JP2006339555A - Method, apparatus and system for heat-treating substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method, apparatus and system for heat-treating a substrate in which individual differences among apparatuses for heat-treating a substrate can be easily canceled. <P>SOLUTION: In this apparatus for heat-treating a substrate, the individual differences are canceled. In a heating unit HP1, a substrate W is heat-treated while being placed on a placing plate 11. The placing plate 11 comprises a heat pipe structure and by applying an electric current to a heater 15 which is a heat-generating resistor to evaporate a hydraulic fluid 16, a substrate W placed on a placing surface 11a is heated. In an apparatus comprising a plurality of such heating units HP1 for causing these heating units HP1 to perform the same heat-treatment, by attaching a screw for a balancer which is made of the same material as that of a female screw 29 to the female screw 29 to make weights of different placing plates 11 in different apparatuses even and consequently to make calorific capacities of the different placing plates 11 equal, individual differences among different apparatuses can be canceled. Alternatively, by attaching a variable resistance to the heater 15, different plate resistance values of different placing plates 11 may be made even. Further alternatively, values of the electric power output to the heater 15 may be amended based on the weights and resistance values of different placing plates 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a substrate heat treatment apparatus for performing a heat treatment by placing a semiconductor substrate, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, a substrate for an optical disk (hereinafter simply referred to as “substrate”) on a plate, The present invention relates to a substrate heat treatment method using a substrate heat treatment apparatus, and a substrate heat treatment system including a plurality of substrate heat treatment apparatuses.

  In the manufacturing process of a semiconductor device or a liquid crystal display, a number of heat treatments are performed on the substrate. For example, heat treatment is performed in a vapor atmosphere of HMDS (hexamethyldisilazane) when performing a substrate adhesion strengthening process, and heat treatment is also performed when a resist film is formed after applying a photoresist to the substrate. In particular, the post-exposure heat treatment performed when a chemically amplified resist is used is an important step that greatly affects device characteristics. A substrate heat treatment apparatus that heats a substrate by placing the substrate on a plate incorporating a heating resistor is often used as a unit for performing such heat treatment.

  In a heat treatment unit using such a heating resistor as a heat source, the temperature of the plate is generally controlled by PID control (Proportional-Integral-Derivative). As is well known, PID control is an aspect of feedback control, and controls output to a heating resistor based on a detection signal from a temperature sensor provided on a plate. The control mode at this time varies depending on the set PID constant. Patent Document 1 discloses a technique for changing the PID constant according to the processing content, for example, changing the PID constant when changing the plate temperature and when performing heat treatment of the substrate on the plate.

JP 2000-294473 A

  By the way, with the recent progress of higher precision design rules, the temperature accuracy requirement for the heat treatment of the substrate has become increasingly severe. In particular, with regard to the post-exposure heat treatment in the case of using the above-described chemically amplified resist, an extremely strict accuracy that an allowable error with respect to a set temperature is within 0.05 ° C. has been required.

  In addition to the requirement for temperature accuracy, it is also desired to shorten the time until the plate temperature returns to a predetermined processing temperature after the substrate is loaded. This is because promptly returning the plate temperature to a predetermined processing temperature leads to a reduction in the difference between the heat treatment units for the heat treatment of the substrate.

  On the other hand, even heat treatment units manufactured according to the same standard / specification have unavoidable manufacturing errors (so-called “tolerance” or “machine difference”) between the units. In such a situation where there is a difference between heat treatment units, in order to satisfy the above-described requirement for temperature accuracy and the requirement for shortening the time to return to the treatment temperature, it is possible to optimize and set the PID constant for each unit. Necessary. In other words, even if the PID constant is optimal for a certain heat treatment unit, it may not be optimal for other heat treatment units due to machine differences. The PID constant optimized for one heat treatment unit may be used as it is for another unit. In such a method, the temperature accuracy satisfying the above required level and the return time to the processing temperature may not always be obtained for these other units.

  However, the work of optimizing the PID constant is complicated, and the optimization work of the PID constant has not been carried out for every one of the many heat treatment units mounted on the apparatus for performing the resist coating process and the development process. There was a problem that it took an enormous amount of time.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a substrate heat treatment method, a substrate heat treatment apparatus, and a substrate heat treatment system that can easily eliminate the machine differences existing between the substrate heat treatment apparatuses. To do.

  In order to solve the above-mentioned problem, the invention of claim 1 is a substrate heat treatment method in which a plurality of substrate heat treatment apparatuses for performing a heat treatment by placing a substrate on a plate and performing the heat treatment, the plurality of substrates A step of adjusting the weight of the plate to the maximum weight by attaching a weight adjusting member to each plate other than the plate having the maximum weight among the plates provided in the heat treatment apparatus.

  Further, the invention of claim 2 is a substrate heat treatment method in which a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat-treat the substrate by a heating resistor incorporated in the plate perform the same heat treatment. The resistance value of the variable resistor attached to each of the plates other than the plate having the maximum resistance value of the heating resistor among the plates provided in the plurality of substrate heat treatment apparatuses is changed. Adjusting the resistance value to the maximum value.

  Further, the invention of claim 3 is a substrate heat treatment method in which a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat-treat the substrate with a heating resistor incorporated in the plate perform the same heat treatment. An average weight calculating step for calculating an average weight of the plates provided in the plurality of substrate heat treatment apparatuses, and an average resistance value calculation for calculating an average resistance value of the heating resistors provided in the plurality of substrate heat treatment apparatuses. A temperature measuring step of measuring the plate temperature of each of the plurality of substrate heat treatment apparatuses, and a measurement temperature obtained in the temperature measurement process and a plate setting temperature for each of the plurality of substrate heat treatment apparatuses And calculating a standard output value to the plate, and for each of the plurality of substrate heat treatment apparatuses, the plate of the substrate heat treatment apparatus with respect to the average weight. And a correction step of calculating the final output value to the plate resistor ratio of the resistance value of the heating resistor by multiplying the standard output value of the substrate heat treatment apparatus to weight ratio and the average resistance value of the weight.

  According to a fourth aspect of the present invention, there is provided a substrate heat treatment apparatus for performing a heat treatment by placing a substrate on a plate, and further comprising a mounting portion to which a weight adjusting member can be attached and detached.

  The invention of claim 5 is a substrate heat treatment apparatus for placing a substrate on a plate and heat-treating the substrate with a heating resistor incorporated in the plate, wherein a variable resistor is attached to the heating resistor. Yes.

  Further, the invention of claim 6 is a substrate heat treatment apparatus for placing a substrate on a plate and performing heat treatment of the substrate by a heating resistor incorporated in the plate, wherein the temperature measuring means measures the temperature of the plate. Calculating means for calculating a standard output value to the plate based on the measured temperature obtained by the temperature measuring means and the plate set temperature, a weight ratio of the plate weight of the plate to a predetermined standard weight, and a predetermined Correction means for calculating a final output value to the plate by multiplying the standard output value by a resistance ratio of the resistance value of the heating resistor to a standard resistance value.

  The invention of claim 7 is a substrate heat treatment system comprising a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat treat the substrate with a heating resistor incorporated in the plate, Average weight calculation means for calculating the average weight of the plates provided in the substrate heat treatment apparatus, and average resistance value calculation means for calculating the average resistance value of the heating resistors provided in the plurality of substrate heat treatment apparatuses. , A temperature measuring means for measuring the plate temperature of the substrate heat treatment apparatus for each of the plurality of substrate heat treatment apparatuses, and a standard output value to the plate based on the measured temperature and the plate set temperature obtained by the temperature measurement means Calculating means for calculating the resistance of the heating resistor of the substrate heat treatment apparatus with respect to the weight ratio of the plate weight of the plate to the average weight and the average resistance value It comprises a correcting means for calculating a final output value to the plate by multiplying the resistance ratio of the values in the standard output value.

  According to the first aspect of the present invention, the weight adjusting member is attached to each of the plates other than the plate having the maximum weight among the plates provided in the plurality of substrate heat treatment apparatuses, and the weight of the plate is adjusted to the maximum weight. Therefore, the plate weights of the respective substrate processing apparatuses can be made uniform to make the heat capacity uniform, and the machine difference existing between the substrate heat treatment apparatuses can be easily eliminated.

  According to the invention of claim 2, the resistance value of the variable resistor attached to each of the plates other than the plate having the maximum resistance value of the heating resistor among the plates provided in the plurality of substrate heat treatment apparatuses is obtained. Since the resistance value of the plate is adjusted to the maximum value by changing, the plate resistance value of each substrate processing apparatus can be made uniform so that the heat generation amount can be made uniform. Can be solved easily.

  According to the invention of claim 3, for each of the plurality of substrate heat treatment apparatuses, the weight ratio of the plate weight of the substrate heat treatment apparatus to the average weight and the resistance value of the heating resistor of the substrate heat treatment apparatus with respect to the average resistance value Since the final output value to the plate is calculated by multiplying the resistance ratio by the standard output value, the output value can be corrected considering the weight and resistance value of the plate. Can be solved easily.

  According to a fourth aspect of the present invention, there is provided a substrate heat treatment apparatus for performing a heat treatment by placing a substrate on a plate, and the plate is provided with an attachment portion to which a weight adjusting member can be attached and detached. The machine difference existing between the substrate heat treatment apparatuses can be easily eliminated simply by attaching the adjusting member.

  According to the invention of claim 5, since the variable resistor is attached to the heating resistor, the machine difference existing between the substrate heat treatment apparatuses can be easily eliminated by simply changing the resistance value of the variable resistor. .

  According to the sixth aspect of the present invention, the standard output value is multiplied by the weight ratio of the plate weight to the predetermined standard weight and the resistance ratio of the resistance value of the heating resistor to the predetermined standard resistance value. Since the final output value is calculated, the output value can be corrected in consideration of the weight and resistance value of the plate, and the machine difference existing between the substrate heat treatment apparatuses can be easily eliminated.

  According to the invention of claim 7, the final output value to the plate is obtained by multiplying the standard output value by the weight ratio of the plate weight of the plate to the average weight and the resistance ratio of the resistance value of the heating resistor to the average resistance value. Since the calculation is performed, the output value can be corrected in consideration of the weight and resistance value of the plate, and the machine difference existing between the substrate heat treatment apparatuses can be easily eliminated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<1. Configuration of substrate processing apparatus>
1 and 2 are views showing an example of a substrate processing apparatus incorporating a substrate heat treatment apparatus according to the present invention. FIG. 1 is a plan view of the substrate processing apparatus 1. The substrate processing apparatus 1 is an apparatus that performs a resist coating process and a development process on a substrate W. The substrate processing apparatus 1 includes an indexer ID that carries a substrate W in and out of the apparatus and a plurality of processing units that process the substrate W. An interface IF for transferring the substrate W between the first processing unit group PG1 and the second processing unit group PG2, and an exposure apparatus (stepper) (not shown), and a transport robot TR.

  The indexer ID mounts a carrier (not shown) that can store a plurality of substrates W and includes a mobile robot. The indexer ID pays out an unprocessed substrate from the carrier to the transport robot TR and removes a processed substrate from the transport robot TR. Receive and store in carrier. In addition to the FOUP (front opening unified pod) that accommodates the substrate W in a sealed space, the carrier may be a standard mechanical interface (SMIF) pod or an OC (open cassette) that exposes the storage substrate W to the outside air. May be.

  The interface IF has a function of receiving the resist-coated substrate W from the transport robot TR and passing it to an exposure apparatus (not shown), and receiving the exposed substrate W and passing it to the transport robot TR. Further, the interface IF has a buffer function for temporarily stocking the substrate before and after the exposure in order to adjust the delivery timing with the exposure apparatus. Although not shown, the interface IF is connected to the transfer robot TR. A robot for delivering W and a buffer cassette on which a substrate is placed are provided.

  The substrate processing apparatus 1 includes a plurality of processing units (processing units) for processing the substrate W, part of which constitutes the first processing unit group PG1, and the remaining part of the second processing unit group PG2. Configure. FIG. 2 is a diagram illustrating configurations of the first processing unit group PG1 and the second processing unit group PG2. The first processing unit group PG1 is configured by arranging a plurality of heat treatment units above the coating processing units SC1 and SC2 which are liquid processing units. In FIG. 2, the processing units are two-dimensionally arranged for convenience of illustration, but are actually stacked in the height direction (Z-axis direction in FIG. 1).

  The coating processing units SC1 and SC2 are so-called spin coaters that perform uniform resist coating processing by supplying a photoresist to the main surface of the substrate and rotating the substrate W. Three rows of heat treatment units stacked in three stages are provided above the coating processing units SC1 and SC2. That is, the cooling unit CP1, the adhesion strengthening unit AH, the heating unit HP1 are stacked in order from the bottom, the cooling unit CP2, the heating unit HP2, and the heating unit HP3 are stacked, the cooling unit CP3, the heating unit HP4, A row in which the heating units HP5 are stacked is provided.

  Similarly, the second processing unit group PG2 is configured by arranging a plurality of heat treatment units above the development processing units SD1 and SD2 which are liquid processing units. The development processing units SD1 and SD2 are so-called spin developers that perform development processing by supplying a developing solution onto the exposed substrate. Three rows of heat treatment units stacked in three stages are provided above the development processing units SD1 and SD2. That is, the cooling unit CP4, the post-exposure bake unit PEB, and the heating unit HP6 are stacked in order from the bottom, the cooling unit CP5, the heating unit HP7, and the heating unit HP8 are stacked, the cooling unit CP6, and the heating unit HP9. And a row in which the heating units HP10 are stacked.

  The heating units HP1 to HP10 are so-called hot plates that heat the substrate W and raise the temperature to a predetermined temperature. The adhesion strengthening unit AH and the post-exposure bake unit PEB are also heating units that heat the substrate W before and after the resist coating process, respectively. The cooling units CP1 to CP6 are so-called cool plates that cool the substrate W to a predetermined temperature and maintain the substrate W at the predetermined temperature.

  In the present specification, units (heating unit and cooling unit) for adjusting the temperature of the substrate W are referred to as heat treatment units. A processing unit that supplies a processing liquid to a substrate such as the coating processing units SC1 and SC2 and the development processing units SD1 and SD2 and performs a predetermined processing is referred to as a liquid processing unit. The liquid processing unit and the heat treatment unit are collectively referred to as a processing unit.

  A filter fan unit FFU that forms a downflow of clean air whose temperature and humidity are controlled is provided immediately above the liquid processing unit. Although not shown, a filter fan unit that forms a downflow of clean air toward the transfer space is also provided at an upper position where the transfer robot TR is disposed.

  The transport robot TR includes two holding arms (not shown), and can raise and lower the holding arms and turn the holding arms in a horizontal plane. Further, the transport robot TR is configured to be able to move the two holding arms forward and backward in the turning radius direction independently of each other. As a result, the transfer robot TR allows the two holding arms to individually access the processing units provided in the first processing unit group PG1 and the second processing unit group PG2, and the substrate W between them. Can give and receive. In addition, the transfer robot TR exchanges the substrate W with the indexer ID and the interface IF via a predetermined delivery unit.

  When processing the substrate W in the substrate processing apparatus 1 having the above-described configuration, the transfer robot TR receives the unprocessed substrate W paid out from the indexer ID, and is provided in the first processing unit group PG1 according to a predetermined processing procedure. The resist coating process is performed by sequentially transporting to the processed units. The substrate W on which the resist film is formed is transferred to the interface IF by the transfer robot TR and then transferred into the exposure apparatus. The exposed substrate W is again transferred to the transport robot TR through the interface IF, and the transport robot TR sequentially transports the substrate W to the processing unit provided in the second processing unit group PG2 according to a predetermined processing procedure, so that the development process is performed. Is called. The substrate W for which the development processing has been completed is transferred to the indexer ID by the transport robot TR and stored in a predetermined carrier. In general, a series of coating and developing processes are executed as described above.

  In the present specification, among the plurality of heating units provided in the substrate processing apparatus 1, the heating units HP1 to HP5 of the first processing unit group PG1 and the heating units HP6 to HP10 of the second processing unit group PG2 are mutually connected. Treated as a heat treatment unit that performs the same heat treatment. The heat treatment having the same content means a heat treatment performed at the same set temperature for the same time.

<2. Heat treatment unit configuration>
Next, the description of the configuration of the heating unit HP1 will be further continued. Here, although heating unit HP1 is demonstrated, it has the same structure also about heating unit HP2-HP10.

  FIG. 3 is a side sectional view showing a schematic configuration of a heating unit HP1 as a substrate heat treatment apparatus according to the present invention, and FIG. 4 is a plan view of a mounting plate of the heating unit HP1.

  The mounting plate 11 corresponding to the plate according to the present invention adopts a heat pipe structure to increase the in-plane uniformity of the temperature distribution while extremely reducing the heat capacity, and is a metal having a good thermal conductivity, for example, It is made of copper. The substrate W is placed on the placement surface 11 a that is in contact with the upper surface of the placement plate 11. A plurality of ceramic balls (proximity balls) (not shown) are dispersed and fitted on the mounting surface 11a, and the substrate W is supported in a point contact state from the back surface to prevent uneven heat treatment. However, the small sphere may be omitted and the substrate W may be supported in a surface contact state.

  A cavity is formed inside the flat portion 13 located at the top of the mounting plate 11. The internal space 12 is decompressed due to the heat pipe structure, and a plurality of pillars 13b are erected so as to supplement the strength in the vertical direction.

  Two hydraulic fluid chambers 14 are provided at a lower position of the mounting plate 11. Each hydraulic fluid chamber 14 has a substantially rectangular parallelepiped shape, and is configured such that the two hydraulic fluid chambers 14 sandwich the center of the mounting plate 11 in plan view. These hydraulic fluid chambers 14 incorporate a heater 15 as a heating resistor and store hydraulic fluid 16. In the present embodiment, for example, water is used as the hydraulic fluid 16.

  A plurality of concave holes are formed in the bottom of the mounting plate 11 (that is, the bottom of the hydraulic fluid chamber 14), and a female screw 29 is engraved on the inner wall surface of each hole. Each female screw 29 functions as an attachment part to which a balancer screw as a weight adjusting member can be detachably attached. The forming position of the female screw 29 is not limited to the bottom portion of the mounting plate 11 and may be a side surface.

  Further, the hydraulic fluid chamber 14 and the internal space 12 of the flat portion 13 communicate with each other, thereby realizing a heat pipe structure in the mounting plate 11. In other words, the vapor of the working fluid 16 generated by heating the heater 15 moves in the working space with the internal space 12 as the working area, and transfers and transfers the latent heat of vaporization to make the temperature distribution on the mounting surface 11a uniform. The holding surface 11a can be rapidly heated while being held.

  As shown in FIG. 4, the cooling pipe 21 serving as a cooling structure in the heating unit HP <b> 1 is disposed in almost the entire area of the internal space 12 of the mounting plate 11. The cooling pipe 21 is made of a heat conductive material (for example, metal or alloy), and is disposed so as to be substantially horizontal and face almost the entire surface of the mounting surface 11a.

  The cooling pipe 21 is connected to a cooling medium supply source 25 via a supply pipe 22. An on-off valve 26 is inserted in the middle of the supply pipe 22. The cooling pipe 21 is also connected to a drain (not shown) through a discharge pipe 23. Therefore, the cooling medium supplied from the cooling medium supply source 25 is supplied to the cooling pipe 21 via the supply pipe 22 by opening the on-off valve 26, and the internal space 12 of the mounting plate 11 via the cooling pipe 21. After the heat exchange, the exhaust pipe 23 is discharged to a drain (not shown). That is, the surface of the cooling pipe 21 is in contact with the working fluid in the internal space 12, and a cooling action to the mounting surface 11a is generated via this working fluid. In other words, the working fluid having the heat pipe structure can be heated by the heater 15 or can be cooled by the cooling pipe 21.

  As shown in FIG. 4, the cooling pipe 21 is arranged in a meandering manner so that the internal space 12 of the mounting plate 11 is folded back multiple times in order to increase the surface area thereof. Therefore, heat exchange between the cooling pipe 21 and the internal space 12 can be performed efficiently.

  Further, the cooling pipe 21 is supported on the wall surface of the flat portion 13 of the mounting plate 11 via the mounting plate 11 and a ring-shaped (donut-shaped) heat insulating member 24. Therefore, since the cooling pipe 21 and the mounting plate 11 are thermally blocked by the heat insulating member 24, the heat transfer from the cooling pipe 21 to the mounting plate 11 does not occur. Examples of the heat insulating member 24 include ceramics and heat resistant resin.

  The temperature sensor 27 is embedded in the mounting plate 11 so that the temperature of the mounting surface 11a can be measured. The temperature of the substrate W placed on the placement surface 11 a is calculated based on the temperature measured by the temperature sensor 27.

  FIG. 5 is a block diagram showing an outline of the control mechanism of the heating unit HP1. The baking unit 30 is provided in the heating unit HP1. The configuration of the bake controller 30 as hardware is the same as that of a general computer. That is, the bake controller 30 stores a CPU 31 that performs various arithmetic processes, a ROM 32 that is a read-only memory that stores basic programs, a RAM 33 that is a readable / writable memory that stores various data, and control applications and data. A magnetic disk 34 or the like is provided. The bake controller 30 is electrically connected to the temperature sensor 27 and the on-off valve 26 described above via an interface (not shown), and controls these operations. The bake controller 30 is also connected to a power unit 35 for supplying power to the heater 15 described above.

  FIG. 6 shows a circuit composed of the power unit 35 and the heater 15. As shown in the figure, two heaters 15 built in the mounting plate 11 are connected in parallel to a power unit 35 as a power supply source. A variable resistor 39 is attached to the heater 15. The variable resistor 39 is a resistor that can change the resistance value.

  Returning to FIG. 5, the bake controller 30 is also connected to a main controller MC that manages the entire substrate processing apparatus 1. The configuration of the main controller MC as hardware is the same as that of a general computer. The main panel MP functions as a display for the main controller MC. In addition, various commands and parameters can be input to the main controller MC from the keyboard KB. The main panel MP may be configured by a touch panel, and input work may be performed from the main panel MP to the main controller MC.

  The bake controller 30 functions as a lower control unit of the main controller MC, and in particular is a control unit for controlling the heating unit HP1 exclusively. The heating units HP2 to HP10 are also provided with similar dedicated bake controllers, which all serve as the lower-level control units of the main controller MC.

<3. Operation of heat treatment unit>
Next, the operation of the heating unit HP1 having the above-described configuration will be briefly described. For each of the heating units HP1 to HP10, a set temperature according to the processing content of the substrate W is determined. In the present embodiment, since the heating units HP1 to HP5 are heat treatment units that perform heat treatment of the same content, the same set temperature is set for them. This set temperature is transmitted from the main controller MC to the baking controller 30 of each heating unit. Then, the bake controller 30 controls the power unit 35 to start energization of the heater 15, evaporate the working fluid 16 and heat the mounting surface 11a. At this time, based on the temperature measurement result of the temperature sensor 27, the bake controller 30 performs PID control of the power unit 35 so that the mounting surface 11a becomes the set temperature. In the heating unit HP1, since the placement plate 11 has a heat pipe structure, the temperature of the placement surface 11a quickly rises to the heating temperature.

  The bake controller 30 that has confirmed that the mounting surface 11a has been heated to a predetermined set temperature transmits a signal to that effect to the main controller MC. Thereby, the transport robot TR carries the substrate W into the heating unit HP1 and places it on the placement surface 11a. From this point, the heat treatment for the substrate W is started.

  After the heat treatment for a predetermined time is completed, the transfer robot TR unloads the substrate W from the heating unit HP1. Thereafter, when the bake controller 30 receives an instruction to lower the set temperature from the main controller MC, the bake controller 30 controls the power unit 35 and ends energization of the heater 15. And the bake controller 30 opens the on-off valve 26, supplies a cooling medium to the cooling pipe 21, and lowers the temperature of the mounting surface 11a.

<4. Method for eliminating machine differences between heating units>
As described above, in the present embodiment, the heating units HP1 to HP5 each perform the same heat treatment. Although the heating units HP1 to HP5 are heat treatment units manufactured according to the same standard and specification, as described above, inevitable machine differences (tolerances) exist between such units. In the present embodiment, in order to satisfy strict accuracy requirements for substrate processing, machine differences between the heating units HP1 to HP5 are eliminated as follows.

<4-1. Adjustment of plate weight>
The weight of the mounting plate 11 is linear with the plate heat capacity, which is a temperature time constant. That is, if the weight of the mounting plate 11 is different, the degree of temperature rise is different even if the same amount of heat is applied. Therefore, one of the machine difference elimination methods is to align the plate weights of the heating units HP1 to HP5.

  Specifically, the weights of the mounting plates 11 other than the mounting plate 11 having the maximum weight among the mounting plates 11 provided in the heating units HP1 to HP5 are adjusted to the maximum weight. For example, when the weight of the mounting plate 11 of the heating unit HP2 is the largest, the weight of the mounting plate 11 of the heating units HP1, HP3 to HP5 is adjusted to be equal to the weight of the mounting plate 11 of the heating unit HP2. To do. As shown in FIG. 7, the weight adjustment method is performed by using a balancer screw 28 made of the same material as that of the mounting plate 11 (copper in this embodiment) as a female screw 29 of the mounting plate 11 of the heating units HP1, HP3 to HP5. Install. As the balancer screw 28, a plurality of types having various weights are prepared in advance. Then, a balancer screw 28 having an optimal weight is attached to the female screw 29 of the mounting plate 11 according to the difference between the weight of the mounting plate 11 to be weight adjusted and the maximum weight. The weight of the mounting plate 11 may be adjusted by combining a plurality of balancer screws 28.

  If it does in this way, the weight of the mounting plate 11 with which heating unit HP1-HP5 was equipped will become uniform mutually by the simple method of only attaching a screw, the heat capacity of each mounting plate 11 will become equal, and a machine difference will be carried out. Is resolved. Note that the method of adjusting the weight is not limited to screw attachment, and any method may be used as long as a member made of the same material as the mounting plate 11 is added.

<4-2. Adjustment of plate resistance>
The mounting plate 11 is provided with a heater 15 as a heating resistor. The reciprocal of the resistance value of the heater 15 is linear with the amount of heat generated when a constant voltage is applied to the heater 15. That is, the greater the resistance value of the heater 15, the less heat is generated when a constant voltage is applied. Therefore, another one of the machine difference elimination methods is to align the plate resistance values of the heating units HP1 to HP5.

  Specifically, among the mounting plates 11 provided in the heating units HP <b> 1 to HP <b> 5, the variable resistors 39 provided on the mounting plates 11 other than the mounting plate 11 having the maximum resistance value of the heater 15. The resistance value of the mounting plate 11 is adjusted to the maximum value by changing the resistance value. For example, when the resistance value of the mounting plate 11 of the heating unit HP3 is the maximum, the resistance value of the variable resistor 39 attached to each of the heating units HP1, HP2, HP4, and HP5 is changed to change them. The resistance value of the mounting plate 11 is adjusted to be equal to the plate resistance value of the heating unit HP3.

  In this way, the plate resistance values of the mounting plates 11 provided in the heating units HP1 to HP5 are made uniform with each other by a simple method in which only the resistance value of the variable resistor 39 is changed. The machine difference between is eliminated. The method of adjusting the plate resistance value is not limited to the attachment of the variable resistor 39, but a resistance corresponding to the difference between the maximum resistance value and the plate resistance value of each mounting plate 11 is attached. Also good. However, adjustment is easier when the variable resistor 39 is used.

<4-3. Adjustment of output value to plate>
As is apparent from the above description, the main parameters of the mounting plate 11 that affect the uniformity of the heat treatment are the weight and resistance value of the plate. The parameter “1 / (weight / resistance value)” taking in the weight of the plate and the plate resistance value is referred to as “plate specific value”. The above-described two methods directly adjust the plate eigenvalue, in other words, directly eliminate the machine difference between the heating units HP1 to HP5 generated at the time of manufacture.

  On the other hand, the temperature control of the mounting plate 11 is executed by the PID control of the bake controller 30, and the plate-specific values of the mounting plates 11 of the heating units HP1 to HP5 are input in advance to the corresponding bake controller 30, By correcting the output value to the heater 15 on the basis thereof, the uniformity of the heat treatment unit can be ensured as a result. In other words, the plate eigenvalue is directly used as a predetermined parameter, and the machine difference between the heating units HP1 to HP5 is indirectly eliminated from the control surface (software surface) based on the plate eigenvalue.

  Specifically, first, the average weight “W” of the mounting plate 11 provided in the heating units HP1 to HP5 is calculated. The operator individually inputs the weight of each mounting plate 11 of the heating units HP1 to HP5 from the keyboard KB to the main controller MC. The main controller MC calculates the average weight “W” based on the input data. The calculated average weight “W” data is transferred from the main controller MC to the respective bake controllers 30 of the heating units HP1 to HP5 and stored in the respective magnetic disks 34, for example. The individual weights of the mounting plates 11 of the heating units HP1 to HP5 are also transferred from the main controller MC to the corresponding bake controller 30 and stored in the magnetic disk 34, for example. Note that the operator may calculate the average weight “W” outside the apparatus and input it to the main controller MC from the keyboard KB.

  Next, the average resistance value “R” of the heater 15 provided in the heating units HP1 to HP5 is calculated. Similarly to the above, the worker individually inputs the resistance value of each heater 15 of the heating units HP1 to HP5 from the keyboard KB to the main controller MC. The main controller MC calculates the average resistance value “R” based on the input data. The calculated data of the average resistance value “R” is transferred from the main controller MC to each bake controller 30 of the heating units HP1 to HP5 and stored in each magnetic disk 34, for example. Further, the individual resistance values of the heaters 15 of the heating units HP1 to HP5 are also transferred from the main controller MC to the corresponding bake controller 30 and stored in the magnetic disk 34, for example. The operator may calculate the average resistance value “R” outside the apparatus and input it to the main controller MC from the keyboard KB.

  The PID control of the power unit 35 is executed in a state where the bake controller 30 of the heating units HP1 to HP5 holds the average weight “W” and the average resistance value “R”. FIG. 8 is a block diagram showing a process of calculating a final output value from the power unit 35 to the heater 15.

  Here, first, the bake controller 30 calculates a standard output value to the heater 15 in accordance with a normal PID control method. The standard output value is an output value calculated based only on the difference between the set temperature and the temperature measured by the temperature sensor 27 without taking into account any plate specific values. That is, as described above, since the heating units HP1 to HP5 are heat treatment units that perform heat treatment with the same content, the same set temperature is set for them. And in each of heating unit HP1-HP5, the temperature sensor 27 is measuring the temperature of the mounting surface 11a sequentially. Each of the bake controllers 30 of the heating units HP1 to HP5 calculates a standard output value to the heater 15 based on a deviation between the set temperature and a temperature measured by the temperature sensor 27 by a normal PID control method.

  In the present embodiment, the bake controller 30 further corrects the standard output value based on the plate eigenvalue. The correction calculation at this time is performed according to the following formula 1. In Equation 1, “Wi” and “Ri” are the individual weights of the mounting plates 11 and the individual resistance values of the heaters 15 of the heating units HP1 to HP5.

  That is, in each of the heating units HP1 to HP5, the bake controller 30 performs the weight ratio of the plate weight “Wi” of the mounting plate 11 to the average weight “W” and the resistance value “Ri” of the heater 15 with respect to the average resistance value “R”. The final output value to the mounting plate 11 is calculated by multiplying the standard output value by using the resistance ratio as a correction coefficient.

  In this way, just by inputting the weight value of the mounting plate 11 and the resistance value of the heater 15, the output value correction considering the plate-specific value of the mounting plate 11, which is the main factor affecting the uniformity of the heat treatment. And the machine difference between the mounting plates 11 can be easily eliminated.

  Here, the average weight “W” and the average resistance value “R” of the mounting plates 11 of the heating units HP1 to HP5 are calculated, and the output value to each mounting plate 11 is corrected based on the calculated weights. However, the weight and resistance value of the mounting plate 11 with optimized PID constants are set as the standard weight and the standard resistance value, respectively, and the weight of the plate weight of the mounting plate 11 with respect to the standard weight. The final output value to the mounting plate 11 may be calculated by multiplying the standard output value by using the resistance ratio of the resistance value of the heater 15 to the ratio and the standard resistance value as a correction coefficient.

<5. Modification>
While the embodiments of the present invention have been described above, the present invention is not limited to the above examples. For example, the heating unit is not limited to a heat treatment unit adopting a heat pipe structure, but may be a heat treatment unit of a type in which a heating resistor is embedded in a metal (for example, aluminum) flat plate.

  Further, the above three machine difference elimination methods may be implemented alone, or a plurality of them may be implemented in combination as appropriate.

  The substrate heat treatment technology according to the present invention is not limited to the heating units HP1 to HP5, and may be any heat treatment unit that performs heat treatment with the same contents, for example, the heating unit HP6. -Heating unit HP10 may be sufficient. In particular, it is preferable to provide a plurality of post-exposure bake units PEB that require strict temperature accuracy and apply the technique according to the present invention to them.

It is a top view of the substrate processing apparatus incorporating the substrate heat processing apparatus which concerns on this invention. It is a figure which shows the structure of the 1st process part group of the substrate processing apparatus of FIG. 1, and a 2nd process part group. It is a sectional side view which shows schematic structure of the substrate heat processing apparatus which concerns on this invention. It is a top view of the mounting plate of the substrate heat processing apparatus of FIG. It is a block diagram which shows the outline of the control mechanism of the substrate heat processing apparatus of FIG. It is a figure which shows the circuit comprised with a power unit and a heater. It is a figure which shows a mode that the screw for balancers is attached to a female screw, and weight adjustment is performed. It is a block diagram which shows the process of calculating the final output value from a power unit to a heater.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 11 Mounting plate 15 Heater 27 Temperature sensor 28 Screw for balancer 29 Female screw 30 Bake controller 35 Power unit 39 Variable resistance HP1-HP10 Heating unit MC Main controller W Substrate

Claims (7)

A substrate heat treatment method in which a plurality of substrate heat treatment apparatuses for performing heat treatment by placing a substrate on a plate and performing heat treatment,
A substrate comprising a step of adjusting a weight of the plate to the maximum weight by attaching a weight adjusting member to each of the plates other than the plate having the maximum weight among the plates provided in the plurality of substrate heat treatment apparatuses. Heat treatment method. A substrate heat treatment method in which a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat-treat the substrate with a heating resistor incorporated in the plate perform the same heat treatment,
By changing the resistance value of the variable resistor attached to each of the plates other than the plate having the maximum resistance value of the heating resistor among the plates provided in the plurality of substrate heat treatment apparatuses, the resistance value of the plate is set. A substrate heat treatment method comprising the step of adjusting to the maximum value. A substrate heat treatment method in which a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat-treat the substrate with a heating resistor incorporated in the plate perform the same heat treatment,
An average weight calculating step for calculating an average weight of the plates provided in the plurality of substrate heat treatment apparatuses;
An average resistance value calculating step for calculating an average resistance value of the heating resistors provided in the plurality of substrate heat treatment apparatuses;
A temperature measuring step of measuring each plate temperature of the plurality of substrate heat treatment apparatuses;
For each of the plurality of substrate heat treatment apparatuses, a calculation step for calculating a standard output value to the plate based on the measurement temperature and the plate set temperature obtained in the temperature measurement step,
For each of the plurality of substrate heat treatment apparatuses, the weight ratio of the plate weight of the substrate heat treatment apparatus to the average weight and the resistance ratio of the resistance value of the heating resistor of the substrate heat treatment apparatus to the average resistance value are set to the standard output value. A correction process to calculate the final output value to the plate by multiplying,
A substrate heat treatment method comprising: A substrate heat treatment apparatus for performing a heat treatment by placing a substrate on a plate,
An apparatus for heat treating a substrate, comprising: a mounting portion for attaching / detaching a weight adjusting member to / from the plate. A substrate heat treatment apparatus that places a substrate on a plate and heat-treats the substrate with a heating resistor incorporated in the plate,
A substrate heat treatment apparatus, wherein a variable resistor is attached to the heating resistor. A substrate heat treatment apparatus that places a substrate on a plate and heat-treats the substrate with a heating resistor incorporated in the plate,
A temperature measuring means for measuring the temperature of the plate;
A calculating means for calculating a standard output value to the plate based on the measured temperature and the plate set temperature obtained by the temperature measuring means;
Correction for calculating a final output value to the plate by multiplying the standard output value by a weight ratio of the plate weight of the plate to a predetermined standard weight and a resistance ratio of the resistance value of the heating resistor to a predetermined standard resistance value Means,
A substrate heat treatment apparatus comprising: A substrate heat treatment system comprising a plurality of substrate heat treatment apparatuses that place a substrate on a plate and heat treat the substrate with a heating resistor incorporated in the plate,
Average weight calculating means for calculating an average weight of the plates provided in the plurality of substrate heat treatment apparatuses;
Average resistance value calculating means for calculating an average resistance value of the heating resistors provided in the plurality of substrate heat treatment apparatuses;
With
Each of the plurality of substrate heat treatment apparatuses includes:
Temperature measuring means for measuring the plate temperature of the substrate heat treatment apparatus;
A calculating means for calculating a standard output value to the plate based on the measured temperature and the plate set temperature obtained by the temperature measuring means;
The final output value to the plate is calculated by multiplying the standard output value by the weight ratio of the plate weight of the plate to the average weight and the resistance ratio of the resistance value of the heating resistor of the substrate heat treatment apparatus to the average resistance value. Correction means;
A substrate heat treatment system comprising:

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