Substrate processing device, gas supply device, and design method

Abstract

A substrate processing device includes: a processing container in which a substrate can be accommodated in an internal space; a gas line connected to the processing container and capable of supplying a gas to the processing container; and an ON / OFF valve which is disposed at a location along the gas line that is the location closest to the processing container, and which opens and closs a flow path of the gas line. The gas line includes: an upstream pipe connected to the upstream side of the ON / OFF valve; and a downstream pipe connected to the downstream side of the ON / OFF valve. A valve-side Cv value indicating the ease of gas flow in the ON / OFF valve is at least a pipe-side Cv value indicating the ease of gas flow in the upstream pipe and the downstream pipe.

Description

Substrate processing apparatus, gas supply apparatus, and design method

[0001] This disclosure relates to a substrate processing apparatus, a gas supply apparatus, and a design method.

[0002] Patent Document 1 discloses a substrate processing apparatus in which an on / off valve is installed between a buffer tank and a processing vessel, and by switching this on / off valve on or off, gas from the buffer tank is supplied to the processing vessel to perform substrate processing such as film deposition. In this type of substrate processing apparatus, the amount of gas supplied to the processing vessel may vary depending on the configuration downstream of the buffer tank, including the on / off valve. Variations in the amount of gas supplied may affect the substrate processing inside the processing vessel.

[0003] Japanese Patent Publication No. 2022-158087

[0004] This disclosure provides a technology that can reduce variability in gas supply.

[0005] According to one aspect of the present disclosure, a substrate processing apparatus is provided, comprising: a processing container capable of housing a substrate in an internal space; a gas line connected to the processing container and capable of supplying gas to the processing container; and an on / off valve provided at a position in the gas line closest to the processing container and for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe connected upstream of the on / off valve and a downstream pipe connected downstream of the on / off valve, and the valve-side Cv value indicating the ease of gas flow at the on / off valve is equal to or greater than the pipe-side Cv value indicating the ease of gas flow at the upstream pipe and the downstream pipe.

[0006] According to one embodiment, variations in the amount of gas supplied can be reduced.

[0007] This figure schematically shows the overall configuration of the substrate processing apparatus according to the embodiment. This figure schematically shows the configuration of the on / off valve and its surrounding parts. This table shows the relationship between the total Cv value when the Cv value on the valve side of the on / off valve is changed while keeping the pipe-side Cv value of the upstream and downstream piping constant. This graph shows the relationship between the valve-side Cv value of the on / off valve and the total Cv value. This graph shows the change in pressure of the processing vessel with respect to time. This is an enlarged view of the IVB area in Figure 4A. This is an enlarged view of the IVC area in Figure 4A. This graph shows the relationship between the Cv value of the on / off valve and the total Cv value, and the relationship between the increase or decrease in the error amount of the total Cv value. This graph shows the relationship between the Cv value of the on / off valve and the pressure of the processing space in the processing vessel. This is a flowchart showing the design method of the gas supply device.

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] [Substrate Processing Apparatus] Figure 1 is a schematic diagram showing the overall configuration of the substrate processing apparatus 1 according to the embodiment. As shown in Figure 1, the substrate processing apparatus 1 according to the embodiment is an apparatus that includes a processing container 10 for housing a substrate W and performs substrate processing on the housing substrate W. Examples of substrates W to be processed include semiconductor substrates such as silicon wafers or compound semiconductor wafers. Examples of substrate processing include film deposition processing, in which a film is formed on the substrate W by chemical vapor deposition (CVD), atomic layer deposition (ALD), molecular layer deposition (MLD), etc. The following will explain using the substrate processing apparatus 1 that performs this film deposition processing as an example. Note that the substrate processing performed by the substrate processing apparatus 1 is not limited to film deposition processing, but may also include etching processing, modification processing, cleaning processing, ashing processing, etc.

[0010] Specifically, the substrate processing apparatus 1 includes, in addition to the processing container 10 described above, a substrate support section 20, a shower head 30, a gas exhaust section 40, and a gas supply device 50. Furthermore, the substrate processing apparatus 1 includes a control unit 90 that controls each component to perform substrate processing.

[0011] The processing container 10 is the target to which the gas is supplied and has an internal space 10s for containing and processing the substrate W. For example, the processing container 10 includes a concave container body 11 with a cylindrical side wall and a circular bottom wall that are continuous, and a lid 12 that covers the upper open portion of the container body 11. This processing container 10 is made of a metallic material such as aluminum or an aluminum alloy. However, the processing container 10 is not limited to this, and may be made of a highly heat-resistant material such as stainless steel, a low thermal expansion metal, a low thermal expansion alloy, or a low thermal expansion ceramic. In addition, the container body 11 may be equipped with a heating element (not shown) inside or around it to heat the processing container 10.

[0012] The container body 11 is provided with an inlet / outlet 13 on its side wall for loading and unloading substrates W. The inlet / outlet 13 is opened and closed by a gate valve 14. The substrate processing apparatus 1 is also equipped with a pressure sensor 15 for measuring the pressure in the internal space 10s (processing space PS) between the substrate W and the shower head 30. Furthermore, an exhaust duct 41 for the gas exhaust section 40 is provided between the container body 11 and the lid 12. The container body 11, the lid 12 and the exhaust duct 41 are fixed in a state of airtight sealing by a sealing member (not shown).

[0013] The substrate support section 20 supports the substrate W housed in the internal space 10s of the processing container 10. The substrate support section 20 includes a mounting table 21 on which the substrate W is placed, a support member 22 connected to the mounting table 21, and an operating mechanism 23 for operating the support member 22 outside the processing container 10.

[0014] The mounting table 21 is made of a metal material such as aluminum or nickel and is supported by a support member 22 within the processing container 10. In plan view, the mounting table 21 is formed in a perfect circle that is slightly larger than the substrate W. The mounting table 21 has a mounting surface 21s on its upper surface that horizontally supports the substrate W. The mounting table 21 may also be equipped with fixing means (not shown) for fixing the substrate W placed on the mounting surface 21s. Examples of fixing means include electrostatic adsorption, suction adsorption, and mechanical mechanisms.

[0015] Furthermore, the mounting table 21 may include an internal temperature control unit 21a for adjusting the temperature of the substrate W placed on the mounting surface 21s. For example, the temperature control unit 21a is configured by combining a flow path for a temperature control medium and a heater, and adjusts the temperature of the substrate W based on the control of the control unit 90. The mounting table 21 may also include an internal temperature sensor (not shown). The control unit 90 can adjust the temperature of the substrate W by feeding back the temperature of the substrate W measured by the temperature sensor during substrate processing.

[0016] The support member 22 is connected to the center of the bottom surface of the mounting base 21. The support member 22 extends downward to the processing container 10 through a hole formed in the bottom wall of the container body 11, and its lower end is connected to the operating mechanism 23. A flange portion 25 that can be displaced integrally with the support member 22 is attached to the support member 22, and a bellows 26 is provided between the bottom wall of the container body 11 and the flange portion 25. The bellows 26 expands and contracts in accordance with the displacement of the flange portion 25, thereby separating the internal space 10s of the processing container 10 from the outside.

[0017] The operating mechanism 23 raises and lowers and rotates the mounting table 21 via the support member 22 based on the control of the control unit 90. For example, the operating mechanism 23 raises and lowers the mounting table 21 between a processing position and a transport position. The processing position is the position where the substrate W is brought close to the shower head 30 and substrate processing is performed on the substrate W. The transport position is located vertically below the processing position and is the position where the substrate W is received and transferred. The operating mechanism 23 may also rotate the mounting table 21 placed at the processing position during substrate processing.

[0018] Furthermore, the substrate support section 20 has a lift pin lifting mechanism that raises and lowers a plurality of lift pins (not shown). The lift pin lifting mechanism is controlled by the control unit 90 when the mounting table 21 is positioned in the transport position by the operating mechanism 23. As a result, the substrate support section 20 receives and transfers substrates W to and from a transport device (not shown) that moves back and forth through the loading / unloading port 13.

[0019] The shower head 30 discharges processing gas into the internal space 10s of the processing container 10 (the processing space PS between the substrate W and the shower head 30). The shower head 30 is formed in a disc shape that can face the substrate W and is fixed to the upper vertical side of the processing container 10 (above the mounting base 21). The shower head 30 is constructed by stacking multiple members (for example, an upper member 31 and a lower member 32).

[0020] The shower head 30 is equipped with a gas diffusion chamber 33 at the boundary between the upper member 31 and the lower member 32. The lower member 32 of the shower head 30 also has a plurality of discharge holes 35 for discharging gas from the gas diffusion chamber 33 into the processing space PS. When gas is supplied from a gas supply device 50 located outside the processing container 10, the shower head 30 diffuses the gas horizontally in the gas diffusion chamber 33 and discharges the gas from the plurality of discharge holes 35 onto the opposing substrate W.

[0021] On the other hand, the gas exhaust unit 40 exhausts the gas from the internal space 10s of the processing container 10, creating a vacuum atmosphere inside the processing container 10 by reducing the pressure. The gas exhaust unit 40 includes an exhaust duct 41 provided in the processing container 10, and an exhaust path 42 and exhaust unit 43 provided outside the processing container 10.

[0022] The exhaust duct 41 is formed in an annular shape in plan view and encircles the upper part of the container body 11. The exhaust duct 41 has a slit 41a on its inner surface and an exhaust port 41b at an appropriate position on its outer surface. An exhaust path 42 is connected to the exhaust port 41b. The exhaust unit 43 is provided at an intermediate position in the exhaust path 42 and sucks gas from the processing container 10 based on the control of the control unit 90. This exhaust unit 43 is composed of an automatic pressure control (APC) valve, a vacuum pump, and the like.

[0023] The control unit 90 of the substrate processing apparatus 1 is a computer having a processor, memory, an input / output interface (not shown), and a communication interface. The processor is a combination of one or more of the following: CPU (Central Processing Unit), GPU (Graphics Processing Unit), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), a circuit consisting of multiple discrete semiconductors, etc. The memory includes main memory and auxiliary memory. In other words, in this disclosure, the control unit is an electronic circuit having a CPU, GPU, ASIC, FPGA, etc., and performs various control operations described in this specification by executing instruction codes stored in memory or by circuit design for special applications.

[0024] [Gas Supply Device] The gas supply device 50 is a device that supplies multiple types of gases used in the film formation process to the shower head 30 and discharges the gas from the shower head 30 into the processing space PS. The gas supply device 50 is connected to the control unit 90 and switches the supply of each gas based on the control of the control unit 90. The gas supply device 50 has, for example, a raw material gas supply unit 51, a first purge gas supply unit 52, a reaction gas supply unit 53, and a second purge gas supply unit 54. In this embodiment, TiCl is used as the raw material gas. ４ A gas is supplied, and NH is used as the reaction gas, which is a nitride gas. ３ An example of depositing a TiN film on a substrate W by supplying gas will be described. However, the substrate processing apparatus 1 is not limited to this and may supply various raw material gases and reaction gases.

[0025] The raw material gas supply unit 51 includes a raw material gas source 51a, a raw material gas line 51b, a primary valve 51c, a buffer tank 51d, a secondary valve 51e, and a flow rate controller 51f. The raw material gas source 51a supplies titanium chloride (TiCl), an example of a raw material gas, via the raw material gas line 51b. ４ ) To supply gas.

[0026] In the raw material gas line 51b, a flow rate controller 51f, a primary side valve 51c, a buffer tank 51d, and a secondary side valve 51e are provided in order from the raw material gas source 51a side. For example, a mass flow controller can be applied to the flow rate controller 51f. The buffer tank 51d temporarily stores TiCl ４ gas. A pressure gauge 51g is provided in the buffer tank 51d to measure the pressure of the stored gas. The primary side valve 51c stores TiCl ４ gas in the buffer tank 51d in an open state. The secondary side valve 51e is an on-off valve 60 applied as an ALD valve that supplies gas at high speed and intermittently in the film formation process. The opening and closing operations of the primary side valve 51c and the secondary side valve 51e are executed via a driver 69 (see FIG. 2) provided for each valve based on a control command from the control unit 90.

[0027] For example, in the supply of TiCl ４ gas, the raw material gas supply unit 51 stores TiCl ４ gas in the buffer tank 51d. At this time, the secondary side valve 51e is closed and the primary side valve 51c is opened. As a result, TiCl ４ gas is introduced into the buffer tank 51d until the target pressure is reached. When the target pressure is reached, the raw material gas supply unit 51 closes the primary side valve 51c while opening the secondary side valve 51e. As a result, TiCl ４ gas in the buffer tank 51d is supplied to the processing space PS of the processing container 10. After the supply, the secondary side valve 51e is closed and the primary side valve 51c is opened again to store TiCl ４ gas in the buffer tank 51d. The raw material gas supply unit 51 repeats this operation to supply TiCl ４ gas to the processing container 10 during the film formation process. Thus, the gas supply device 50 can supply TiCl ４ gas at high pressure by using the buffer tank 51d.

[0028] The first purge gas supply unit 52 includes a first purge gas source 52a, a first purge gas line 52b, a primary valve 52c, a buffer tank 52d, a secondary valve 52e, and a flow controller 52f. The first purge gas source 52a supplies nitrogen (N ２ ), an example of purge gas, through the first purge gas line 52b. This first purge gas line 52b is connected to the raw material gas line 51b. The purge gas may be an inert gas other than nitrogen gas.

[0029] In the first purge gas line 52b, a flow controller 52f, a primary valve 52c, a buffer tank 52d, and a secondary valve 52e are provided in this order from the first purge gas source 52a side. Also, a pressure gauge 52g is provided in the buffer tank 52d. Each device of the first purge gas supply unit 52 is configured in the same manner as each device of the raw material gas supply unit 51.

[0030] The reaction gas supply unit 53 includes a reaction gas source 53a, a reaction gas line 53b, a primary valve 53c, a buffer tank 53d, a secondary valve 53e, and a flow controller 53f. The reaction gas source 53a supplies ammonia (NH ３ ), an example of reaction gas, through the reaction gas line 53b.

[0031] In the reaction gas line 53b, a flow controller 53f, a primary valve 53c, a buffer tank 53d, and a secondary valve 53e are interposed in this order from the reaction gas source 53a side. Also, a pressure gauge 53g is provided in the buffer tank 53d. Each device of the reaction gas supply unit 53 is also configured in the same manner as each device of the raw material gas supply unit 51.

[0032] The second purge gas supply unit 54 includes a second purge gas source 54a, a second purge gas line 54b, a primary valve 54c, a buffer tank 54d, a secondary valve 54e, and a flow controller 54f. The second purge gas source 54a supplies nitrogen (N ２ ), an example of purge gas, through the second purge gas line 54b. This second purge gas line 54b is connected to the reaction gas line 53b.

[0033] In the second purge gas line 54b, a flow rate controller 54f, a primary side valve 54c, a buffer tank 54d, and a secondary side valve 54e are provided in this order from the second purge gas source 54a side. A pressure gauge 54g is provided in the buffer tank 54d. Each device of the second purge gas supply unit 54 is also configured in the same manner as each device of the raw material gas supply unit 51.

[0034] Next, the on-off valve 60 which is the secondary side valves 51e, 52e, 53e, 54e of the gas supply device 50 and the configuration of its peripheral portion will be described while referring to FIG. 2. FIG. 2 is a diagram schematically showing the configuration of the on-off valve and its peripheral portion. The on-off valve 60 can apply, for example, a valve with a float valve structure. This on-off valve 60 includes a valve housing 61, and has an inflow side flow path 61a and an outflow side flow path 61b inside this valve housing 61.

[0035] The valve housing 61 has a main body portion 611 formed in a rectangular shape or a cylindrical shape, and an inflow port 612 and an outflow port 613 that protrude in opposite directions from the main body portion 611. An upstream pipe 71 which is a part of each corresponding gas line (raw material gas line 51b, first purge gas line 52b, reaction gas line 53b, second purge gas line 54b) is connected to the inflow port 612. A downstream pipe 72 which is a part of each corresponding gas line is connected to the outflow port 613.

[0036] The upstream pipe 71 has a connector that can be screwed into the inflow port 612, and in the connection state with the on-off valve 60, the internal flow path communicates with the inflow side flow path 61a in the valve housing 61. The downstream pipe 72 also has a connector that can be screwed into the outflow port 613, and in the connection state with the on-off valve 60, the internal flow path communicates with the outflow side flow path 61b in the valve housing 61.

[0037] The inflow side flow path 61a extends in the horizontal direction (first direction) inside the main body portion 611 from the inflow port 612, bends at the axis of the valve housing 61, and extends in the vertical direction (second direction) perpendicular thereto. Further, the inflow side flow path 61a communicates with a valve space 61s provided inside the main body portion 611 at one end on the upper side in the vertical direction.

[0038] The outflow channel 61b communicates with the valve space 61s at a position adjacent to the inflow channel 61a. This outflow channel 61b extends longitudinally within the valve housing 61, bends, and extends in the opposite direction to the inflow channel 61a (parallel to the first direction) to reach the outflow port 613.

[0039] Furthermore, the inlet-side flow path 61a and outlet-side flow path 61b according to this embodiment do not have an orifice inside and form a straight flow path capable of circulating a large amount of fluid. The flow path diameters of the inlet-side flow path 61a and outlet-side flow path 61b are not particularly limited, but are preferably set to about 5 mm to 20 mm. By not having an orifice and having straight flow paths in the first and second directions, the on / off valve 60 can further increase the Cv value described later.

[0040] A diaphragm 62, which is the valve body, is provided in the valve space 61s, and a movable element 63 is provided to support the diaphragm 62 and to move the diaphragm 62 back and forth. Furthermore, a ring-shaped valve seat 65 is provided at the protruding end around the inflow side passage 61a facing the diaphragm 62. A resin with high sealing properties may be used for the valve seat 65. For example, a fluororesin such as PFA with high wear resistance can be used for the valve seat 65.

[0041] The diaphragm 62 moves back and forth relative to the valve seat 65 by the movable element 63, and seals the valve space 61s by contacting the valve seat 65. The on / off valve 60 becomes closed due to the contact between the diaphragm 62 and the valve seat 65. On the other hand, when the diaphragm 62 separates from the valve seat 65, the on / off valve 60 becomes open, with the inflow passage 61a, the valve space 61s, and the outflow passage 61b in communication.

[0042] The movable element 63 fixes the central part of the back side of the diaphragm 62. The movable element 63 is installed on an actuator 64 that moves up and down (second direction). The actuator 64 is connected to the control unit 90 via a driver 69, and moves the movable element 63 up and down based on the control of the control unit 90. A piezo valve using a piezoelectric element may be applied to this actuator 64. A piezo valve can operate the movable element 63 and the diaphragm 62 at high speed and is suitable for an ALD valve.

[0043] The Cv value of the on-off valve 60 described above is determined by the stroke of the diaphragm 62, the diameter of the inlet-side passage 61a and the outlet-side passage 61b, the length of the inlet-side passage 61a and the outlet-side passage 61b, etc. The Cv value of the on-off valve 60 is a capacity coefficient that indicates the ease of fluid flow, and is a value that represents the capacity of the valve when the diaphragm 62 is fully open. The larger the Cv value, the greater the fluid flow rate. Hereafter, the Cv value of the on-off valve 60 will also be referred to as the valve-side Cv value.

[0044] The on-off valve 60 according to this embodiment can maximize the valve-side Cv value through the configuration of the above-described pull valve structure. For example, an on-off valve 60 with a valve-side Cv value of 1.3 or higher can be used. However, the amount and pressure of gas supplied to the processing container 10 are not determined solely by the valve-side Cv values ​​of the secondary valves 51e, 52e, 53e, and 54e of the gas supply device 50. The amount and pressure of gas supplied to the processing container 10 depend on the total Cv value (hereinafter also referred to as the total Cv value) of the upstream piping 71, on-off valve 60, and downstream piping 72 located downstream of the buffer tanks 51d, 52d, 53d, and 54d.

[0045] The following will provide a detailed explanation of the total Cv values ​​downstream of buffer tanks 51d, 52d, 53d, and 54d. It is known that the Cv values ​​of the piping (upstream piping 71 and downstream piping 72) can be derived from the effective cross-sectional area of ​​the flow path of each pipe. Hereafter, the Cv values ​​of the piping will also be referred to as the piping-side Cv values. Here, if the effective cross-sectional area of ​​the piping is S, the following relationship (1) holds true for the piping-side Cv values.

[0046]

[0047] Furthermore, the effective cross-sectional area S of the pipe can be calculated by the following formula (2), where d [mm] is the inner diameter of the pipe, L [mm] is the length of the pipe, and λ is the coefficient of friction inside the pipe.

[0048]

[0049] Therefore, from equations (1) and (2), the Cv value on the piping side can be expressed by the following equation (3).

[0050]

[0051] For example, if the inner diameter d of the piping (upstream piping 71, downstream piping 72) is 7 mm and the length L of the piping is 500 mm, substituting these values ​​into equation (2) gives an effective cross-sectional area S of 24.70 [mm²]. ２ The following can be calculated. Note that the friction coefficient λ is set to 0.02 because the fluid flowing through the pipe is gas. Substituting the above value into equation (3), a Cv value of 1.34 can be calculated for the pipe.

[0052] Here, the upstream piping 71, the on / off valve 60, and the downstream piping 72, which are located downstream of the buffer tanks 51d, 52d, 53d, and 54d, are connected in series with each other (see also Figure 1). Therefore, if the Cv value of the upstream piping 71 is Cv1, the Cv value of the downstream piping 72 is Cv2, the valve-side Cv value of the on / off valve 60 is Cv, and the total Cv value is C, then the total Cv value (=C) can be calculated by the following equation (4) based on the formula for calculating the combined effective cross-sectional area when the piping is connected in series.

[0053]

[0054] Referring to equation (4) above, it can be seen that by increasing the valve-side Cv value of the on / off valve 60 relative to Cv1 of the upstream piping 71 and Cv2 of the downstream piping 72, the change in the total Cv value (=C) becomes smaller. In equation (4), 1 / C can be said to represent the combined conductance in the flow path downstream of buffer tanks 51d, 52d, 53d, and 54d.

[0055] Furthermore, the relationship between the gas flow rate Q and the Cv value in the flow channels downstream of buffer tanks 51d, 52d, 53d, and 54d can be expressed by the following equation (5) when the gas density and temperature are constant under critical expansion conditions.

[0056] Here, α is a constant that includes temperature and gas density, and P is the primary pressure of the gas.

[0057] As can be seen from equation (5), the gas flow rate Q is proportional to the Cv value. Therefore, the smaller the error in the Cv value, the smaller the error in the gas flow rate Q will be. In other words, from the relationship between equations (4) and (5), it can be seen that the errors in the amount and pressure of gas supplied to the processing container 10 can be reduced by increasing the valve-side Cv value of the on / off valve 60.

[0058] Figure 3A is a table showing the relationship between the total Cv value (=C) and the value of the valve side of the on-off valve 60 when the pipe side Cv value of the upstream piping 71 and downstream piping 72 is kept constant and the valve side Cv value of the on-off valve 60 is changed. Figure 3B is a graph showing the relationship between the valve side Cv value of the on-off valve 60 and the total Cv value. Figures 3A and 3B are the results of a simulation of the total Cv value when considering the error in the valve side Cv value. In the simulation, the value of 1.34 is applied to Cv1 of the upstream piping 71 and Cv2 of the downstream piping 72 as described above. The valve side Cv value of the on-off valve 60 is divided into two patterns: one using 0.6 as the base and applying values ​​of 0.54 and 0.66, which are ±10% of that value, and another using 2.3 as the base and applying values ​​of 2.07 and 2.53, which are ±10% of that value. This ±10% is the upper and lower limits of the allowable error range in the on-off valve 60's shipment inspection.

[0059] When the valve-side Cv value is 0.54, the total Cv value is 0.299. When the valve-side Cv value is 0.6, the total Cv value is 0.317. When the valve-side Cv value is 0.66, the total Cv value is 0.332. Using the total Cv value for a valve-side Cv value of 0.6 (0.317) as a baseline, the variations in the other total Cv values ​​are 6% and 4.8%.

[0060] On the other hand, when the valve-side Cv value is 2.07, the total Cv value is 0.506. When the valve-side Cv value is 2.3, the total Cv value is 0.519. When the valve-side Cv value is 2.53, the total Cv value is 0.530. Using the total Cv value (0.519) when the valve-side Cv value is 2.3 as a baseline, the variations in the other total Cv values ​​are 3% and 2.1%.

[0061] In other words, as can be seen from Figures 3A and 3B, when the valve-side Cv value of the on-off valve 60 is small (Cv = 0.6), the error range of the total Cv value is large. On the other hand, when the valve-side Cv value of the on-off valve 60 is large (Cv = 2.3), the error range of the total Cv value is small.

[0062] Thus, it can be seen that increasing the valve-side Cv value of the on-off valve 60 reduces the error (variation in Cv value) in the total Cv value. For example, when an on-off valve 60 with a valve-side Cv value of 2.3 is applied, it is possible to reduce the variation in error to approximately half compared to when an on-off valve 60 with a valve-side Cv value of 0.6 is applied.

[0063] Furthermore, in order to confirm the effect of increasing the valve-side Cv value of the on-off valve 60, a simulation was performed on the change in pressure in the processing container 10 (internal space 10s) when the valve-side Cv value of the on-off valve 60 was changed. The results are shown in Figures 4A to 4C. Figure 4A is a graph showing the change in pressure in the processing container 10 over time. Figure 4B is an enlarged view of the IVB area in Figure 4A. Figure 4C is an enlarged view of the IVC area in Figure 4A.

[0064] The pressure in the processing container 10 occurring at time t1 to t2 in Figure 4A shows the change with the secondary valve 51e (on-off valve 60) of the raw material gas supply unit 51 in the open state. Note that at time t1 to t2, the other secondary valves 52e, 53e, and 54e are in the closed state. Furthermore, the pressure in the processing container 10 occurring at time t3 to t4 in Figure 4A shows the change with the secondary valve 53e (on-off valve 60) of the reaction gas supply unit 53 in the open state. Note that at time t3 to t4, the other secondary valves 51e, 52e, and 54e are in the closed state.

[0065] The difference in pressure between time points t1-t2 and t3-t4 is due to the source gas (TiCl ４ ) supply amount and reaction gas (NH ３ This is because the supply amount differs from that of the gas supply device 50. In other words, the gas supply device 50 supplies a small amount of TiCl during substrate processing. ４ After supplying, a large amount of NH ３ The control system repeatedly performs the process of supplying the purge gas. Between time points t2 and t3, the first purge gas supply unit 52 supplies the purge gas, and between time points t1 and t4, the second purge gas supply unit 54 supplies the purge gas. During the period when the purge gas is supplied, the secondary valves 51e and 53e are switched to a closed state.

[0066] TiCl ４ When the fluid is supplied, the pressure in the internal space 10s of the processing container 10 rises slightly. It can also be seen that the pressure change in the processing container 10 differs depending on the valve-side Cv value of the on / off valve 60 (see Figure 4B). Specifically, when the valve-side Cv value is 0.6, the pressure peak in the processing container 10 is small, and the pressure change over time is gradual. On the other hand, when the valve-side Cv value is 2, the pressure peak in the processing space is large, and the pressure change over time is rapid.

[0067] Furthermore, when we refer to the valve-side Cv values ​​of 0.54 and 0.66, which are ±10% values ​​based on 0.6 as the baseline for the valve-side Cv value of the on-off valve 60, it can be seen that the pressure in the processing container 10 fluctuates significantly near the peak. In contrast, when we refer to the valve-side Cv values ​​of 1.8 and 2.2, which are ±10% values ​​based on 2 as the baseline for the valve-side Cv value of the on-off valve 60, it can be seen that the pressure in the processing container 10 fluctuates only slightly near the peak. In other words, a larger valve-side Cv value for the on-off valve 60 can suppress fluctuations in the pressure of the processing container 10.

[0068] Also, NH ３ When the supply is provided, the pressure in the processing container 10 rises significantly. In this case, it can be seen that the pressure change in the processing container 10 differs depending on the valve-side Cv value of the on-off valve 60 (see Figure 4C). Specifically, when the valve-side Cv value of the on-off valve 60 is 0.6, the pressure peak in the processing container 10 is small, and the pressure change over time is gradual. On the other hand, when the valve-side Cv value of the on-off valve 60 is 2, the pressure peak in the processing space is large, and the pressure change over time is rapid.

[0069] Furthermore, referring to the cases where the valve-side Cv value is 0.54, 0.6, and 0.66, NH ３ Even when supplied, it can be seen that the pressure in the processing container 10 fluctuates greatly near the peak. In contrast, referring to the cases where the valve-side Cv value is 1.8, 2, and 2.2, NH ３ Even when supplied, it can be seen that the pressure in the processing container 10 fluctuates slightly near its peak. In particular, NH ３ While supplying a large amount of gas increases the pressure in the processing container 10, a larger valve-side Cv value can be considered to suppress variations in the pressure of the processing container 10 more effectively. In other words, a larger gas supply amount has a greater effect in suppressing variations in errors caused by increasing the valve-side Cv value of the on / off valve 60.

[0070] Figure 5 is a graph showing the relationship between the valve-side Cv value and the total Cv value of the on / off valve 60, and the relationship between the increase or decrease in the error amount of the total Cv value. In Figure 5, examples are shown where three patterns of 0.666, 1.5, and 2.25 are applied as the piping-side Cv values.

[0071] As can be seen from Figure 5, the total Cv value follows the relationship: when the pipe-side Cv value is 0.666 < when the pipe-side Cv value is 1.5 < when the pipe-side Cv value is 2.25. Furthermore, when the pipe-side Cv value is 0.666, the total Cv value increases as the valve-side Cv value of the on-off valve 60 increases, but it can be said that it becomes roughly constant (rate-limiting) when the valve-side Cv value exceeds 5. Note that in Figure 5, the rate-limiting value is not observed for pipe-side Cv values ​​of 1.5 and 2.25, but it is thought that the rate-limiting value will similarly occur if the valve-side Cv value of the on-off valve 60 becomes even larger.

[0072] Furthermore, as shown in Figure 5, when the valve-side Cv value of the on / off valve 60 is equal to or greater than the pipe-side Cv value of the piping, the increase or decrease in the error amount of the total Cv value becomes less than zero. When the increase or decrease in the error amount of the total Cv value is less than zero, it is a state in which the calculation shows a negative value, and in reality, it can be said that there is almost no error. In other words, if the valve-side Cv value is the same as or greater than the pipe-side Cv value, it indicates that the error in the total Cv value will not increase. Therefore, in designing the valve-side Cv value of the on / off valves 60, which are secondary valves 51e, 52e, 53e, and 54e, it can be said that errors can be suppressed by making it equal to or greater than the pipe-side Cv value of the piping (upstream piping 71, downstream piping 72).

[0073] Furthermore, a detailed analysis of the graph reveals that when the pipe-side Cv value is 0.666, the increase or decrease in the error amount has an inflection point p1 where it begins to rise when the valve-side Cv value is around 1.3. Similarly, when the pipe-side Cv value is 1.5, the increase or decrease in the error amount has an inflection point p2 where it begins to rise when the valve-side Cv value is around 3. When the pipe-side Cv value is 2.25, the increase or decrease in the error amount has an inflection point p3 where it begins to rise when the valve-side Cv value is around 4.5. These inflection points can be considered turning points where the error in the total Cv value approaches zero. Therefore, it is preferable that the valve-side Cv value of the on / off valve 60 be set to twice or more the pipe-side Cv value. This is because when the valve-side Cv value is twice or more the pipe-side Cv value, the error in the total Cv value becomes smaller.

[0074] Figure 6 is a graph showing the relationship between the valve-side Cv value of the on / off valve 60 and the pressure in the processing space PS within the processing container 10. The processing space PS has a predetermined gap (GAP) between it and the shower head 30 when the substrate W is raised by the substrate support 20 and placed in the processing position. For example, this gap is set to a range of 0.5 mm to 3 mm. The graph in Figure 6 shows the results of confirming the dependence of the valve-side Cv value of the on / off valve 60 and the pressure in the processing space PS on differences in the gap and gas flow rate of the processing space PS.

[0075] In Figure 6, the white circles indicate NH with a high flow rate when the gap is 0.5 mm. ３ This is the pattern that supplied the material. The black circles indicate a large amount of NH when the gap is 3 mm. ３ This is the pattern in which the supply was performed. The white triangles indicate a low flow rate of TiCl with a gap of 0.5 mm. ４ This is the pattern in which the TiCl was supplied. The black triangles indicate a low flow rate with a gap of 3 mm. ４ This is the pattern that supplied it.

[0076] As shown in Figure 6, when the valve-side Cv value of the on / off valve 60 is in the range of 0.5 to 3, the pressure in the processing space PS increases as the valve-side Cv value increases. On the other hand, when the valve-side Cv value is greater than 3, the pressure in the processing space PS can be said to remain approximately constant. However, the largest change in the pressure of the processing space PS occurs when the flow rate is high with a gap of 0.5 mm NH ３ This is the pattern in which the pressure in the processing space PS increases when the valve-side Cv value increases from 0.5 to 1.5, for example. On the other hand, in the other patterns (black circle, white triangle, black triangle), when the valve-side Cv value increases from 0.5 to 1.5, for example, the pressure in the processing space PS increases when the valve-side Cv value increases from 0.5 to 1.5, for example, is approximately 1.3 times.

[0077] From the above, it can be said that when the gas flow rate is large and / or the gap of the processing space PS is small, the pressure in the processing space PS can be further increased by increasing the valve-side Cv value of the on-off valve 60. However, if the valve-side Cv value of the on-off valve 60 is greater than 3, the pressure in the processing space PS will remain approximately constant and the effect will not be improved. For this reason, if you want to keep the size of the on-off valve 60 down, it is best to select an on-off valve 60 with a valve-side Cv value of 3 or less.

[0078] [Summary] The design downstream of the buffer tanks 51d, 52d, 53d, and 54d, which include the above-mentioned on-off valves 60, can be summarized as follows (a) to (g). When designing the on-off valves 60, upstream piping 71, and downstream piping 72, it is advisable to consider these (a) to (g). (a) The valve-side Cv value should be set to be greater than or equal to the piping-side Cv value. (b) It is more preferable to set the valve-side Cv value to be at least twice the piping-side Cv value. (c) It is more preferable that the on-off valve 60 employs a pull-valve structure and does not have orifices in the inflow-side flow path 61a and the outflow-side flow path 61b. (d) The effect of increasing the valve-side Cv value is better when the gas flow rate is large. (e) The effect of increasing the valve-side Cv value is better when the gap of the processing space PS is narrow. (f) When the valve-side Cv value exceeds 3, the pressure of the processing space PS becomes approximately constant. (g) If the Cv value on the piping side is increased along with the Cv value on the valve side, the total Cv value will increase.

[0079] The substrate processing apparatus 1 and gas supply apparatus 50 according to this embodiment are basically configured as described above. The design method for the gas supply apparatus 50 (configuration downstream of buffer tanks 51d, 52d, 53d, and 54d) will be described below with reference to Figure 6.

[0080] In the design method for the configuration downstream of buffer tanks 51d, 52d, 53d, and 54d, first, the piping to be applied downstream of buffer tanks 51d, 52d, 53d, and 54d (upstream piping 71, downstream piping 72) is selected (step S101: process (A)). In selecting this piping, the size of the piping and the Cv value of the piping are taken into consideration. For example, as for the size of the piping, an appropriate size from the range of 3 / 8 inch to 1 / 2 inch is selected considering its application to the substrate processing apparatus 1.

[0081] On the other hand, as shown in equation (2), the Cv value of the piping is affected not only by the inner diameter of the piping but also by the length of the flow path, so it is best to set it appropriately according to the piping layout. One example of a piping-side Cv value is to set it to an appropriate value within the range of approximately 0.6 to 2. If the piping-side Cv value is less than 0.6, the gas supply amount will be greatly reduced, and the variation in error will increase. On the other hand, if the piping-side Cv value is greater than 2, it is expected that the piping will be thicker, making piping layout difficult.

[0082] Furthermore, after selecting the piping, the design method involves selecting an on-off valve 60 to be installed in the gas supply device 50 (step S102: process (B)). In selecting the on-off valve 60, it is preferable to set (select) the Cv value of the on-off valve 60 based on the Cv value of the piping selected earlier, as described above. That is, the Cv value of the on-off valve 60 is set to be equal to or greater than the Cv value of the piping. As a result, as described above, when the set on-off valve 60 supplies gas to the processing container 10 as it is opened and closed, variations in the gas flow rate can be suppressed, and consequently, the pressure in the processing container 10 can be suppressed. As a result, the substrate processing apparatus 1 can improve the accuracy of substrate processing, such as performing stable film deposition on the substrate W, and can also promote the efficiency of substrate processing.

[0083] It should be noted that the substrate processing apparatus 1, gas supply apparatus 50, and design method according to the embodiment are not limited to the above embodiment and can be modified in various ways. For example, the gas supply apparatus 50 may be applied to an apparatus other than the substrate processing apparatus 1 that has a gas to supply target. Also, the on / off valve 60 may be any type of valve as long as the Cv value is high, for example, a valve equipped with an orifice may be used.

[0084] [Technical Concept and Effects] The technical concept and effects of this disclosure, as described in the embodiments above, are described below.

[0085] A first aspect of the present disclosure is a substrate processing apparatus 1 comprising: a processing container 10 capable of housing a substrate W in an internal space 10s; a gas line (raw material gas line 51b, first purge gas line 52b, reaction gas line 53b, second purge gas line 54b) connected to the processing container 10 and capable of supplying gas to the processing container 10; and an on / off valve 60 provided at the position closest to the processing container 10 at an intermediate position in the gas line and opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe 71 connected upstream of the on / off valve 60 and a downstream pipe 72 connected downstream of the on / off valve 60, and the valve-side Cv value indicating the ease of gas flow at the on / off valve 60 is equal to or greater than the pipe-side Cv value indicating the ease of gas flow at the upstream pipe 71 and the downstream pipe 72.

[0086] As described above, the substrate processing apparatus 1 can reduce variations in the amount of gas supplied to the processing container 10 by ensuring that the valve-side Cv value of the on / off valve 60 is equal to or greater than the pipe-side Cv value of the piping (upstream piping 71 and downstream piping 72). In other words, the on / off valve 60, whose valve-side Cv value is equal to or greater than the pipe-side Cv value, can suppress errors in the gas flow rate due to fluctuations in the Cv value while allowing a large amount of gas to flow through in the open state. As a result, a stable amount of gas is supplied to the processing container 10. Consequently, the substrate processing apparatus can stably perform substrate processing on the substrate W contained in the processing container 10.

[0087] Furthermore, the Cv value on the valve side is more than twice the Cv value on the piping side. As a result, the substrate processing device 1 can increase the supply amount of gas flowing through the on / off valve 60, the upstream piping 71, and the downstream piping 72 while reducing the variation in the supply amount of said gas.

[0088] Furthermore, the valve-side Cv value is 3 or less. This allows the substrate processing apparatus 1 to suppress the increase in the size of the on / off valve 60 as the valve-side Cv value increases, and to easily install the on / off valve 60 in the peripheral area of ​​the substrate processing apparatus 1.

[0089] Furthermore, the upstream piping 71 is connected to buffer tanks 51d, 52d, 53d, and 54d, which store the gas supplied to the processing container 10. As a result, the substrate processing apparatus 1 can supply the high-pressure gas stored in the buffer tanks 51d, 52d, 53d, and 54d to the processing container 10 via the upstream piping 71, the on / off valve 60, and the downstream piping 72, enabling stable gas supply and gas switching during substrate processing.

[0090] Furthermore, the on / off valve 60 includes a valve body (diaphragm 62) and flow paths (inlet-side flow path 61a, outlet-side flow path 61b) that extend in a direction perpendicular or parallel to the surface of the valve body and do not have an orifice. This makes it possible to achieve a configuration in which the on / off valve 60 has a large valve-side Cv value while suppressing an increase in size.

[0091] Furthermore, the Cv value on the piping side is set within the range of 0.6 to 2. This allows the substrate processing device 1 to maximize the Cv values ​​on the piping side of the upstream piping 71 and the downstream piping 72, thereby increasing the amount of gas supplied to the processing container 10.

[0092] Furthermore, the sizes of the upstream piping 71 and the downstream piping 72 are set within the range of 3 / 8 to 1 / 2 inch. This allows the substrate processing device 1 to connect to the processing container 10 with appropriately sized piping while ensuring a sufficient supply of circulating gas.

[0093] Furthermore, a second aspect of this disclosure is a gas supply device 50 comprising a gas line (raw material gas line 51b, first purge gas line 52b, reaction gas line 53b, second purge gas line 54b) capable of supplying gas to a supply target (processing container 10), and an on / off valve 60 provided at the position closest to the supply target in the middle of the gas line for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe 71 connected upstream of the on / off valve 60 and a downstream pipe 72 connected downstream of the on / off valve 60, and the valve-side Cv value indicating the ease of gas flow at the on / off valve 60 is equal to or greater than the pipe-side Cv value indicating the ease of gas flow at the upstream pipe 71 and the downstream pipe 72. Even in this case, the gas supply device 50 can reduce variations in the amount of gas supplied to the supply target.

[0094] Furthermore, a third aspect of this disclosure is a design method for a gas supply device 50 comprising a gas line capable of supplying gas to a target (raw material gas line 51b, first purge gas line 52b, reaction gas line 53b, second purge gas line 54b), and an on / off valve 60 provided at the position closest to the target in the middle of the gas line for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe 71 connected upstream of the on / off valve 60 and a downstream pipe 72 connected downstream of the on / off valve 60, and the design method comprises (A) setting a pipe-side Cv value indicating the ease of gas flow in the upstream pipe 71 and the downstream pipe 72, and (B) after step (A), setting a valve-side Cv value indicating the ease of gas flow in the on / off valve 60 to be equal to or greater than the pipe-side Cv value. Even in this case, the design method can reduce variations in the amount of gas supplied to the target by the gas supply device 50.

[0095] The substrate processing apparatus 1, gas supply apparatus 50, and design method according to the embodiments disclosed herein are illustrative in all respects and are not restrictive. The embodiments can be modified and improved in various ways without departing from the scope and spirit of the appended claims. The matters described in the above embodiments can be otherwise configured and combined in a non-consistent manner.

[0096] This application claims priority to Japanese Patent Application No. 2024-190688, which was filed with the Japan Patent Office on October 30, 2024, and the entire contents of that application are incorporated herein by reference.

[0097] 1. Substrate processing device 10. Processing container 10s. Internal space 60. On / off valve 71. Upstream piping 72. Downstream piping W. Substrate

Claims

1. A substrate processing apparatus comprising: a processing container capable of housing a substrate in its internal space; a gas line connected to the processing container and capable of supplying gas to the processing container; and an on / off valve provided at the position closest to the processing container at an intermediate position in the gas line for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe connected upstream of the on / off valve and a downstream pipe connected downstream of the on / off valve, and the valve-side Cv value indicating the ease of gas flow at the on / off valve is equal to or greater than the pipe-side Cv value indicating the ease of gas flow at the upstream pipe and the downstream pipe.

2. The substrate processing apparatus according to claim 1, wherein the valve-side Cv value is twice or more the piping-side Cv value.

3. The substrate processing apparatus according to claim 1 or 2, wherein the valve-side Cv value is 3 or less.

4. The substrate processing apparatus according to claim 1 or 2, wherein the upstream piping is connected to a buffer tank for storing gas supplied to the processing vessel.

5. The substrate processing apparatus according to claim 1 or 2, wherein the on / off valve includes a valve body and a flow path extending in a direction perpendicular or parallel to the surface of the valve body and not having an orifice.

6. The substrate processing apparatus according to claim 1 or 2, wherein the Cv value on the piping side is set within the range of 0.6 to 2.

7. The substrate processing apparatus according to claim 1 or 2, wherein the size of the upstream piping and the downstream piping is set within the range of 3 / 8 to 1 / 2 inch.

8. A gas supply device comprising: a gas line capable of supplying gas to a target; and an on-off valve provided at the position closest to the target at an intermediate position in the gas line, for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe connected upstream of the on-off valve and a downstream pipe connected downstream of the on-off valve, and the valve-side Cv value indicating the ease of gas flow at the on-off valve is equal to or greater than the pipe-side Cv value indicating the ease of gas flow at the upstream pipe and the downstream pipe.

9. A design method for a gas supply device comprising: a gas line capable of supplying gas to a target; and an on-off valve provided at the position closest to the target at an intermediate position in the gas line for opening and closing the flow path of the gas line, wherein the gas line includes an upstream pipe connected upstream of the on-off valve and a downstream pipe connected downstream of the on-off valve, and the design method comprising: (A) setting a pipe-side Cv value indicating the ease of gas flow in the upstream pipe and the downstream pipe; and (B) after step (A), setting a valve-side Cv value indicating the ease of gas flow in the on-off valve to be equal to or greater than the pipe-side Cv value.

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