Temperature control system

Abstract

To prevent a component from being damaged due to a sudden temperature change during temperature control while shortening a temperature control time.SOLUTION: The temperature control system 100 includes the fluid supply controller 150 having the first chiller 110 that controls the temperature of the first fluid, the second chiller 120 that controls the temperature of the second fluid, the temperature adjustment unit 151 that heats or cools the first fluid or the second fluid introduced into the temperature control base 14 to a target temperature, and the flow direction switching unit 152 that controls the flow direction of each fluid. The flow direction switching part 152 makes the second fluid flow in a first direction from the center side to the outer peripheral side of the temperature control base 14 at the time of temperature rise, and makes the first fluid flow in a second direction from the outer peripheral side to the center side of the temperature control base 14 at the time of temperature fall.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a temperature control system connected to a plasma processing apparatus for performing plasma etching processing. [Background technology]

[0002] In the etching process of semiconductor manufacturing for 3D NAND memory and DRAM, high aspect ratio etching technology is required. One method for increasing the etching rate in the etching process is cryo-etching, which is dry etching in an extremely low temperature environment (cryoenvironment) of -40°C or below.

[0003] In such processes, reaction products (deposits) generated during the etching process adhere to and accumulate on all exposed surfaces inside the vacuum chamber. These deposits can peel off during the etching process and adhere to the workpiece, causing defects, so a deposit removal process is carried out after the etching process is completed.

[0004] For example, plasma cleaning is known as a removal process, which uses O2 plasma to remove deposits. In plasma cleaning, the higher the temperature, the more efficient the removal. Therefore, in the removal process, it is desirable to raise the temperature of the low-temperature holding plate maintained in a cryogenic environment.

[0005] The following Patent Document 1 discloses a temperature control method and a plasma processing apparatus that aim to shorten the time required to remove deposits inside a vacuum chamber using plasma as described above. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-145095 Summary of the Invention [Problem to be solved by the invention]

[0007] In plasma processing equipment, the performance required when switching the holding plate that holds the workpiece from low to high temperatures includes shortening the process time and switching at high throughput so as not to impede productivity, preventing damage to parts due to temperature changes, etc. In addition, the fluid that controls the temperature of the holding plate increases the etching rate of the plasma etching and improves the efficiency of the removal process, so it is preferable to set the low temperature to -50°C or below and the high temperature to 50°C or above, and to switch between low and high temperatures quickly in order to improve throughput.

[0008] However, with the technology of Patent Document 1, if fluids with a wide temperature range such as those described above are switched between, the sudden exchange of low-temperature and high-temperature fluids causes uneven temperature distribution in the holding plate, making it highly likely to be damaged by thermal stress.

[0009] Furthermore, in the technology of Patent Document 1, one method of reducing uneven temperature distribution is to control the temperature of the fluid by gradually changing it, for example, but this has the problem of taking a long time to reach the target temperature, which reduces productivity.

[0010] The object of the present invention has been made in consideration of the above-mentioned problems, and specifically, to provide a temperature control system that can shorten the temperature control time while preventing damage to components due to sudden temperature changes during temperature control. [Means for solving the problem]

[0011] The above object can be achieved by any one of the following means (1) to (13).

[0012] (1) A plasma processing apparatus connectable to a plasma processing apparatus capable of performing plasma etching on a workpiece in a vacuum chamber, the plasma processing apparatus comprising: a holding plate for holding the workpiece placed on a placement surface; a temperature control base joined to the holding plate and having a flow path formed therein through which a fluid can flow so that the holding plate is at a target temperature; a lower housing for holding the temperature control base in the vacuum chamber; a first chiller for supplying a first fluid controlled to a predetermined temperature; a second chiller for supplying a second fluid controlled to a temperature different from that controlled by the first chiller; and at least a pre-cooling device for supplying a first fluid from the first chiller. a fluid supply control unit that selectively supplies the first fluid and the second fluid from the second chiller to the temperature control base, wherein the fluid supply control unit has a temperature adjustment unit that heats or cools the first fluid or the second fluid introduced into the temperature control base to the target temperature, and a flow direction switching unit that controls the flow direction of each fluid, wherein the flow direction switching unit circulates the second fluid in a first direction from the center to the outer periphery of the temperature control base when the temperature is rising, and circulates the first fluid in a second direction from the outer periphery to the center of the temperature control base when the temperature is falling.

[0013] (2) A plasma processing apparatus connectable to a plasma processing apparatus capable of performing plasma etching on a workpiece in a vacuum chamber, the plasma processing apparatus comprising: a holding plate for holding the workpiece placed on a placement surface; a temperature control base joined to the holding plate and having a flow path formed therein through which a fluid can flow so that the holding plate reaches a target temperature; a lower housing for holding the temperature control base in the vacuum chamber; a first chiller for supplying a first fluid controlled to a predetermined temperature; a second chiller for supplying a second fluid controlled to a temperature different from that controlled by the first chiller; and a second chiller for supplying the second fluid in a first direction from the center side toward the outer periphery of the temperature control base when the temperature is increased, and a second chiller for supplying a second fluid controlled to a temperature different from that controlled by the first chiller when the temperature is decreased. a high-temperature maintenance storage unit that stores a third fluid adjusted to a temperature higher than the target temperature and has a fluid flow port that supplies the third fluid; and a temperature rise / fall control unit that includes at least the first chiller and the second chiller, wherein the fluid flow port of the high-temperature maintenance storage unit is disposed between the temperature control base and the temperature rise / fall control unit, and the flow direction switching unit, when starting to rise in temperature, causes the third fluid to flow through the fluid flow port in a first direction from the center to the outer periphery of the temperature control base, and stops the flow of the third fluid at a predetermined timing, and then causes the second fluid to flow in the first direction.

[0014] (3) A temperature control system as described in (1) or (2) above, having a storage section arranged upstream of the first chiller and the second chiller, which stores the return fluid from the temperature control base, adjusts it to be equivalent to the control temperature of the first chiller or the second chiller, and then returns it to the first chiller or the second chiller.

[0015] (4) The temperature control system described in (3) above, wherein the storage unit includes: a first storage unit arranged upstream of the first chiller, storing the return fluid from the temperature control base, adjusting the temperature of the return fluid to be equivalent to the control temperature by the first chiller, and then returning it to the first chiller; and a second storage unit arranged upstream of the second chiller, storing the return fluid from the temperature control base, adjusting the temperature of the return fluid to be equivalent to the control temperature by the second chiller, and then returning it to the second chiller.

[0016] (5) A temperature control system as described in (4) above, wherein the first storage unit circulates the stored return fluid between the first chiller and the second chiller to adjust the temperature to be equivalent to the control temperature of the first chiller, and the second storage unit circulates the stored return fluid between the second chiller and the second chiller to adjust the temperature to be equivalent to the control temperature of the second chiller.

[0017] (6) A temperature control system as described in (1) or (2) above, which has a common storage unit for storing return fluid from the temperature control base, and when the temperature of the return fluid is different from the control temperature of the first chiller or the second chiller, the common storage unit stores the return fluid and circulates a fluid of the same temperature as the first chiller or the second chiller to the first chiller or the second chiller, and when the temperature of the return fluid stored in the common storage unit becomes equal to the control temperature of the first chiller or the second chiller, the return fluid is circulated directly to the first chiller or the second chiller.

[0018] (7) The temperature control system described in (6) above, wherein the common storage unit circulates the stored return fluid between the first chiller and the common storage unit during high temperature maintenance operation to adjust the temperature to the control temperature of the first chiller, and circulates the stored return fluid between the second chiller and the common storage unit during low temperature maintenance operation to adjust the temperature to the control temperature of the second chiller.

[0019] (8) The temperature control system described in (2) above, wherein the high temperature maintenance storage unit is arranged between the temperature control base and the temperature rise / fall control unit, and the fluid flow port of the high temperature maintenance storage unit is arranged between the temperature control base and the flow direction switching unit.

[0020] (9) A temperature control system as described in (1) or (2) above, which has a gas supply unit that circulates an inert exhaust gas through the flow path to exhaust the fluid in the flow path to the outside when switching the fluid circulating through the temperature control base to another fluid.

[0021] (10) A temperature control system as described in (3) above, having a bypass path for returning the return fluid directly to the first chiller or the second chiller without passing through the storage section when the return fluid becomes equivalent to the control temperature of the first chiller or the second chiller.

[0022] (11) A temperature control system as described in (6) above, having a bypass path for returning the fluid from the flow path directly to the first chiller or the second chiller without passing through the common storage section when the fluid returning from the flow path becomes equivalent to the control temperature of the first chiller or the second chiller.

[0023] (12) The flow path extends in a circular pattern from the outer periphery toward the center inside the temperature control base, and has a first flow port that guides the fluid toward the center of the flow path when fluid flow begins, and a second flow port that guides the fluid toward the outer periphery of the flow path when flow begins, and the flow direction switching unit circulates the second fluid in the first direction from the first flow port toward the second flow port of the temperature control base when the temperature increases, and circulates the first fluid in the second direction from the second flow port toward the first flow port when the temperature decreases, in the temperature control system described in (1) or (2) above.

[0024] (13) A temperature control system according to any one of (1) to (11) above, wherein the holding plate is an electrostatic chuck having a plurality of convex portions formed on the mounting surface and incorporating an electrode for electrostatically attracting and holding the workpiece. [Effects of the Invention]

[0025] According to the present invention, it is possible to reduce the temperature control time while preventing damage to components due to abrupt temperature changes during temperature control. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a schematic configuration diagram of a plasma processing apparatus to which a temperature control system according to an embodiment of the present invention is connected; [Figure 2] 1 is a functional block diagram of a temperature control system according to a first embodiment of the present invention. [Figure 3A] FIG. 2 is a diagram showing a first direction of a flow channel. [Figure 3B] FIG. 10 is a diagram showing a second direction of the flow channel. [Figure 4A] FIG. 4 is a diagram showing the flow of fluid during low temperature maintenance operation of the temperature control system of the first embodiment. [Figure 4B] FIG. 4 is a diagram showing the flow of fluid during the temperature increasing operation of the temperature control system of the first embodiment. [Figure 4C] FIG. 4 is a diagram showing the flow of fluid during high temperature maintenance operation of the temperature control system of the first embodiment. [Figure 4D] FIG. 4 is a diagram showing the flow of fluid during the temperature lowering operation of the temperature control system of the first embodiment. [Figure 5] FIG. 5 is a functional block diagram of a temperature control system according to a second embodiment of the present invention. [Figure 6A] FIG. 10 is a diagram showing the flow of fluid during low temperature maintenance operation of the temperature control system according to the second embodiment. [Figure 6B] FIG. 10 is a diagram showing the flow of fluid during the temperature increasing operation of the temperature control system according to the second embodiment. [Figure 6C] FIG. 10 is a diagram showing the flow of fluid during high temperature maintenance operation of the temperature control system according to the second embodiment. [Figure 6D] FIG. 10 is a diagram showing the flow of fluid during the temperature lowering operation of the temperature control system according to the second embodiment. [Figure 7] FIG. 10 is a functional block diagram of a temperature control system according to a third embodiment of the present invention. [Figure 8A] FIG. 10 is a diagram showing the flow of fluid during low temperature maintenance operation of the temperature control system of the third embodiment. [Figure 8B] FIG. 10 is a diagram showing the flow of fluid during the temperature increasing operation of the temperature control system according to the third embodiment. [Figure 8C] FIG. 10 is a diagram showing the flow of fluid during high temperature maintenance operation of the temperature control system of the third embodiment. [Figure 8D] FIG. 10 is a diagram showing the flow of fluid during the temperature lowering operation of the temperature control system according to the third embodiment. [Figure 9A] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 10 seconds have elapsed, which is a simulation result of an example. [Figure 9B] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 20 seconds have elapsed, which is a simulation result of an example. [Figure 9C] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 30 seconds have elapsed, which is a simulation result of an example. [Figure 9D] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 60 seconds have elapsed, which is a simulation result of an example. [Figure 10A] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 10 seconds have elapsed, which is a simulation result of the comparative example. [Figure 10B] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 20 seconds have elapsed, which is a simulation result of the comparative example. [Figure 10C] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 30 seconds have elapsed, which is a simulation result of the comparative example. [Figure 10D] FIG. 10 is a diagram showing the temperature distribution of the electrostatic chuck after 60 seconds have elapsed, which is a simulation result of an example. [Figure 11A] 10 is a simulation result showing stress distribution in the electrostatic chuck of the example. [Figure 11B] 10 is a simulation result showing stress distribution in an electrostatic chuck of a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience. Meanwhile, the embodiments described below are merely examples, and various modifications are possible from such embodiments.

[0028] Hereinafter, the terms "upper" and "above" may include not only what is directly above in contact with something, but also what is above without contact. Similarly, the terms "lower" and "below" may include not only what is directly below in contact with something, but also what is below without contact.

[0029] The singular expression includes the plural expression unless the context clearly dictates otherwise. Furthermore, when a part "includes," "comprises," or "has" a certain element, it does not mean that it excludes other elements, but that it may further include other elements, unless otherwise specified to the contrary.

[0030] Unless explicitly stated or stated to the contrary, steps constituting a method may be performed in any suitable order, and are not necessarily limited to the order of the steps described. The use of any examples or exemplary terms is merely for the purpose of illustrating the technical idea, and the scope of the invention is not limited by the examples or exemplary terms, except as limited by the scope of the claims.

[0031] In the following description, when ordinal numbers such as "first" and "second" are used, unless otherwise specified, they are used for convenience and do not stipulate any particular order.

[0032] A temperature control system 100 according to a first embodiment of the present invention will be described.

[0033] The temperature control system 100 can be connected to a plasma processing apparatus 1 capable of performing plasma etching processing. The temperature control system 100 controls the temperature of an electrostatic chuck 13, which functions as a holding plate and is disposed on a stage 11 of the plasma processing apparatus 1, to a target temperature.

[0034] 1 shows a plasma processing apparatus 1 to which a temperature control system 100 is connected. FIG. 2 shows a block diagram illustrating the fluid flow in the temperature control system 100.

[0035] As shown in FIG. 1, the plasma processing apparatus 1 includes an apparatus main body 2 and a control device 3. The apparatus main body 2 is divided into an upper housing 2a and a lower housing 2b, and a plasma processing space PS is formed inside. The upper housing 2a and the lower housing 2b are stacked vertically to form a vacuum chamber 10, which serves as a processing container for performing a predetermined plasma processing on a workpiece W, such as a disk-shaped semiconductor wafer made of silicon or other base material. An exhaust path 17 is formed in the vacuum chamber 10. An exhaust device 18 is connected to the exhaust path 17 via an exhaust pipe. The exhaust device 18 has, for example, a vacuum pump and can reduce the pressure inside the vacuum chamber 10 to a predetermined vacuum level.

[0036] The control device 3 is configured to include various processors, memories, input / output interfaces, etc. The control device 3 executes a predetermined program read from the memory in the processor and outputs control instructions to the controlled object via the input / output interface. This allows the plasma processing device 1 to perform a predetermined plasma process such as etching on the workpiece W. The control device 3 also comprehensively controls the drive of each part of the temperature control system 100 connected to the plasma processing device 1 (control of the flow direction of fluid, temperature control, etc.).

[0037] A stage 11 on which a workpiece W to be processed is placed is provided in the vacuum chamber 10. The stage 11 has a lower electrode 12, an electrostatic chuck 13, and a temperature control base 14.

[0038] The lower electrode 12 is made of, for example, aluminum, and is supported at the bottom of the vacuum chamber 10 via an insulating member. The lower electrode 12 is paired with an upper electrode 20. A temperature control base 14 is disposed above the lower electrode 12. High-frequency power is supplied to the lower electrode 12 from a high-frequency power supply 12a.

[0039] The electrostatic chuck 13 is a holding plate that has an electrode 13a, which is a conductive film, and a pair of insulating plates 13b made of ceramics such as Al2O3 that sandwich the electrode 13a, and that electrostatically attracts and fixes the workpiece W. The surface of the electrostatic chuck 13 on which the workpiece W is placed can be formed with multiple protrusions to control particle adhesion, etc. The electrostatic chuck 13 is connected to a DC power supply 13c and an HV terminal 13d. The DC power supply 13c supplies the high voltage required to electrostatically attract and fix the workpiece W to the electrostatic chuck 13 via the HV terminal 13d.

[0040] A heat transfer gas, such as He gas, is supplied to the electrostatic chuck 13 via a gas pipe 16c. The heat transfer gas is supplied between the electrostatic chuck 13 and the workpiece W. The thermal conductivity between the electrostatic chuck 13 and the workpiece W can be adjusted by adjusting the supply pressure of the heat transfer gas.

[0041] Temperature control base 14 is made of a metal such as Ti or Nb, and is disposed between lower electrode 12 and electrostatic chuck 13 and bonded to electrostatic chuck 13. Temperature control base 14 has flow path 15 formed therein through which a fluid can flow in order to control the temperature of electrostatic chuck 13. Note that the material of temperature control base 14 is preferably selected from a substance that has a small difference in thermal expansion with the material of electrostatic chuck 13, and the material may be non-metallic.

[0042] The fluid flowing through the flow path 15 is a low-temperature / high-temperature fluid such as a first fluid or a second fluid that functions as a heat transfer medium, or an inert compressed gas (discharge gas) for discharging the fluid in the flow path 15 to the outside of the flow path 15. The flow path 15 is connected to a flow direction switching unit 152 of a fluid supply control unit 150 (described later) via pipes 16a and 16b. The fluid is supplied from the temperature control system 100 to the flow path 15 via pipe 16a or pipe 16b. The fluid that has flowed through the flow path 15 is returned to the temperature control system 100 via pipe 16a or pipe 16b.

[0043] The flow path 15 extends from the center of the temperature control base 14 to the outer periphery. As shown in FIGS. 3A and 3B, the flow path 15 has a first flow port 15a that guides the fluid toward the center of the flow path 15 when the fluid starts to flow, and a second flow port 15b that guides the fluid toward the outer periphery of the flow path 15 when the fluid starts to flow. The flow path 15 shown in FIGS. 3A and 3B is formed so as to connect the first flow port 15a formed near the center to the second flow port 15b formed from the center to the outer periphery in a spiral shape that is approximately concentric with the entire temperature control base 14 in a single stroke. In this embodiment, the first flow port 15a is connected to the pipe 16a, and the second flow port 15b is connected to the pipe 16b.

[0044] 3A and 3B are conceptual diagrams for explaining the function of the flow path 15, and are not limited to the illustrated form. The flow path 15 may be a single flow path that extends around the entire temperature control base 14 from the center toward the outer periphery. Therefore, the flow path 15 may have a shape that meanders or is partially folded back, for example.

[0045] The fluid flowing through the temperature control base 14 can flow in two directions: a "first direction" from the center toward the outer periphery of the temperature control base 14, and a "second direction" from the outer periphery toward the center of the temperature control base 14. In this embodiment, the first direction is the direction in which the fluid flows in through the first flow port 15a of the flow path 15 and flows out through the second flow port 15b, as shown in FIG. 3A. In this embodiment, the second direction is the direction in which the fluid flows in through the second flow port 15b of the flow path 15 and flows out through the first flow port 15a, as shown in FIG. 3B.

[0046] The flow direction of the fluid through the flow path 15 can be switched as appropriate by control of a flow direction switching unit 152, which will be described later. In this embodiment, the low-temperature fluid flows in the second direction, and the high-temperature fluid flows in the first direction. That is, the low-temperature first fluid flowing out from the first chiller 110, which will be described later, flows into the flow path 15 from the second flow port 15b along the second direction and flows out from the first flow port 15a. The high-temperature second fluid flowing out from the second chiller 112, which will be described later, flows into the flow path 15 from the first flow port 15a along the first direction and flows out from the second flow port 15b. The exhaust gas that pushes the fluid remaining in the flow path 15 to the outside may be circulated in either the first direction or the second direction.

[0047] The vacuum chamber 10 has lift pins 19 that can move up to above the mounting surface of the electrostatic chuck 13. The lift pins 19 are configured to be movable up and down by a drive mechanism (not shown). The workpiece W is transported onto the stage 11 by a transport device (not shown) and is then transferred onto the lift pins 19 that have moved up to above the mounting surface of the electrostatic chuck 13. Then, after the lift pins 19 are lowered and the workpiece W is placed on the mounting surface of the electrostatic chuck 13, the workpiece W is attracted and held by the electrostatic chuck 13 by electrostatic force generated by DC power applied from a DC power source 13c.

[0048] An upper electrode 20 is disposed above the stage 11 at a position facing the stage 11. The upper electrode 20 is disposed so as to be substantially parallel to the lower electrode 12. Plasma is generated in the space between the upper electrode 20 and the lower electrode 12, and the generated plasma is used to perform plasma processing such as etching on the workpiece W held on the electrostatic chuck 13.

[0049] The upper electrode 20 can be formed of a shower head serving as a gas introduction unit. The shower head is configured to introduce at least one processing gas from a processing gas supply unit (not shown) into the plasma processing space PS. The shower head has at least one gas supply port, at least one gas diffusion chamber, and multiple gas introduction ports.

[0050] Next, the temperature control system 100 will be described.

[0051] The temperature control system 100 is connected to the plasma processing apparatus 1, and controls the temperature of a holding plate (electrostatic chuck 13) on which a workpiece W to be plasma processed is placed via a temperature control base 14. Each component of the temperature control system 100 is driven and controlled in accordance with a predetermined operation program under the control of a control device 3.

[0052] The temperature control system 100 includes a first chiller 110, a second chiller 120, a storage unit 130, a fluid discharge unit 140, and a fluid supply control unit 150. The temperature control system 100 can also include a temperature control base 14 through which the fluids (first fluid, second fluid) flowing out from the first chiller 110 and the second chiller 120.

[0053] For ease of explanation, the temperature control fluid circulating in the temperature control system 100 is referred to as the "first fluid" when it is controlled to a low temperature by the first chiller 110, and as the "second fluid" when it is controlled to a high temperature by the second chiller 120. However, these fluids only differ in temperature, and only one type of fluid circulates within the system.

[0054] The temperature control system 100 has pipes P1 to P14 to allow fluid to flow. The temperature control system 100 has various parts connected through the pipes P1 to P14, thereby forming a circulation path within the system. Each pipe P1 to P14 is also provided with valves v1 to v12 that function as gate valves to control whether or not each fluid can flow. The valves v1 to v12 are controlled to open and close by the control device 3, allowing the fluid to flow in the desired direction. Naturally, when the temperature control system 100 guides the flow direction of the fluid to reach the destination, it controls each valve to open only the necessary valves and close the other valves to prevent mixing with other fluids.

[0055] The first chiller 110 controls the first fluid, which serves as a heat medium, to a predetermined temperature. The first chiller 110 is connected to a temperature adjustment unit 151 of the fluid supply control unit 150 through a pipe P1. The first chiller 110 is connected to a flow direction switching unit 152 through a pipe P3. The pipe P3 can function as a flow path for returning the first fluid returning from the flow path 15 directly to the first chiller 110. In this embodiment, an insulating fluid such as Galden (registered trademark) that functions as a heat medium can be used as the first fluid, and a fluid that becomes liquid in the temperature range to be used is selected.

[0056] The first chiller 110 cools the first fluid to a target temperature of the temperature control base 14, which is set in the range of −100° C. to 0° C. The first chiller 110 can control the temperature of the first fluid to a temperature set in the range of up to −10° C. below the target temperature. The first fluid is supplied to the temperature control base 14, thereby lowering the temperature of the electrostatic chuck 13 to the desired target temperature.

[0057] The second chiller 120 controls the second fluid, which serves as a heat medium, to a temperature different from that of the first fluid. The second chiller 120 is connected to the temperature adjustment unit 151 of the fluid supply control unit 150 through a pipe P2. The second chiller 120 is connected to the flow direction switching unit 152 through a pipe P5. The pipe P5 can function as a flow path for returning the second fluid returning from the flow path 15 directly to the second chiller 120. In this embodiment, the second fluid is the same as the first fluid.

[0058] The second chiller 120 heats the second fluid to a target temperature of the temperature control base 14, which is set in the range of 40°C to 200°C. The second chiller 120 can control the temperature of the second fluid to a temperature set in the range of up to +10°C above the target temperature. When the second fluid is supplied to the temperature control base 14, it heats the electrostatic chuck 13 to the desired target temperature.

[0059] The storage unit 130 is a storage tank that includes a first storage unit 131 and a second storage unit 132 and is located upstream of the first chiller 110 and the second chiller 120 in the fluid flow direction. The storage unit 130 stores the return fluid from the temperature control base 14, adjusts the temperature to be equivalent to the control temperature of the first chiller 110 or the second chiller 122, and then returns the return fluid to the first chiller 110 or the second chiller 120. The storage unit 130 functions as a buffer element that prevents the temperature of the first fluid supplied from the first chiller 110 or the second fluid supplied from the second chiller 120 from changing from the control temperature.

[0060] The first storage unit 131 is disposed upstream of the first chiller 110. The first storage unit 131 is connected to the first chiller 110 through pipes P3 and P4. The first storage unit 131 circulates the first fluid between the first chiller 110 and the first storage unit 131, and can adjust the temperature of the stored fluid to the control temperature of the first chiller 110.

[0061] The first storage unit 131 is connected to the flow direction switching unit 152 through a pipe P8. The first storage unit 131 stores the first fluid supplied from the first chiller 110 as a return fluid returning from the temperature control base 14. Therefore, the return fluid stored in the first storage unit 131 is the first fluid.

[0062] The first storage unit 131 adjusts the temperature of the first fluid, which is the return fluid, so that it is equivalent to the control temperature of the first chiller 110. The first storage unit 131 returns the temperature-adjusted return fluid to the first chiller 110. The temperature of the return fluid in the first storage unit 131 is controlled by the first chiller 110. In this way, the first fluid returned from the first storage unit 131 has a temperature equivalent to that of the first fluid in the first chiller 110 when it returns to the first chiller 110. Therefore, the first chiller 110 can always supply the first fluid at a stable temperature.

[0063] When the temperature reaches the same temperature as the control temperature of the first chiller 110, the return fluid returning to the first storage unit 131 can be returned directly to the first chiller 110 through the pipe P3. In the temperature control system 100, the pipe P3 can function as a bypass path that does not pass through the second storage unit 132.

[0064] The second storage unit 132 is disposed upstream of the second chiller 120. The second storage unit 132 is connected to the second chiller 120 through pipes P5 and P6. The second storage unit 132 circulates the first fluid between the second storage unit 132 and the second chiller 120, and can adjust the temperature of the stored fluid to the control temperature of the second chiller 120.

[0065] The second storage unit 132 is connected to the flow direction switching unit 152 through a pipe P9. The second storage unit 132 stores the second fluid supplied from the second chiller 120 as a return fluid returning from the temperature control base 14. Therefore, the return fluid stored in the second storage unit 132 is the second fluid.

[0066] The second storage unit 132 adjusts the temperature of the second fluid, which is the return fluid, so that it is equivalent to the control temperature of the second chiller 120. The second storage unit 132 returns the temperature-adjusted return fluid to the second chiller 120. The temperature of the return fluid in the second storage unit 132 is controlled by the second chiller 120. In this way, the second fluid returned from the second storage unit 132 has a temperature equivalent to that of the second fluid in the second chiller 120 when it returns to the second chiller 120. Therefore, the second chiller 120 can always supply the second fluid at a stable temperature.

[0067] Note that the return fluid returning to the second storage unit 132 can also be returned directly to the second chiller 120 through the pipe P5 when the temperature of the return fluid reaches the same temperature as the control temperature of the second chiller 120. In the temperature control system 100, the pipe P5 can function as a bypass path that does not pass through the second storage unit 132.

[0068] For example, when rapidly heating the temperature control base 14, which is in a low temperature state, the second chiller 120 supplies the temperature control base 14 with a second fluid heated to a target temperature. Because the temperature control base 14 is in a low temperature state, the temperature of the supplied second fluid is cooled after passing through the flow path 15. If this cooled second fluid were returned directly to the second chiller 120, it would lower the temperature of the second fluid in the second chiller 120, making it impossible to keep up with temperature adjustment. As a result, the second chiller 120 would supply the second fluid at a temperature that deviates from the target temperature, and it would take a long time to reach the target temperature. To avoid this problem, the temperature control system 100 of this embodiment temporarily stores the return fluid from the temperature control base 14 in the second storage unit 132, adjusts the temperature to a temperature equivalent to the control temperature of the second chiller 120, and then returns it to the second chiller 120 as the second fluid. Therefore, the second chiller 120 can constantly supply the second fluid adjusted to the target temperature, and the temperature control time is not affected.

[0069] The fluid discharge unit 140 includes a gas supply unit 141 and a discharge fluid storage unit 142 .

[0070] The gas supply unit 141 supplies an inert compressed gas to be used as the exhaust gas to the flow path 15 of the temperature control base 14. The gas supply unit 141 is connected to the fluid supply control unit 150 through a pipe P10. By supplying the exhaust gas to the flow path 15, the gas supply unit 141 can quickly exhaust the fluid in the flow path 15 to the outside of the flow path 15 when raising or lowering the target temperature of the temperature control base 14.

[0071] The discharged fluid storage unit 142 stores the return fluid discharged to outside the flow path 15 by the gas supply unit 141. The discharged fluid storage unit 142 is connected to the flow direction switching unit 152 through a pipe P11. The discharged fluid storage unit 142 is connected to the first chiller 110 through a pipe P12 and to the second chiller 120 through a pipe P13.

[0072] The discharged fluid storage unit 142 is open to the atmosphere, and the discharged exhaust gas escapes to the atmosphere, while the return fluid and the atmosphere are stored. The return fluid stored in the discharged fluid storage unit 142 is returned to the corresponding chiller (first chiller 110 or second chiller 120) depending on the fluid temperature.

[0073] The fluid supply control unit 150 has a temperature adjustment unit 151 and a flow direction switching unit 152. The fluid supply control unit 150 selectively causes the first fluid from the first chiller 110 and the second fluid from the second chiller 120 to flow through the temperature control base 14.

[0074] The temperature adjustment unit 151 is connected to the flow direction switching unit 152 through a pipe P14. The flow direction switching unit 152 is connected to the pipes 16a and 16b.

[0075] The temperature adjustment unit 151 cools the first fluid to a temperature lower than a target temperature, and heats the second fluid to a temperature higher than the target temperature. The temperature adjustment unit 151 increases the temperature by 10°C or more above the target temperature when increasing the temperature, and decreases the temperature by -10°C or more below the target temperature when decreasing the temperature. The temperature adjustment unit 151 adjusts the temperature of the fluid to be temperature-adjusted by feedback control.

[0076] For example, when increasing the temperature, if the temperature control base 14 continues to supply the second fluid adjusted by the second chiller 120 to a temperature higher than the target temperature in order to shorten the time, an overshoot occurs. After the overshoot occurs, even if the control temperature of the second chiller 120 is controlled to the target temperature, it takes a long time to stabilize at the target temperature. In contrast, the temperature adjustment unit 151 of this embodiment controls the temperature of the second fluid to be higher than the target temperature in order to shorten the temperature increase time, but controls the heating of the second fluid to an appropriate temperature by feedback control to prevent overshoot. Therefore, the temperature control base 14 is quickly controlled to the target temperature without overshooting. Furthermore, the temperature adjustment unit 151 can further shorten the temperature control time by adjusting the temperature of the fluid circulating during temperature increase or decrease to be higher (or lower) than the target temperature.

[0077] The flow direction switching unit 152 controls the flow direction of the fluid circulating in the temperature control base 14 in accordance with the fluid temperature. The flow direction switching unit 152 is connected to the first storage unit 131 through piping P8. The flow direction switching unit 152 is connected to the second storage unit 132 through piping P9. The flow direction switching unit 152 is connected to the discharge fluid storage unit 142 through piping P11. The flow direction switching unit 152 is connected to the first chiller 110 through piping P3. The flow direction switching unit 152 is connected to the second chiller 120 through piping P5.

[0078] The flow direction switching unit 152 causes the first fluid supplied from the first chiller 110 to flow along a second direction from the outer periphery toward the center of the temperature control base 14. The flow direction switching unit 152 causes the second fluid supplied from the second chiller 120 to flow along the first direction from the center toward the outer periphery of the temperature control base 14. Furthermore, the flow direction switching unit 152 can cause the exhaust gas supplied from the gas supply unit 141 to flow in either the first direction or the second direction.

[0079] Conventional plasma processing apparatuses have a problem in that, for example, when a low-temperature fluid of −50° C. or less is used to increase the etching rate and a high-temperature fluid of 50° C. or higher is used to increase the removal efficiency of deposit removal, the sudden temperature change causes temperature unevenness and damages the electrostatic chuck. To solve this problem, the present inventors conducted extensive research, focusing on the characteristics of ceramics, which are the material forming the electrostatic chuck 13, as described below. As a result, the present inventors discovered that by appropriately controlling the flow direction of the fluid flowing through the temperature control base 14, damages to the electrostatic chuck 13 can be prevented even when switching fluids with a temperature difference of 100° C. or more, which led to the development of the present invention.

[0080] In this embodiment, the electrostatic chuck 13, whose temperature is controlled by the first and second fluids, may be made of ceramics such as Al2O3. Ceramics tend to have extremely low tensile strength relative to their compressive strength. For example, during low-temperature maintenance operation, the temperature control base 14 is configured to be in contact with and fixed to the lower housing 2b on its outer periphery. Because the temperature of the temperature control base 14 tends to increase on the outer periphery due to heat conduction from the lower electrode 12 and the vacuum chamber 10, the low-temperature first fluid is circulated in the second direction. When switching to the next temperature-raising operation, if the high-temperature second fluid is circulated in the second direction, the electrostatic chuck 13 expands toward the outer periphery due to the high temperature of the outer periphery. However, because the inner periphery is cooler than the outer periphery and expands less than the outer periphery, tensile stress is generated within the component. This increases the likelihood of the electrostatic chuck 13 being damaged by thermal stress. In contrast, the temperature control system 100 of this embodiment circulates a low-temperature first fluid in a second direction and a high-temperature second fluid in a first direction opposite to the first fluid. As a result, the outer periphery of the electrostatic chuck 13 is lower in temperature than the inner periphery and expands less, while the inner periphery expands relative to the outer periphery, generating compressive stress inside the part. As described above, the ceramic electrostatic chuck 13 has excellent compressive strength, so damage due to thermal stress can be prevented. Furthermore, the electrostatic chuck 13 has less uneven temperature distribution than a case in which each fluid flows in the same direction.

[0081] As described above, the temperature control system 100 controls the flow direction of the fluid in consideration of the material properties of the electrostatic chuck 13. Therefore, the temperature control system 100 can perform appropriate temperature control while preventing damage to the electrostatic chuck 13, even in a situation where a sudden temperature change occurs, such as when switching from a low-temperature maintenance operation to a temperature increase operation.

[0082] Next, the operation of the temperature control system 100 will be described with reference to Figures 4A to 4D. Below, the flow of fluid in four operations, "low temperature maintenance operation," "temperature increase operation," "high temperature maintenance operation," and "temperature decrease operation," will be described. As a basic operation, the temperature control system 100 performs temperature control in the order of low temperature maintenance operation → temperature increase operation → high temperature maintenance operation → temperature decrease operation.

[0083] The low temperature maintenance operation will be described with reference to Fig. 4A. The low temperature maintenance operation is an operation for maintaining a target temperature set within the range of -100°C to 0°C. In the low temperature maintenance operation, valves v1, v5, and v8 are opened as appropriate to control the flow of fluid.

[0084] In the low-temperature maintenance operation, the temperature control system 100 controls the temperature of the first fluid to the target temperature using the first chiller 110. Next, the temperature control system 100 opens valve v1 to supply the first fluid from the first chiller 110 to the flow direction switching unit 152. Because the temperature control base 14 has already reached the target temperature, the temperature adjustment unit 151 controls the temperature of the first fluid only when necessary.

[0085] The flow direction switching unit 152 causes the first fluid to flow along the second direction through the flow path 15 of the temperature control base 14. As a result, the first fluid flows from the outer periphery of the flow path 15 toward the center.

[0086] The first fluid that has passed through the flow path 15 is returned to the first chiller 110 by opening the valve v5. In preparation for the next temperature increase operation, the return fluid stored in the second storage unit 132 is circulated between the first chiller 110 and the second chiller 120 by opening the valve v8, and is adjusted to the control temperature of the second chiller 120.

[0087] As described above, the low temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled first fluid.

[0088] Next, the temperature increase operation will be described with reference to Fig. 4B. The temperature increase operation is an operation for increasing the temperature from, for example, a low target temperature before the temperature increase to a high target temperature after the temperature increase. In the temperature increase operation, valves v2, v4, v6 to v10, and v11 are appropriately opened to control the flow of fluid.

[0089] During the temperature increase operation, the temperature control system 100 closes the valve v1 to stop the supply of the first fluid from the first chiller 110. During the low-temperature maintenance operation, the fluid stored in the second storage unit 132 is circulated between the second storage unit 132 and the second chiller 120 and adjusted to the control temperature of the second chiller 120. Note that the fluid in the second storage unit 132 may continue to be circulated during the temperature increase operation until it is adjusted to the control temperature of the second chiller 120.

[0090] Next, the temperature control system 100 opens the valve v9 to supply exhaust gas from the gas supply unit 141 to the flow path 15 of the temperature control base 14. The first fluid remaining inside the flow path 15 to which the exhaust gas has been supplied is pushed out by the supplied exhaust gas. The first fluid discharged from the flow path 15 returns to the exhaust fluid storage unit 142 as a return fluid by opening the valve v10. The fluid returned to the exhaust fluid storage unit 142 is returned to the first chiller 110 by opening the valve v11.

[0091] Next, the second chiller 120 opens the valve v2 to supply the second fluid, the temperature of which has been controlled to the target temperature, to the temperature adjustment unit 151. The temperature adjustment unit 151 controls the temperature of the second fluid that has flowed in using feedback control, and supplies the second fluid to the flow direction switching unit 152 through the pipe P14.

[0092] The flow direction switching portion 152 causes the second fluid to flow along the first direction of the flow channel 15. As a result, the second fluid flows from the center side of the flow channel 15 toward the outer periphery side.

[0093] The second fluid that has passed through flow path 15 is returned to second storage unit 132 by opening valve v4. Second storage unit 132 adjusts the temperature of the second fluid, which is the return fluid, to the same temperature as the control temperature of second chiller 120, and then returns it to second chiller 120. When the temperature of the return fluid becomes the same as the control temperature of second chiller 120, valve v6 is opened, the flow direction of the return fluid is switched to pipe P5, which serves as a bypass route, and the return fluid is returned directly to second chiller 120. In preparation for the next temperature-lowering operation, valve v7 is opened, and the fluid stored in first storage unit 131 is circulated between first chiller 110 and adjusted to the control temperature of the first chiller 110.

[0094] As described above, the temperature raising operation is performed at an appropriate timing, thereby raising the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled second fluid.

[0095] Next, the high temperature maintenance operation will be described with reference to Fig. 4C. The high temperature maintenance operation is an operation for maintaining a target temperature set within the range of 40°C to 200°C. In the high temperature maintenance operation, valves v2, v6, and v7 are opened as appropriate to control the flow of fluid.

[0096] In the high temperature maintenance operation, the temperature control system 100 controls the temperature of the second fluid to the target temperature using the second chiller 120. Next, the temperature control system 100 opens valve v2 to the flow direction switching unit 152 to supply the second fluid from the second chiller 120. Because the temperature control base 14 has already reached the target temperature, the temperature adjustment unit 151 controls the temperature of the second fluid only when necessary.

[0097] The flow direction switching unit 152 causes the second fluid to flow along the first direction through the flow path 15 of the temperature control base 14. As a result, the second fluid flows from the center side of the flow path 15 toward the outer periphery side.

[0098] The second fluid that has passed through flow path 15 is returned to second chiller 120 by opening valve v6. In preparation for the next temperature-lowering operation, valve v7 is opened for the fluid stored in first storage unit 131, and the fluid is circulated between first chiller 110 and adjusted to the control temperature of first chiller 110.

[0099] As described above, the high temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled second fluid.

[0100] The temperature-lowering operation will be described with reference to Fig. 4D. The temperature-lowering operation is an operation for lowering the temperature, for example, from a high target temperature before the temperature-lowering operation to a low target temperature after the temperature-lowering operation. The temperature-lowering operation controls the flow of fluid by appropriately opening valves v1, v3, v5, v7 to v10, and v12.

[0101] In the temperature-lowering operation, the temperature control system 100 closes the valve v2 to stop the supply of the second fluid from the second chiller 120. The fluid stored in the first storage unit 131 is circulated between the first chiller 110 and the first chiller 110 during the high-temperature maintenance operation, and is adjusted to the control temperature of the first chiller 110. Note that the fluid in the first storage unit 131 may continue to be circulated during the temperature-lowering operation until it is adjusted to the control temperature of the first chiller 110.

[0102] Next, the temperature control system 100 opens the valve v9 to supply exhaust gas from the gas supply unit 141 to the flow path 15 of the temperature control base 14. The first fluid remaining inside the flow path 15 is pushed out by the exhaust gas supplied thereto. The second fluid discharged from the flow path 15 returns to the exhaust fluid storage unit 142 as a return fluid by opening the valve v10. The fluid returned to the exhaust fluid storage unit 142 is returned to the second chiller 120 by opening the valve v12.

[0103] Next, the first chiller 110 opens the valve v1 to supply the first fluid, the temperature of which has been controlled to the target temperature, to the temperature adjustment unit 151. The temperature adjustment unit 151 controls the temperature of the first fluid that has flowed in using feedback control, and supplies the first fluid to the flow direction switching unit 152 through the pipe P14.

[0104] The flow direction switching portion 152 causes the second fluid to flow along the second direction of the flow channel 15. As a result, the second fluid flows from the outer periphery side of the flow channel 15 toward the center side.

[0105] The first fluid that has passed through flow path 15 is returned to the first storage unit 131 by opening valve v3. The first storage unit 131 adjusts the temperature of the return fluid to the same temperature as the control temperature of the first chiller 110, and then returns the return fluid to the first chiller 110. When the temperature of the return fluid becomes the same as the control temperature of the first chiller 110, valve v5 is opened, the flow direction of the return fluid is switched to pipe P3, which serves as a bypass route, and the return fluid is returned directly to the first chiller 110. In preparation for the next heating operation, valve v8 is opened, and the fluid stored in the second storage unit 132 is circulated between the second storage unit 132 and the second chiller 120, and adjusted to the control temperature of the second chiller 120.

[0106] As described above, the temperature lowering operation is performed at an appropriate timing, thereby lowering the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled first fluid.

[0107] Next, a temperature control system 100A according to a second embodiment of the present invention will be described. In the temperature control system 100A according to the second embodiment, the same components as those in the other embodiments described above will be assigned the same reference numerals, and their description will be omitted. Furthermore, the components not specifically mentioned can be configured in the same way as the above-described embodiments.

[0108] A temperature control system 100A according to a second embodiment of the present invention will be described below. Fig. 5 shows a block diagram of the temperature control system 100A according to the second embodiment.

[0109] As shown in FIG. 5, the temperature control system 100A differs from the above-described embodiments in that it includes a common storage unit 160 instead of the first storage unit 131 and the second storage unit 132.

[0110] The common storage unit 160 serves to store fluid that has passed through the flow paths 15 during temperature increase or decrease and has a temperature different from the control temperature of the first chiller 110 or the second chiller 120, and to return fluid close to the control temperature to the first chiller 110 or the second chiller 120. During temperature decrease operations, the common storage unit 160 supplies the return fluid, controlled to the control temperature of the first chiller 110, to the first chiller 110 as the first fluid. During temperature increase operations, the common storage unit 160 supplies the return fluid, controlled to the control temperature of the second chiller 120, to the second chiller 120 as the second fluid. The common storage unit 160 functions as a buffer element to prevent the first fluid supplied from the first chiller 110 or the second fluid supplied from the second chiller 120 from changing from the control temperature due to fluid that has passed through the flow paths 15 and has a temperature different from the control temperature.

[0111] The common storage unit 160 is connected to the first chiller 110 through pipes P17 and P18, and can circulate a fluid. The common storage unit 160 is connected to the second chiller 120 through pipes P19 and P20, and can circulate a fluid. The common storage unit 160 is connected to the flow direction switching unit 152 through pipes P15, in which a valve v13 is disposed, and P16, in which a valve v14 is disposed, and receives the return fluid from the temperature control base 14.

[0112] When maintaining a high temperature, the common storage unit 160 circulates the return fluid stored between the first chiller 110 through a pipe P17 in which a valve v15 is disposed and a pipe P18 in which a valve v16 is disposed so that the return fluid is at the control temperature of the first chiller 110. When maintaining a low temperature, the common storage unit 160 circulates the return fluid stored between the second chiller 120 through a pipe P19 in which a valve v17 is disposed and a pipe P20 in which a valve v18 is disposed so that the return fluid is at the control temperature of the second chiller 120. In this way, the common storage unit 160 can adjust the stored fluid to the control temperature of the first chiller 110 or the second chiller 120 in preparation for the next heating operation or cooling operation.

[0113] The common storage unit 160 may be configured to be capable of storing the first fluid and the second fluid, and may be configured with a storage tank or a chiller having a temperature control function.

[0114] The temperature adjustment unit 151 raises or lowers the temperature of the fluid from the first chiller 110 and the second chiller 120 to a temperature higher or lower than the target temperature while performing feedback control. As a result, the temperature control base 14 circulates the first fluid or the second fluid whose temperature is higher or lower than the target temperature, thereby shortening the time required for temperature control to reach the target temperature.

[0115] As described above, when switching between fluids of different temperatures during temperature rise and fall, the temperature control system 100A controls the return fluid to a target temperature in advance in the common reservoir 160 to ensure that the temperature of the return fluid to the first chiller 110 or the second chiller 120 is as close to the chiller control temperature as possible. This reduces temperature fluctuations caused by the return fluid of the first or second fluid during temperature rise and fall, enabling faster and more efficient temperature control. Furthermore, the temperature control system 100A temporarily stores the return fluid from the temperature control base 14 in the common reservoir 160, adjusts it to the same temperature as the control temperature of the first chiller 110 or the second chiller 120, and then returns it to the corresponding chiller. This reduces temperature changes in the first fluid in the first chiller 110 and the second fluid in the second chiller 120.

[0116] 5, the temperature control system 100A described above is configured without the fluid discharge unit 140, but the fluid discharge unit 140 may be incorporated into the system. In this case, the fluid discharge unit 140 can quickly discharge the fluid in the flow path 15 when performing a temperature increase or decrease operation.

[0117] Next, the operation of the temperature control system 100A will be described with reference to Figures 6A to 6D. Below, the flow of fluid in four operations, "low temperature maintenance operation," "temperature increase operation," "high temperature maintenance operation," and "temperature decrease operation," will be described. As a basic operation, the temperature control system 100A performs temperature control in the order of low temperature maintenance operation → temperature increase operation → high temperature maintenance operation → temperature decrease operation.

[0118] The low temperature maintenance operation will be described with reference to Fig. 6A. In the low temperature maintenance operation, the valves v1, v5, v17, and v18 are appropriately opened to control the flow of fluid.

[0119] In the low-temperature maintenance operation, the temperature control system 100A controls the temperature of the first fluid to a target temperature in the first chiller 110. Next, the temperature control system 100A opens the valve v1 in the flow direction switching unit 152 to supply the first fluid from the first chiller 110.

[0120] The flow direction switching unit 152 causes the first fluid to flow along the second direction through the flow path 15 of the temperature control base 14. As a result, the first fluid flows from the outer periphery of the flow path 15 toward the center.

[0121] The first fluid that has passed through flow path 15 is returned to the first chiller 110 by opening valve v5. In preparation for the next temperature increase operation, valves v17 and v18 are opened to circulate the fluid stored in the common reservoir 160 between the common reservoir 160 and the second chiller 120, and the fluid is adjusted to the control temperature of the second chiller 120.

[0122] As described above, the low temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled first fluid.

[0123] The temperature increasing operation will be described with reference to Fig. 6B. In the temperature increasing operation, the valves v2, v6, v14, and v18 are opened appropriately to control the flow of fluid.

[0124] In the temperature increasing operation, the temperature control system 100A closes the valve v1 to stop the supply of the first fluid from the first chiller 110.

[0125] Next, the temperature control system 100A opens the valve v2 to supply the second fluid from the second chiller 120 to the temperature adjustment unit 151. The temperature adjustment unit 151 performs feedback control to further raise the temperature of the second fluid that has flowed in above the target temperature, and supplies the second fluid to the flow direction switching unit 152 through the pipe P14.

[0126] The flow direction switching portion 152 causes the second fluid to flow along the first direction of the flow channel 15. As a result, the second fluid flows from the center side of the flow channel 15 toward the outer periphery side.

[0127] The second fluid that has passed through the flow path 15 returns to the common reservoir 160 when the valve v14 is opened. The temperature control system 100A supplies the fluid stored in the common reservoir 160 to the second chiller 120 until the temperature of the second fluid approaches the temperature of the common reservoir 160.

[0128] When the temperature of the second fluid returning to the common reservoir 160 approaches the control temperature of the second chiller 120, the temperature control system 100A stops the supply of fluid from the common reservoir 160. Valve v6 is opened, and the flow direction of the returning fluid is switched to pipe P7, which serves as a bypass route, and the returning fluid returns directly to the second chiller 120.

[0129] As described above, the temperature raising operation is performed at an appropriate timing, thereby raising the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled second fluid.

[0130] The high temperature maintenance operation will be described with reference to Fig. 6C. In the high temperature maintenance operation, the valves v2, v6, v15, and v16 are opened as appropriate to control the flow of fluid.

[0131] In the high temperature maintenance operation, the temperature control system 100A controls the temperature of the second fluid to the target temperature using the second chiller 120. Next, the temperature control system 100A opens valve v2 to the flow direction switching unit 152 to supply the second fluid from the second chiller 120. Because the temperature control base 14 has already reached the target temperature, the temperature adjustment unit 151 controls the temperature of the second fluid only when necessary.

[0132] The flow direction switching unit 152 causes the second fluid to flow along the first direction through the flow path 15 of the temperature control base 14. As a result, the second fluid flows from the center side of the flow path 15 toward the outer periphery side.

[0133] The second fluid that has passed through flow path 15 returns to second chiller 120 when valve v6 is opened. In addition, the fluid stored in common reservoir 160 is circulated between first chiller 110 and the common reservoir 160, and adjusted to the control temperature of first chiller 110 in preparation for the next temperature reduction operation.

[0134] As described above, the high temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled second fluid.

[0135] The temperature lowering operation will be described with reference to Fig. 6D. In the temperature lowering operation, the valves v1, v5, v13, and v15 are opened as appropriate to control the flow of fluid.

[0136] In the temperature decreasing operation, the temperature control system 100A closes the valve v2 to stop the supply of the second fluid from the second chiller 120.

[0137] Next, the temperature control system 100A opens the valve v1 to supply the first fluid from the first chiller 110 to the temperature adjustment unit 151. The temperature adjustment unit 151 cools the first fluid that has flowed in to a temperature lower than the target temperature, and supplies the first fluid to the flow direction switching unit 152 through the pipe P14.

[0138] The flow direction switching portion 152 causes the first fluid to flow along the second direction of the flow channel 15. As a result, the first fluid flows from the outer periphery side of the flow channel 15 toward the center side.

[0139] The first fluid that has passed through the flow path 15 returns to the common reservoir 160 when the valve v13 is opened. The temperature control system 100A supplies the fluid stored in the common reservoir 160 to the first chiller 110 until the temperature of the first fluid approaches the temperature of the common reservoir 160.

[0140] When the temperature of the first fluid returning to the common reservoir 160 approaches the control temperature of the first chiller 110, the temperature control system 100A stops the supply of fluid from the common reservoir 160. Valve v5 is opened, and the flow direction of the returning fluid is switched to pipe P7, which serves as a bypass route, and the returning fluid returns directly to the first chiller 110.

[0141] As described above, the temperature lowering operation is performed at an appropriate timing, thereby lowering the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled first fluid.

[0142] Next, a temperature control system 100B according to a third embodiment of the present invention will be described. In the temperature control system 100B according to the third embodiment, the same components as those in the other embodiments described above will be assigned the same reference numerals, and their description will be omitted. Furthermore, the components not specifically mentioned can be configured in the same way as the above-described embodiments.

[0143] A temperature control system 100B according to a second embodiment of the present invention will now be described. Fig. 7 shows a block diagram of a temperature control system 100B according to a third embodiment.

[0144] As shown in Figure 7, temperature control system 100B differs from the above-described embodiments in that it includes a high temperature maintenance storage unit 170. For ease of explanation, the temperature control fluids circulating in temperature control system 100B are referred to as the "first fluid" for the fluid controlled to a low temperature by first chiller 110, the "second fluid" for the fluid controlled to a high temperature by second chiller 120, and the "third fluid" for the fluid supplied from high temperature maintenance storage unit 170. However, these fluids only differ in temperature, and only one type of fluid circulates within the system.

[0145] As shown in Fig. 7, the temperature control system 100B has a high temperature maintenance storage unit 170 and a temperature increase / decrease control unit 180. Furthermore, as shown in Fig. 7, the temperature control system 100B can have the high temperature maintenance storage unit 170 disposed between the temperature control base 14 and the flow direction switching unit 152. Although not illustrated, the high temperature maintenance storage unit 170 may also be disposed downstream of the flow direction switching unit 152. The temperature control base 14 and the flow direction switching unit 152 are connected by pipes P21 and P22. A valve v19 is disposed in the pipe P21. A valve v20 is disposed downstream of the fluid flow port 171b of the high temperature maintenance storage unit 170.

[0146] The high temperature maintenance storage unit 170 has fluid circulation ports 171a and 171b arranged between the temperature control base 14 and the temperature rise / fall control unit 180, and supplies a third fluid adjusted to a temperature higher than the target temperature (+10°C or higher) from the fluid circulation port 171a. The fluid circulation port 171a is connected to the pipe P1 or the pipe 16a. The fluid circulation port 171b is connected to the pipe P1 or the pipe P21. The third fluid flows from the center side of the flow path 15 toward the outer periphery.

[0147] Furthermore, in order to improve temperature rise responsiveness, it is desirable to place the high temperature maintenance storage unit 170 near (within 1 meter of) the temperature control base 14. This prevents the temperature of the third fluid supplied from the high temperature maintenance storage unit 170 from decreasing during circulation, and allows the third fluid to be supplied to the temperature control base 14 while maintaining a high temperature. As a result, the temperature control system 100B can shorten the temperature control time.

[0148] During the temperature raising operation, the high temperature maintenance storage unit 170 may stop supplying the third fluid when the supply of the third fluid corresponding to the storage capacity is completed or when a predetermined amount of the third fluid has been supplied. When the supply of the third fluid from the high temperature maintenance storage unit 170 is stopped, the second chiller 120 starts supplying the second fluid.

[0149] The temperature rise / fall control unit 180 includes a first chiller 110, a second chiller 120, a storage unit 130, and a fluid discharge unit 140. The temperature rise / fall control unit 180 is located upstream of the temperature control base 14, and supplies fluid controlled to a predetermined temperature to the temperature control base 14 to control the temperature.

[0150] 7, the temperature control system 100B does not include the temperature adjustment unit 151, but the temperature adjustment unit 151 may be incorporated into the system. In this case, the temperature adjustment unit 151 can raise or lower the temperatures of the first fluid, second fluid, and third fluid to desired temperatures during temperature raising or lowering operations. Furthermore, the temperature control system 100B may be configured to include a separate common reservoir 160 to store the return fluid from the temperature control base 14, as in the temperature control system 100A of the first embodiment.

[0151] Next, the operation of the temperature control system 100B will be described with reference to Figures 8A to 8D. Below, the flow of fluid in four operations, "low temperature maintenance operation," "temperature increase operation," "high temperature maintenance operation," and "temperature decrease operation," will be described. Here, the explanation will be based on the system configuration shown in Figure 7B. As a basic operation, the temperature control system 100B performs temperature control in the order of low temperature maintenance operation → temperature increase operation → high temperature maintenance operation → temperature decrease operation.

[0152] The low temperature maintenance operation will be described with reference to Fig. 8A. In the low temperature maintenance operation, the valves v1, v5, v8, and v19 are appropriately opened to control the flow of fluid.

[0153] In the low-temperature maintenance operation, the temperature control system 100B controls the temperature of the first fluid to a target temperature in the first chiller 110. Next, the temperature control system 100B opens the valve v1 in the flow direction switching unit 152 to supply the first fluid from the first chiller 110.

[0154] The flow direction switching unit 152 causes the first fluid to flow in the second direction through the pipe P22 to the flow path 15 of the temperature control base 14. As a result, the first fluid flows from the outer periphery of the flow path 15 toward the center.

[0155] After passing through flow path 15, valve v19 is opened and the first fluid passes through pipe P21 and flow direction switching unit 152, and then valve v5 is opened to return to first chiller 110. Note that, in preparation for the next temperature increase operation, valve v8 is opened and the fluid stored in second storage unit 132 is circulated between second chiller 120 and adjusted to the control temperature of second chiller 120.

[0156] As described above, the low temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled first fluid.

[0157] The temperature raising operation will be described with reference to Fig. 8B. In the temperature raising operation, the valves v2, v4, v6 to v11, v19, and v20 are opened as appropriate to control the flow of fluid.

[0158] During the temperature increase operation, the temperature control system 100B closes the valve v1 to stop the supply of the first fluid from the first chiller 110. During the low-temperature maintenance operation, the fluid stored in the second storage unit 132 is circulated between the second storage unit 132 and the second chiller 120 and adjusted to the control temperature of the second chiller 120. Note that the fluid in the second storage unit 132 may continue to be circulated during the temperature increase operation until it is adjusted to the control temperature of the second chiller 120.

[0159] Next, the temperature control system 100B opens the valves v9 and v19 to the flow path 15 of the temperature control base 14, and supplies exhaust gas from the gas supply unit 141. The first fluid remaining inside the flow path 15 to which the exhaust gas has been supplied is pushed out by the supplied exhaust gas. The first fluid discharged from the flow path 15 passes through the pipe P22 and the flow direction switching unit 152, and then returns to the exhaust fluid storage unit 142 as a return fluid by opening the valve v10. The fluid returned to the exhaust fluid storage unit 142 is returned to the first chiller 110 by opening the valve v11.

[0160] Next, the high temperature maintenance storage unit 170 supplies the third fluid, whose temperature has been controlled to a temperature higher than the target temperature, to the temperature control base 14 through the fluid flow port 171a by closing valve v19 and opening valve v20. The third fluid flows through the second fluid along the first direction of the flow path 15. As a result, the second fluid flows from the center of the flow path 15 toward the outer periphery. The method of flowing the third fluid through the high temperature maintenance storage unit 170 may include an active supply function, or a passive function in which the third fluid is pushed out by the second fluid in a sealed container. Valves v19 and v20 may be opened and closed as appropriate depending on their functions.

[0161] Next, when the supply from the high temperature maintenance storage unit 170 stops, the temperature control system 100B opens the valve v2 and supplies the second fluid from the second chiller 120 to the flow direction switching unit 152, controlling the temperature to the target temperature. When the valve v19 is opened, the flow direction switching unit 152 causes the second fluid to flow along the first direction of the flow path 15. As a result, the second fluid flows from the center side of the flow path 15 toward the outer periphery.

[0162] The second fluid that has passed through flow path 15 passes through pipe P22 and flow direction switching unit 152, and then returns to second storage unit 132 by opening valve v4. Second storage unit 132 adjusts the temperature of the second fluid, which is the return fluid, to the same temperature as the control temperature of second chiller 120, and then returns it to the second chiller 120. When the temperature of the return fluid becomes the same as the control temperature of second chiller 120, valve v6 is opened, and the flow direction of the return fluid is switched to pipe P5, which serves as a bypass route, and the return fluid returns directly to the second chiller 120. During the temperature increase operation, valve v7 is opened to prepare for the next temperature decrease operation, and the fluid stored in first storage unit 131 is circulated between first storage unit 131 and first chiller 110, and adjusted to the control temperature of the first chiller 110.

[0163] As described above, the temperature raising operation is performed at an appropriate timing, thereby raising the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled second fluid.

[0164] The high temperature maintenance operation will be described with reference to Fig. 8C. In the high temperature maintenance operation, the valves v2, v6, v7, and v19 are opened appropriately to control the flow of fluid.

[0165] In the high temperature maintenance operation, the temperature control system 100B controls the temperature of the second fluid to the target temperature in the second chiller 120. Next, the temperature control system 100B opens the valve v2 in the flow direction switching unit 152 to supply the second fluid from the second chiller 120.

[0166] The flow direction switching unit 152 opens the valve v19 to allow the second fluid to flow along the first direction in the flow path 15 of the temperature control base 14. As a result, the second fluid flows from the center side of the flow path 15 toward the outer periphery.

[0167] The second fluid that has passed through flow path 15 passes through pipe P22 and flow direction switching unit 152, and then returns to second chiller 120 by opening valve v6. During high-temperature maintenance operation, valve v7 is opened to prepare for the next temperature-lowering operation, and the fluid stored in first storage unit 131 is circulated between first chiller 110 and adjusted to the control temperature of first chiller 110.

[0168] As described above, the high temperature maintaining operation is performed at an appropriate timing to maintain the temperature control base 14 at the target temperature while circulating the temperature-controlled second fluid.

[0169] The temperature lowering operation will be described with reference to Fig. 8D. In the temperature lowering operation, the valves v1, v3, v5, v8, v9, v10, v12, and v19 are opened appropriately to control the flow of fluid.

[0170] In the temperature-lowering operation, the temperature control system 100B closes the valve v2 to stop the supply of the second fluid from the second chiller 120. During the high-temperature maintenance operation, the fluid stored in the first storage unit 131 is circulated between the first chiller 110 and the first chiller 110, and adjusted to the control temperature of the first chiller 110. Note that the fluid in the first storage unit 131 may continue to be circulated during the temperature-lowering operation until it is adjusted to the control temperature of the first chiller 110.

[0171] Next, the temperature control system 100B opens the valve v9 to supply exhaust gas from the gas supply unit 141 to the flow path 15 of the temperature control base 14. The second fluid remaining inside the flow path 15 is pushed out by the exhaust gas. The second fluid discharged from the flow path 15 returns to the exhaust fluid storage unit 142 as a return fluid by opening the valve v10. The fluid returned to the exhaust fluid storage unit 142 is returned to the second chiller 120 by opening the valve v12.

[0172] Next, the temperature control system 100B opens the valve v1 and supplies the first fluid from the first chiller 110 to the flow direction switching unit 152, controlling the temperature to the target temperature. The flow direction switching unit 152 causes the first fluid to flow through the pipe P22 in the second direction of the flow path 15. As a result, the first fluid flows from the outer periphery of the flow path 15 toward the center.

[0173] The first fluid that has passed through flow path 15 is returned to the first storage unit 131 by opening valve v3. The first storage unit 131 adjusts the temperature of the return fluid to the same temperature as the control temperature of the first chiller 110, and then returns the return fluid to the first chiller 110. When the temperature of the return fluid becomes the same as the control temperature of the first chiller 110, valve v5 is opened, the flow direction of the return fluid is switched to pipe P3, which serves as a bypass route, and the return fluid returns directly to the first chiller 110. During the temperature drop operation, valve v8 is opened to prepare for the next temperature increase operation, and the fluid stored in the second storage unit 132 is circulated between the second storage unit 132 and the second chiller 120, and adjusted to the control temperature of the second chiller 120.

[0174] As described above, the temperature lowering operation is performed at an appropriate timing, thereby lowering the temperature of the temperature control base 14 to the target temperature while circulating the temperature-controlled first fluid.

[0175] As described above, the temperature control system 100 of this embodiment is connectable to a plasma processing apparatus 1 capable of performing plasma etching processing on a workpiece W within a vacuum chamber 10, and includes a holding plate (electrostatic chuck 13) that holds the workpiece W placed on a mounting surface, a temperature control base 14 that is joined to the holding plate and has a flow path 15 formed therein through which a fluid can flow so that the holding plate reaches a target temperature, a lower housing 2b for holding the temperature control base 14 within the vacuum chamber 10, a first chiller 110 that supplies a first fluid controlled to a predetermined temperature, a second chiller 120 that supplies a second fluid controlled to a temperature different from the temperature controlled by the first chiller 110, and a fluid supply control unit 150 that selectively circulates at least the first fluid from the first chiller 110 and the second fluid from the second chiller 120 to the temperature control base 14. The fluid supply control unit 150 has a temperature adjustment unit 151 for heating or cooling the first fluid or the second fluid introduced into the temperature control base 14 to a target temperature, and a flow direction switching unit 152 for controlling the flow direction of each fluid. The flow direction switching unit 152 causes the second fluid to flow in a first direction from the center to the outer periphery of the temperature control base 14 when the temperature is rising, and causes the first fluid to flow in a second direction from the outer periphery to the center of the temperature control base 14 when the temperature is falling.

[0176] With this configuration, the temperature control system 100 can suppress uneven temperature distribution in the holding plate (electrostatic chuck 13) during temperature rise, even if a fluid with a temperature difference of 100°C or more is circulated, for example, when transitioning from a cryogenic environment to a deposit removal process, thereby preventing damage due to thermal stress caused by temperature changes. Furthermore, the temperature control system 100 can adjust the temperatures of the first fluid and the second fluid circulated through the flow path 15 to a temperature higher (or lower) than a target temperature using the temperature adjustment unit 151. Therefore, the temperature control system 100 can shorten the time required for temperature control to reach a desired target temperature. [Example]

[0177] The effects of the present invention will be explained using the following examples and comparative examples, although the technical scope of the present invention is not limited to the following simulation examples.

[0178] In the following examples, a simulation was carried out to calculate the temperature distribution and stress distribution on the mounting surface of a ceramic electrostatic chuck.

[0179] The electrostatic chuck used was made of Al2O3. The temperature control base joined to the electrostatic chuck was made of titanium (Ti). The flow path formed inside the temperature control base was spirally shaped, as shown in Figure 3A, from the center to the outer periphery, in a single stroke. A fluorine-based liquid (Galden (registered trademark)) was used as the fluid that was circulated.

[0180] In the simulation examples shown in Figure 9 and subsequent figures, a low-temperature fluid (first fluid) is circulated in a second direction from the outer periphery of the flow channel toward the center when the temperature is low, and a high-temperature fluid (second fluid) is circulated in the first direction from the center to the outer periphery of the flow channel when the temperature is rising. That is, in the simulation examples, the flow directions of the first fluid and the second fluid are opposite to each other. The flow speed of each fluid is constant.

[0181] In the comparative example, a low-temperature fluid (first fluid) was circulated in a second direction from the outer periphery toward the center of the flow path at low temperatures, and a high-temperature fluid (second fluid) was circulated in the second direction from the outer periphery toward the center of the flow path at elevated temperatures. That is, in the comparative example, the flow directions of the first fluid and the second fluid were the same. The flow speeds of each fluid were constant.

[0182] The temperature distribution simulation was performed by controlling the first fluid at -70°C and the second fluid at 70°C and circulating them through the flow path 15 shown in Figure 3, and calculating the temperature distribution (temperature [°C]) after 10 seconds (Figures 9A and 10A), 20 seconds (Figures 9B and 10B), 30 seconds (Figures 9C and 10C), and 60 seconds (Figures 9D and 10D).

[0183] In the stress distribution simulation, in the example, the stress distribution (equivalent stress [Pa]) on the mounting surface of the electrostatic chuck was measured in the state shown in FIG. 9A, where the temperature difference was the largest, as shown in FIG. 11A, and in the comparative example, the stress distribution (equivalent stress [Pa]) was measured in the state shown in FIG. 10A, where the temperature difference was the largest, as shown in FIG. 11B.

[0184] The comparison results were as follows:

[0185] In the temperature distribution simulation, when the embodiment (FIGS. 9A to 9D) is compared with the comparative example (FIGS. 10A to 10D), it was confirmed that the temperature unevenness of the electrostatic chuck is more suppressed when the first fluid and the second fluid are circulated in opposite directions than when the second fluid is circulated in the same direction as the first fluid.

[0186] In the stress distribution simulation, the stress distribution in the comparative example was a maximum of 86.9 MPa, as shown in FIG. 11B. In contrast, the stress distribution in the example was a maximum of 61.5 MPa, as shown in FIG. 11A. In the comparative example, the low-temperature first fluid and the high-temperature second fluid were circulated in the same direction, while in the example, the low-temperature first fluid was circulated in the first direction and the high-temperature second fluid was circulated in the second direction opposite to the first fluid. Considering that the example corrected the temperature unevenness more effectively than the comparative example, it was confirmed that controlling the flow direction of the fluids reduces stress caused by temperature unevenness.

[0187] Ceramics tend to have extremely low tensile strength compared to their compressive strength. In the comparative example, the low-temperature first fluid and the high-temperature second fluid were circulated in the same second direction, resulting in the outer periphery of the electrostatic chuck becoming hotter and expanding toward the outer periphery, while the inner periphery became colder and did not expand relative to it. This is thought to have led to tensile stress occurring inside the electrostatic chuck of the comparative example, increasing the likelihood of damage due to thermal stress. In contrast, in the example, the low-temperature first fluid was circulated in the first direction and the high-temperature second fluid was circulated in the second direction, opposite to the first fluid. This led to the outer periphery of the electrostatic chuck becoming colder and not expanding, while the inner periphery expanded toward the outer periphery. Therefore, although compressive stress occurred inside the electrostatic chuck of the example, it is thought to be highly effective in preventing damage due to thermal stress because it is made of ceramics with excellent compressive strength. As described above, it was confirmed that the electrostatic chuck can effectively prevent damage caused by temperature changes by appropriately controlling the flow directions of fluids with different temperatures. [Explanation of symbols]

[0188] 1. Plasma processing device, 2. Device body, 2a Upper housing, 2b Lower housing, 3 control device, 10 vacuum chambers, 11 stages, 12 bottom electrode, 12a high frequency power supply, 13 electrostatic chuck, 13a electrode 13b insulating plate, 13c DC power supply, 13d HV terminal, 14 Temperature control base, 15 flow paths, 15a 1st distribution port, 15b 2nd outlet, 16a, 16b piping, 16c Gas piping, 17 exhaust duct, 18 Exhaust system, 19 lift pins, 20 upper electrode, 100, 100A, 100B temperature control system, 110 First chiller, 120 Second chiller, 130 storage section, 131 First Storage Section, 132 Second storage section, 140 Fluid drain, 141 Gas supply section, 142 discharge fluid reservoir; 150 fluid supply control section, 151 Temperature adjustment section, 152 Flow direction switching section, 160 common reservoir, 170 high temperature maintenance storage section, 171 Fluid flow port, 180 temperature rise / fall control unit, v1~v20 valves, P1~P22 piping, PS plasma treatment space Double work.

Claims

1. It can be connected to a plasma processing device capable of performing plasma etching on a workpiece in a vacuum chamber, a holding plate for holding the workpiece placed on a placement surface; a temperature control base joined to the holding plate and having a flow path formed therein through which a fluid can flow so that the holding plate is at a target temperature; a lower housing for holding the temperature control base within the vacuum chamber; a first chiller that supplies a first fluid controlled to a predetermined temperature; a second chiller that supplies a second fluid controlled at a temperature different from that controlled by the first chiller; a fluid supply control unit that selectively supplies at least the first fluid from the first chiller and the second fluid from the second chiller to the temperature control base; The fluid supply control unit includes: a temperature adjusting unit for heating or cooling the first fluid or the second fluid introduced into the temperature control base so that the first fluid or the second fluid reaches the target temperature; a flow direction switching unit that controls the flow direction of each fluid, a temperature control system in which the flow direction switching unit causes the second fluid to flow in a first direction from the center to the outer periphery of the temperature control base when the temperature is rising, and causes the first fluid to flow in a second direction from the outer periphery to the center of the temperature control base when the temperature is falling.

2. It can be connected to a plasma processing device capable of performing plasma etching on a workpiece in a vacuum chamber, a holding plate for holding the workpiece placed on a placement surface; a temperature control base joined to the holding plate and having a flow path formed therein through which a fluid can flow so that the holding plate is at a target temperature; a lower housing for holding the temperature control base within the vacuum chamber; a first chiller that supplies a first fluid controlled to a predetermined temperature; a second chiller that supplies a second fluid controlled at a temperature different from that controlled by the first chiller; a flow direction switching unit that causes the second fluid to flow in a first direction from the center side toward the outer periphery side of the temperature control base when the temperature is rising, and causes the first fluid to flow in a second direction from the outer periphery side toward the center side of the temperature control base when the temperature is decreasing; a high temperature maintenance storage section that stores a third fluid adjusted to a temperature higher than the target temperature and has a fluid flow port for supplying the third fluid; a temperature rise / fall control unit including at least the first chiller and the second chiller, the fluid communication port of the high temperature maintaining storage unit is disposed between the temperature control base and the temperature raising / lowering control unit; a temperature control system in which, when the temperature starts to rise, the flow direction switching unit causes the third fluid to flow through the fluid flow port in a first direction from the center side toward the outer periphery side of the temperature control base, and then stops the flow of the third fluid at a predetermined timing and causes the second fluid to flow in the first direction.

3. 3. The temperature control system according to claim 1, further comprising a storage section arranged upstream of the first chiller and the second chiller, which stores return fluid from the temperature control base, adjusts the return fluid to be equivalent to the control temperature of the first chiller or the second chiller, and then returns the return fluid to the first chiller or the second chiller.

4. The storage unit is a first storage unit disposed upstream of the first chiller, storing the return fluid from the temperature control base, adjusting the temperature of the return fluid to be equivalent to the control temperature of the first chiller, and then returning the return fluid to the first chiller; 4. The temperature control system of claim 3, further comprising: a second storage section arranged upstream of the second chiller, which stores the return fluid from the temperature control base, adjusts the temperature of the return fluid to be equivalent to the control temperature by the second chiller, and then returns the return fluid to the second chiller.

5. the first storage unit circulates the stored return fluid between the first chiller and the return fluid to adjust the temperature to be equivalent to the control temperature of the first chiller; The temperature control system according to claim 4 , wherein the second storage unit circulates the stored return fluid between the second storage unit and the second chiller to adjust the temperature of the return fluid to be equivalent to the control temperature of the second chiller.

6. a common reservoir for storing return fluid from the temperature control base; The common reservoir comprises: When the temperature of the return fluid is different from the control temperature of the first chiller or the second chiller, the return fluid is stored, and a fluid having a temperature equivalent to that of the first chiller or the second chiller is circulated to the first chiller or the second chiller; 3. The temperature control system according to claim 1, wherein the return fluid is circulated directly to the first chiller or the second chiller when the temperature of the return fluid stored in the common reservoir becomes equal to the control temperature of the first chiller or the second chiller.

7. The common reservoir comprises: During high temperature maintenance operation, the stored return fluid is circulated between the first chiller and the return fluid to adjust the temperature to the control temperature of the first chiller; The temperature control system according to claim 6, wherein, when maintaining a low temperature, the stored return fluid is circulated between the second chiller and the second chiller to adjust the temperature to the control temperature of the second chiller.

8. the high temperature maintaining storage unit is disposed between the temperature control base and the temperature increasing / decreasing control unit; The temperature control system according to claim 2 , wherein the fluid flow port of the high temperature maintenance storage unit is disposed between the temperature control base and the flow direction switching unit.

9. 3. The temperature control system according to claim 1, further comprising a gas supply unit that circulates an inert exhaust gas through the flow path to exhaust the fluid in the flow path to the outside when switching the fluid circulating through the temperature control base to another fluid.

10. 4. The temperature control system of claim 3, further comprising a bypass path for returning the fluid from the flow path directly to the first chiller or the second chiller without passing through the storage section when the fluid returns to the same temperature as the control temperature of the first chiller or the second chiller.

11. 7. The temperature control system of claim 6, further comprising a bypass path for returning the fluid from the flow path directly to the first chiller or the second chiller without passing through the common reservoir when the fluid returns to the control temperature of the first chiller or the second chiller.

12. the flow path extends around from the outer periphery toward the center inside the temperature control base, and has a first flow port that guides the fluid toward the center of the flow path when the fluid starts to flow, and a second flow port that guides the fluid toward the outer periphery of the flow path when the fluid starts to flow, 3. The temperature control system of claim 1, wherein the flow direction switching unit causes the second fluid to flow in a first direction from the first flow port of the temperature control base to the second flow port when the temperature is rising, and causes the first fluid to flow in a second direction from the second flow port to the first flow port when the temperature is falling.

13. 3. The temperature control system according to claim 1, wherein the holding plate is an electrostatic chuck having a plurality of protrusions formed on the mounting surface and including an electrode for electrostatically attracting and holding the workpiece.

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