Valve assembly for controlling flow rate, flow rate control method, and substrate processing apparatus comprising same

Abstract

A valve assembly for controlling a flow rate, according to an embodiment, comprises: a gas inlet / outlet unit comprising an inlet flow path into which a substrate processing gas is introduced, an outlet flow path connected to a process chamber in which substrate processing is performed, to supply gas, and a valve compartment connecting the inlet flow path and the outlet flow path; a valve unit comprising a membrane valve installed above the inlet flow path, a pressurizing rod that pressurizes the membrane valve to adjust an aperture ratio of the inlet flow path and the flow rate of the gas, and a pneumatic control unit which controls the supply of valve control air to cause the pressurizing rod to ascend or descend, so as to control the flow rate of gas passing through the valve compartment; and a control unit which controls the operation of the gas inlet / outlet unit and the valve unit, wherein the control unit can control the operation of the pneumatic control unit such that the valve control air is supplied at a first supply pressure to open the membrane valve, and then, the valve control air is supplied at a second supply pressure lower than the first supply pressure, and the membrane valve is closed at the second supply pressure.

Description

Valve assembly for flow control, flow control method and substrate processing device including the same

[0001] The present invention relates to a valve assembly for flow control, a flow control method, and a substrate processing device including the same.

[0002] Recently, as the integration of semiconductor devices increases, precise control of substrate processing equipment is required.

[0003] Typically, semiconductor devices are manufactured by performing various substrate processing processes, such as thin film deposition and etching, in a vacuum-atmosphere substrate processing device. These substrate processing processes are performed by injecting process gases onto the substrate through a gas injector while the substrate is seated on a substrate support within a process chamber. During this process, the flow rate of the process gases supplied to perform the substrate processing process affects the deposition rate and uniformity of the thin film, among other characteristics.

[0004] The substrate processing device includes a process chamber in which substrate processing is performed, and a gas supply device for supplying process gas for substrate processing into the process chamber, wherein the gas supply device includes a vaporizer for vaporizing a raw material, a supply pipe connecting the vaporizer and the process chamber, and a plurality of flow control valves and sensors installed on the supply pipe for controlling the flow of fluid. In particular, the flow control valve utilizes a method in which one solenoid valve is installed, and the solenoid valve applies air pressure to a valve actuator to control the opening and closing operations of the valve.

[0005] However, since the flow control valve having the above structure utilizes a method of controlling the application of air pressure using a single solenoid valve, the valve actuator driven by air pressure exhibits the characteristic that the opening speed of the valve increases when the air pressure is high, but the closing speed is delayed. Conversely, the flow control valve exhibits the characteristic that the opening time of the valve is delayed and the closing speed is increased when the valve actuator driven by air pressure is low.

[0006] As described above, existing flow control valves have a problem in that high-speed opening and closing control is difficult due to delays in closing or opening time depending on pneumatic conditions. Therefore, research is needed on a method to supplement this problem.

[0007] According to one embodiment, the present invention provides technical content regarding a valve assembly for fluid flow control capable of high-speed opening and closing control and a fluid flow control method.

[0008] A valve assembly for controlling flow rate according to an embodiment comprises: a gas inlet / outlet section including an inlet passage through which a substrate processing gas is introduced, an outlet passage connected to a process chamber in which substrate processing is performed and supplying the gas, and a valve compartment connecting the inlet passage and the outlet passage; a valve section for controlling the flow rate of the gas passing through the valve compartment, including a membrane valve installed on an upper portion of the inlet passage, a pressurizing rod for pressurizing the membrane valve to control an opening ratio of the inlet passage and a flow rate of the gas, and a pneumatic control unit for controlling the supply of valve control air for driving the pressurizing rod up and down; and a control section for controlling the operation of the valve section; wherein the control section can control the operation of the pneumatic control unit to open the membrane valve by supplying the valve control air at a first supply pressure, then supplying the valve control air at a second supply pressure lower than the first supply pressure, and close the membrane valve at the second supply pressure.

[0009] According to one embodiment, the valve part may include a valve body having an accommodation space formed therein and having at least one air supply pipe connected to one side thereof so that the valve control air flows in and out; and a piston that partitions the accommodation space of the valve body and moves up and down along an inner wall surface of the valve body by the flow or inflow of the valve control air into one of the partitioned spaces to raise and lower the pressurizing rod. In addition, the valve part may include an elastic restoring member that is installed on one side of the piston and provides elastic force so that the pressurizing rod pressurizes the membrane valve to close the inflow path.

[0010] According to one embodiment, the valve unit includes a valve body to which a first air supply pipe and a second air supply pipe are connected; and an air pressure control unit having a first solenoid valve and a second solenoid valve installed in the first air supply pipe and the second air supply pipe, respectively; and the control unit controls the supply of the valve control air at the first supply pressure by opening the first solenoid valve and then opening the second solenoid valve and closing the first solenoid valve, and the first solenoid valve and the second solenoid valve may have different maximum supply pressures.

[0011] According to one embodiment, the pneumatic control unit may further include a detection sensor installed on one side of the first solenoid valve to check the open state of the first solenoid valve.

[0012] In one embodiment, the first solenoid valve may have a maximum supply pressure of 0.45 to 1 MPa, and the second solenoid valve may have a maximum supply pressure of 0.1 to less than 0.45 MPa. In particular, the first solenoid valve may have a maximum supply pressure of 0.6 MPa, and the second solenoid valve may have a maximum supply pressure of 0.3 MPa.

[0013] According to one embodiment, the valve unit includes a pneumatic control unit having a pneumatic variable solenoid valve installed in the air supply pipe; and the control unit controls the pneumatic variable solenoid valve to supply the valve control air at the first supply pressure by applying a first power to the pneumatic variable solenoid valve, and then to supply the valve control air at the second supply pressure by applying a second power having a lower current than the first power to the pneumatic variable solenoid valve, wherein the opening ratio of the pneumatic variable solenoid valve can be adjusted according to the current of the applied power. At this time, the first supply pressure may be 0.45 to 1 MPa, and the second supply pressure may be 0.1 to less than 0.45 MPa.

[0014] Meanwhile, a substrate processing device according to an embodiment may include a process chamber having a processing space formed therein for performing substrate processing; a substrate support unit installed inside the processing space and on which a substrate is placed; a gas injection unit for injecting gas into the processing space for substrate processing; a gas supply unit for supplying a process gas to the gas injection unit; and a flow control valve assembly according to any one of claims 1 to 9, which is installed between the gas supply unit and the gas injection unit and controls a flow rate of the gas.

[0015] According to one embodiment, a method for controlling flow rate using the valve assembly for controlling flow rate may include: receiving a gas supply signal, supplying valve control air at a first supply pressure to open the membrane valve to allow the flow of gas through a gas inlet / outlet port, thereby supplying gas to a process chamber; varying the supply of the valve control air at a second supply pressure lower than the first supply pressure, thereby maintaining the supply of the gas to the process chamber; and receiving a gas blocking signal, blocking the supply of the valve control air to block the flow of gas through the gas inlet / outlet port.

[0016] According to one embodiment, the step of supplying gas to the process chamber may further include the step of checking whether valve regulating air is supplied at the first supply pressure.

[0017] The valve assembly for flow control according to the embodiment opens the valve under supply pressure conditions favorable for opening upon initial pneumatic pressure application, varies the supply pressure to open the valve under supply pressure conditions favorable for closing, and then blocks the gas supply, thereby enabling high-speed opening and closing control. Accordingly, the flow rate of process gas can be precisely controlled, significantly improving the process stability of the substrate processing device.

[0018] Fig. 1 is a schematic diagram showing a substrate processing device according to an embodiment.

[0019] Figure 2 is a schematic diagram showing a valve assembly for flow control according to Example 1 in a state where gas flow is permitted.

[0020] Figure 3 is a schematic diagram showing a valve assembly for flow control according to Example 1 in a state where gas flow is blocked.

[0021] Fig. 4 is a schematic diagram showing a valve assembly for flow control according to Example 2 in a state where gas flow is permitted.

[0022] Fig. 5 is a schematic diagram showing a valve assembly for flow control according to Example 2 in a state where gas flow is blocked.

[0023] Figure 6 is a process diagram showing a flow control method according to an embodiment.

[0024] A valve assembly for controlling flow rate according to an embodiment comprises: a gas inlet / outlet section including an inlet passage through which a substrate processing gas is introduced, an outlet passage connected to a process chamber in which substrate processing is performed and supplying the gas, and a valve compartment connecting the inlet passage and the outlet passage; a valve section for controlling the flow rate of the gas passing through the valve compartment, including a membrane valve installed on an upper portion of the inlet passage, a pressurizing rod for pressurizing the membrane valve to control an opening ratio of the inlet passage and a flow rate of the gas, and a pneumatic control unit for controlling the supply of valve control air for driving the pressurizing rod up and down; and a control section for controlling the operation of the valve section; wherein the control section can control the operation of the pneumatic control unit to open the membrane valve by supplying the valve control air at a first supply pressure, then supplying the valve control air at a second supply pressure lower than the first supply pressure, and close the membrane valve at the second supply pressure.

[0025] Fig. 1 is a schematic diagram showing a substrate processing device according to an embodiment.

[0026] Referring to FIG. 1, a substrate processing device (1) according to an embodiment may include a valve assembly for flow control (10, 10`), a process chamber (20), a substrate support unit (30), a gas injection unit (40), and a gas supply unit (50).

[0027] The above process chamber (20) may have a processing space formed therein for processing a substrate (S). The process chamber (20) is configured to maintain airtightness by including a chamber body (21) and an upper lid (22) positioned at the upper end of the side wall of the chamber body (21). An exhaust port and a vacuum pump may be connected to the process chamber (20) to discharge process gas from the processing space and control the vacuum level of the processing space. The process chamber (20) may have various typical forms used for substrate processing.

[0028] The substrate support member (30) is installed inside the processing space of the process chamber (20) and may be formed so that the substrate (S) is seated within the processing space. The substrate support member (30) may be installed in the process chamber (20) so that the substrate (S) faces the gas injection member (40). The substrate support member (30) may include a susceptor or the like configured so that the substrate (S) is seated.

[0029] The above gas injection unit (40) is installed in the process chamber (20) facing the substrate support unit (30) and can inject process gas into the processing space. The gas injection unit (40) can have various shapes such as a shower head shape, a nozzle shape, etc., and when the gas injection unit (40) is in the shower head shape, the gas injection unit (40) can be coupled to the process chamber (20) in a shape that partially covers the upper portion of the process chamber (20). In particular, the gas injection unit (40) can be coupled to the upper lid (22) in the shape of a cover of the chamber body (21).

[0030] The above gas supply unit (50) is a device for supplying the process gas to the gas injection unit (40) and can be connected to the gas injection unit (40).

[0031] The above gas supply unit (50) can generate and supply process gas from a liquid source or a solid source. The flow rate of the process gas can be controlled through the flow rate control valve assembly (10, 10`) and supplied to the gas injection unit (40).

[0032] The substrate processing device (1) according to the embodiment may include a flow control valve assembly (10, 10`) installed on one side of a gas pipe (41) that is connected to a gas supply unit (50) and transports a process gas to control the flow rate of the process gas.

[0033] The valve assembly (10, 10`) for flow control according to the embodiment may be provided in an array structure on the gas injection unit (40) or may be installed together with general-purpose mass flow controllers (not shown) in a gas box (not shown).

[0034] The substrate processing device (1) according to the embodiment is capable of high-speed control of the flow rate supply through a valve assembly (10, 10`) for flow rate control. Accordingly, the substrate processing device (1) according to the embodiment can precisely control the flow rate of the process gas and supply it onto the substrate (S) through the gas injection unit (40). Therefore, the process stability through the substrate processing device (1) can be significantly improved.

[0035] The substrate processing device (1) according to the embodiment may be any one of a chemical vapor deposition (CVD) device, a plasma enhanced chemical vapor deposition (PECVD) device, and an atomic layer deposition (ALD) device.

[0036] Below, the valve assembly (10, 10`) for flow control according to the embodiment will be examined in more detail.

[0037] The valve assembly (10, 10`) for controlling the flow rate according to the embodiment is for controlling the flow rate of a fluid, for example, a gas used for substrate processing, and may be coupled to a fluid supply pipe. In addition, the valve assembly (10, 10`) for controlling the flow rate according to the embodiment may be configured within the vaporizer as a part of the vaporizer.

[0038] Specifically, the above-described valve assembly (10, 10`) for flow control can be used to control the flow rate of a fluid. For example, the valve assembly (10, 10`) for flow control can have a structure that controls the opening and closing of a membrane valve (250) by applying air pressure to control the flow rate of a fluid flowing into a process chamber (20).

[0039] Fig. 2 is a schematic diagram showing a valve assembly (10) for flow control according to embodiment 1 in a state where gas flow is permitted. Fig. 3 is a schematic diagram showing a valve assembly (10) for flow control according to embodiment 1 in a state where gas flow is blocked. Fig. 4 is a schematic diagram showing a valve assembly (10`) for flow control according to embodiment 2 in a state where gas flow is permitted. Fig. 5 is a schematic diagram showing a valve assembly (10`) for flow control according to embodiment 2 in a state where gas flow is blocked.

[0040] Referring to FIGS. 2 to 5, a valve assembly (10, 10`) for flow control according to an embodiment includes a gas inlet / outlet section (100), a valve section (200), and a control section (300).

[0041] The above gas inlet / outlet (100) serves to provide a passage for gas to flow and be distributed. To this end, the gas inlet / outlet (100) may have a structure including an inlet passage (110), an outlet passage (130), and a valve compartment (150).

[0042] The above inlet passage (110) provides a passage through which gas flows. The inlet passage (110) is connected at one end to a gas supply unit (50) and a gas pipe (41) so that gas can flow in. The inlet passage (110) may have an inlet hole (111) formed at the other end so that gas passing through the inlet hole (111) moves along the valve compartment (150) and is supplied to the process chamber (20) through the outlet passage (130). The inlet hole (111) may have a membrane valve (250) installed at the top so that opening and closing can be controlled. When the inlet hole (111) is opened, the gas can flow and flow into the outlet passage (130), and when the inlet hole (111) is closed, the flow of gas is blocked.

[0043] The above-mentioned outlet passage (130) is connected to a process chamber (20) where substrate processing is performed, and forms a passage for supplying gas flowing through the inlet passage (110) to the process chamber (20). The outlet passage (130) has an outlet hole (131) formed at the other end, and when the inlet hole (111) is opened, the gas can flow in. The gas may mean a vaporized gas, i.e., a process gas for substrate processing. The gas may be a single gas or a mixed gas.

[0044] The valve compartment (150) is formed between the inlet passage (110) and the outlet passage (130) to provide a space for connecting the inlet passage (110) and the outlet passage (130). The inlet hole (111) and the outlet hole (131) are respectively connected to the valve compartment (150). A membrane valve (250) for controlling the opening and closing of the inlet hole (111) may be installed in the valve compartment (150). The valve compartment (150) may have a structure in which a pressure rod for controlling the operation of the membrane valve (250) is installed at the upper portion to have a structure in which the pressure rod can be raised and lowered.

[0045] The above valve part (200) can adjust the opening ratio of the inlet hole (111) so as to control the flow rate of the gas passing through the gas inlet / outlet part (100). The above valve part (200) can adjust the opening ratio of the inlet hole (111) of the gas inlet / outlet part (100) according to the flow of valve control air.

[0046] To this end, the valve part (200) may have a structure including a valve body (210), a pressure rod (220), a piston (230), an elastic restoring member (240), a membrane valve (250), and a pneumatic control unit (260, 260`).

[0047] The valve body (210) has a receiving space formed therein so that valve control air can be introduced, and can accommodate a pressurized rod (220), a piston (230), an elastic restoring member (240), etc. The valve body (210) can be formed in a circular or polygonal container shape with the upper and lower parts closed.

[0048] The above valve body (210) can be connected to at least one air supply pipe (211, 213).

[0049] Referring to FIGS. 1 and 2, the flow control device (10) according to Example 1 can have multiple air supply pipes (211, 213) each connected to it.

[0050]

[0051] *The above plurality of air supply pipes (211, 213) are each connected to an internal passage (215) formed inside the receiving space of the valve body (210) to form a passage for supplying valve control air to the internal receiving space of the valve body (210).

[0052] For example, the valve body (210) may have a structure in which a first air supply pipe (211) and a second air supply pipe (213) are respectively connected to the upper portion. In the drawing, only a structure in which two air supply pipes (211, 213) are installed is illustrated, but the number of air supply pipes to be installed may be selectively adjusted as needed. When a plurality of air supply pipes (211, 213) are installed as described above, a plurality of solenoid valves (261, 263) having different maximum supply pressures may be installed as a pneumatic control unit (260) in each of the plurality of air supply pipes (211, 213).

[0053] Referring to FIGS. 3 and 4, the flow control device (10`) according to Example 2 may have a structure in which one air supply pipe (211) is connected to the valve body (210). An air pressure variable solenoid valve (265) may be installed as an air pressure control unit (260`) in the one air supply pipe (211).

[0054] In addition, the valve body (210) has an exhaust path (not shown) formed on one side so that the valve control air supplied inside the receiving space can be ejected to the outside.

[0055] The above-mentioned pressurizing rod (220) is partially accommodated in the accommodation space of the valve body (210), and one end is accommodated in the valve compartment (150). The pressurizing rod (220) is arranged above the membrane valve (250) installed in the valve compartment (150). The pressurizing rod (220) can pressurize the membrane valve (250) by being driven downward, and can control the opening and closing of the inlet hole (111) by being driven upward. The pressurizing rod (220) can have a variety of conventional structures having an elastic pressurizing tip formed at one end and utilized to pressurize the membrane valve (250).

[0056] The piston (230) divides the accommodation space of the valve body (210), and can drive the pressure rod (220) up and down by driving it up and down along the inner wall surface of the valve body (210) by supplying or ejecting valve control air to any one of the divided spaces. The pressure rod (220) can be connected to the central region of the piston (230) in a structure that can provide driving force.

[0057] The elastic restoring member (240) is accommodated in the accommodation space of the valve body (210) and is installed on one side of the piston (230) to assist in the raising and lowering of the piston (230). For example, the elastic restoring member (240) functions to restore the piston (230) to its original position when the piston (230) is raised and lowered by air pressure formed by air supply and then the air pressure is removed.

[0058] The above elastic restoring member (240) may be implemented as a coil spring that applies elastic force so that the pressure rod (220) presses the upper surface of the membrane valve (250) to close the inlet hole (111). In addition, the above elastic restoring member (240) may be elastically deformed to raise and lower the pressure rod by the operation of a solenoid to release the pressure on the membrane valve (250).

[0059] The above membrane valve (250) is accommodated inside the valve compartment (150) and installed above the inlet hole (111). The above membrane valve (250) is an elastic structure having a diaphragm shape and is called a sealing gasket, a diaphragm valve, an umbrella-type check valve, etc.

[0060] The above membrane valve (250) functions to open and close the inlet hole (111) by elastically deforming according to the operation of the pressurizing rod (220). In addition, the membrane valve (250) can control the flow rate of the fluid by adjusting the pressurizing condition of the pressurizing rod (220) to control the open area of ​​the inlet hole (111). When the height of the piston (230) that the membrane valve (250) is raised and lowered increases, the pressurizing pressure by the pressurizing rod (220) decreases, thereby expanding the open area of ​​the inlet hole (111).

[0061] The above-mentioned pneumatic control unit (260) can control the opening and closing of the membrane valve by controlling the supply of valve control air to the valve body (210). To this end, the above-mentioned pneumatic control unit (260) can have a structure including a solenoid valve (216, 263, 265) connected to the air supply pipe (211, 213).

[0062] The above solenoid valves (216, 263, 265) are controlled by an electric signal, and when power is applied, they open to supply high-pressure valve control air to the valve body (210) through the air supply pipe (211, 213). When power is cut off, the above solenoid valves (216, 263, 265) can close the air supply pipe (211, 213) to block the supply of valve control air.

[0063] In particular, in the valve assembly (10. 10`) for flow control according to the embodiment, the air pressure control unit (260, 260`) supplies air at a first supply pressure that is advantageous for opening when initial air pressure is applied to allow the flow of gas, and then controls the supply pressure to be varied so that air is supplied at a second supply pressure that is advantageous for closing, thereby improving the response speed of the valve assembly (10. 10`) for flow control.

[0064] Specifically, referring to FIGS. 1 and 2, in the valve assembly (10) for flow control according to Example 1, the pneumatic control unit (260) may have a structure including a plurality of solenoid valves (261, 263) having different maximum supply pressures.

[0065] The plurality of solenoid valves (261, 263) may be installed one by one in each of the plurality of air supply pipes (211, 213). The plurality of solenoid valves (261, 263) may have different maximum supply pressures. That is, the plurality of solenoid valves (261, 263) have different maximum flow path areas and different maximum supply pressures.

[0066] The valve assembly (10) for controlling the flow rate according to Example 1 may have a structure including a pneumatic control unit (260) equipped with a first solenoid valve (261) and a second solenoid valve (263). The plurality of solenoid valves (261, 263) are each controlled by an electric signal and can control the flow of fluid using the force of a magnetic field generated from the solenoids. The first and second solenoid valves (261, 263) may be installed one by one in the first and second air supply pipes (211, 213), respectively.

[0067] The first solenoid valve (261) may have a maximum supply pressure in the range of 0.45 to 1 MPa. The second solenoid valve (263) may have a maximum supply pressure in the range of less than 0.1 to 0.45 MPa, which is relatively low.

[0068] More specifically, the first solenoid valve (261) may have a maximum supply pressure of 0.45 to 0.6 MPa, and the second solenoid valve (263) may have a maximum supply pressure of 0.3 to less than 0.45 MPa. In particular, the first solenoid valve (261) may have a maximum supply pressure of 0.6 MPa, and the second solenoid valve (263) may have a maximum supply pressure of 0.3 MPa.

[0069] The above first solenoid valve (261) exhibits a characteristic in which the opening speed of the valve is fast, but the closing speed is delayed. The above second solenoid valve (263) exhibits a characteristic in which the opening time of the valve is delayed, and the closing speed is fast.

[0070] In addition, the air pressure control unit (260, 260`) may further include a detection sensor (267). The detection sensor (267) serves to check whether the solenoid valve (261, 263) is open or closed. When a fluid supply signal is transmitted, the detection sensor (267) checks whether the solenoid valve (261, 263) is open, and when the solenoid valve (261, 263) is confirmed to be closed, the detection sensor generates a detection signal and transmits it to the control unit (300), and the control unit (300) can regenerate a signal for opening the solenoid valve (261, 263) and transmit it to the solenoid valve (261, 263).

[0071] Referring to FIGS. 3 and 4, in the valve assembly (10`) for flow control according to Example 2, the pneumatic control unit (260`) may have a structure including a pneumatic variable valve that can vary the pneumatic pressure according to pressure conditions.

[0072] The above pneumatic variable solenoid valve (265) exhibits a characteristic in which the output supply pressure is controlled according to the amount of current applied to the solenoid.

[0073] The above pneumatic variable solenoid valve (265) is supplied with valve control air through the air supply pipe (211) by applying power so that the maximum supply pressure is in the range of 0.45 to 1 MPa. Thereafter, the current amount is reduced so that the maximum supply pressure is in the range of 0.1 to 0.45 MPa, and the valve can be opened with the supply area of ​​the air supply pipe (211) reduced. The above pneumatic variable solenoid valve (265) can be installed on one air supply pipe (211).

[0074] More specifically, the pneumatic variable solenoid valve (265) may have a maximum supply pressure of 0.45 to 0.6 MPa and may vary the supply pressure to less than 0.1 to 0.45 MPa. In particular, the pneumatic variable solenoid valve (265) may have a maximum supply pressure of 0.6 MPa and may vary the minimum supply pressure to 0.3 MPa.

[0075] The above control unit (300) can control the operation of the valve unit (200) to control the flow of gas.

[0076] Specifically, the control unit (300) can transmit a set flow rate value to the valve assembly (10, 10`) for flow rate control, and control the operation of the pneumatic control unit (260, 260`) according to the set flow rate value to control the flow rate of the process gas to be supplied to the process chamber (20).

[0077] When the control unit (300) transmits a fluid supply signal and flow rate information, it applies power to the solenoid valves (261, 263, 265) so that valve control air can be supplied at a first supply pressure with a short opening time. Then, after the opening of the membrane valve (250) is completed, the supply pressure can be varied to control the supply of valve control air at a second supply pressure.

[0078] For example, when a fluid supply signal and flow rate information are transmitted, the control unit (300) supplies power to the first solenoid valve (261) to open the first air supply pipe (211) so that valve control air can be supplied at the first supply pressure. At this time, the control unit (300) checks the open state of the first solenoid valve (261) using a sensor.

[0079] Next, when the control unit (300) confirms that the first solenoid valve (261) is open, it applies power to the second solenoid valve (263) to open the second air supply pipe (213) with a short closing time, and then stops supplying power to the first solenoid valve (261). Accordingly, the control unit (300) ensures that valve control air is supplied through the second air supply pipe (213).

[0080] Thereafter, when the supply of fluid is completed, the control unit (300) blocks the power supply to the second solenoid valve (261) to block the supply of valve control air through the second air supply pipe (213).

[0081] That is, the control unit (300) supplies valve control air using the first solenoid valve (261) that is advantageous for opening when initial air pressure is applied, and cuts off the valve control air supply for a short time using the second solenoid valve (261) that is advantageous for closing when air pressure is released, thereby greatly shortening the opening and closing of the valve assembly for flow control, which normally consumes 10 ms / delta, to 2 ms / delta.

[0082] In addition, when a fluid supply signal is transmitted, the control unit (300) applies high current power so that the pneumatic variable solenoid valve (265) operates at maximum supply pressure to shorten the opening time. Accordingly, the air supply pipe (211) is opened. At this time, the control unit (300) uses a sensor to check the opening status of the pneumatic variable solenoid valve (265).

[0083] Next, when the control unit (300) confirms that the pneumatic variable solenoid valve (265) is open, it applies a relatively low current to operate by lowering the supply pressure, thereby reducing the open area of ​​the air supply pipe (211).

[0084] In addition, the control unit (300) cuts off the power supply to the pneumatic variable solenoid valve (265) when the supply of fluid is terminated, thereby cutting off the supply of valve control air through the air supply pipe (211).

[0085] That is, the control unit (300) opens the air supply pipe (211) to operate at the maximum supply pressure by applying high current power so as to shorten the opening time when the initial air pressure is applied. Thereafter, when the air pressure is released, power of a relatively low current is applied so as to reduce the opening area of ​​the air supply pipe (211) so as to create favorable conditions for closing. Accordingly, the opening and closing of the valve assembly for flow control, which typically consumes 10 ms / delta, can be significantly shortened to 2 ms / delta.

[0086] The valve assembly for flow control according to the above-described embodiment opens the valve under supply pressure conditions favorable for opening upon initial pneumatic pressure application, varies the supply pressure to open the valve under supply pressure conditions favorable for closing, and then blocks the gas supply, thereby enabling high-speed opening and closing control. Accordingly, the flow rate of process gas can be precisely controlled, significantly improving the process stability of the substrate processing device.

[0087] In particular, the valve assembly for flow control according to the embodiment can be utilized for controlling gas supply to a substrate processing device for performing atomic layer deposition (ALD).

[0088] Meanwhile, Fig. 6 is a process diagram showing a flow control method according to an embodiment.

[0089] Referring to FIG. 6, a flow control method according to an embodiment may include a step (S100) of supplying gas to a process chamber (20); a step (S200) of maintaining the supply of gas; and a step (S300) of blocking the flow of gas. The flow control method according to an embodiment may be performed using any one of the flow control valve assemblies (10, 10`) according to Embodiments 1 and 2.

[0090] In the step (S100) of supplying gas to the process chamber (20), the control unit (300) receives a gas supply signal and flow rate information, generates a power supply signal, and transmits it to the solenoid valve (261, 265). Accordingly, the solenoid valve (261, 265) opens to supply valve control air at the first supply pressure. Next, the pressurizing rod (220) is driven upward and downward to open the membrane valve (250). Then, the flow of gas through the gas inlet / outlet (100) is permitted, and gas is supplied to the process chamber (20).

[0091] This step may further include a step of checking whether valve control air is supplied at the first supply pressure. Specifically, the open state of the first solenoid valve (261) or the pneumatic variable solenoid valve (265) is checked using a detection sensor (267). If the open state is checked and the first solenoid valve (261) or the pneumatic variable solenoid valve (265) is not opened, the control unit (300) may generate and retransmit a power supply signal.

[0092] Next, in the step (S200) of maintaining the gas supply, the supply pressure is varied so that the valve-controlled air is supplied at a second supply pressure lower than the first supply pressure.

[0093] In this step, a power supply signal is generated from the control unit (300) and transmitted to the second solenoid valve (263), thereby opening the second solenoid valve (263) and supplying valve control air at the second supply pressure. Then, power supply to the first solenoid valve (261) is stopped. Then, the flow rate is controlled to maintain the supply of gas to the process chamber (20).

[0094] Alternatively, in this step, the control unit (300) generates a pneumatic variable signal to reduce the current of the power supply so as to supply valve-controlled air at a second supply pressure lower than the first supply pressure. Then, the flow rate is controlled so as to maintain the supply of gas to the process chamber (20).

[0095] Next, in the step (S300) of blocking the flow of the gas, when the control unit (300) receives a gas blocking signal, a power blocking signal is generated and transmitted to the solenoid valve (263, 265). When the supply of valve control air is stopped by the solenoid valve (263, 265), the pressurized rod (220) is lowered by the elastic restoring member (240) to pressurize the membrane valve (250), thereby blocking the inflow of gas through the inlet hole (111), and thus blocking the flow of gas through the gas inlet / outlet (100).

[0096] The flow control method according to the embodiment enables high-speed control of gas flow supply by controlling the operation of a solenoid valve so as to create favorable conditions for gas flow and blocking. Accordingly, the fluid flow control method according to the embodiment can precisely control the flow rate of process gas and supply it onto the substrate (S) through the gas injection unit (40). Accordingly, the process stability through the substrate processing device (1) can be significantly improved.

[0097] The valve assembly for flow control according to the embodiment opens the valve under supply pressure conditions favorable for opening upon initial pneumatic pressure application, varies the supply pressure to open the valve under supply pressure conditions favorable for closing, and then blocks the gas supply, thereby enabling high-speed opening and closing control. Accordingly, the flow rate of process gas can be precisely controlled, significantly improving the process stability of the substrate processing device.

Claims

1. A gas inlet / outlet section including an inlet path through which a substrate processing gas is introduced, an outlet path connected to a process chamber where substrate processing is performed and supplying the gas, and a valve compartment connecting the inlet path and the outlet path; A valve section for controlling the flow rate of the gas passing through the valve compartment, including a membrane valve installed on the upper portion of the inflow path, a pressurizing rod for controlling the opening rate of the inflow path and the flow rate of the gas by pressurizing the membrane valve, and an air pressure control unit for controlling the supply of valve control air for driving the pressurizing rod up and down; and A control unit for controlling the operation of the above valve unit is included; The above control unit, A valve assembly for controlling the operation of the pneumatic control unit to open the membrane valve by supplying the valve control air with a first supply pressure, then supplying the valve control air with a second supply pressure lower than the first supply pressure, and close the membrane valve at the second supply pressure.

2. In paragraph 1, The above valve part, A valve body having an internal space formed therein and having at least one air supply pipe connected to one side through which the valve control air flows in and out; and A valve assembly for controlling flow rate, comprising: a piston that divides the receiving space of the valve body into sections, and raises and lowers the pressurized rod by moving up and down along the inner wall surface of the valve body through the inflow and outflow of valve control air into one of the divided spaces.

3. In paragraph 2, The above valve part, A valve assembly for controlling flow rate, comprising an elastic restoring member installed on one side of the piston to provide elastic force to the pressurizing rod to pressurize the membrane valve to close the inlet passage.

4. In paragraph 2, The above valve part, A valve body having a first air supply pipe and a second air supply pipe connected thereto; and An air pressure control unit having a first solenoid valve and a second solenoid valve installed in the first air supply pipe and the second air supply pipe, respectively; The above control unit, Opening the first solenoid valve to supply the valve control air with the first supply pressure, then opening the second solenoid valve and closing the first solenoid valve to supply the valve control air with the second supply pressure, A valve assembly for flow control, wherein the first solenoid valve and the second solenoid valve have different maximum supply pressures.

5. In paragraph 4, The above valve part, A valve assembly for flow control, characterized in that it further includes a detection sensor installed on one side of the first solenoid valve to check the open state of the first solenoid valve.

6. In paragraph 4, A valve assembly for flow control, characterized in that the first solenoid valve has a maximum supply pressure of 0.45 to 1 MPa, and the second solenoid valve has a maximum supply pressure of less than 0.1 to 0.45 MPa.

7. In paragraph 6, A valve assembly for flow control, characterized in that the first solenoid valve has a maximum supply pressure of 0.6 MPa, and the second solenoid valve has a maximum supply pressure of 0.3 MPa.

8. In paragraph 2, The above valve part, A pneumatic control unit having a pneumatic variable solenoid valve installed in the above air supply pipe; The above control unit, By applying a first power to the pneumatic variable solenoid valve, the valve control air is supplied at the first supply pressure, and then a second power having a lower current than the first power is applied to the pneumatic variable solenoid valve to control the supply of the valve control air at the second supply pressure. The above pneumatic variable solenoid valve, A valve assembly for flow control, characterized in that the opening ratio is adjusted according to the current amount of the authorized power source.

9. In paragraph 8, A valve assembly for flow control, characterized in that the first supply pressure is 0.45 to 1 MPa and the second supply pressure is less than 0.1 to 0.45 MPa.

10. A process chamber having a processing space formed inside for performing substrate processing; A substrate support member installed inside the above processing space on which a substrate is mounted; A gas injection unit for injecting gas into the processing space for processing the substrate; A gas supply unit for supplying process gas to the above gas injection unit; and A substrate processing device including a flow rate control valve assembly according to any one of claims 1 to 9, which is installed between the gas supply unit and the gas injection unit and controls the flow rate of gas.

11. In paragraph 10, The above substrate processing device, A substrate processing device characterized by being used for performing atomic layer deposition (ALD).

12. In a flow control method using a flow control valve assembly described in any one of clauses 1 to 9, A step of receiving a gas supply signal, supplying valve control air at a first supply pressure to open the membrane valve to allow the flow of gas through the gas inlet / outlet port, and supplying gas to the process chamber; A step of varying the supply of the valve-controlled air to a second supply pressure lower than the first supply pressure and maintaining the supply of the gas to the process chamber; and A flow control method comprising: a step of receiving a gas cutoff signal and cutting off the supply of the valve control air to cut off the flow of gas through the gas inlet / outlet.

13. In paragraph 12, The step of supplying gas to the above process chamber is: A flow control method further comprising a step of checking whether valve regulating air is supplied at the first supply pressure.

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