Spool valve

Abstract

To prevent a decline in sliding property of a spool valve element and the occurrence of wear in a sleeve or the spool valve element by controlling a position of interference between the outer peripheral surface of the spool valve element and the inner peripheral surface of a sleeve.SOLUTION: A sleeve 222 includes first surface treatment parts 29 formed at least both axial ends of the inner peripheral surface by electroless nickel plating. The first surface treatment parts 29 each has a smaller inner diameter by a film thickness t11 of first plating than the other part of the inner peripheral surface, for slidably supporting a spool valve element 221.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a spool valve.

Background Art

[0002] An RIE (Reactive Ion Etching) type plasma processing apparatus used in semiconductor manufacturing etches a wafer by introducing a process gas into a processing container while holding the wafer with a susceptor in the processing container. Where a plurality of types of process gases are used for the etching process, different processing conditions are set for each process gas. These processing conditions include the temperature of the wafer to be processed, and the temperature of the susceptor that holds the wafer is controlled to make the wafer temperature match the processing conditions.

[0003] Here, as a technology for controlling the temperature of a susceptor, a temperature adjustment flow control unit that adjusts the temperature of the susceptor by circulating a temperature adjustment fluid through the susceptor, as disclosed in Patent Document 1, is known. In this temperature adjustment flow control unit, the temperature of the temperature adjustment fluid is adjusted by a spool valve that regulates the flow rates of a high-temperature fluid for increasing the temperature of the temperature adjustment fluid and a low-temperature fluid for decreasing the temperature of the temperature adjustment fluid.

[0004] As a spool valve used in a temperature adjustment flow control unit, a spool valve as disclosed in Patent Document 1 is known. This spool valve includes a cylindrical sleeve, the sleeve has two or more input ports and two or more output ports communicating with the interior of the sleeve, and includes a spool valve body that slides along the axial direction inside the sleeve. The opening area of the input ports and the output ports is adjusted by the sliding of the spool.

Prior Art Literature

Patent Literature

[0005]

Patent Document 1

[0006] However, the spool valves relating to the above-mentioned conventional technology had the following problems.

[0007] The gap between the outer surface of the spool valve body and the inner surface of the sleeve (hereinafter simply referred to as clearance) is designed to be uniform in the axial direction of the sleeve. However, since both the sleeve and the spool valve body are generally obtained by machining, there is a risk of distortion in their shape during machining. If this occurs, the clearance may not be uniform in the axial direction of the sleeve, and interference may occur between the outer surface of the spool valve body and the inner surface of the sleeve. Moreover, the location of such interference cannot be controlled, and if interference occurs in multiple places, the sliding performance of the spool valve body within the sleeve will decrease. Furthermore, such interference can lead to wear of the sleeve or spool valve body, resulting in a shorter lifespan for the spool valve.

[0008] The present invention has been made in view of the above problems, and aims to control the interference points between the outer circumferential surface of the spool valve body and the inner circumferential surface of the sleeve, thereby preventing a decrease in the sliding performance of the spool valve body and preventing wear on the sleeve or the spool valve body. [Means for solving the problem]

[0009] To solve the above problems, a spool valve in one aspect of the present invention has the following configuration.

[0010] (1) A spool valve comprising a cylindrical sleeve, the sleeve having two or more input ports and two or more output ports communicating with the inside of the sleeve, and a spool valve body sliding within the sleeve along the axial direction of the sleeve, wherein the opening area of ​​the input ports and the output ports is adjusted by the sliding of the spool valve body, wherein at least one of the sleeve and the spool valve body is provided with support parts at both ends of the sleeve in the axial direction, which make the gap between the inner circumferential surface of the sleeve and the outer circumferential surface of the spool valve body smaller than in other parts, thereby supporting the sliding of the spool valve body. The gap referred to here is the difference between the diameter of the inner circumferential surface of the sleeve and the diameter of the outer circumferential surface of the spool valve body divided by 2, assuming that the spool valve body is located coaxially with the sleeve.

[0011] (2) In the spool valve described in (1), the sleeve is characterized in that it has a first surface treatment made by a first plating at both ends in the axial direction of its inner circumferential surface, and the first surface treatment is the support portion.

[0012] (3) The spool valve described in (1) is characterized in that the spool valve body has a surface treatment by electroplating on the outer circumferential surface of the sleeve, in the portion facing both ends in the axial direction of the inner circumferential surface, and the surface treatment is the support portion.

[0013] (4) In the spool valve described in (2), it is desirable that the axial width of the support portion be 1 mm or more and 15% or less of the total axial length of the sleeve.

[0014] In the spool valve described in (1), at least one of the sleeve and the spool valve body is provided with support portions at both axial ends of the sleeve, which reduce the gap between the inner surface of the sleeve and the outer surface of the spool valve body compared to other parts, thereby supporting the sliding of the spool valve body. Thus, the spool valve body can be actively supported by the support portions. Here, "support" does not mean fixing the spool valve body, but rather guiding the sliding of the spool valve body so that it does not interfere with the inner surface of the sleeve at locations other than the support portions. In other words, the locations where the outer surface of the spool valve body and the inner surface of the sleeve interfere are limited to the support portions, preventing interference at multiple locations. This makes it possible to prevent a decrease in the sliding performance of the spool valve body and wear on the sleeve or spool valve body.

[0015] The support portion is preferably formed by a first surface treatment made by a first plating, which is provided at both axial ends of the inner circumferential surface of the sleeve, as in the spool valve described in (2), or by a surface treatment made by electroplating, which is provided at the portion of the outer circumferential surface of the spool valve body that faces both axial ends of the inner circumferential surface of the sleeve, as in the spool valve described in (3).

[0016] Furthermore, if the support portion is formed by a first surface treatment by a first plating, as in the spool valve described in (2), it is desirable that the axial width of the support portion be 1 mm or more and 15% or less of the total axial length of the sleeve, as in the spool valve described in (4). This is because if the axial width of the support portion is less than 1 mm, that is, if the surface area of ​​the support portion that supports the spool valve body is small, the stress per unit area will increase, and wear of the support portion may occur due to the sliding of the spool valve body. Wear may hinder the sliding of the spool valve body, which is undesirable. Moreover, if the axial width of the support portion is less than 1 mm, it will be difficult to obtain stable quality of surface treatment such as plating, which is undesirable. Also, if the axial width of the support portion is greater than 15% of the total length of the sleeve, that is, if the surface area of ​​the support portion that supports the spool valve body is large, there is a risk that many contact points will occur between the spool valve body and the support portion. This is because processing strain occurs in the spool valve body and sleeve. If numerous contact points occur between the spool valve body and the support part, the sliding performance of the spool valve body may decrease, and the effectiveness in preventing wear on the sleeve or spool valve body may not be sufficiently achieved.

[0017] (5)(2) In the spool valve described above, it is preferable that the spool valve body has a second surface treatment made of a second plating on at least the portion of its outer circumferential surface facing the first surface treatment, and that the hardness of the second plating is higher than the hardness of the first plating.

[0018] The outer circumferential surface of the spool valve body and the inner circumferential surface of the sleeve may be plated to improve wear resistance and corrosion resistance. However, if the hardness of the plating on the outer circumferential surface of the spool valve body and the hardness of the plating on the inner circumferential surface of the sleeve are made to be approximately the same, there is a risk of galling occurring when the spool valve body slides. This galling can lead to a decrease in the sliding performance of the spool valve body, or in the worst case, complete failure to slide. In this context, the inventor has experimentally confirmed that, as in the spool valve described in (4), by making the hardness of the second plating on the outer circumferential surface of the spool valve body higher than the hardness of the first plating on the inner circumferential surface of the sleeve, it is possible to prevent the occurrence of galling and, consequently, the decrease in the sliding performance of the spool valve body.

[0019] In the spool valve described in (6)(5), it is preferable that the first plating is electroless plating and the second plating is electrolytic plating.

[0020] To control the dimensions of the gap between the outer circumferential surface (outer diameter) of the spool and the inner circumferential surface (inner diameter) of the sleeve, it is important to ensure that the first and second surface treatment areas have uniform film thickness dimensions. To achieve the specified inner and outer diameter dimensions after plating, there are means of adjusting the dimensions through post-processing, such as polishing the plated surface. At this time, the outer diameter of the spool is easy to adjust through processing such as outer diameter polishing, but the inner diameter of the sleeve is difficult to process. Therefore, as in the spool valve described in (5), by applying electrolytic plating (second plating), which tends to result in uneven film thickness, to the outer circumferential surface of the spool, and electroless plating (first plating), which is easy to apply with a uniform film, to the inner circumferential surface of the sleeve, it becomes possible to achieve proper control of the gap dimensions. Furthermore, the inventors have confirmed through experiments that by using different treatments for the first and second plating in this way, it is possible to prevent the occurrence of galling when the spool valve body slides.

[0021] (7) In a spool valve according to any one of (1) to (6), the spool valve is a temperature control flow rate control unit for adjusting the temperature of a susceptor by circulating a temperature control fluid to the susceptor of a semiconductor manufacturing apparatus, wherein the spool valve adjusts the temperature of the temperature control fluid by adjusting the flow rate of a high-temperature fluid, which is input to a first input port of the two or more input ports and is output from a first output port of the two or more output ports, for raising the temperature of the temperature control fluid, and the flow rate of a low-temperature fluid, which is input to a second input port of the two or more input ports and is output from a second output port of the two or more output ports, for lowering the temperature of the temperature control fluid, and it is preferable that the gap is 7 μm or more and 55 μm or less in the portion excluding the portion reduced by the support portion.

[0022] To prevent fluid leakage (so-called internal leakage) due to the gap between the inner surface of the sleeve and the outer surface of the spool valve body, it is necessary to seal the gap between the inner surface of the sleeve and the outer surface of the spool valve body. However, sealing reduces the sliding performance of the spool valve body. Spool valves used in temperature control flow rate control units prioritize responsiveness, so a reduction in the sliding performance of the spool valve body due to sealing is undesirable. To minimize internal leakage without sealing, one might consider making the gap between the inner surface of the sleeve and the outer surface of the spool valve body as small as possible. However, making it too small causes interference between the sleeve and the spool valve body, which actually reduces the sliding performance of the spool valve body. Therefore, as in the spool valve described in (4), if the spool valve body is supported by a support part, and the gap between the outer surface of the spool valve body and the inner surface excluding the first surface treatment part is 7 μm or more and 55 μm or less, it is possible to suppress internal leakage of high-temperature and low-temperature fluids while ensuring the sliding performance of the spool valve body.

[0023] (8) In the spool valve described in (1), it is preferable that the sleeve is provided with support portions formed by reducing the inner diameter at both axial ends of the inner circumferential surface, and that the amount of reduction in the diameter of the support portions is 4 μm or more and 60 μm or less.

[0024] In the spool valve according to (9) and (8), it is preferable that an axial width of the support portion is not less than 2% and not more than 15% of a total axial length of the sleeve.

[0025] According to the spool valve described in (8) or (9), the sleeve includes support portions formed by reducing the inner diameter at both axial ends of the inner circumferential surface, so that the support portions can actively support the spool valve body. Accordingly, the interference between the spool valve body and the sleeve is limited to the support portions, and interference at multiple locations can be prevented. In this case, it is preferable that the diameter reduction amount of the support portion is not less than 4 µm and not more than 60 µm. This is because if the diameter reduction amount is smaller than 4 µm, the spool valve body cannot be sufficiently supported, and interference may occur at locations other than the support portions; and if the diameter reduction amount is larger than 60 µm, internal leakage of fluid between the inner circumferential surface of the sleeve and the spool valve body may occur.

[0026] Furthermore, it is preferable that the axial width of the support portion is not less than 2% and not more than 15% of the total axial length of the sleeve. This is because if the axial width of the support portion is smaller than 2% of the total axial length of the sleeve, that is, if the surface area of the support portion for supporting the spool valve body is small, the stress per unit area increases, and wear of the support portion may occur due to sliding of the spool valve body. If wear occurs, sliding of the spool valve body may be hindered, which is undesirable. Furthermore, if the axial width of the support portion is smaller than 2% of the total axial length of the sleeve, stable quality of surface treatment such as plating cannot be obtained, which is not preferable. In addition, if the axial width of the support portion is larger than 15% of the total axial length of the sleeve, that is, if the surface area of the support portion for supporting the spool valve body is large, there is a possibility that many contact points occur between the spool valve body and the support portion. This is because processing strain occurs in the spool valve body and the sleeve. If many contact points occur between the spool valve body and the support portion, the sliding performance of the spool valve body may be degraded, and the effect of preventing wear of the sleeve or the spool valve body may not be sufficiently obtained. [Effects of the Invention]

[0027] According to the spool valve of the present invention, it is possible to control the interference position between the outer circumferential surface of the spool valve body and the inner circumferential surface of the sleeve, and prevent the reduction in the slidability of the spool valve body and the occurrence of wear on the sleeve or the spool valve body. [Brief Description of the Drawings]

[0028] [Figure 1] FIG. 1 is a circuit diagram of a flow rate control unit for temperature adjustment using the spool valve according to the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the spool valve. [Figure 3] FIG. 3 is a partially enlarged view of part A in FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view showing the shape of the sleeve. [Figure 5] FIG. 5 is a partially enlarged view corresponding to FIG. 3 of the spool valve according to the second embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing the shape of the sleeve of the spool valve according to the third embodiment. [Mode for Carrying Out the Invention]

[0029] (First Embodiment) A first embodiment of the spool valve 21 according to the present invention will be described in detail below with reference to the drawings

[0030] (Schematic Configuration of Flow Rate Control Unit for Temperature Adjustment) First, the schematic configuration of a temperature adjustment flow rate control unit 1 (hereinafter also referred to as "unit 1") using the spool valve 21 according to the present embodiment will be described. FIG. 1 is a circuit diagram of the temperature adjustment flow rate control unit 1 using the spool valve 21 according to the present embodiment. This unit 1 is used, for example, in a temperature control system 1001 that controls the temperature of a semiconductor manufacturing apparatus 1000.

[0031] The semiconductor manufacturing apparatus 1000 in this embodiment is configured as a Reactive Ion Etching (RIE) type plasma processing apparatus. In the semiconductor manufacturing apparatus 1000, a wafer W is placed on a susceptor 1002 arranged in a processing container (not shown), and an etching process is performed on the wafer W, which is controlled to a predetermined temperature.

[0032] Multiple types of process gases are used in the etching process, and different processing conditions are set for each process gas. These processing conditions include the temperature of the wafer W to be processed, and in order to match the temperature of the wafer W to the processing conditions, the temperature of the susceptor 1002 that holds the wafer W is controlled by the temperature control system 1001.

[0033] The temperature control system 1001 comprises a temperature adjustment unit 1003 (hereinafter abbreviated as "temperature control unit 1003"), a unit 1, and a chiller unit 1004.

[0034] The temperature control unit 1003 is located inside the susceptor 1002 and circulates the temperature control fluid output from the temperature control flow rate control unit 1 to the susceptor 1002. The temperature control fluid is a fluorine-based inert fluid that exhibits little change in physical properties over a wide temperature range. An example of a fluorine-based inert fluid is Fluorinert manufactured by 3M.

[0035] The chiller unit 1004 includes a cold chiller 1020 and a hot chiller 1010. The cold chiller 1020 circulates a fluorine-based inert liquid (hereinafter referred to as "low-temperature fluid") controlled to a temperature lower than the valve mixture temperature (temperature control temperature) in order to lower the temperature of the temperature-controlled fluid. The circulation pressure of the low-temperature fluid is controlled by the low-temperature side control valve 1023. The hot chiller 1010 circulates a fluorine-based inert liquid (hereinafter referred to as "high-temperature fluid") controlled to a temperature higher than the valve mixture temperature (temperature control temperature) in order to raise the temperature of the temperature-controlled fluid. The circulation pressure of the high-temperature fluid is controlled by the high-temperature side control valve 1013. Note that the temperatures of the low-temperature and high-temperature fluids described above are merely examples and should be set appropriately according to the required temperature of the temperature-controlled fluid.

[0036] Unit 1 may include a first coupling pipe 1005 for inputting a temperature-controlled fluid to the susceptor 1002, and a second coupling pipe 1006 for outputting the temperature-controlled fluid after it has circulated through the susceptor 1002 (hereinafter referred to as the post-circulation temperature-controlled fluid). Unit 1 is connected to the susceptor 1002 by the first coupling pipe 1005 and the second coupling pipe 1006.

[0037] Unit 1 comprises an input pipe 3 connected to a first coupling pipe 1005, an output pipe 4 connected to a second coupling pipe 1006, a low-temperature fluid input pipe 5 and a low-temperature fluid output pipe 6 through which low-temperature fluid flows, a high-temperature fluid input pipe 7 and a high-temperature fluid output pipe 8 through which high-temperature fluid flows, a pump 14 for circulating the temperature-controlled fluid, a fluid control unit 9, and a control device 1030.

[0038] The input piping 3 is configured, in order from upstream, with a third filter block 43, a buffer tank 12, and a pump 14.

[0039] The post-circulation temperature-controlled fluid is input to the input pipe 3 from the first coupling pipe 1005. A second temperature sensor 61 (an example of a second temperature measuring unit) is installed in the first coupling pipe 1005, making it possible to measure the current temperature of the post-circulation temperature-controlled fluid. The temperature control system 1001 obtains the current temperature of the susceptor 1002 by measuring the current temperature of the post-circulation temperature-controlled fluid. Since the post-circulation temperature-controlled fluid is the temperature-controlled fluid after it has circulated through the susceptor 1002, its temperature can be considered equivalent to the temperature of the susceptor 1002. Furthermore, since the second temperature sensor 61 is installed in the first coupling pipe 1005, it is located upstream of the pump 14. Therefore, the temperature of the post-circulation temperature-controlled fluid can be measured without being affected by the heat generated by the pump 14. In RIE-type plasma processing equipment, it is difficult to directly measure the temperature of the susceptor due to the influence of the plasma-generated process gas, etc. However, by measuring the current temperature of the post-circulation temperature-controlled fluid after it has circulated through the susceptor 1002, it becomes possible to stably monitor the temperature of the susceptor 1002.

[0040] The output pipe 4 outputs the temperature-controlled fluid to the second connecting pipe 1006. The output pipe 4 is equipped with a flow sensor 53 and a first temperature sensor 64 (an example of a first temperature measuring unit) in order from the upstream side. The first temperature sensor 64 measures the temperature of the temperature-controlled fluid output from the output pipe 4. The fluid control unit 9 is connected to the temperature control unit 1003 via the input pipe 3 and the output pipe 4, and the temperature-controlled fluid circulates between the temperature control unit 1003 and the fluid control unit 9 as shown by the dashed arrow D1 in Figure 1.

[0041] The input pipe 5 and output pipe 6 for the cryogenic fluid connect the fluid control unit 9 to the cold chiller 1020, and the cryogenic fluid is input to and output from the fluid control unit 9 as shown by the dashed arrow D2 in Figure 1. The temperature and pressure of the cryogenic fluid input to the fluid control unit 9 are measured by a third temperature sensor 62 and a first pressure sensor 51, which are located on the input pipe 5 for the cryogenic fluid. A first filter block 41 is also installed on the input pipe 5 for the cryogenic fluid, and the first filter block 41 removes foreign matter from the cryogenic fluid input to the fluid control unit 9.

[0042] The high-temperature fluid input pipe 7 and high-temperature fluid output pipe 8 connect the fluid control unit 9 to the hot chiller 1010, and as shown by the dashed arrow D3 in Figure 1, the high-temperature fluid is input to and output from the fluid control unit 9. The temperature and pressure of the high-temperature fluid flowing into the fluid control unit 9 are measured by a fourth temperature sensor 63 and a second pressure sensor 52, which are installed on the high-temperature fluid input pipe 7. A second filter block 42 is also installed on the high-temperature fluid input pipe 7, and the second filter block 42 removes foreign matter from the high-temperature fluid that is input from the high-temperature fluid input pipe 7 to the fluid control unit 9.

[0043] The fluid control unit 9 has a branching section X that branches the input piping 3 into a first branch line L11, a second branch line L12, and a third branch line L13. The first branch line L11 is connected to a spool valve 21 and is equipped with a first check valve 54. A purge mechanism 10 equipped with a purge on / off valve 101 is also connected to the first branch line L11, so that purge air can be supplied to unit 1 by opening the purge on / off valve 101, for example, during maintenance of the semiconductor manufacturing equipment 1000. The second branch line L12 is connected to an output piping 6 for low-temperature fluids and is equipped with a second check valve 55. Furthermore, the third branch line L13 is connected to an output piping 8 for high-temperature fluids and is equipped with a third check valve 56.

[0044] The input pipe 5 for low-temperature fluid, the input pipe 7 for high-temperature fluid, and the first branch line L11 are each connected to the spool valve 21. The spool valve 21 controls the flow rate (flow rate distribution ratio) of the fluids supplied from each of the input pipes, and the first branch line L11, and discharges them. The fluids discharged from the spool valve 21 are mixed at the confluence Y and output to the output pipe 4 connected to the confluence Y. Details of the configuration of the spool valve 21 will be described later.

[0045] The fluid mixed at the confluence Y and output to the output pipe 4 is the temperature-controlled fluid used to regulate the temperature of the susceptor 1002. In other words, the spool valve 21 adjusts the temperature of the temperature-controlled fluid by adjusting the flow rate distribution ratio of the circulated temperature-controlled fluid input from the input pipe 3 to the spool valve 21, the low-temperature fluid input from the low-temperature fluid input pipe 5 to the spool valve 21, and the high-temperature fluid input from the high-temperature fluid input pipe 7 to the spool valve 21, and outputs it to the output pipe 4.

[0046] The flow rate distribution ratio adjustment performed by the spool valve 21 (i.e., the temperature adjustment of the temperature-controlled fluid output to the output pipe 4) is controlled based on a temperature control value generated by the control device 1030, which will be described later.

[0047] The valve openings of the first to third check valves 54, 55, and 56 are automatically adjusted according to the flow rate distribution ratio controlled by the spool valve 21. As a result, approximately the same amount of post-circulation temperature control fluid as the low-temperature fluid and high-temperature fluid supplied to the spool valve 21 are returned to the cold chiller 1020 and the hot chiller 1010.

[0048] Unit 1 includes a control device 1030 that controls the operation of the temperature control system 1001, and the control device 1030 is connected to various sensors and valves of Unit 1 in a communicative manner. The control device 1030 includes a control board 1031, a pump driver 1033, and a valve controller 1032.

[0049] The control board 1031 generates a temperature control value for adjusting the temperature of the temperature-controlled fluid. It then acquires temperature measurements from temperature sensors 61, 62, 63, and 64, and pressure measurements from first and second pressure sensors 51 and 52 from unit 1, generates a valve operation signal so that the temperature of the temperature-controlled fluid conforms to the temperature control value, and transmits it to unit 1 via valve controller 1032. Unit 1 adjusts the flow rate distribution ratio of the temperature-controlled fluid, low-temperature fluid, and high-temperature fluid by operating the spool valve 21 according to the valve operation signal, thereby adjusting the temperature of the temperature-controlled fluid to the set temperature. Thus, the temperature of the temperature-controlled fluid is feedback-controlled and made uniform.

[0050] Furthermore, the control board 1031 acquires the flow rate measurement value from the flow sensor 53 from unit 1, generates a pump operation signal to control the flow rate of the temperature-controlled fluid to a desired set flow rate, and transmits it to unit 1 via the pump driver 1033. Unit 1 adjusts the flow rate of the temperature-controlled fluid to the set flow rate by having the pump 14 operate according to the pump operation signal. Thus, the circulating flow rate of the temperature-controlled fluid is feedback-controlled and made uniform.

[0051] (Regarding the spool valve configuration) Next, the configuration of the spool valve 21 according to this embodiment will be described in detail with reference to the drawings. Figure 2 is a cross-sectional view of the spool valve 21. Figure 3 is a partially enlarged view of part A in Figure 2. Figure 4 is a cross-sectional view showing the shape of the sleeve 222.

[0052] As shown in Figure 2, the spool valve 21 according to this embodiment includes a valve section 22, a drive unit 23 connected to one of the axial ends of the valve section, and a position sensor 25 connected to the other end of the valve section 22.

[0053] The drive unit 23 is a linear actuator. The drive unit 23 has a movable element 65 made of a ferromagnetic material such as steel, a pair of permanent magnets 66, 66 arranged on either side of the movable element 65, and a coil 67 that generates a magnetic field in the same direction as the pair of permanent magnets 66, 66. The movable element 65 is movable in a direction perpendicular to the direction of the magnetic field of the permanent magnets 66, 66, and is fixed to one end of the spool valve body 221 (described later) with its direction of movement being the same as the sliding direction of the spool valve body 221. The position of the movable element 65 (i.e., the axial position (stroke position) of the spool valve body 221) is determined according to the direction of energization to the coil 67 and the magnitude of the voltage and current based on the valve operation signal generated by the control board 1031. Furthermore, the movable element 65 is sandwiched between springs 68 on both sides in the axial direction, and when the coil 67 is not energized and no control fluid is flowing into the spool valve 21, it is held near the neutral position by the biasing force of the springs 68 (i.e., the stroke position is held near the neutral position).

[0054] The valve section 22 comprises a spool valve body 221, a sleeve 222 that slidably holds the spool valve body 221, and a body 223 that houses the spool valve body 221 and the sleeve 222.

[0055] The body 223 is a roughly rectangular parallelepiped case and is provided with first body through-holes 224A, 224B, 224C and second body through-holes 225A, 225B, 225C that connect its interior and exterior. The input pipe 5 for low-temperature fluid is connected to the first body through-hole 224A, so that low-temperature fluid is supplied to the spool valve 21. The first branch line L11 is connected to the first body through-hole 224B, so that a fluid for temperature control after circulation is supplied to the spool valve 21. The input pipe 7 for high-temperature fluid is connected to the first body through-hole 224C, so that high-temperature fluid is supplied to the spool valve 21. The second body through-hole 225A supplies the spool valve 21, and the flow-regulated low-temperature fluid is discharged from the spool valve 21. The second body through-hole 225B supplies the spool valve 21 and discharges the circulating temperature-controlled fluid, whose flow rate has been adjusted, from the spool valve 21. The second body through-hole 225C supplies the spool valve 21 and discharges the high-temperature fluid, whose flow rate has been adjusted, from the spool valve 21. The second body through-holes 225A, 225B, and 225C are all connected to a confluence Y for mixing the fluids discharged from the spool valve 21.

[0056] The sleeve 222 housed in the body 223 is formed in a cylindrical shape from stainless steel. The sleeve 222 has a valve chamber 24 through which the spool valve body 221 is inserted.

[0057] Furthermore, the sleeve 222 is provided with input ports 26A, 26B, and 26C that lead to the valve chamber 24. Input port 26A is located at a position corresponding to the first body through-hole 224A, input port 26B is located at a position corresponding to the first body through-hole 224B, and input port 26C is located at a position corresponding to the first body through-hole 224C. This makes it possible to allow fluid supplied from the first body through-holes 224A, 224B, and 224C to flow into the valve chamber 24.

[0058] Furthermore, the sleeve 222 is equipped with output ports 27A, 27B, and 27C that lead to the valve chamber 24. Output port 27A is located at a position corresponding to the second body through-hole 225A, output port 27B is located at a position corresponding to the second body through-hole 225B, and output port 27C is located at a position corresponding to the second body through-hole 225C. This makes it possible to discharge the fluid flowing into the valve chamber 24 through the output ports 27A, 27B, and 27C and out of the second body through-holes 225A, 225B, and 225C.

[0059] Furthermore, as shown in Figure 4, the sleeve 222 (valve chamber 24) has first surface treatment areas 29, 29 made of electroless nickel plating (an example of the first plating) at both axial ends on its inner circumferential surface. As a result, as shown in Figure 3, the inner diameter of the first surface treatment areas 29 on the inner circumferential surface of the sleeve 222 (valve chamber 24) is smaller than that of the other parts of the inner circumferential surface of the sleeve 222 (valve chamber 24) by the thickness t11 of the electroless nickel plating. This makes it possible for the first surface treatment areas 29, 29 to actively support the spool valve body 221 that slides within the sleeve 222 (valve chamber 24). In other words, the spool valve body 221 is supported at both axial ends of the sleeve 222. In this way, by limiting the points where the outer circumferential surface 221a of the spool valve body 221 and the inner circumferential surface of the sleeve 222 (valve chamber 24) interfere when the spool valve body 221 slides to the first surface treatment areas 29, 29, it is possible to prevent interference at multiple points. This makes it possible to prevent a decrease in the sliding performance of the spool valve body 221 and prevent wear on the sleeve 222 or the spool valve body 221. Note that the film thickness t11 in Figure 2 does not represent the actual thickness, size, etc., for the sake of simplicity of understanding. Therefore, it is not necessarily limited to the size etc. shown in the drawing.

[0060] The film thickness t11 of the electroless nickel plating is not particularly limited, but in this embodiment it is approximately 3 to 25 μm. The electroless nickel plating of the first surface treatment area 29 is baked at 200°C, and its hardness is approximately 400-500 Hv on the Vickers hardness scale. The baking temperature is set to 200°C to improve the adhesion of the plating and make it less likely to peel off, but this is merely one example. It is known that increasing the baking temperature of electroless nickel plating increases its hardness, so the baking temperature can be adjusted according to the required hardness.

[0061] Furthermore, the axial plating range PA12 of the first surface treatment section 29 is set appropriately according to the amount of sliding of the spool valve body 221, within a range of 1 mm or more and 15% or less of the total axial length L51 of the sleeve 222 (see Figure 4).

[0062] The spool valve body 221 is formed in a cylindrical shape from stainless steel. Spool circumferential grooves 28A, 28B, and 28C are formed on the outer circumferential surface of the spool valve body 221, aligned in the axial direction. The spool circumferential groove 28A is formed around the entire circumference of the spool valve body 221, and its axial width is greater than the axial distance between the input port 26A and the output port 27A.

[0063] When the spool groove 28A overlaps the input port 26A and the output port 27A, both the input port 26A and the output port 27A are connected to the spool groove 28A, and the input port 26A and the output port 27A are in communication via the spool groove 28A. As a result, a series of flow paths are formed from the first body through hole 224A to the second body through hole 225A via the input port 26A, the spool groove 28A, and the output port 27A. The overlap width between the spool groove 28A and the input port 26A and the output port 27A increases or decreases according to the stroke position of the spool valve body 221. In other words, the open area of ​​the input port 26A and the output port 27A is adjusted according to the stroke position of the spool valve body 221, and the flow rate of the fluid flowing through the series of flow paths described above is controlled. Furthermore, if at least one of the input port 26A and the output port 27A does not overlap with the spool circumferential groove 28A, the series of flow paths described above will be blocked. In other words, the fluid will be unable to flow through the series of flow paths described above. The relationship between the input ports 26B, 26C, the output ports 27B, 27C, and the spool circumferential grooves 28B, 28C is the same as described above.

[0064] The outer circumferential surface 221a of the spool valve body 221 has a uniform diameter throughout the axial direction, except for the parts where the spool grooves 28A, 28B, and 28C are provided. The outer diameter of the spool valve body 221 is set so that the gap g11 between the outer circumferential surface 221a of the spool valve body 221 and the inner circumferential surface of the sleeve 222 (valve chamber 24) is between 7 μm and 55 μm. This is to ensure the sliding properties of the spool valve body 221 while suppressing fluid leakage (so-called internal leakage) due to the gap g11. The gap g11 here is calculated by assuming that the spool valve body 221 is coaxially positioned with the sleeve 222, and dividing the difference between the diameter of the inner circumferential surface of the sleeve 222 and the diameter of the outer circumferential surface of the spool valve body 221 by 2.

[0065] If the gap g11 becomes larger than 55 μm, internal leakage may increase between the series of flow paths from the first body through-hole 224A to the second body through-hole 225A, the series of flow paths from the first body through-hole 224B to the second body through-hole 225B, and the series of flow paths from the first body through-hole 224C to the second body through-hole 225C. To suppress internal leakage, it is conceivable to make the gap g11 as small as possible, but if the size of the gap g11 becomes smaller than 7 μm, interference between the sleeve 222 and the spool valve body 221 may occur, which may actually reduce the sliding performance of the spool valve body 221. Therefore, as described above, the gap g11 is set to be between 7 μm and 55 μm.

[0066] Furthermore, the outer circumferential surface 221a of the spool valve body 221, including the spool circumferential grooves 28A, 28B, and 28C, is a second surface treatment area 30 that has been surface-treated by electroplating (specifically, hard chromium plating (an example of the second plating)). The hardness of this hard chromium plating is approximately 800 Hv on the Vickers hardness scale.

[0067] When the spool valve body 221 slides within the valve chamber 24, the first surface treatment 29 actively supports the spool valve body 221, causing the first surface treatment 29 and the second surface treatment 30 (the outer circumferential surface 221a of the spool valve body 221) to rub against each other. In this situation, the first surface treatment 29 of the sleeve 222 is electroless nickel plating, while the second surface treatment 30 is hard chromium plating. Furthermore, the hardness of the first surface treatment 29 is 400-500 Hv on the Vickers scale, while the hardness of the second surface treatment 30 is approximately 800 Hv on the Vickers scale, which is higher than that of the first surface treatment 29. As a result, dissimilar platings with different hardnesses rub against each other. This prevents the occurrence of galling of the plating and, consequently, prevents a decrease in the sliding performance of the spool valve body.

[0068] Furthermore, while plating the inner surface of the sleeve 222 is not easy, plating the outer surface of the spool valve body 221 is relatively easy. For this reason, as described above, the first surface treatment area 29 is plated with electroless nickel plating, which is expensive but allows for easy control of film thickness, while the second surface treatment area 30 is plated with hard chromium plating, which is less expensive than electroless plating, thereby optimizing manufacturing costs.

[0069] The position sensor 25 is a sensor for detecting the stroke position of the spool valve body 221, and based on the detection result of this position sensor 25, feedback control of the stroke position can be performed. For example, a magnetostrictive sensor can be used as the position sensor 25.

[0070] As described above, the spool valve 21 according to this embodiment is (1) A spool valve 21 comprising a cylindrical sleeve 222, the sleeve 222 having two or more input ports 26A, 26B, 26C and two or more output ports 27A, 27B, 27C communicating with the inside of the sleeve 222, and a spool valve body 221 sliding inside the sleeve 222 along the axial direction of the sleeve 222, wherein the opening area of ​​the input ports 26A, 26B, 26C and the output ports 27A, 27B, 27C is adjusted by the sliding of the spool valve body 221, wherein at least one of the sleeve 222 and the spool valve body 221 has a support portion at both axial ends of the sleeve 222 that makes the gap g11 between the inner circumferential surface of the sleeve 222 and the outer circumferential surface of the spool valve body 221 smaller than in other parts, thereby supporting the sliding of the spool valve body 221.

[0071] (2) In the spool valve 21 described in (1), the sleeve 222 is characterized in that it has a first surface treatment 29 made of a first plating (for example, electroless nickel plating) at both axial ends of its inner circumferential surface, and the first surface treatment 29 is the support portion.

[0072] According to the spool valve 21 described in (1) and (2), the sleeve 222 is provided with support portions (first surface treatment portions 29) at both axial ends of the sleeve 222 that reduce the gap between the inner surface of the sleeve 222 and the outer surface of the spool valve body 221 compared to other parts, thereby supporting the sliding of the spool valve body. Thus, the support portions (first surface treatment portions 29) can actively support the spool valve body 221. Here, "support" does not mean fixing the spool valve body 221, but rather guiding the sliding of the spool valve body 221 so that it does not interfere with the inner surface of the sleeve 222 at locations other than the support portions (first surface treatment portions 29). In other words, the location where the outer surface of the spool valve body 221 and the inner surface of the sleeve 222 interfere is limited to the support portions (first surface treatment portions 29), preventing interference at multiple locations. This makes it possible to prevent a decrease in the sliding performance of the spool valve body 221 and to prevent wear on the sleeve 222 or the spool valve body 221.

[0073] Furthermore, in the spool valve described in (4)(2), it is desirable that the axial width PA12 of the support portion (first surface treatment portion 29) be 1 mm or more and 15% or less of the total axial length L51 of the sleeve 222. This is because if the width of the support portion (first surface treatment portion 29) is less than 1 mm, that is, if the surface area of ​​the support portion (first surface treatment portion 29) that supports the spool valve body 221 is small, the stress per unit area will increase, and wear of the support portion (first surface treatment portion 29) may occur due to the sliding of the spool valve body 221. Wear may hinder the sliding of the spool valve body 221, which is undesirable. Moreover, if the axial width of the support portion (first surface treatment portion 29) is less than 1 mm, it will be difficult to obtain stable quality of surface treatment such as plating (for example, electroless nickel plating), which is undesirable. Furthermore, if the width PA12 of the support portion (first surface treatment portion 29) is greater than 15% of the total length L51 of the sleeve, that is, if the surface area of ​​the support portion (first surface treatment portion 29) that supports the spool valve body 221 is large, there is a risk that numerous contact points will occur between the spool valve body 221 and the support portion (first surface treatment portion 29). This is because processing strain occurs in the spool valve body 221 and the sleeve 222. If numerous contact points occur between the spool valve body 221 and the support portion (first surface treatment portion 29), there is a risk that the sliding performance of the spool valve body 221 will decrease, and the effect of preventing wear on the sleeve 222 or the spool valve body 221 will not be sufficiently obtained.

[0074] In the spool valve 21 described in (5)(2), it is desirable that the spool valve body 221 has a second surface treatment 30 made of a second plating (e.g., hard chromium plating) on ​​at least the portion of its outer circumferential surface facing the first surface treatment 29, and that the hardness of the second plating (hard chromium plating) (e.g., about 800 Hv on the Vickers hardness scale) is higher than the hardness of the first plating (electroless nickel plating) (e.g., 400-500 Hv on the Vickers hardness scale).

[0075] The inventors of this invention have experimentally confirmed that if the hardness of the first plating and the second plating are of similar magnitude, there is a risk of galling of the plating occurring when the spool valve body 221 slides. This galling can cause a decrease in the sliding performance of the spool valve body 221. In this context, the inventors have experimentally confirmed that, as in the spool valve 21 described in (2), by making the hardness of the second plating (hard chromium plating) on ​​the outer circumferential surface of the spool valve body 221 higher than the hardness of the first plating (electroless nickel plating) on ​​the inner circumferential surface of the sleeve 222, it is possible to prevent the occurrence of galling and, consequently, prevent a decrease in the sliding performance of the spool valve body 221.

[0076] In the spool valve 21 described in (6)(5), it is preferable that the first plating is electroless plating (electroless nickel plating) and the second plating is electrolytic plating (hard chromium plating).

[0077] In order to control the dimensions of the gap g11 between the outer circumferential surface (outer diameter) of the spool valve body 221 and the inner circumferential surface (inner diameter) of the sleeve 222, it is important to make the first surface treatment area 29 and the second surface treatment area 30 have uniform film thickness dimensions. In order to finish the inner and outer diameter dimensions to the specified dimensions after plating, there are means of adjusting the dimensions by post-processing such as polishing the plated surface. At this time, the outer diameter of the spool valve body 221 is easy to adjust by processing such as outer diameter polishing, but the inner diameter of the sleeve 222 is difficult to process. Therefore, as with the spool valve 21 described in (5), by applying electroplating (second plating), which tends to result in an uneven film thickness, to the outer circumferential surface of the spool valve body 221, and electroless plating (first plating), which is easy to process with a uniform film, to the inner circumferential surface of the sleeve 222, it becomes possible to properly control the dimensions of the gap g11. Furthermore, the inventors have confirmed through experiments that by using different treatments for the first and second plating processes, it is possible to prevent the occurrence of galling when the spool valve body 221 slides.

[0078] (7) In the spool valve 21 described in (1) to (6), the spool valve 21 adjusts the temperature of the susceptor 1002 of the semiconductor manufacturing apparatus 1000 by circulating a temperature-controlled fluid around the susceptor 1002, in a temperature-controlled flow rate control unit 1 that adjusts the temperature of the susceptor 1002 by adjusting the flow rate of a low-temperature fluid, which is input to the first input port 26A of the two or more input ports and is output from the first output port 27A of the two or more output ports, for lowering the temperature of the temperature-controlled fluid, and the flow rate of a high-temperature fluid, which is input to the second input port 26C of the two or more input ports and is output from the second output port 27C of the two or more output ports, for raising the temperature of the temperature-controlled fluid. It is desirable that the gap g11 between the outer circumferential surface of the spool valve body 221 and the inner circumferential surface excluding the first surface-treated section 29 is 7 μm or more and 55 μm or less.

[0079] To prevent fluid leakage (so-called internal leakage) due to the gap g11 between the inner surface of the sleeve 222 and the outer surface of the spool valve body 221, a seal is necessary between the inner surface of the sleeve 222 and the outer surface of the spool valve body 221. However, sealing reduces the sliding performance of the spool valve body 221. Since the spool valve 21 used in the temperature control flow rate control unit 1 prioritizes responsiveness, it is undesirable for the sliding performance of the spool valve body 221 to be reduced by sealing. To minimize internal leakage as much as possible without sealing, one could consider making the gap g11 between the inner surface of the sleeve 222 and the outer surface of the spool valve body 221 as small as possible. However, if it is made too small, interference between the sleeve 222 and the spool valve body 221 will occur, which will actually reduce the sliding performance of the spool valve body 221. Therefore, as with the spool valve described in (4), in addition to supporting the spool valve body 221 with the first surface treatment 29, if the gap g11 between the outer circumferential surface of the spool valve body 221 and the inner circumferential surface excluding the first surface treatment 29 is 7 μm or more and 55 μm or less, it becomes possible to suppress internal leakage of high-temperature and low-temperature fluids while ensuring the sliding properties of the spool valve body 221.

[0080] (Second embodiment) Next, we will describe only the differences between the spool valve according to the second embodiment and the first embodiment. Figure 5 is a partially enlarged view of the spool valve according to the second embodiment, corresponding to Figure 3.

[0081] In the spool valve according to the second embodiment, the spool valve body 221 is provided with support portions at both axial ends of the sleeve 222, which reduce the gap g11 between the inner circumferential surface of the sleeve 222 and the outer circumferential surface of the spool valve body 221 compared to other portions, thereby supporting the sliding of the spool valve body 221. These support portions consist of surface treatment portions 31 formed by electroplating on the outer circumferential surface of the spool valve body 221, on the portions facing both axial ends of the inner circumferential surface of the sleeve 222.

[0082] The film thickness t12 of the electroplating is not particularly limited, but in this embodiment it is approximately 3 to 25 μm. Furthermore, the axial plating range PA22 of the first surface treatment area 29 is set appropriately considering tolerances, with a minimum of twice the axial sliding distance of the spool valve body 221.

[0083] The entire inner surface of the sleeve 222 is a surface treatment 32 made by electroless nickel plating. This electroless nickel plating is baked at 200°C, and its hardness is approximately 400-500 Hv on the Vickers hardness scale. The baking temperature is set to 200°C to improve the adhesion of the plating and make it less likely to peel off, but this is just one example. It is known that the hardness of electroless nickel plating increases with increasing the baking temperature, so the baking temperature can be adjusted according to the required hardness.

[0084] Thus, by providing the spool valve body 221 with a support portion (surface treatment portion 31) that supports the sliding of the spool valve body, the points where the outer circumferential surface of the spool valve body 221 and the inner circumferential surface of the sleeve 222 interfere are limited to the support portion (surface treatment portion 31), thus preventing interference at multiple points. This makes it possible to prevent a decrease in the sliding performance of the spool valve body 221 and to prevent wear on the sleeve 222 or the spool valve body 221.

[0085] (Third embodiment) Next, we will describe only the differences between the spool valve according to the third embodiment and the first embodiment. Figure 6 is a cross-sectional view showing the shape of the sleeve 226 of the spool valve according to the third embodiment. Note that the referenced drawings have been simplified for the sake of clarity and do not accurately represent the shape or dimensions.

[0086] At both ends in the axial direction, the inner circumferential surface 228 of the sleeve 226 is gently tapered outward in the axial direction by the inclined portion 229. This forms support portions 227 at both ends in the axial direction of the sleeve 226. With the support portions 227 formed in this way, the spool valve body 221 inserted into the sleeve 226 is actively supported by the support portions 227. As a result, the points where the spool valve body 221 and the sleeve 226 interfere are limited to the support portions 227, preventing interference at multiple points. Note that the spool valve body 221 referred to here is the same as the spool valve body 221 in the first embodiment.

[0087] In this case, the amount of diameter reduction, that is, the value obtained by subtracting the inner diameter D11 of the support portion 227 from the inner diameter D12 of the sleeve 226, is preferably between 4 μm and 60 μm. This is because if the amount of diameter reduction is less than 4 μm, the spool valve body 221 will not be adequately supported, and interference may occur at locations other than the support portion 227. Also, if the amount of diameter reduction is greater than 60 μm, there is a risk of internal fluid leakage between the inner circumferential surface 228 of the sleeve 226 and the spool valve body 221.

[0088] Furthermore, it is desirable that the axial width A11 of the support portion 227 be between 2% and 15% of the total axial length L52 of the sleeve 226. This is because if the width A11 of the support portion 227 is less than 2% of the total length L52 of the sleeve 226, that is, if the surface area of ​​the support portion 227 that supports the spool valve body 221 is small, the stress per unit area will increase, and wear of the support portion 227 may occur due to the sliding of the spool valve body 221. Wear may hinder the sliding of the spool valve body 221, which is undesirable. Moreover, if the axial width A11 of the support portion 227 is less than 2% of the total axial length L52 of the sleeve, stable quality of surface treatment such as plating (e.g., electroless nickel plating) cannot be obtained, which is undesirable. Furthermore, if the width A11 of the support portion 227 is greater than 15% of the total length L52 of the sleeve 226, that is, if the surface area of ​​the support portion 227 that supports the spool valve body 221 is large, there is a risk that numerous contact points will occur between the spool valve body 221 and the support portion 227. This is because processing strain occurs in the spool valve body 221 and the sleeve 226. If numerous contact points occur between the spool valve body 221 and the support portion 227, there is a risk that the sliding performance of the spool valve body 221 will decrease, and the effect of preventing wear on the sleeve 226 or the spool valve body 221 will not be sufficiently obtained.

[0089] In this embodiment, the inner circumferential surface of the sleeve 226, including the support portion 227 and the inclined portion 229, is entirely surface-treated with electroless nickel plating. In contrast, the spool valve body 221, which is inserted into the sleeve 226, has its entire outer circumferential surface treated with electrolytic plating (hard chromium plating).

[0090] The above embodiments are merely illustrative and do not limit the present invention in any way. Therefore, the present invention can naturally be improved and modified in various ways without departing from its essence. For example, although the above embodiments describe an example in which the spool valve 21 is used in a semiconductor manufacturing apparatus 1000, it may also be used in applications other than the semiconductor manufacturing apparatus 1000. [Explanation of Symbols]

[0091] 21 Spool valve 26A Input Ports 26B Input Ports 26C Input Ports 27A output port 27B Output Port 27C output port 29. First Surface Treatment Process 221 Spool valve body 222 Sleeves

Claims

1. comprising a cylindrical sleeve, The sleeve is provided with two or more input ports and two or more output ports that communicate with the inside of the sleeve. The spool valve body slides within the sleeve along the axial direction of the sleeve, In a spool valve in which the opening area of ​​the input port and the output port is adjusted by the sliding of the spool valve body, At least one of the sleeve and the spool valve body is provided with a support portion at both axial ends of the sleeve that reduces the gap between the inner circumferential surface of the sleeve and the outer circumferential surface of the spool valve body compared to other portions, thereby supporting the sliding motion of the spool valve body. The sleeve is provided with a first surface treatment area formed by a first plating at both ends in the axial direction of its inner circumferential surface. The first surface treatment portion is the support portion. A spool valve characterized by the following.

2. comprising a cylindrical sleeve, The sleeve is provided with two or more input ports and two or more output ports that communicate with the inside of the sleeve. The spool valve body slides within the sleeve along the axial direction of the sleeve, In a spool valve in which the opening area of ​​the input port and the output port is adjusted by the sliding of the spool valve body, At least one of the sleeve and the spool valve body is provided with a support portion at both axial ends of the sleeve that reduces the gap between the inner circumferential surface of the sleeve and the outer circumferential surface of the spool valve body compared to other portions, thereby supporting the sliding motion of the spool valve body. The spool valve body is provided with a surface treatment by electroplating on the outer circumferential surface, specifically on the portion of the outer circumferential surface of the sleeve that faces both ends in the axial direction. The surface treatment portion is the support portion. A spool valve characterized by the following.

3. In the spool valve according to claim 1, The axial width of the support portion is 1 mm or more, and 15% or less of the total axial length of the sleeve. A spool valve characterized by the following.

4. In the spool valve according to claim 1, The spool valve body is provided with a second surface treatment by plating on at least the portion of its outer circumferential surface facing the first surface treatment. The hardness of the second plating is higher than the hardness of the first plating. A spool valve characterized by the following.

5. In the spool valve according to claim 4, The first plating is electroless plating. The plating in the second instance is electrolytic plating. A spool valve characterized by the following.

6. comprising a cylindrical sleeve, The sleeve is provided with two or more input ports and two or more output ports that communicate with the inside of the sleeve. The spool valve body slides within the sleeve along the axial direction of the sleeve, In a spool valve in which the opening area of ​​the input port and the output port is adjusted by the sliding of the spool valve body, At least one of the sleeve and the spool valve body is provided with a support portion at both axial ends of the sleeve that reduces the gap between the inner circumferential surface of the sleeve and the outer circumferential surface of the spool valve body compared to other portions, thereby supporting the sliding motion of the spool valve body. The aforementioned spool valve is In a temperature control flow rate control unit for adjusting the temperature of a susceptor by circulating a temperature-controlling fluid through the susceptor of a semiconductor manufacturing apparatus, The flow rate of the low-temperature fluid used to lower the temperature of the temperature-controlled fluid, which is input to the first input port of the two or more input ports, and the flow rate output from the first output port of the two or more output ports, The flow rate of the high-temperature fluid used to raise the temperature of the temperature-controlled fluid, which is input to the second input port of the two or more input ports, and the flow rate output from the second output port of the two or more output ports, By adjusting the temperature of the temperature-controlled fluid, The gap, excluding the portion reduced by the support, is 7 μm or more. It must be less than or equal to μm. A spool valve characterized by the following.

7. comprising a cylindrical sleeve, The sleeve is provided with two or more input ports and two or more output ports that communicate with the inside of the sleeve. The spool valve body slides within the sleeve along the axial direction of the sleeve, In a spool valve in which the opening area of ​​the input port and the output port is adjusted by the sliding of the spool valve body, At least one of the sleeve and the spool valve body is provided with a support portion at both axial ends of the sleeve that reduces the gap between the inner circumferential surface of the sleeve and the outer circumferential surface of the spool valve body compared to other portions, thereby supporting the sliding motion of the spool valve body. The sleeve is provided with the support portion formed at both axial ends of its inner circumferential surface by reducing its inner diameter. The reduction in diameter of the support portion shall be 4 μm or more and 60 μm or less. A spool valve characterized by the following.

8. In the spool valve according to claim 7, The axial width of the support portion is 2% or more and 15% or less of the total axial length of the sleeve. A spool valve characterized by the following.

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