer program executes the heat treatment method described above. As described above, a step group is incorporated.

A heat treatment apparatus according to the present invention is disposed in a heat treatment apparatus, a heat treatment plate on which a substrate is placed and performs heat treatment, and a substrate carried into the heat treatment apparatus at a raised position spaced apart from the heat treatment plate by a certain distance. And a control unit that controls the temperature of the heat treatment plate and the raising and lowering of the support mechanism. The control unit includes the heat treatment apparatus. The temperature of the substrate carried into the substrate is raised to the first temperature (preparation step), and then heat-treated at the second temperature at a position where the substrate is separated from the heat treatment plate in the heat treatment apparatus by a certain distance ( Next, the substrate is placed on the heat treatment plate and heated at a third temperature (second heating step), and the preparatory step is carried into the heat treatment apparatus. Place the substrate on the heat treatment plate In the is intended to raise the temperature of the substrate to a first temperature at the same temperature or the second temperature a temperature lower than said second temperature, the first heating step and the second heating step The heat treatment plate and the support mechanism are controlled so as to be performed in a time shorter than the treatment time.

  According to the heat treatment method and the heat treatment apparatus according to the present invention, after the wafer is carried into the heat treatment apparatus, the wafer temperature is quickly increased to a temperature at which adhesion of dry particles can be suppressed. Stepwise heat treatment can be performed without adhering dry particles.

1 is a schematic plan view showing a coating and developing treatment apparatus including a heat treatment apparatus according to the present invention. It is a schematic perspective view which shows the said application | coating development processing apparatus. It is a schematic longitudinal cross-sectional view which shows the said coating and developing processing apparatus. 1 is a schematic sectional side view showing a heat treatment apparatus according to a first embodiment of the present invention. It is the schematic of the control apparatus which concerns on 1st Embodiment of this invention. It is a flowchart of the heat processing method which concerns on this invention. It is a schematic longitudinal cross-sectional view which shows the heat processing method using the heat processing apparatus which concerns on 1st Embodiment of this invention in steps. It is a schematic sectional side view which shows the heat processing apparatus which concerns on 2nd Embodiment of this invention. It is a schematic longitudinal cross-sectional view which shows the heat processing method using the heat processing apparatus which concerns on 2nd Embodiment of this invention in steps. It is a graph which shows the result of the evaluation regarding the wafer temperature performed about the effect of this invention, and the adhesion number of a particle. It is a graph which shows the result of the evaluation performed in order to investigate the temperature rising transient history of a wafer.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, the structure and operation of a coating and developing treatment apparatus to which a heat treatment method and a heat treatment apparatus according to the present invention are applied will be described.

  As shown in FIG. 1, a carrier block S1, a processing block S2, an interface block S3, and an exposure block S4 are connected to the coating and developing treatment apparatus 1 in this order from the carrier block S1 to the exposure block S4.

  In the carrier block S1, the transport mechanism C takes out the wafer W (substrate) from the sealed carrier 11 placed on the placement table 10, and transfers it to the processing block S2 adjacent to the carrier block S1. Further, the transfer mechanism C is configured to receive the wafer W after being processed in the processing block S <b> 2 and return it to the carrier 11.

  As shown in FIG. 2, the processing block S2 includes a first block (DEV layer) B1 for performing development processing, and a second block (BCT layer) for forming an antireflection film on the lower layer side of the resist film. B2, a third block (COT layer) B3 for applying the resist solution, and a fourth block (TCT layer) B4 for forming an antireflection film on the upper side of the resist film are stacked in order from the bottom. Configured.

  The second block (BCT layer) B2 and the fourth block (TCT layer) B4 each include a liquid processing module 30 including three application portions for applying a chemical solution for forming an antireflection film by spin coating. And a heating / cooling processing module 40 for performing pre-processing and post-processing of the processing performed in the liquid processing module 30, the liquid processing module 30, and the heating / cooling processing module 40. Are provided with transfer mechanisms A2 and A4 which are substrate transfer means for transferring the wafer W between them (see FIG. 3).

  The third block (COT layer) B3 has the same configuration as the BCT layer B2 and the TCT layer B4 except that the chemical solution is a resist solution and a hydrophobic treatment unit is incorporated. On the other hand, for the first processing block (DEV layer) B1, for example, development units are stacked in two stages in one DEV layer B1. In the DEV layer B1, a common transport mechanism A1 for transporting the wafer W to these two development units is provided (see FIG. 3). Further, as shown in FIG. 1 and FIG. 3, the processing block S2 is provided with a shelf unit U5 on the carrier block S1 side, and between the parts of the shelf unit U5, the lifting / lowering provided in the vicinity of the shelf unit U5. The wafer W is transferred by a free transfer mechanism E. Further, a shelf unit U6 is provided on the interface block S3 side of the processing block S2.

  On the other hand, in the upper part of the DEV layer B1, a shuttle arm F which is a dedicated transfer means for directly transferring the wafer W from the transfer unit CPL11 provided in the shelf unit U5 to the transfer unit CPL12 provided in the shelf unit U6. Is provided (see FIG. 3). The wafer W on which the resist film and further the antireflection film are formed is transferred to the transfer unit CPL11 by the transfer mechanism E via the transfer units BF3 and TRS4, and from here to the transfer unit CPL12 of the shelf unit U6 by the shuttle arm F directly. Be transported.

  Next, the wafer W is transferred to the exposure block S4 by the interface arm I, where a predetermined exposure process is performed, and then placed on the transfer unit TRS6 of the shelf unit U6 and returned to the processing block S2. The returned wafer W is developed in the first block (DEV layer) B1, and transferred to the transfer unit TRS3 by the transfer mechanism A1 serving as the substrate transfer means (see FIG. 3).

  Thereafter, it is returned to the carrier 11 via the transport mechanism C. In FIG. 1, heating / cooling processing modules 40 are stacked on the shelf units U1 to U4. The heat treatment apparatus 50 according to the present invention is provided, for example, in the shelf unit U4.

  Next, the configuration and operation of the heat treatment apparatus 50 according to the present invention will be described in detail. The heat treatment apparatus 50 according to the present invention is used, for example, when heat-treating a substrate after applying a treatment liquid in forming a resist film or an antireflection film.

<First Embodiment>
As shown in FIG. 4, the heat treatment apparatus according to the first embodiment includes a lid body 60 and a heat treatment plate accommodation portion 61 inside a housing 51. The lid body 60 is located above the heat treatment plate accommodation portion 61 and can move up and down, and forms a processing space S together with the heat treatment plate accommodation portion 61.

  A loading / unloading port 52 for loading / unloading the wafer W into / from the heat treatment apparatus 50 is provided on a side surface of the casing 51, and a shutter 53 that can open and close the loading / unloading port 52 is attached. By closing the shutter 53 except when the substrate is carried in and out, the thermal influence from the heat treatment apparatus 50 is prevented from reaching other treatment apparatuses.

  The lid 60 has a substantially cylindrical shape with an open lower surface so as to surround the wafer W. When the wafer W is carried into the heat treatment apparatus 50, the lid body 60 rises to an upper position and then descends to form a treatment space S together with the heat treatment plate accommodating portion 61 during the heat treatment.

An exhaust pipe 62 is connected to the center of the upper surface of the lid 60. The exhaust pipe 62 extends through the housing 51 to the outside of the heat treatment apparatus 50 and is connected to the suction apparatus 64 via the filter 63. By operating the suction device 64, the atmosphere of the processing space S can be discharged to the outside of the heat processing apparatus 50. The suction device 64 includes a control unit 65 that controls the exhaust amount. Further, the exhaust pipe 62 is flexible and has a configuration that does not affect the exhaust amount even if the lid body 60 moves up and down. The filter 63 collects impurities contained in the exhaust and prevents the impurities from flowing to the suction device 64 side.

  An LED 66 as a light source is provided on the ceiling portion 60 a inside the upper surface of the lid 60. The LED 66 is connected to a control unit 68 that controls light irradiation via a cable 67. A plurality of LEDs 66 are arranged on the ceiling 60 a so that light can be emitted from above the wafer W while the wafer W carried into the heat treatment apparatus 50 is placed on the support pins 72. The light emitted from the LED 66 is light having a wavelength that does not sensitize the coating film applied to the wafer W.

  A heat treatment plate 69 for placing and heating the wafer W is provided in the heat treatment plate accommodating portion 61. The heat treatment plate 69 is made of a ceramic such as silicon carbide or aluminum nitride, and is formed in a disk shape having a thickness of about 2 to 10 mm.

  A heater 70 serving as a heat source for the heat treatment plate 69 is provided on the back surface of the heat treatment plate 69. The heater 70 is connected to a control unit 71 that controls the heat generation amount of the heater 70, and the control unit 71 controls the heat generation amount of the heater 70 so that the heat treatment plate 69 can be maintained at a predetermined temperature. ing.

  Below the heat treatment plate 69, support pins 72 for supporting the wafer W carried in from the outside at a position above the heat treatment plate 69 are provided. The support pin 72 is provided with an elevating mechanism 73 and can be raised and lowered. The support pins 72 project through the through-holes 74 provided in the heat treatment plate 69 and protrude on the heat treatment plate 69 by the lifting mechanism 73, and can support the wafer W at a position above the heat treatment plate 69. The elevating mechanism 73 elevates and lowers the support pins 72 by controlling the elevating operation from the control unit 75.

  The heat treatment plate accommodating portion 61 further includes a support base 76 that supports the outer edge portion of the heat treatment plate 69. The support base 76 is formed of a heat insulating material so that the heat of the heat treatment plate 69 is not released to the outside.

  Further, the heat treatment plate accommodating portion 61 has a substantially cylindrical support ring 77 so as to surround the outer peripheral portion of the support base 76. The support ring 77 is provided with a blowout port 78 through which a gas such as an inert gas is ejected in the processing space S. By ejecting a gas from the air outlet 78, the inside of the processing space S can be purged with the gas. A cylindrical container 79 is provided so as to surround the outer periphery of the support ring 77, and forms a processing space S together with the lid 60.

  As shown in FIG. 5, the control unit 65 of the suction device 64, the control unit 68 of the LED 66, the control unit 71 of the heater 70, and the control unit 75 of the lifting mechanism 73 are connected to a control computer 80 outside the device. The control computer 80 outside the apparatus is built in the control apparatus 90. The control computer 80 includes a computer-readable storage medium that stores software that causes the control computer 80 to execute a control program, and is configured to output a control signal to each of the units based on the control program. . The control program is stored in a storage medium such as a hard disk, a compact disk, a flash memory, a flexible disk, or a memory card, and is used by being installed in the control computer 80 from these storage media.

  Next, a heat treatment method using the heat treatment apparatus according to this embodiment configured as described above will be described. Below, for convenience of explanation, a heat treatment method of the heat treatment apparatus 50 in the BCT layer B2 will be described.

  First, the wafer W taken out from the carrier 11 shown in FIG. 2 is transferred by the transfer mechanism C to CPL2 of the shelf unit U5. After being cooled to about 23 ° C. by the CPL2, the wafer W is transferred to the liquid processing module 30 of the second block B2 by the transfer mechanism A2, and a chemical solution for forming an antireflection film is applied to the surface (upper surface) of the wafer W. The When the liquid processing in the liquid processing module 30 is completed, the transfer mechanism A2 carries the wafer W out of the liquid processing module 30 and transfers it to the heat treatment apparatus 50.

  On the other hand, in the heat treatment apparatus 50, when the wafer W is not in the heat treatment apparatus 50, the control unit 71 adjusts the heater 70 of the heat treatment plate 69 to adjust the temperature of the heat treatment plate 69 to a predetermined temperature, for example, 400 ° C. Keep waiting.

  Next, the operation of the heat treatment apparatus 50 according to this embodiment will be described with reference to FIGS. 6 and 7A to 7F.

  When the transfer mechanism A2 transfers the wafer W to the heat treatment apparatus 50, the shutter 53 of the loading / unloading port 52 of the heat treatment apparatus 50 is opened, and the transfer mechanism A2 holding the wafer W enters the heat treatment plate 69. . The wafer W carried into the upper part of the heat treatment plate 69 is placed on the support pins 72 (step S1 in FIG. 6, FIG. 7A).

  As shown in FIG. 7B, when the wafer W is placed on the support pins 72, the control unit 68 causes the LED 66 to emit light from the LED 66 to the surface of the wafer W (the upper surface coated with the chemical solution). Control. Thereby, the wafer W is heated to a predetermined temperature, for example, 150 ° C. Thereafter, the support pins 72 and the lid 60 are lowered, and the wafer W is placed on the heat treatment plate 69 via gap pins (not shown) (FIG. 7C). The wafer W is placed on the heat treatment plate 69 for a predetermined time, for example, 5 seconds, the back surface of the wafer W is heated by the heat treatment plate 69, and the wafer W rises to a predetermined temperature (first temperature), for example, 300 ° C. Then, a preparation process is complete | finished (process S2 of FIG. 6).

  When the preparation process is completed, the support pin 72 is lifted (FIG. 7D). Thus, the wafer W is supported by the support pins 72 at a position spaced apart from the heat treatment plate 69 by a certain distance, and the first heating step is performed (step S3 in FIG. 6). At this time, the controller 75 controls the height of the support pins 72 so that the wafer W can be heated at the target temperature (second temperature). The heating target temperature of the wafer W in this embodiment is, for example, 300 ° C. Note that the height of the wafer support portion (not shown) of the support pins 72 from the heat treatment plate 69 is preset based on the set temperature of the heat treatment plate 69 and the heating target temperature of the wafer W. In this embodiment, For example, it is set to 17 mm. In the first heating step, the wafer W is heated at a position spaced apart from the heat treatment plate 69 by a certain distance, for example, for 30 seconds.

  When the first heating step is thus completed, the support pins 72 are lowered again, and the wafer W is placed on the heat treatment plate 69 via gap pins (not shown), and the wafer W is placed at a predetermined temperature (third temperature). ) Is performed (step S4 in FIG. 6). At this time, the heat treatment plate 69 is set to 400 ° C., for example. In the second heating step, for example, the wafer W is heated for 60 seconds (FIG. 7E).

  When the second heating step is completed, the support pins 72 and the lid 60 are raised, the shutter 53 of the loading / unloading port 52 is opened, and the transport mechanism A2 enters the heat treatment apparatus 50 from the loading / unloading port 52 (FIG. 7 ( f)). The wafer W supported by the support pins 72 is received by the transport mechanism A2, and is unloaded from the heat treatment apparatus 50 by the transport mechanism A2. The wafer W unloaded from the heat treatment apparatus 50 is transferred to the BF2 of the shelf unit U5 and proceeds to the subsequent process as described above.

  According to the first embodiment, in the preparation process, the wafer W is heated by the LED 66 and the heat treatment plate 69 immediately after the wafer W is loaded into the heat treatment apparatus 50, and the first preparation process is not performed. The temperature of the wafer W is raised to the first temperature at a heating rate faster than the heating rate of the wafer W in the case where the heating step is performed. As a result, the temperature of the wafer W is increased to a temperature at which the adhesion of dry particles can be suppressed, and thereafter, stepwise heat treatment can be performed without adhering the dry particles to the wafer W.

  In the above embodiment, the wafer W is heated by irradiating the light of the LED 66 after loading the wafer W. However, while the wafer W is loaded, the light of the LED 66 is irradiated and the wafer W is applied to the support pins 72. When placed, the heating by the LED 66 may be terminated. In this case, the LED 66 may be provided at a position adjacent to the loading / unloading port 52, that is, above the peripheral end portion on the loading / unloading port 52 side of the wafer W placed on the support pin 72. When the wafer W passes under the LED 66 provided on the ceiling 60 a of the lid 60, the wafer W receives light from the LED 66 and is heated to a predetermined temperature. When the peripheral end of the wafer W on the loading / unloading exit 52 side passes under the LED 66 when the wafer W is placed on the support pins 72, the heating by the LED 66 ends. As described above, the control unit 68 that controls the irradiation of the LED 66 controls the LED 66 to emit light while the wafer W passes under the LED 66. According to this method, heating by the LED 66 can be performed during the transfer of the wafer W into the heat processing apparatus 50, and the processing time can be shortened. Moreover, it becomes possible to arrange | position LED66 only in the position adjacent to the carrying in / out port 52, and also can anticipate a cost reduction.

  Note that the position of the LED 66 is not limited to the case where it is disposed above the wafer W, and may be disposed below. In this case, the heat treatment plate 69 is formed of a light-transmitting material, the LED 66 is disposed below the heat treatment plate 69, and the wafer W is irradiated with light from below. Thereby, the risk that the coating film is exposed to light from the LED 66 can be suppressed.

  Moreover, in the preparatory process of 1st Embodiment, after heating the wafer W with LED66 and mounting on the heat processing board 69, it heated further, However, You may abbreviate | omit heating of LED66. That is, even after the wafer W loaded into the heat treatment apparatus 50 is placed on the support pins 72, the support pins 72 are immediately lowered, and the wafer W is placed on the heat treatment plate 69 and heated to a predetermined temperature. Good. Also in this case, since the temperature of the wafer W can be quickly raised before the heat treatment, the risk of dry particles in the processing space S adhering to the wafer W can be suppressed.

  Further, the temperature of the wafer W may be raised to the target temperature by heating the LED 66, and subsequent mounting on the heat treatment plate 69 may be omitted. Also in this case, since the temperature of the wafer W can be quickly raised before the heat treatment, the risk that particles in the processing space S adhere to the wafer W can be suppressed.

Second Embodiment
Next, 2nd Embodiment of the heat processing apparatus which concerns on this invention is described with reference to FIG.
The second embodiment is different from the first embodiment in that a heated gas supply unit 160 is provided instead of the LED 66. Below, a different point from 1st Embodiment is demonstrated, the same code | symbol is attached | subjected about the same part, and description is abbreviate | omitted.

  The heated gas supply unit 160 includes a gas supply port 161 provided in the center of the ceiling 60 a of the lid 60, a gas supply source 162, and a gas supply line that communicates the gas supply port 161 and the gas supply source 162. 163. The gas supply source 162 is provided with a flow rate adjustment valve (not shown), and adjusts the gas supply amount when supplying an inert gas such as air or N 2 to the heat treatment apparatus 150. Moreover, the gas supply pipe line 163 has flexibility, and has a configuration that does not affect the gas supply amount even when the lid body 60 moves up and down.

  A heater 164 is provided in the gas supply line 163 downstream of the gas supply source 162. The heater 164 includes two branch pipes (not shown) that branch the gas supply pipe 163 inside, a heating source (not shown) such as a heater, and a switching valve (not shown). In the heater 164, when the gas supplied from the gas supply source 162 is heated, the gas is supplied to the branch pipe connected to the heating source by the switching valve, and the gas is heated by the heating source to supply the gas. Send to mouth 161. Further, when the gas supplied from the gas supply source 162 is not heated and the gas is sent to the gas supply port 161 as it is, the switching valve is switched to a branch line not in contact with the other heating source, and the gas is supplied. To the gas supply port 161.

  The heated gas supply unit 160 further includes a current plate 165 inside the lid 60 below the ceiling 60a. The rectifying plate 165 is, for example, a circular plate provided with a large number of ventilation holes (not shown), and is configured so that the gas supplied from the gas supply port 161 is uniformly blown onto the surface of the wafer W.

  The operation of the gas supply source 162 and the heater 164 of the heated gas supply unit 160 is controlled by the control unit 166. The control unit 166 controls the flow rate adjustment valve of the gas supply source 162 to adjust the amount of gas supplied from the gas supply port 161. In addition, the control unit 166 controls the switching valve of the heater 164 to switch the switching valve to the branch pipe line in contact with the heating source when supplying the heating gas, and when supplying the normal purge gas. Switch to a branch line that is not in contact with the heating source. This control unit 166 is also connected to the control computer 80.

  Further, an exhaust port 170 is provided between the support stand 76 that supports the outer edge of the heat treatment plate 69 and the container 79. An exhaust pipe 171 is connected to the exhaust port 170, and the exhaust pipe 171 is provided with, for example, an exhaust pump 172 as exhaust means.

  Next, operation | movement of the heat processing apparatus 150 in 2nd Embodiment is demonstrated using FIG.6 and FIG.9 (a)-FIG.9 (d).

  When the transport mechanism A2 transports the wafer W to the heat treatment apparatus 150, the shutter 53 of the loading / unloading port 52 of the heat treatment apparatus 150 is opened, and the transport mechanism A2 holding the wafer W enters the heat treatment plate 69. . The wafer W loaded up to the heat treatment plate 69 is placed on the support pins 72 (step S1 in FIG. 6, FIG. 9A).

  As shown in FIG. 9B, when the wafer W is placed on the support pins 72, the lid 60 is lowered. After the lid 60 is lowered, the heated gas blows out from the gas supply port 161. The heated gas blown out is blown to the entire surface (the front surface (the upper surface on which the chemical solution is applied) and the rear surface) of the wafer W that passes through the rectifying plate 165 and is placed on the support pins 72. The heated gas is heated to a predetermined temperature, for example, 400 ° C., and the temperature of the wafer W is increased by blowing the heated gas. When the temperature of the wafer W rises to the heating target temperature (first temperature), for example, 300 ° C., the supply of the heated gas is stopped and the preparation process is completed (step S2 in FIG. 6).

  When the preparation process is completed, the wafer W is heated to a predetermined temperature (second temperature) while being supported by the support pins 72 at a position spaced apart from the heat treatment plate 69 by a certain distance. Is performed (step S3 in FIG. 6). In the first heating step, the wafer W is heated at a position separated from the heat treatment plate 69 by a certain distance, for example, for 30 seconds.

  When the first heating step is thus completed, the support pins 72 are lowered, and the wafer W is placed on the heat treatment plate 69 via gap pins (not shown), and the wafer W is placed at a predetermined temperature (third temperature). A second heating step of heating up to is performed (step S4 in FIG. 6). At this time, the heat treatment plate 69 is set to 400 ° C., for example. In the second heating step, for example, the wafer W is heated for 60 seconds (FIG. 9C).

  When the second heating step is completed, the support pins 72 and the lid 60 are raised, the shutter 53 of the loading / unloading port 52 is opened, and the transport mechanism A2 enters the heat treatment apparatus 50 from the loading / unloading port 52 (FIG. 9 ( d)). The wafer W supported by the support pins 72 is received by the transport mechanism A2, and is unloaded from the heat treatment apparatus 50 by the transport mechanism A2. The wafer W unloaded from the heat treatment apparatus 50 is transferred to the BF2 of the shelf unit U5 and proceeds to the subsequent process.

  In the second embodiment, in the preparation step, after the wafer W is loaded into the heat treatment apparatus 150, the heated gas is blown to the wafer W immediately, and the first heating step is performed without the preparation step. The temperature of the wafer W is raised to the first temperature at a heating rate faster than the heating rate of the wafer W in FIG. As a result, the temperature of the wafer W is increased to a temperature at which the adhesion of dry particles can be suppressed, and thereafter, stepwise heat treatment can be performed without adhering the dry particles to the wafer W.

  In the second embodiment, the heating of the wafer W in the preparation process is performed only by spraying the heating gas. However, after the heating gas is sprayed, the wafer W is placed on the heat treatment plate 69 for a predetermined time. The temperature of W may be increased rapidly.

  Although the present invention has been described above with reference to some embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the matters included in the appended claims. It is.

  For example, the temperature (first temperature) for heating the wafer W in the preparation step may be the same temperature as the temperature (second temperature) for heat-treating the wafer W in the first heating step, and is lower than the second temperature. It may be temperature. Further, in the preparation process, after the wafer W is loaded, the wafer W is heated to the first temperature at a heating rate faster than the heating rate of the wafer W when the first heating process is performed without the preparation process. Although the temperature is raised, the temperature may be raised to the first temperature at a heating rate faster than the average heating rate of the wafer W in the second heating step. In the preparation step, a heat source (light or hot air) may be irradiated toward the surface of the wafer W (chemical solution application surface), or a heat source may be irradiated toward the entire surface of the wafer W. Furthermore, in the preparation step, the wafer W may be heated using a heating device used in the first heating step or the second heating step, and the heating device used in the first heating step or the second heating step; A different heating device may be provided separately to heat the wafer W. Further, the wafer W may be heated by using the same heating device as the first heating step or the second heating step and a different heating device at the same time.

  Moreover, although the above embodiment demonstrated the heat processing in the formation process of an anti-reflective film, this invention is not limited to this, It can apply also to the heat processing in another process. For example, the present invention can also be applied to the formation of a coating film using another chemical solution such as a coating solution for forming a silica-based film such as an SOG material or a color resist. The present invention can also be applied to processes other than coating film formation, for example, heat treatment in a development process.

  In the above embodiment, the case where the heat treatment apparatus and the heat treatment method according to the present invention are applied to a semiconductor wafer has been described. However, other than the semiconductor wafer, for example, an FPD (flat panel display), a mask reticle for a photomask, and the like. This can also be applied to other substrates.

<Evaluation test>
Hereinafter, the evaluation test performed about the effect of this invention is demonstrated.

  The following tests were performed using a heat treatment apparatus in which the LED was omitted from the heat treatment apparatus shown in FIG. 4 and a cooling plate was provided in the apparatus. First, the wafer W was placed on the support pins while the support pins of the heat treatment apparatus were raised, and the support pins were immediately lowered to place the wafer W on the heat treatment plate for a predetermined time. Thereafter, the support pins were raised and waited for 30 seconds in that state, and then the cooling plate in the heat treatment apparatus received the wafer W and cooled it for 12 seconds. Thereafter, the wafer W was taken out from the heat treatment apparatus, and the number of particles adhering to the wafer W was measured. The temperature of the heat treatment plate was 400 ° C., and the temperature of the processing space S was 300 ° C. In measuring the number of particles, particles having a diameter of 60 nm or more are defined as particles.

  The results of this evaluation test are shown as a graph in FIG. The horizontal axis represents the ultimate temperature of the wafer W in the preparation process, and the vertical axis represents the number of particles. Further, FIG. 11 shows a wafer temperature rising transient history. In FIG. 11, the horizontal axis represents the heating time of the wafer W, and the vertical axis represents the wafer temperature.

  From the results shown in FIG. 10, it can be confirmed that the number of particles adhering to the wafer W decreases as the temperature reached by the wafer W in the preparation process increases. As shown in FIG. 11, when the wafer is placed on a hot plate at 400 ° C. for 5 seconds, the temperature of the wafer W rises rapidly to about 300 ° C. after being placed at about 190 ° C. for 10 seconds. However, the slope of the graph becomes gentle thereafter, and it takes 60 seconds to reach 400 ° C. Therefore, from the viewpoint of throughput, it is desirable that the heating of the wafer W in the preparation process be performed during a time when the slope of the graph of FIG. 11 is steep.

50, 150 Heat treatment device 60 Lid 61 Heat treatment plate housing 62 Exhaust pipe 66 LED
69 Heat treatment plate
DESCRIPTION OF SYMBOLS 70 Heater 72 Support pin 76 Support stand 79 Container 80 Control computer 90 Control apparatus 160 Heating gas supply part 162 Gas supply source 164 Heater 165 Current plate
170 Exhaust port 171 Exhaust pipe line 172 Exhaust pump

Claims (4)

A method of heating a substrate in stages at different processing temperatures,
A substrate carrying-in step of carrying the substrate into a heat treatment apparatus;
A preparation step of raising the temperature of the substrate carried into the heat treatment apparatus to a first temperature;
A first heating step of performing a heat treatment at a second temperature at a position separated from the heat treatment plate in the heat treatment apparatus by a certain distance;
Next, a second heating step of placing the substrate on the heat treatment plate and performing heat treatment at a third temperature,
In the preparation step, the temperature of the substrate is set to the same temperature as the second temperature or lower than the second temperature by placing the substrate carried into the heat treatment apparatus on a heat treatment plate. The heat treatment method is characterized in that the heat treatment method is performed in a time shorter than the treatment time in the first heating step and the second heating step.   The preparation step is characterized in that the temperature of the substrate is raised to the first temperature at a heating rate faster than the heating rate of the substrate when the first heating step is performed after the substrate carrying-in step. The heat treatment method according to claim 1. A storage medium storing a computer program used in a heat treatment apparatus for heat-treating a substrate on which a coating film is formed,
A storage medium in which a step group is incorporated in the computer program so as to execute the heat treatment method according to claim 1 or 2 . A heat treatment plate disposed in the heat treatment apparatus and carrying the heat treatment by placing the substrate;
A support mechanism capable of moving up and down to support the substrate carried into the heat treatment apparatus at a raised position spaced apart from the heat treatment plate by a certain distance, and to place the substrate on the heat treatment plate at a lowered position;
A controller that controls the temperature of the heat treatment plate and the raising and lowering of the support mechanism,
The controller is
The temperature of the substrate carried into the heat treatment apparatus is raised to a first temperature (preparation step), and then at a second temperature at a position where the substrate is separated from the heat treatment plate in the heat treatment apparatus by a certain distance. Next, the substrate is placed on the heat treatment plate and heated at a third temperature (second heating step), and the preparation step is performed on the heat treatment apparatus. The temperature of the substrate is raised to the same temperature as the second temperature or a first temperature lower than the second temperature by placing the loaded substrate on a heat treatment plate, A heat treatment apparatus, wherein the heat treatment plate and the support mechanism are controlled so as to be performed in a time shorter than the treatment time in the first heating step and the second heating step.

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