Pressure control device, working method, and substrate processing device

Abstract

The present application provides a pressure control device capable of eliminating flow rate variation of fluid caused by temperature, maintaining constant flow rate, a working method, and a substrate processing device. A pressure control device for fluid supplied to a substrate processing device using plasma according to the present application includes a fluid supply pipe forming a path for the fluid to flow, a control valve disposed at a flow inlet side of the fluid supply pipe, a flow meter measuring flow rate of the fluid flowing in the fluid supply pipe, a pressure gauge measuring pressure of the fluid flowing in the fluid supply pipe, and a valve controller controlling opening degree of the control valve. A perforated plate having a plurality of holes is disposed between the control valve and the flow meter in the fluid supply pipe. A temperature sensor measuring temperature of the fluid is provided at one side of the perforated plate.

Description

Technical Field

[0001] The present invention relates to a pressure control device for controlling the pressure of a fluid, and a substrate processing apparatus for the pressure control device including a flow control method and the pressure control device. Background Technology

[0002] Semiconductor (or display) manufacturing processes are the processes used to fabricate semiconductor devices on a substrate (e.g., a wafer), including processes such as exposure, deposition, etching, ion implantation, and cleaning. To perform these processes, cleanrooms in semiconductor manufacturing plants are equipped with semiconductor manufacturing equipment to handle the substrates fed into the equipment.

[0003] In semiconductor manufacturing, plasma-based processes, such as etching and deposition, are widely used. Plasma processing is performed by placing a substrate in the lower part of a plasma processing space and applying RF (radio frequency) signals to electrodes located at the upper and lower parts, along with the supply of processing gases for plasma processing.

[0004] On the other hand, in plasma processing, the temperature of the substrate can be adjusted from a high temperature of over 100°C to a low temperature of -10°C. A fluid is supplied to the substrate to uniformly control the temperature of the entire area of ​​the substrate. A pressure control device for supplying the fluid at the desired pressure is located on the supply line, and a pressure gauge and a flow meter are located inside the pressure control device.

[0005] Since fluid flow rate is essential information for determining whether there is a fluid leak in the fluid supply line or the lifespan of components located in the fluid supply line, the fluid flow rate within the pressure control device needs to be kept constant unless other factors occur. However, due to heat from components surrounding the pressure control device, such as those in a cavity, the internal temperature of the pressure control device may vary, and the fluid flow rate may change due to these temperature variations. If such temperature-induced fluid flow rate changes occur, it becomes difficult to accurately measure the fluid flow rate. Summary of the Invention

[0006] The present invention provides a pressure control device, a flow control method, and a substrate processing device that can eliminate fluid flow rate changes caused by temperature and maintain a constant flow rate.

[0007] The pressure control device for supplying fluid to a plasma-utilizing substrate processing apparatus according to the present invention comprises: a fluid supply pipe forming a path for the fluid to flow; a control valve disposed at the inlet side of the fluid supply pipe; a flow meter for measuring the flow rate of the fluid flowing in the fluid supply pipe; a pressure gauge for measuring the pressure of the fluid flowing in the fluid supply pipe; and a valve controller for controlling the opening degree of the control valve. The pressure control device further comprises a perforated plate having a plurality of holes formed in the fluid supply pipe between the control valve and the flow meter, and having a temperature sensor for measuring the temperature of the fluid.

[0008] The method of operating the pressure control device according to the present invention for controlling the pressure of fluid supplied to the substrate processing apparatus includes the step of controlling the control valve based on the flow rate value measured by the flow meter, the pressure value measured by the pressure gauge, and the temperature value measured by the temperature sensor.

[0009] The plasma-based substrate processing apparatus according to the present invention includes: a cavity having a processing space inside; a substrate support unit disposed in the processing space and supporting a substrate; a fluid supply unit supplying a fluid for temperature regulation to the substrate through the substrate support unit; a gas supply unit supplying a processing gas to the processing space; and a plasma generating unit for generating plasma from the processing gas.

[0010] According to the present invention, a temperature sensor is provided in the perforated plate of the fluid supply pipe disposed in the flow controller. The temperature of the fluid flowing along the fluid supply pipe can be accurately measured by the temperature sensor. By controlling the control valve corresponding to the temperature change, the flow rate of the fluid can be kept constant in the flow controller even if the temperature changes. Attached Figure Description

[0011] Figure 1 A simplified structure of the substrate processing apparatus according to the present invention is shown.

[0012] Figure 2 The substrate support unit and the fluid supply unit are shown.

[0013] Figure 3 The structure of the fluid supply unit is shown.

[0014] Figure 4 The structure of the pressure control device is shown.

[0015] Figure 5 The image shows a perforated plate with a temperature sensor inserted into a fluid supply pipe.

[0016] Figure 6 as well as Figure 7 The perforated plate is shown.

[0017] Figure 8 This shows fluid flowing through a perforated plate in a fluid supply pipe.

[0018] Figure 9 This is a flowchart illustrating an example of a flow control method in a pressure control device according to the present invention.

[0019] (Explanation of reference numerals in the attached diagram)

[0020] 10: Substrate processing apparatus

[0021] 100: Cavity

[0022] 200: Substrate support unit

[0023] 300: Fluid supply unit

[0024] 320: Fluid supply source

[0025] 340: Fluid supply line

[0026] 350: Pressure control device

[0027] 380: Fluid discharge line

[0028] 400: Plasma Generating Unit

[0029] 500: Gas Supply Unit

[0030] 600: Control Unit

[0031] 710: Fluid supply pipe

[0032] 720: Control valve

[0033] 730: Flow meter

[0034] 740: Pressure gauge

[0035] 750: Valve controller

[0036] 760: Perforated plate

[0037] 770: Temperature sensor Detailed Implementation

[0038] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art to which this invention pertains can readily implement it. The present invention can be implemented in various different ways and is not limited to the embodiments described herein.

[0039] To clearly illustrate the invention, irrelevant parts have been omitted, and the same or similar components are marked with the same reference numerals throughout the specification.

[0040] Furthermore, in multiple embodiments, the same reference numerals are used to describe only representative embodiments of the constituent elements having the same structure, while in other embodiments only structures different from the representative embodiments are described.

[0041] In the specification as a whole, when a part is described as being "connected (or combined)" with other parts, it includes not only the case of "direct connection (or combination)" but also the case of "indirect connection (or combination)" where other components are placed in between. Furthermore, when a part is described as "including" a constituent element, unless otherwise stated otherwise, it means that other constituent elements may be included, rather than excluding them.

[0042] Unless otherwise defined, all terms used herein, including technical or scientific terms, shall have the same meaning as commonly understood by one of ordinary knowledge in the art to which this invention pertains. Terms such as those defined in commonly used dictionaries shall be interpreted as having the same meaning as in the relevant technical context, and shall not be ideally or excessively interpreted as having a formal meaning unless expressly defined in this application.

[0043] Figure 1 A simplified structure of the substrate processing apparatus 10 according to the present invention is shown. (Refer to...) Figure 1 According to an embodiment of the present invention, the substrate processing apparatus 10 is an apparatus for performing etching or deposition processes on a substrate using plasma. The substrate processing apparatus 10 may include a cavity 100, a substrate support unit 200, a fluid supply unit 300, a plasma generation unit 400, a gas supply unit 500, and a control unit 600.

[0044] The cavity 100 has a processing space for performing plasma processes. The cavity 100 may have an exhaust port 102 at its lower part, which can be connected to a discharge line equipped with a pump P. The exhaust port 102 can discharge reaction byproducts generated during the plasma process and residual gases inside the cavity 100 to the outside of the cavity 100 via the discharge line. At this time, the internal space of the cavity 100 can be depressurized to a predetermined pressure.

[0045] The cavity 100 may have an opening 104 formed in its sidewall. The opening 104 can serve as a passage for the substrate W to enter and exit the interior of the cavity 100. Such an opening 104 can be configured to open and close via a door assembly.

[0046] The substrate support unit 200 can be disposed in the lower region inside the cavity 100. The substrate support unit 200 can support the substrate W by electrostatic force. However, this embodiment is not limited to this, and the substrate W can be supported by various methods such as mechanical clamping or vacuum.

[0047] The substrate support unit 200 may include a support body 210 and an electrostatic chuck 220 disposed on the support body 210. The electrostatic chuck 220 may be configured as an electrostatic adsorption substrate W and may include a ceramic layer with electrodes inserted.

[0048] Although not shown inside the substrate support unit 200, the substrate support unit 200 may include a heating element or a cooling element, or both, to maintain the substrate W at the process temperature. The heating element may be a heating coil, and the cooling element may provide a cooling line through which refrigerant flows. Additionally, a flow path for a fluid (e.g., an inert gas, more specifically, helium) for transferring temperature is formed inside the substrate support unit 200, so that the temperature of the substrate support unit 200 can be uniformly transferred to the substrate W, and the fluid can flow to the underside of the substrate W through the hole 222 located in the upper part of the support body 210.

[0049] Reference Figure 2 The substrate support unit 200 may include a fluid supply unit 300 for supplying fluid to the rear of the substrate W. According to an embodiment of the present invention, the substrate support unit 200 may be divided into four regions S10, S20, S30, and S40, each region potentially having a concentric circular shape. It may be divided into a first region S10, a second region S20, a third region S30, and a fourth region S40 with the center of the substrate support unit 200 as a reference, and each region may be connected to a fluid supply line 340 of the fluid supply unit 300 (described later). Fluid supplied from the fluid supply source 320 may be supplied to the first region S10, the second region S20, the third region S30, and the fourth region S40 via the fluid supply line 340. A valve 322 may be provided in the passage connecting the fluid supply source 320 and the fluid supply line 340 for opening and closing the passage or for regulating the flow rate of the fluid flowing through it.

[0050] exist Figure 1 as well as Figure 2While the example shown divides the substrate support unit 200 into four regions, the fluid supply path in this invention is not limited to four regions. For example, the substrate support unit 200 may consist of two regions, controlling the pressure and flow rate of the fluid supplied to both regions. Alternatively, the substrate support unit 200 may consist of one region, controlling the flow rate and pressure of the fluid supplied to that region. Furthermore, the substrate support unit 200 may be divided into four or more regions.

[0051] Refer again Figure 1 The plasma generating unit 400 can generate plasma in the processing space of the cavity 100. The plasma can be formed in the region above the substrate support unit 200 within the cavity 100. According to an embodiment of the present invention, the plasma generating unit 400 can generate plasma in the processing space inside the cavity 100 using a capacitively coupled plasma (CCP) source.

[0052] However, this embodiment is not limited to this. The plasma generating unit 400 may also use an inductively coupled plasma (ICP) source or other plasma sources such as microwave to generate plasma in the processing space inside the cavity 100.

[0053] The plasma generating unit 400 may include a high-frequency power supply 402 and a matching unit 404. The high-frequency power supply 402 can supply high-frequency power to either the upper or lower electrode to generate a potential difference between the upper and lower electrodes. Here, the upper electrode may be the nozzle 410, and the lower electrode may be the substrate support unit 200. Alternatively, the high-frequency power supply 402 may be connected to the lower electrode, and the upper electrode may be grounded.

[0054] The nozzle 410 can be formed inside the cavity 100, vertically opposite to the substrate support unit 200. Such a nozzle 410 can have multiple gas injection holes for uniformly injecting gas into the cavity 100, and can be provided with a diameter larger than that of the electrostatic chuck 220. Alternatively, the nozzle 410 can be made of silicon or metal.

[0055] The gas supply unit 500 can supply the gas required for the process to the cavity 100. Such a gas supply unit 500 may include a gas supply source 502, a gas supply line 504, and a gas nozzle. The gas supply line 504 can connect the gas supply source 502 and the gas nozzle. A valve 506 may be provided on the gas supply line 504 for opening and closing its passage or for regulating the flow rate of the fluid in its passage.

[0056] The control unit 600 can comprehensively control the operation of the board processing apparatus 10 configured as described above. As an example, the control unit can be a computer, equipped with a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), auxiliary memory, etc. The CPU can operate based on programs or processing conditions stored in the ROM or auxiliary memory and control the overall operation of the board processing apparatus 10.

[0057] According to an embodiment of the present invention, the control unit 600 can supply gas to the processing space inside the cavity 100 for performing a process, and control the gas to be plasmaized by the plasma generating unit 400. In addition, the control unit 600 can control the flow rate of the fluid supplied to the substrate support unit 200 by controlling the valves 322, 342a to 348a, pressure regulator 352, and flow regulator 354 of the fluid supply unit 300, thereby accelerating the stabilization of the fluid.

[0058] Figure 3 This is a diagram illustrating a fluid supply unit according to an embodiment of the present invention.

[0059] Reference Figure 3 The fluid supply unit 300 may include a fluid supply source 320, a fluid supply line 340, a pressure control device 350, an orifice 370, and a fluid discharge line 380.

[0060] The fluid supply source 320 can supply fluid to the fluid supply line 340 for regulating the temperature of the substrate W. According to one embodiment of the invention, the fluid can be helium (He), but is not limited thereto. A valve 322 can be provided in the passage connecting the fluid supply source 320 and the fluid supply line 340 for opening and closing the passage or for regulating the flow rate of the fluid flowing through it.

[0061] Alternatively, one end of the fluid supply line 340 can be connected to the fluid supply source 320, and the other end of the fluid supply line 340 can branch into multiple fluid supply lines 342, 344, 346, and 348. More specifically, the fluid supply line 340 can branch into a first fluid supply line 342, a second fluid supply line 344, a third fluid supply line 346, and a fourth fluid supply line 348. The multiple fluid supply lines 342, 344, 346, and 348 can supply fluid to the bottom surface of the substrate W.

[0062] According to one embodiment of the present invention, a first fluid supply line 342 can supply fluid branching from a fluid supply source 320 to a first region S10 corresponding to the center of the substrate support unit 200. A second fluid supply line 344 can supply fluid branching from a fluid supply source 320 to a second region S20 corresponding to the outer side of the first region S10 of the substrate support unit 200. A third fluid supply line 346 can supply fluid branching from a fluid supply source 320 to a third region S30 corresponding to the outer side of the second region S20 of the substrate support unit 200. A fourth fluid supply line 348 can supply fluid branching from a fluid supply source 320 to a fourth region S40 formed outside the third region S30 of the substrate support unit 200. According to an embodiment of the present invention, valves 342a, 344a, 346a, and 348a may be provided in the channels for supplying the received fluid to the regions S10, S20, S30, and S40 of the substrate support unit 200, for opening and closing the channels or for regulating the flow rate of the fluid flowing through them.

[0063] Pressure control devices 350 for detecting and regulating the pressure of the fluid can be configured on multiple fluid supply lines 342, 344, 346, and 348. Pressure control devices 350 can be provided as first pressure control devices 352, 354, 356, and 358 on the first to fourth fluid supply lines 342, 344, 346, and 348, respectively. According to one embodiment of the invention, the pressure of each fluid supplied to the first to fourth fluid supply lines 342, 344, 346, and 348 is preferably 20 to 30 Torr, and the multiple pressure control devices 352, 354, 356, and 358 can be EPCs (Electronic Pressure Controllers).

[0064] Fluid discharge line 380 can discharge the supplied fluid. One end of fluid discharge line 380 may be connected to pump P, and the other end may branch into multiple fluid discharge lines 382-388. According to the present invention, fluid discharge line 380 may include a first fluid discharge line 382, ​​a second fluid discharge line 384, a third fluid discharge line 386, and a fourth fluid discharge line 388. Fluid discharge line 380 can be connected to fluid supply line 340. Specifically, the first fluid discharge line 382 can be connected to the first fluid supply line 342 and discharge fluid supplied to the second fluid supply line 342 via pump P. The second fluid discharge line 384 can be connected to the second fluid supply line 344 and discharge fluid supplied to the second fluid supply line 344 via pump P. The third fluid discharge line 386 can be connected to the third fluid supply line 346 and discharge fluid supplied to the third fluid supply line 346 via pump P. The fourth fluid discharge line 388 can be connected to the fourth fluid supply line 348 to discharge the fluid supplied to the fourth fluid supply line 348 via pump P.

[0065] An orifice 370 is provided on fluid discharge line 380 to constantly regulate the flow rate of fluid discharged to pump P. The orifice 370 is realized by a structure formed on the fluid discharge line 380. The orifice 370 can measure the velocity and flow rate of the fluid on the fluid discharge line 380, providing a constant flow of fluid. A first orifice 372 is provided on a first fluid discharge line 382, ​​a second orifice 374 is provided on a second fluid discharge line 384, a third orifice 376 is provided on a third fluid discharge line 386, and a fourth orifice 378 is provided on a fourth fluid discharge line 388.

[0066] Figure 4 The configuration of the pressure control device 350 is shown. The pressure control device 350 regulates the pressure of the fluid flowing through the fluid supply line 340. The pressure control device 350 includes a fluid supply line 710, a control valve 720, a flow meter 730, a pressure gauge 740, and a valve controller 750. Further, the pressure control device 350 may include a switching valve 790.

[0067] A fluid supply pipe 710 is formed in the pressure control device 350 as a path for fluid flow. The fluid supply pipe 710 is a piping through which fluid can flow. The fluid supply pipe 710 can be connected to the fluid supply line 340. The fluid supply pipe 710 is integral with the fluid supply line 340, acting as a part of the fluid supply line 340. Fluid flows from the pressure control device 350 into the inlet of the fluid supply pipe 710 and exits from the outlet of the fluid supply pipe 710. Figure 4 The arrow indicates the direction of fluid supply to the fluid supply pipe 710. A switching valve 790 may be configured on the upper part of the inlet end of the fluid supply pipe 710. The switching valve 790 is open to allow fluid to flow into the pressure control device 350 or closed to prevent fluid from flowing into the pressure control device 350.

[0068] Control valve 720 can be configured on the inlet side of fluid supply line 710. The opening degree of control valve 720 is adjusted according to its valve position. The valve position of control valve 720 is controlled by valve controller 750. The pressure of the fluid flowing through fluid supply line 710 can be adjusted according to the opening degree of control valve 720. In this document, valve position refers to the degree of valve opening in control valve 720. The valve position is determined by a control signal from valve controller 750.

[0069] Flow meter 730 measures the flow rate of the fluid flowing through fluid supply pipe 710. The flow rate measured by flow meter 730 is the amount of fluid passing through a cross section of fluid supply pipe 710 per unit time. In fluid supply pipe 710, flow meter 730 can be located downstream of control valve 720 with reference to the direction of fluid supply.

[0070] Pressure gauge 740 measures the pressure of a flowing fluid through fluid supply line 710. The pressure measured by pressure gauge 740 is the degree of force exerted by the fluid at a specific point. The pressure of the fluid may be affected by the fluid's density, temperature, or velocity. In fluid supply line 710, pressure gauge 740 may be located downstream of flow meter 730 with reference to the direction of fluid supply.

[0071] Valve controller 750 controls control valve 720. Valve controller 750 uses the correlation between pressure and flow rate to control control valve 720 so that the fluid can maintain a constant pressure. Generally, if the flow rate increases, the pressure decreases, and if the flow rate decreases, the pressure increases; therefore, valve controller 750 can appropriately adjust the valve position of control valve 720 to maintain the fluid pressure. Valve controller 750 may include input / output terminals and control circuitry. Input / output terminals are provided for receiving measurement signals from flow meter 730, pressure gauge 740, and temperature sensor 770 (described later), and transmitting control signals for controlling the valve position to control valve 720. Control circuitry is provided for generating control signals based on the received measurement signals. Valve controller 750 may include a memory for storing data required to control control valve 720 and a processor for processing the data.

[0072] The flow rate measured by flow meter 730 is used to determine whether there is a fluid leak in fluid supply line 340 or whether there is damage to components surrounding fluid supply line 340. Preferably, the fluid flow rate remains constant unless there are other external factors.

[0073] Components located around the pressure control device 350, such as those in the cavity 100, may cause temperature variations in the fluid flowing through the pressure control device 350 due to heat or heat conduction occurring within the cavity 100. For example, the temperature of the fluid flowing through the pressure control device 350 may change due to heat conduction from heating or cooling components included in the substrate support unit 200 within the cavity 100. This temperature-induced flow rate variation in the fluid becomes noise when measuring the flow rate. Therefore, the pressure control device 350 of the present invention provides a method for eliminating flow rate variations caused by external temperature or external environment (cavity heat conduction) and maintaining a constant flow rate.

[0074] According to the present invention, a perforated plate 760 with a plurality of holes 760H is disposed between a control valve 720 and a flow meter 730 in a fluid supply pipe 710. A temperature sensor 770 for measuring the temperature of the fluid is provided on one side of the perforated plate 760.

[0075] Figure 5 As in Figure 4 Region A, from fluid supply pipe 710 to control valve 720 and flow meter 730, shows a perforated plate 760 in which a temperature sensor 770 is inserted into fluid supply pipe 710. (See reference...) Figure 5 A perforated plate 760 is inserted into a portion of the fluid supply pipe 710. A protrusion 760A is formed on the upper part of the perforated plate 760, and a temperature sensor 770 is inserted, embedded, or installed in the protrusion 760A.

[0076] Figure 6 as well as Figure 7 The perforated plate 760 is shown. Figure 6 This is a 3D view of the perforated plate 760. Figure 7 This is the front view of the perforated plate 760. (Refer to...) Figure 6 as well as Figure 7 The perforated plate 760 is a four-cornered plate with a protrusion 760A formed on one side. A sensor hole 760Aa for inserting a temperature sensor 770 is formed in the protrusion 760A of the perforated plate 760. The temperature sensor 770 can be inserted into the sensor hole 760Aa in the form of a probe. In the perforated plate 760, the holes 760H are arranged in concentric circles. The perforated plate 760 can also be referred to as a perforated plate.

[0077] The temperature value of the fluid measured by the temperature sensor 770 can be transmitted to the valve controller 750. The valve controller 750 can control the control valve 720 based on at least one of the flow rate measured by the flow meter 730, the pressure value measured by the pressure gauge 740, and the temperature value measured by the temperature sensor 770.

[0078] The flow rate of a fluid can vary depending on its temperature; therefore, valve controller 750 can control control valve 720 to maintain a constant flow rate to compensate for temperature variations in the fluid. For this purpose, valve controller 750 can pre-store a flow rate and pressure gauge reflecting the fluid temperature. The flow rate and pressure gauge maps the currently measured flow rate value, pressure value, and valve position corresponding to the pressure of the target fluid. In this invention, the flow rate and pressure gauge may include the currently measured temperature value. That is, the flow rate and pressure gauge maps the currently measured temperature value, flow rate value, pressure value, and valve position corresponding to the pressure of the target fluid.

[0079] One perforated plate 760 may be installed in the fluid supply pipe 710, or two or more perforated plates 760 may be installed in the fluid supply pipe 710. Figure 5 In this example, multiple perforated plates 760 are arranged at certain intervals in the fluid supply pipe 710. (Refer to...) Figure 5 In the fluid supply pipe 710, there may be three perforated plates 760 between the control valve 720 and the flow meter 730. The spacing between the perforated plates 760 may be the same. The fluid supply pipe 710 may be divided into four sections. The fluid supply pipe 710 is provided as a square pipe with a flow path having a circular cross-section inside.

[0080] In the fluid supply pipe 710, the spacing between the multiple perforated plates 760 is determined such that the fluid can maintain laminar flow. Figure 6 , 7 As shown, the holes 760H of each perforated plate 760 are arranged in the same manner, and the spacing between the perforated plates 760 is also configured in the same way. Therefore, as Figure 8 As shown, fluids such as helium (He) can flow in laminar flow within the fluid supply pipe 710 without turbulence.

[0081] A temperature sensor 770 is inserted into a sensor hole 760Aa formed in the protrusion 760A of the perforated plate 760. When multiple perforated plates 760 are provided, the temperature is measured at multiple points by inserting the temperature sensor 770 into each perforated plate 760.

[0082] Temperature values ​​measured by multiple temperature sensors 770 disposed in multiple perforated plates 760 can be transmitted to a flow meter 730. The flow meter 730 can transmit the temperature value and the measured flow rate of the fluid to a valve controller 750. In other embodiments, the temperature sensors 770 can directly transmit the temperature value to the valve controller 750.

[0083] The valve controller 750 can control the control valve 720 based on the average temperature value provided by multiple temperature sensors 770, the flow rate value measured by the flow meter 730, and the pressure value measured by the pressure gauge 740.

[0084] In a pressure control device 350 that controls the pressure of a fluid supplied to a substrate processing apparatus 10 according to the invention, a flow control method for the fluid can be executed by a valve controller 750. The flow control method according to the invention includes the step of the valve controller 750 controlling a control valve 720 based on at least one of a flow rate value measured by a flow meter 730, a pressure value measured by a pressure gauge 740, and a temperature value measured by a temperature sensor 770. In this invention, the valve controller 750 can use a temperature value measured by a temperature sensor 770 to control the control valve 720. Alternatively, the valve controller 750 can use the average value (average temperature value) of temperature values ​​received from multiple temperature sensors 770 to control the control valve 720.

[0085] Figure 9 This is a flowchart illustrating an example of a flow control method in a pressure control device 350 according to the present invention. Figure 9 The flow control method can be executed by valve controller 750. Figure 9 An example is shown of the process by which valve controller 750 controls control valve 720.

[0086] The steps of valve controller 750 controlling control valve 720 include: setting an initial pressure value (S810); setting the valve position of control valve 720 with a flow rate corresponding to the initial pressure value (S820); determining whether the temperature value is within a reference temperature range (S830); calculating the valve position according to a temperature correction coefficient corresponding to the temperature value when the temperature value exceeds the reference temperature range, and setting the reference temperature range using the temperature value as the reference temperature (S840); and comparing the pressure value and flow rate value with the values ​​in a lookup table to determine whether they are within the error range (S850).

[0087] In step S810, an initial pressure value is set in valve controller 750. This initial pressure value is either input by the user or preset. The initial pressure value can vary based on external input. The initial pressure value is the pressure of the fluid specified by the user.

[0088] In step S820, valve controller 750 sets the valve position of control valve 720 with a flow rate corresponding to the initial pressure value. Valve controller 750 determines the pressure value measured by pressure gauge 740, the flow rate value measured by flow meter 730, and the valve position corresponding to the target initial pressure value from a pressure-flow lookup table, and controls the opening degree of control valve 720 to match the valve position. According to steps S840 and S850 described later, valve controller 750 can further set the valve position of control valve 720.

[0089] In step S830, valve controller 750 determines whether the measured temperature value is within a reference temperature range. Valve controller 750 receives the temperature value measured by temperature sensor 770 and determines whether the received temperature value is within the reference temperature range. Valve controller 750 can use the average of the temperature values ​​measured by multiple temperature sensors 770 as the temperature value. The reference temperature range is the temperature range within which the pressure control device 350 can maintain the current pressure and flow rate.

[0090] When the measured temperature value exceeds the reference temperature range, if the fluid pressure is controlled solely based on the flow-pressure lookup table, the fluid flow rate may become inconsistent and fluctuate. In step S840, when the temperature value exceeds the reference temperature range, the valve controller 750 calculates the valve position based on a temperature correction factor corresponding to the temperature value and sets the reference temperature range using that temperature value as the reference temperature. In step S820, the valve controller 750 applies the temperature correction factor to the value indicating the valve position based on the measured temperature value and changes the valve position accordingly. Furthermore, the valve controller 750 re-sets the reference temperature range using the currently measured temperature as the reference temperature. While the reference temperature range is re-set, the valve controller 750 can control the control valve 720 based on the measured flow rate and pressure values ​​in the pressure-flow-pressure lookup table corresponding to the currently measured temperature.

[0091] If the temperature value is within the reference temperature range, in step S850, the valve controller 750 can compare the measured pressure and flow values ​​with the values ​​in the lookup table to determine whether they are within the error range. When either the pressure value measured by the pressure gauge 740 or the flow value measured by the flow meter 730 exceeds the error range in the pressure-flow lookup table, the valve controller 750 returns to step S820 to control the opening degree of the control valve 720.

[0092] Through the process described above, the valve controller 750 controls the control valve 720 by taking the fluid temperature into account, thereby guiding a constant flow through the fluid supply pipe 710 even when the fluid temperature changes. This compensates for fluid flow variations caused by external temperature, allowing for more precise control of fluid pressure while detecting fluid leaks.

[0093] Table 1

[0094]

[0095] Table 1 shows an example of the above lookup table. In step S810, the initial setting can be a pressure of 30 Torr (row 1 of Table 1) with a flow rate of 30 sccm, a temperature of 30°C, and a control valve 720 position of 40%. This is the initial setting, so a temperature correction factor may not be assigned. Even if the temperature changes with the processing of the substrate W or the passage of time, the lookup table can include a temperature correction factor corresponding to the temperature change in order to reduce the deviation of the flow rate.

[0096] For example, if the initial temperature is 30°C and the measured temperature is confirmed to be 35°C due to heat conduction from the cavity 100, it can be confirmed that the measured temperature of the valve controller 750 exceeds the reference temperature range (S830). It can be confirmed that the valve controller 750 has a temperature correction factor of 0.99 corresponding to the measured temperature of 35°C in Table 1 (row 2 of Table 1), and the position of the control valve 720 is calculated to be 39.6% (=40×0.99) (S840). Then, the valve controller 750 can readjust the position of the control valve 720 from 40% to 39.6%, and set this temperature as the new reference temperature (S820). Even if the temperature changes from 30°C to 35°C, by adjusting the position of the control valve 720 to 39.6%, the flow rate of 30 sccm and the pressure of 30 Torr can be kept constant.

[0097] Conventionally, with the fluid supply direction as the reference, the flow meter is located at the front end and the control valve at the rear end. However, according to an embodiment of the present invention, the control valve 720 may be located at the front end, the flow meter 730 at the rear end, and the temperature sensor 770 between the control valve 720 and the flow meter 730. The valve controller 750 may pre-store a lookup table with temperature correction coefficients based on pressure, fluid, and temperature, as described in Table 1 above. Therefore, if the valve controller 750 receives feedback from the flow meter 730 and the temperature sensor 770 to control the control valve 720 located at the front end, the accuracy of fluid flow through the control valve 720 can be improved.

[0098] This embodiment and the accompanying drawings are merely illustrative of a portion of the technical concept included in this invention. It is obvious that variations and specific embodiments that can be readily derived by those skilled in the art within the scope of the technical concept included in the specification and drawings of this invention are all included within the scope of the claims of this invention.

[0099] Therefore, the concept of the present invention should not be limited to the illustrated embodiments, not only to the appended claims, but also to any equivalent or modified versions thereof.

Claims

1. A pressure control device, which is a pressure control device for fluid supplied to a substrate processing apparatus, wherein, The pressure control device includes: A fluid supply pipe forms a path for the flow of the fluid; A control valve is disposed on the inlet side of the fluid supply pipe; A flow meter for measuring the flow rate of the fluid flowing in the fluid supply pipe; A pressure gauge for measuring the pressure of the fluid flowing in the fluid supply pipe; A valve controller that controls the opening degree of the control valve; and A perforated plate, in the fluid supply pipe, has multiple holes formed between the control valve and the flow meter, and has a temperature sensor for measuring the temperature of the fluid.

2. The pressure control device according to claim 1, wherein, The valve controller controls the control valve based on the flow rate measured by the flow meter, the pressure value measured by the pressure gauge, and the temperature value measured by the temperature sensor.

3. The pressure control device according to claim 1, wherein, The perforated plate is a quadrilateral plate with a protrusion on one side. A sensor hole for inserting the temperature sensor is formed in the protrusion.

4. The pressure control device according to claim 3, wherein, The holes are formed in concentric circles in the perforated plate.

5. The pressure control device according to claim 1, wherein, Multiple perforated plates are arranged at certain intervals in the fluid supply pipe.

6. The pressure control device according to claim 5, wherein, In the fluid supply pipe, the spacing between the plurality of perforated plates is determined such that the fluid can maintain laminar flow.

7. The pressure control device according to claim 5, wherein, Temperature values ​​measured by multiple temperature sensors disposed on multiple perforated plates are transmitted to the valve controller.

8. The pressure control device according to claim 7, wherein, The valve controller controls the control valve based on the average temperature value provided by the plurality of temperature sensors, the flow rate value measured by the flow meter, and the pressure value measured by the pressure gauge.

9. The pressure control device according to claim 1, wherein, The valve controller sets an initial pressure value; sets the valve position of the control valve with a flow rate corresponding to the initial pressure value; determines whether the temperature value of the temperature sensor is within a reference temperature range; and when the temperature value of the temperature sensor exceeds the reference temperature range, changes the valve position according to a temperature correction coefficient corresponding to the temperature value of the temperature sensor.

10. A method of operating a pressure control device, wherein the pressure control device controls the pressure of a fluid supplied to a substrate processing apparatus, wherein, The pressure control device includes: A fluid supply pipe forms a path for the flow of the fluid; A control valve is disposed at the inlet of the fluid supply pipe; A flow meter for measuring the flow rate of the fluid flowing in the fluid supply pipe; A pressure gauge for measuring the pressure of the fluid flowing in the fluid supply pipe; A valve controller that controls the opening degree of the control valve; and A temperature sensor is located in the fluid supply pipe between the control valve and the flow meter. The operating method includes the step of controlling the control valve based on the flow rate measured by the flow meter, the pressure value measured by the pressure gauge, and the temperature value measured by the temperature sensor.

11. The working method according to claim 10, wherein, The steps for controlling the control valve include: The steps for setting the initial pressure value; The step of setting the valve position of the control valve according to the flow rate corresponding to the initial pressure value; The step of determining whether the temperature value is within the reference temperature range; and When the temperature value exceeds the reference temperature range, the valve position is changed according to the temperature correction coefficient corresponding to the temperature value.

12. A substrate processing apparatus utilizing plasma, wherein, The substrate processing apparatus includes: The cavity has processing space inside; A substrate support unit is disposed in the processing space and supports the substrate. A fluid supply unit supplies fluid for temperature regulation to the substrate via the substrate support unit; A gas supply unit supplies processing gas to the processing space; and A plasma generating unit is used to generate plasma from the processed gas. The fluid supply unit includes: A fluid supply source supplies the fluid; A fluid supply line, one end of which is connected to the fluid supply source for supplying the fluid; A pressure control device controls the pressure of the fluid in the fluid supply line; and A fluid discharge line is used to discharge the fluid. The pressure control device includes: A fluid supply pipe forms a path for the flow of the fluid; A control valve is disposed on the inlet side of the fluid supply pipe; A flow meter for measuring the flow rate of the fluid flowing in the fluid supply pipe; A pressure gauge is used to measure the pressure of the fluid flowing in the fluid supply pipe; and A valve controller controls the opening degree of the control valve. A perforated plate with multiple holes is disposed in the fluid supply pipe between the control valve and the flow meter. A temperature sensor for measuring the temperature of the fluid is installed on one side of the perforated plate.

13. The substrate processing apparatus according to claim 12, wherein, The valve controller controls the control valve based on the flow rate measured by the flow meter, the pressure value measured by the pressure gauge, and the temperature value measured by the temperature sensor.

14. The substrate processing apparatus according to claim 12, wherein, The perforated plate is a quadrilateral plate with a protrusion on one side. A sensor hole for inserting the temperature sensor is formed in the protrusion.

15. The substrate processing apparatus according to claim 14, wherein, The holes are formed in concentric circles in the perforated plate.

16. The substrate processing apparatus according to claim 12, wherein, Multiple perforated plates are arranged at certain intervals in the fluid supply pipe.

17. The substrate processing apparatus according to claim 16, wherein, In the fluid supply pipe, the spacing between the plurality of perforated plates is determined such that the fluid can maintain laminar flow.

18. The substrate processing apparatus according to claim 17, wherein, Temperature values ​​measured by multiple temperature sensors disposed on multiple perforated plates are transmitted to the valve controller.

19. The substrate processing apparatus according to claim 18, wherein, The valve controller controls the control valve based on the average temperature value provided by the plurality of temperature sensors, the flow rate value measured by the flow meter, and the pressure value measured by the pressure gauge.

20. The substrate processing apparatus according to claim 19, wherein, The valve controller sets an initial pressure value; sets the valve position of the control valve with a flow rate corresponding to the initial pressure value; determines whether the average temperature value is within a reference temperature range; if the average temperature value is within the reference temperature range, compares the pressure value and the flow rate value with the values ​​in a lookup table to control the control valve; when the average temperature value exceeds the reference temperature range, changes the valve position according to a temperature correction coefficient corresponding to the average temperature value, and uses the average temperature value as the reference temperature to set the reference temperature range.

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