JP3786326B2 - Temperature control apparatus and temperature control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a temperature control apparatus and a temperature control method for controlling the temperature of an object to be controlled such as a wafer, and more specifically, to control the object to be controlled by a temperature fluid selectively supplied by a plurality of fluid circulation supply systems. The present invention relates to an improvement of a temperature control apparatus and a temperature control method for controlling to a plurality of target temperatures.
[0002]
[Prior art]
In the semiconductor manufacturing process, a prebaking process in which the wafer is heated to 110 to 130 ° C. in order to remove the solvent remaining in the applied resist film, or a wafer 120 in order to facilitate the adhesion between the resist and the substrate before etching. Each of these steps includes a heating step such as a post-bake step for heating to ˜150 ° C. and a cooling step such as a cooling step for cooling the heated wafer to a room temperature level (about 20 ° C.) each time. In this case, it is important to improve the throughput to control the temperature of the wafer more efficiently and with high accuracy.
[0003]
An example of this type of prior art is disclosed in Japanese Patent Publication No. 7-11948. In this prior art, a fluid path is provided in a heat plate on which a semiconductor wafer is placed in close contact, and a system for circulating and supplying a heating fluid to the fluid path and a system for circulating and supplying a cooling fluid are prepared. And a supply valve and a discharge valve for selecting the fluid circulation supply system are interposed between the inlet / outlet of the fluid passage and the two fluid circulation supply systems. By switching simultaneously, the temperature fluid to be circulated and supplied to the fluid passage is selected, and the semiconductor wafer is heated or cooled by the selected temperature fluid.
[0004]
According to this prior art, the temperature fluid supplied to the fluid passage of the hot plate can be instantaneously changed by the operation of the supply valve and the discharge valve, and a semiconductor wafer placed in close contact with the hot plate can be quickly desired. It becomes possible to control to the temperature.
[0005]
[Problems to be solved by the invention]
By the way, in this type of temperature control device, since a volume such as a fluid passage exists between the supply valve and the discharge valve, the supply valve and the discharge valve are operated to change the fluid circulation supply system. The temperature fluid before the change by the volume between the supply valve and the discharge valve is mixed in different fluid circulation supply systems.
[0006]
For example, when the supply valve and the discharge valve are respectively switched from the heating fluid circulation supply system to the cooling fluid circulation supply system in order to cool the heated semiconductor wafer, the heating remaining in the pipeline from the supply valve to the discharge valve The fluid is mixed into the cooling fluid circulation supply system, and a large temperature fluctuation is exerted on the cooling fluid circulation supply system.
[0007]
In view of the above circumstances, the present invention provides a temperature control device and a temperature control method capable of quickly controlling an object to be controlled to a plurality of target temperatures without causing a large temperature fluctuation in the fluid circulation supply system. To solve it.
[0008]
[Means for solving the problems and effects]
In the first aspect of the present invention, a plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, the plurality of fluid circulation supply systems, and the object to be temperature controlled. A supply selection means for selecting a supply destination of the temperature fluid to the object to be controlled from among the plurality of fluid circulation supply systems, the plurality of fluid circulation supply systems and the object to be temperature controlled And a return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from among the plurality of fluid circulation supply systems, the supply selection means and the return selection means. In the temperature control apparatus that circulates and supplies a desired temperature fluid to the object to be controlled by controlling the same fluid circulation supply system by the above, the supply selection unit The temperature of the temperature fluid returned from the object to be controlled is detected after changing the fluid circulation supply system, and when the detected temperature reaches the preset change temperature, the return destination of the temperature fluid is the same. In order to change to the fluid circulation supply system, means for operating the return selection means is provided.
[0009]
According to the first aspect of the present invention, after the supply selection means is switched, the return selection means is switched when the temperature of the temperature fluid returned from the object to be controlled reaches the preset change temperature. Therefore, it becomes possible to return the temperature fluid remaining between the supply selection means and the return selection means to the corresponding fluid circulation supply system as much as possible, and fluid circulation supply caused by mixing different temperature fluids Large temperature fluctuations in the system can be prevented.
[0010]
In the invention according to claim 2, a plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, the plurality of fluid circulation supply systems, and the object to be controlled A supply selection means for selecting a supply destination of the temperature fluid to the object to be controlled from among the plurality of fluid circulation supply systems, the plurality of fluid circulation supply systems and the object to be temperature controlled And a return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from among the plurality of fluid circulation supply systems, the supply selection means and the return selection means. In the temperature control apparatus that circulates and supplies a desired temperature fluid to the object to be controlled by controlling the same fluid circulation supply system by the above, the supply selection unit In order to change the return destination of the temperature fluid supplied to the object to be controlled to the same fluid circulation supply system when the elapsed time from the time of changing the fluid circulation supply system reaches a preset time, Means for operating the return selection means is provided.
[0011]
According to the second aspect of the present invention, the return selection means is switched when the preset time elapses after the supply selection means is switched, and therefore remains between the supply selection means and the return selection means. The temperature fluid can be returned to the corresponding fluid circulation supply system as much as possible, and a large temperature fluctuation of the fluid circulation supply system due to mixing of different temperature fluids can be prevented.
[0012]
In the invention according to claim 3, a plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, the plurality of fluid circulation supply systems, and the object to be controlled A supply selection means for selecting a supply destination of the temperature fluid to the object to be controlled from among the plurality of fluid circulation supply systems, the plurality of fluid circulation supply systems and the object to be temperature controlled And a return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from among the plurality of fluid circulation supply systems, the supply selection means and the return selection means. In the temperature control method for controlling the temperature of the object to be controlled by circulating and supplying a desired temperature fluid to the object to be controlled by selecting the same fluid circulation supply system by When the temperature of the temperature fluid returned from the object to be controlled reaches the preset change temperature after changing the fluid circulation supply system by changing the return destination of the temperature fluid to the same fluid circulation supply system Therefore, the return selection means is activated.
[0013]
According to the third aspect of the invention, after the supply selection means is switched, the return selection means is switched when the temperature of the temperature fluid returned from the object to be controlled reaches the preset change temperature. Therefore, it becomes possible to return the temperature fluid remaining between the supply selection means and the return selection means to the corresponding fluid circulation supply system as much as possible, and fluid circulation caused by mixing of different temperature fluids. Large temperature fluctuations in the supply system can be prevented.
[0014]
In the invention according to claim 4, a plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, the plurality of fluid circulation supply systems, and the object to be controlled A supply selection means for selecting a supply destination of the temperature fluid to the object to be controlled from among the plurality of fluid circulation supply systems, the plurality of fluid circulation supply systems and the object to be temperature controlled And a return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from among the plurality of fluid circulation supply systems, the supply selection means and the return selection means. In the temperature control method for controlling the temperature of the object to be controlled by circulating and supplying a desired temperature fluid to the object to be controlled by selecting the same fluid circulation supply system by The return selection means is operated to change the return destination of the temperature fluid supplied to the object to be controlled to the same fluid circulation supply system with a preset time delay from the time when the fluid circulation supply system is changed by I am letting.
[0015]
According to the fourth aspect of the present invention, since the return selection unit is switched with a preset time delay after the supply selection unit is switched, the temperature remaining between the supply selection unit and the return selection unit is changed. It becomes possible to return the fluid to the corresponding fluid circulation supply system as much as possible, and it is possible to prevent a large temperature fluctuation of the fluid circulation supply system due to mixing of different temperature fluids.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings illustrating an embodiment.
FIG. 1 shows a first embodiment of a temperature control device according to the present invention. The temperature control device exemplified here is
(1) Wafer cleaning
(2) Resist coating
(3) Pre-baking (110-130 ° C) + cooling (20 ° C)
(4) Exposure
(5) Development
(6) Rinse
(7) Post baking (120-150 ° C) + Cooling (20 ° C)
(8) Etching
In the semiconductor manufacturing process for forming a resist film through the above process, it is used in the above-described pre-baking + cooling process or post-baking + cooling process. The wafer is heated (baking process), and then the wafer W is cooled to room temperature (cooling process). That is, the temperature control device has two target temperatures of a first target temperature TH during heating and a second target temperature TC during cooling, and performs control to alternately repeat heating and cooling. .
[0017]
As shown in FIG. 1, the temperature control device includes a chamber constituent member 1. The chamber constituent member 1 is formed in a rectangular shape with a material having low thermal conductivity, and has a plurality of (nine not shown in the figure) recesses 2 therein. Each of the recesses 2 has an opening on the top surface, and has a mounting hole 3 in the center of each bottom wall, and each bottom wall top surface is inclined in such a manner that it gradually becomes lower toward the mounting hole 3. While the upper surface is closed by a single base plate 4, each mounting hole 3 is closed by a fluid ejection pipe 5.
[0018]
The base plate 4 is formed in a rectangular flat plate shape with a material having high thermal conductivity such as aluminum or copper, and holds a heat dissipation heat plate 7 via a plurality (nine) of Peltier elements 6 on its upper surface. Yes. As is well known, the Peltier element 6 has a large number of P-type semiconductor pieces and N-type semiconductor pieces arranged alternately on a two-dimensional plane, and the P-type semiconductor pieces and the N-type semiconductor pieces are arranged in a large number of plane electrodes. When a DC current is supplied, the Peltier effect is generated and heat is absorbed on one surface, while heat is dissipated on the other surface. Are joined to portions corresponding to the respective recesses 2. The heat release heat absorbing plate 7 is used to make the heat exchange with the wafer W uniform over the entire surface of the wafer W. Like the base plate 4 described above, the heat releasing plate 7 has a thermal conductivity such as aluminum or copper. It is configured in a rectangular flat plate shape with a high material, is joined to the upper surface of each Peltier element 6, and is screwed to the chamber constituting member 1 together with the base plate 4 by a pin 8. Although not clearly shown in the figure, the heads of the above-described pins 8 protrude from the upper surface of the heat dissipation plate 7 by about 0.1 mm, for example, and the wafer W is placed on the upper surface of the heat dissipation plate 7. In this case, an extremely slight gap is formed between them. Further, a heat panel may be used in place of the heat release heat absorbing plate 7.
[0019]
The fluid ejection pipe 5 has an ejection nozzle 9 at each distal end portion and an annular recess 10 at each outer peripheral portion, and each recess 10 faces the corresponding recess 2 and is ejected. A plurality (nine) of sealed fluids mounted on the chamber constituent member 1 with the nozzles 9 being close to the lower surface of the base plate 4 and separated from each other inside the chamber constituent member 1 together with the base plate 4 A supply chamber 11 is defined. As is apparent from the figure, a common supply pipe 12 is connected to the base ends of these fluid ejection pipes 5, while a common return pipe is connected to each recess 10 through a fluid return pipe 13. The path 14 is connected. In addition, the code | symbol 15 in a figure is a temperature sensor for detecting the temperature of the temperature fluid which passes along the return conduit 14.
[0020]
On the other hand, the temperature control device includes a high-temperature fluid circulation supply system 20 and a low-temperature fluid circulation supply system 30.
[0021]
The high-temperature fluid circulation supply system 20 is connected to the supply pipeline 12 via a high-temperature fluid supply valve 21 and is connected to the return pipeline 14 via a high-temperature fluid return valve 22. Is turned on, the temperature fluid stored in the high-temperature fluid heat storage tank 24 is circulated and supplied to each of the plurality of fluid supply chambers 11 by the operation of the high-temperature fluid supply pump 23. Although not shown in the drawing, the high-temperature fluid heat storage tank 24 is provided with heating means such as a heater, and operates to maintain and adjust the temperature fluid stored therein at a temperature in the vicinity of 150 ° C. Make it. The temperature fluid to be circulated is appropriately selected according to the target temperature to be controlled from liquids such as Fluorinert (registered trademark), ethylene glycol, oil and water, and gases such as nitrogen, air and helium. be able to. Reference numeral 25 in FIG. 1 is turned on when the supply of the temperature fluid is stopped, that is, when the high-temperature fluid supply valve 21 is turned off, and the temperature fluid in the high-temperature fluid heat storage tank 24 is circulated through the self-circulation supply system 26. For high temperature fluid circulation.
[0022]
The low-temperature fluid circulation supply system 30 is connected to the supply pipeline 12 via a low-temperature fluid supply valve 31 and is connected to the return pipeline 14 via a low-temperature fluid return valve 32. Is turned on, the temperature fluid stored in the low temperature fluid heat storage tank 34 is circulated and supplied to each of the plurality of fluid supply chambers 11 by the operation of the low temperature fluid supply pump 33. Although not shown in the drawing, the cryogenic fluid heat storage tank 34 has cooling means such as a chiller in its inside, and has the effect of maintaining and adjusting the temperature fluid stored therein at a temperature in the vicinity of 20 ° C. Make it. The temperature fluid to be circulated is controlled from liquids such as Fluorinert (registered trademark), ethylene glycol, oil and water, and gases such as nitrogen, air and helium, as in the case of the high-temperature fluid circulation and supply system 20. Although it is possible to appropriately select one according to the target temperature to be used, in the present embodiment, the same one as the high-temperature fluid circulation supply system 20 is applied. 1 is a low-temperature fluid circulation valve that is turned on when the low-temperature fluid supply valve 31 is turned off and circulates the temperature fluid in the low-temperature fluid heat storage tank 34 through the self-circulation system 36.
[0023]
Further, the temperature control device includes a valve drive control unit 40. The valve drive control unit 40 includes fluid supply valves 21 and 31, fluid return valves provided in the high-temperature fluid circulation supply system 20 and the low-temperature fluid circulation supply system 30, respectively, based on program data given in advance and two change temperatures. 22 and 32 and the fluid circulation valves 25 and 35 are controlled. Here, the two changed temperatures correspond to fluctuating temperatures that can be sufficiently relaxed and absorbed by the respective fluid heat storage tanks 24 and 34. The temperature of the low temperature fluid heat storage tank 34 is preset as T2 (hereinafter simply referred to as the second set temperature).
[0024]
Hereinafter, referring to FIG. 2 and FIG. 3 showing the processing contents of the valve drive control unit 40, in the temperature control apparatus, the temperature of the wafer W is calculated as a first target temperature TH and a second target temperature TC. An operation in the case of alternately controlling the temperature at intervals of 10 seconds, that is, a baking process in which the temperature of the wafer W is heated to 150 ° C. and a cooling process in which the temperature of the wafer W is subsequently cooled to 20 ° C. are alternately performed N times. The operation when executed will be described. As an initial state, in the above-described high-temperature fluid circulation supply system 20, the high-temperature fluid circulation valve 25 is turned on, and the high-temperature fluid fluid supply valve 21 and the high-temperature fluid fluid return valve 22 are both turned off. The temperature fluid stored in the high-temperature fluid heat storage tank 24 is circulated through the self-circulation system 26 by the operation of the high-temperature fluid supply pump 23 and is adjusted and maintained at a temperature near the target temperature. The low-temperature fluid supply valve 31 and the low-temperature fluid return valve 32 are turned on, and the low-temperature fluid circulation valve 35 is turned off, so that the low-temperature fluid is circulated and supplied to the fluid supply chamber 11 by the operation of the low-temperature fluid supply pump 33. It shall be.
[0025]
First, when the wafer W coated with resist is loaded from the initial state described above, and the wafer W is placed on the heat-dissipating and heat-dissipating plate 7 via the pins 8, the valve drive control unit 40 is illustrated, for example. Based on the detection signal from the non-existing sensor, it is determined that the high temperature fluid supply start state is set (step 51), the low temperature fluid supply valve 31 is turned OFF, and the high temperature fluid supply valve 21 is turned ON (step 52). As shown by ta in FIG. 3, the high-temperature fluid circulation valve 25 is turned OFF, the low-temperature fluid circulation valve 35 is turned ON, and a comparison is made as to whether or not the temperature detected by the temperature sensor 15 has reached the first set temperature T1. Is started (step 53).
[0026]
In this state, the operation of the high-temperature fluid supply pump 23 causes the high-temperature fluid near 150 ° C. stored in the high-temperature fluid heat storage tank 24 to be sequentially supplied to the fluid supply chamber 11.
[0027]
At that time, although the fluid supply chamber 11 is filled with the temperature fluid, forced convection is generated in the fluid supply chamber 11 by the temperature fluid ejected from the fluid ejection nozzle 9, and is always ejected from the fluid ejection nozzle 9. Since the temperature fluid collides with the lower surface of the base plate 4, the heat transfer coefficient of the lower surface of the base plate 4 is increased, and the base plate 4 to which the Peltier element 6 is joined is moved at a high speed. Can be heated to temperature.
[0028]
When the base plate 4 is heated, the heat is quickly transmitted to the wafer W through the Peltier element 6 and the heat dissipation / heat absorption plate 7, and the temperature of the wafer W is heated and maintained at 150 ° C. In this case, delicate temperature control is performed by driving the Peltier element 6. That is, the temperature of the base plate 4 or the heat dissipation plate 7 is detected by a temperature sensor (not shown), and the temperature of the wafer W is accurately set to the target temperature by driving the Peltier element 6 based on the detected temperature. I try to control it.
[0029]
During this time, before the temperature detected by the temperature sensor 15 reaches the first set temperature T1, the low temperature fluid return valve 32 continues to be in the ON state and the high temperature fluid return valve 22 continues to be in the OFF state. The low-temperature fluid remaining in the fluid supply chamber 11 and the return conduit 14 after the low-temperature fluid supply valve 31 when the fluid supply valves 21 and 31 are switched and the high-temperature fluid after the switching of the fluid supply valves 21 and 31 Any temperature fluid that has become so cold that it cannot be sufficiently relaxed and absorbed by the heat storage tank 24 is returned to the low temperature fluid heat storage tank 34 through the low temperature fluid return valve 32.
[0030]
On the other hand, when the temperature detected by the temperature sensor 15 reaches the first set temperature T1, the valve drive controller 40 turns off the low-temperature fluid return valve 32 at this time and turns on the high-temperature fluid return valve 22 (step 54 and Tb in FIG.
[0031]
Accordingly, the high-temperature fluid circulation supply system 20 is selectively connected to the fluid supply chamber 11 through the high-temperature fluid supply valve 21 and the high-temperature fluid return valve 22, and can be sufficiently relaxed and absorbed by the high-temperature fluid heat storage tank 24. The high-temperature fluid is returned to the high-temperature fluid heat storage tank 24.
[0032]
When the baking process performed by heating the wafer W to 150 ° C. by the above operation is completed, a cooling process for cooling the temperature of the wafer W to 20 ° C. is executed.
[0033]
That is, when the baking process is finished, the valve drive control unit 40 determines that the low-temperature fluid supply start state has been reached based on, for example, a detection signal from a sensor (not shown) (step 55), and turns the high-temperature fluid supply valve 21 on. On the other hand, the low temperature fluid supply valve 31 is turned on (step 56), and as shown in FIG. 3tc, the high temperature fluid circulation valve 25 is turned on, while the low temperature fluid circulation valve 35 is turned off. The comparison of whether or not the detected temperature has reached the second set temperature T2 is started (step 57).
[0034]
In this state, the operation of the low temperature fluid supply pump 33 causes the low temperature fluid near 20 ° C. stored in the low temperature fluid heat storage tank 34 to be sequentially supplied to the fluid supply chamber 11. Then, the temperature of the wafer W is cooled to near the temperature of the fluid, and the heat of the wafer W is dissipated through the heat dissipation plate 7, the Peltier element 6, and the base plate 4, and the temperature of the wafer W is cooled to 20 ° C. Will be maintained. Even in this cooling, delicate temperature control is performed by driving the Peltier element 6.
[0035]
During this time, before the temperature detected by the temperature sensor 15 reaches the second set temperature T2, the high temperature fluid return valve 22 is continuously in the ON state and the low temperature fluid return valve 32 is continuously in the OFF state. The high-temperature fluid remaining in the fluid supply chamber 11 and the return conduit 14 after the high-temperature fluid supply valve 21 when the fluid supply valves 21 and 31 are switched, and the low-temperature fluid after the switching of the fluid supply valves 21 and 31 as well. Any temperature fluid that has become so hot that it cannot be sufficiently relaxed and absorbed by the heat storage tank 34 is returned to the heat storage tank 24 for the high temperature fluid through the high temperature fluid return valve 22.
[0036]
On the other hand, when the temperature detected by the temperature sensor 15 reaches the second set temperature T2, the valve drive control unit 40 turns off the high-temperature fluid return valve 22 at this time and turns on the low-temperature fluid return valve 32 (steps 58 and 58). Td in FIG.
[0037]
In this state, the low-temperature fluid circulation supply system 30 is selectively connected to the fluid supply chamber 11 through the low-temperature fluid supply valve 31 and the low-temperature fluid return valve 32, and can be sufficiently relaxed and absorbed by the low-temperature fluid heat storage tank 34. The temperature fluid that has become as low as possible is returned to the low-temperature fluid heat storage tank 34.
[0038]
As described above, when the cooling process of the wafer W is completed and the wafer W is replaced with a new wafer W, the procedure for performing the baking process and the cooling process on the new wafer W in the same manner is performed. After the process is returned to 51 and the above-described operation is repeated a total of N times, the procedure ends (step 60).
[0039]
As described above, according to the temperature control device, after the fluid supply valves 21 and 31 are switched, the temperature of the temperature fluid returned from the fluid supply chamber 11 reaches the preset temperatures T1 and T2, respectively. Since the fluid return valves 22 and 32 are switched, the temperature fluid remaining between the fluid supply valves 21 and 31 and the fluid return valves 22 and 32 at the time of switching the fluid supply valves 21 and 31 There is no possibility that a temperature fluid having a temperature fluctuation that cannot be absorbed is mixed into the fluid heat storage tanks 24 and 34, and a large temperature fluctuation of the fluid circulation supply systems 20 and 30 due to the mixing of different temperature fluids. Can be prevented.
[0040]
FIG. 4 shows a second embodiment of the temperature control device according to the present invention. In the second embodiment, similarly to the first embodiment described above, in the semiconductor manufacturing process for forming a resist film through the processes (1) to (8) described above, a pre-baking + cooling process, or Used in the post-baking + cooling process, a cycle in which the wafer W is first heated to a high temperature (baking process) and then cooled to room temperature (cooling process) is repeated at intervals of several tens of seconds for each wafer. It is for performing control, and the processing content of the valve drive control unit 70 is different from that of the first embodiment.
[0041]
That is, the valve drive control unit 70 of the second embodiment is provided in each of the high-temperature fluid circulation supply system 20 and the low-temperature fluid circulation supply system 30 based on program data given in advance and two preset delay times. The fluid supply valves 21 and 31, the fluid return valves 22 and 32, and the fluid circulation valves 25 and 35 are controlled. Here, the two delay times are times until the temperature detected by the temperature sensor 15 reaches the above-described two changed temperatures T1 and T2 after changing the temperature fluid supplied to the fluid supply chamber 11. The time from when the low temperature fluid is changed to the high temperature fluid until the temperature detected by the temperature sensor 15 rises to the change temperature T1 of the high temperature fluid heat storage tank 24 is set as the first delay time t1, while The time from when the temperature is changed to fluid to when the temperature detected by the temperature sensor 15 falls to the change temperature T2 of the low-temperature fluid heat storage tank 34 is set as the second delay time t2.
[0042]
Hereinafter, referring to FIG. 5 and FIG. 6 showing the processing contents of the valve drive control unit 70, in the temperature control apparatus, the temperature of the wafer W is set to the first target temperature TH (= 150 ° C.) and the second target temperature. The operation in the case of temperature control alternately with the temperature TC (= 20 ° C.) at intervals of several tens of seconds will be described. In addition, about the structure similar to 1st Embodiment, the same code | symbol is attached | subjected and each detailed description is abbreviate | omitted. In the initial state, as in the first embodiment, in the high-temperature fluid circulation supply system 20, the high-temperature fluid circulation valve 25 is turned on, and the high-temperature fluid fluid supply valve 21 and the high-temperature fluid fluid return valve 22 are turned on. Both are turned off, and the temperature fluid stored in the high-temperature fluid heat storage tank 24 by the operation of the high-temperature fluid supply pump 23 circulates in the self-circulation system 26 and is adjusted and maintained at a temperature near the target temperature. In the fluid circulation supply system 30, the low-temperature fluid supply valve 31 and the low-temperature fluid return valve 32 are turned on, and the low-temperature fluid circulation valve 35 is turned off. It is assumed that fluid is circulated and supplied.
[0043]
First, when the wafer W coated with a resist is loaded from the initial state described above, and the wafer W is placed on the heat-dissipating and heat-dissipating plate 7 via the pins 8, the valve drive control unit 70 is illustrated, for example. Based on the detection signal from the non-existing sensor, it is determined that the high-temperature fluid supply is started (step 81), the low-temperature fluid supply valve 31 is turned off, and the high-temperature fluid supply valve 21 is turned on (step 82). As shown by ta ′ in FIG. 6, the high temperature fluid circulation valve 25 is turned OFF, the low temperature fluid circulation valve 35 is turned ON, and the time measurement from the time when the high temperature fluid supply valve 21 is turned ON is started (step). 83).
[0044]
In this state, the operation of the high-temperature fluid supply pump 23 causes the high-temperature fluid near 150 ° C. stored in the high-temperature fluid heat storage tank 24 to be sequentially supplied to the fluid supply chamber 11. The wafer W is quickly heated and maintained at a temperature of 150 ° C. via the Peltier element 6 and the heat release / absorption plate 7.
[0045]
During this time, before the elapsed time from when the high temperature fluid supply valve 21 is turned on reaches the first delay time t1, the low temperature fluid return valve 32 continues to be in the ON state, and the high temperature fluid return valve 22 continues. Therefore, the low temperature fluid remaining in the fluid supply chamber 11 and the return conduit 14 after the low temperature fluid supply valve 31 when the fluid supply valves 21 and 31 are switched, and the fluid supply valves 21 and 31 are switched off. Even after switching, the temperature fluid that has become so low that it cannot be sufficiently relaxed and absorbed by the high-temperature fluid heat storage tank 24 is returned to the low-temperature fluid heat storage tank 34 through the low-temperature fluid return valve 32. become.
[0046]
On the other hand, when the elapsed time from when the high temperature fluid supply valve 21 is turned on reaches the first delay time t1, the valve drive control unit 70 turns off the low temperature fluid return valve 32 at this time, while the high temperature fluid return valve 22 is turned off. Is turned on (step 84 and tb ′ in FIG. 6).
[0047]
Accordingly, the high-temperature fluid circulation supply system 20 is selectively connected to the fluid supply chamber 11 through the high-temperature fluid supply valve 21 and the high-temperature fluid return valve 22, and can be sufficiently relaxed and absorbed by the high-temperature fluid heat storage tank 24. The high-temperature fluid is returned to the high-temperature fluid heat storage tank 24.
[0048]
When the baking process performed by heating the wafer W to 150 ° C. by the above operation is completed, a cooling process for cooling the temperature of the wafer W to 20 ° C. is executed.
[0049]
That is, when the baking process is completed, the valve drive control unit 70 determines that the low-temperature fluid supply start state has been reached, for example, based on a detection signal from a sensor (not shown) (step 85), and turns the high-temperature fluid supply valve 21 on. On the other hand, the low temperature fluid supply valve 31 is turned on (step 86). Further, as shown by tc 'in FIG. 6, the high temperature fluid circulation valve 25 is turned on, while the low temperature fluid circulation valve 35 is turned off. Time measurement from the time when the low-temperature fluid supply valve 31 is turned on is started (step 87).
[0050]
In this state, since the low temperature fluid near 20 ° C. stored in the low temperature fluid heat storage tank 34 is sequentially supplied to the fluid supply chamber 11 by the operation of the low temperature fluid supply pump 33, the heat of the wafer W is absorbed by the heat dissipation heat plate. 7, the heat is dissipated through the Peltier element 6 and the base plate 4, and the temperature of the wafer W is kept cooled to 20 ° C.
[0051]
During this time, before the elapsed time from when the low temperature fluid supply valve 31 is turned on reaches the second delay time t2, the high temperature fluid return valve 22 continues to be in the ON state, and the low temperature fluid return valve 32 continues. Since the fluid supply valves 21 and 31 are switched, the high temperature fluid remaining in the fluid supply chamber 11 and the return conduit 14 after the high temperature fluid supply valve 21 and the fluid supply valves 21 and 31 are switched. Even after switching, any temperature fluid that has become so hot that it cannot be sufficiently relaxed and absorbed by the low temperature fluid heat storage tank 34 is returned to the high temperature fluid heat storage tank 24 through the high temperature fluid return valve 22. become.
[0052]
On the other hand, when the elapsed time from when the low-temperature fluid supply valve 31 is turned on reaches the second delay time t2, the valve drive control unit 70 turns off the high-temperature fluid return valve 22 at this time, while the low-temperature fluid return valve 32 is turned off. Is turned on (step 88 and td 'in FIG. 6).
[0053]
In this state, the low-temperature fluid circulation supply system 30 is selectively connected to the fluid supply chamber 11 through the low-temperature fluid supply valve 31 and the low-temperature fluid return valve 32, and can be sufficiently relaxed and absorbed by the low-temperature fluid heat storage tank 34. The temperature fluid that has become as low as possible is returned to the low-temperature fluid heat storage tank 34.
[0054]
As described above, when the cooling process of the wafer W is completed and the wafer W is replaced with a new wafer W, the procedure for performing the baking process and the cooling process on the new wafer W in the same manner is performed. After returning to 81 and repeating the above-described operation for a total of N times, the procedure ends (step 90).
[0055]
As described above, according to the temperature control device, after the fluid supply valves 21 and 31 are switched, the fluid return valves 22 and 32 are switched when the respective preset delay times t1 and t2 have elapsed. Therefore, when the fluid supply valves 21 and 31 are switched, the temperature fluid remaining between the fluid supply valves 21 and 31 and the fluid return valves 22 and 32 or the temperature fluid having temperature fluctuations that cannot be relaxed / absorbed. Can be prevented from entering the fluid heat storage tanks 24 and 34, and large temperature fluctuations in the fluid circulation supply systems 20 and 30 due to the mixing of different temperature fluids can be prevented.
[0056]
In each of the above-described embodiments, the temperature control device that controls the temperature of the wafer W in the semiconductor manufacturing process is exemplified. However, the present invention can also be applied to the case where the temperature control of other temperature control objects is performed. Of course you can. In this case, the target temperature does not necessarily have to be two, that is, the number of fluid circulation supply systems does not necessarily have to be two, and any number of target temperatures may be used.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a first embodiment of a temperature control device according to the present invention.
FIG. 2 is a flowchart showing a processing procedure of a valve drive control unit shown in FIG.
3 is a timing chart showing the operation timing of each valve in the circuit diagram shown in FIG. 1. FIG.
FIG. 4 is a circuit diagram showing a second embodiment of the temperature control device according to the present invention.
FIG. 5 is a flowchart showing a processing procedure of the valve drive control unit shown in FIG. 4;
6 is a timing chart showing the operation timing of each valve in the circuit diagram shown in FIG. 4. FIG.
[Explanation of symbols]
11 ... Fluid supply chamber
20 ... High-temperature fluid circulation supply system
21 ... High temperature fluid supply valve
22 ... High temperature fluid return valve
30 ... Low-temperature fluid circulation supply system
31 ... Low temperature fluid supply valve
32 ... Cryogenic fluid return valve
40, 70 ... Valve drive control unit
W ... wafer

Claims (4)

A plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, and the plurality of fluid circulation supply systems and the object to be controlled are interposed between the plurality of fluid circulation supply systems. A supply selection means for selecting a supply destination of the temperature fluid from the fluid circulation supply system to the object to be controlled, and a plurality of the fluid circulation supply system and the object to be controlled. A return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from the fluid circulation supply system of the same, and the same fluid circulation supply system is selected by the supply selection means and the return selection means In the temperature control device that circulates and supplies a desired temperature fluid to the object to be controlled, and performs temperature control of the object to be controlled,
After the fluid circulation supply system is changed by the supply selection means, the temperature of the temperature fluid returned from the object to be controlled is detected, and when the detected temperature reaches the preset change temperature, the temperature fluid A temperature control device characterized in that means for operating the return selection means is provided to change the return destination to the same fluid circulation supply system. A plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, and the plurality of fluid circulation supply systems and the object to be controlled are interposed between the plurality of fluid circulation supply systems. A supply selection means for selecting a supply destination of the temperature fluid from the fluid circulation supply system to the object to be controlled, and a plurality of the fluid circulation supply system and the object to be controlled. A return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from the fluid circulation supply system of the same, and the same fluid circulation supply system is selected by the supply selection means and the return selection means In the temperature control device that circulates and supplies a desired temperature fluid to the object to be controlled, and performs temperature control of the object to be controlled,
When the elapsed time from the time when the fluid circulation supply system is changed by the supply selection means reaches a preset time, the return destination of the temperature fluid supplied to the temperature controlled object is set to the same fluid circulation supply system. A temperature control device characterized in that means for operating the return selection means is provided for changing. A plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, and the plurality of fluid circulation supply systems and the object to be controlled are interposed between the plurality of fluid circulation supply systems. A supply selection means for selecting a supply destination of the temperature fluid from the fluid circulation supply system to the object to be controlled, and a plurality of the fluid circulation supply system and the object to be controlled. A return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from the fluid circulation supply system of the same, and the same fluid circulation supply system is selected by the supply selection means and the return selection means In the temperature control method for circulatingly supplying a desired temperature fluid to the object to be controlled and performing temperature control of the object to be controlled,
When the temperature of the temperature fluid returned from the object to be controlled reaches the preset change temperature after changing the fluid circulation supply system by the supply selection means, the return destination of the temperature fluid is the same fluid circulation A temperature control method comprising operating the return selection means to change to a supply system. A plurality of fluid circulation supply systems that circulate and supply temperature fluids having different set temperatures to the object to be controlled, and the plurality of fluid circulation supply systems and the object to be controlled are interposed between the plurality of fluid circulation supply systems. A supply selection means for selecting a supply destination of the temperature fluid from the fluid circulation supply system to the object to be controlled, and a plurality of the fluid circulation supply system and the object to be controlled. A return selection means for selecting a return destination of the temperature fluid supplied to the object to be controlled from the fluid circulation supply system of the same, and the same fluid circulation supply system is selected by the supply selection means and the return selection means In the temperature control method for circulatingly supplying a desired temperature fluid to the object to be controlled and performing temperature control of the object to be controlled,
In order to change the return destination of the temperature fluid supplied to the object to be controlled to the same fluid circulation supply system with a preset time delay from the time when the fluid circulation supply system is changed by the supply selection means. A temperature control method characterized by operating a selection means.

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