Gas supply system, substrate processing apparatus, and method of operating gas supply system

Abstract

A gas supply system according to the present disclosure comprises a gas supply line and a gas recovery line. The gas supply line supplies heat transfer gas to a gap between a substrate support section and a back surface of a substrate. The gas supply line includes a first part, a second part, a third part, and a pressure controller. The second part is downstream of the first part. The pressure controller adjusts the pressure of the heat transfer gas and is connected between the first part and the second part. The third part connects the second part and the gap. The gas recovery line connects to the first part and the second part. The gas recovery line includes a pump connected between the first part and the second part. The gas recovery line shares the third part with the gas supply line. The gas recovery line returns the heat transfer gas to the first part from the second part.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a gas supply system, a substrate processing apparatus, and a method of operating the gas supply system.

Background Art

[0002] A substrate processing apparatus is used for processing a substrate. Patent Document 1 below discloses a plasma processing apparatus as a kind of substrate processing apparatus. The plasma processing apparatus includes a chamber and a mounting table. The mounting table is provided in the chamber. The mounting table is configured to support a substrate placed thereon. The plasma processing apparatus is configured to supply a heat transfer gas to a gap between the mounting table and the substrate in order to promote heat exchange between the mounting table and the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique for suppressing consumption of the heat transfer gas.

Means for Solving the Problems

[0005] In one exemplary embodiment, a gas supply system is provided. The gas supply system includes a gas supply line and a gas recovery line. The gas supply line is configured to supply a heat transfer gas to a gap between a substrate support and the back surface of the substrate. The gas supply line includes a first portion, a second portion, a third portion, and a pressure controller. The second portion is downstream of the first portion. The pressure controller is configured to adjust the pressure of the heat transfer gas and is connected between the first portion and the second portion. The third portion connects the second portion to the gap. The gas recovery line is connected to the first portion and the second portion. The gas recovery line includes a pump connected between the first portion and the second portion. The gas recovery line shares the third portion with the gas supply line. The gas recovery line is configured to return the heat transfer gas from the second portion to the first portion.

Advantages of the Invention

[0006] According to one exemplary embodiment, it is possible to suppress the consumption of the heat transfer gas.

Brief Description of the Drawings

[0007]

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Mode for Carrying Out the Invention

[0008] Hereinafter, various exemplary embodiments will be described.

[0009] In one exemplary embodiment, a gas supply system is provided. The gas supply system includes a gas supply line and a gas recovery line. The gas supply line is configured to supply a heat transfer gas to a gap between a substrate support and the back surface of a substrate. The gas supply line includes a first portion, a second portion, a third portion, and a pressure controller. The second portion is downstream of the first portion. The pressure controller is configured to adjust the pressure of the heat transfer gas and is connected between the first portion and the second portion. The third portion connects the second portion and the gap. The gas recovery line is connected to the first portion and the second portion. The gas recovery line includes a pump connected between the first portion and the second portion. The gas recovery line shares the third portion with the gas supply line. The gas recovery line is configured to return the heat transfer gas from the second portion to the first portion.

[0010] According to the above embodiment, the heat transfer gas supplied to the gap between the substrate support and the back surface of the substrate is returned to the first portion of the gas supply line and reused. Therefore, consumption of the heat transfer gas is suppressed. Also, the gas supply line and the gas recovery line share the third portion with each other, and the heat transfer gas is returned from the second portion connected to the third portion to the first portion. Therefore, an unintended increase in the pressure of the gas in the third portion and the gap can be suppressed.

[0011] In one exemplary embodiment, the gas recovery line may further include a gas flow path connected between the second portion and the pump, and an orifice that reduces the cross-sectional area of the gas flow path.

[0012] In one exemplary embodiment, the gas recovery line may further include another gas flow path connected between the second portion and the pump.

[0013] In one exemplary embodiment, the gas recovery line may further include a gas flow path connected between the second portion and the pump, and a valve capable of adjusting the opening degree of the gas flow path. In one exemplary embodiment, when the heat transfer gas is supplied from the gas supply line to the gap, the opening degree of the valve may be set to an opening degree smaller than the fully open state.

[0014] In one exemplary embodiment, the third portion may include a valve connected between the second portion and the substrate support portion.

[0015] In one exemplary embodiment, the first portion may include a tank for storing the heat transfer gas. The gas recovery line may be configured to return the heat transfer gas to the tank.

[0016] In one exemplary embodiment, the gas supply system may further include a pressure regulator. The pressure regulator is configured to adjust the pressure of the heat transfer gas in the upstream portion with respect to the pressure controller in the gas supply line. In one exemplary embodiment, the pressure regulator may include a pressure gauge and a valve. The pressure gauge is configured to measure the pressure of the heat transfer gas in the tank. The valve is connected between the source of the heat transfer gas and the first portion and is opened and closed according to the pressure measured by the pressure gauge.

[0017] In one exemplary embodiment, the pressure regulator may set the pressure in the upstream portion with respect to the pressure controller in the gas supply line to a pressure higher than the required supply pressure of the pressure controller.

[0018] In one exemplary embodiment, the gas supply system may further include another gas supply line and another gas recovery line. The another gas supply line is configured to supply a heat transfer gas to the gap. The another gas supply line includes the first portion, another second portion, another pressure controller, and another third portion. The another second portion is downstream of the first portion. The another pressure controller is configured to adjust the pressure of the heat transfer gas and is connected between the first portion and the another second portion. The another third portion connects the another second portion and the gap. The another gas recovery line is connected to the first portion and the another second portion. The another gas recovery line is connected between the first portion and the another second portion. The another gas recovery line is configured to return the heat transfer gas from the another second portion to the first portion.

[0019] In another exemplary embodiment, a substrate processing apparatus is provided. The substrate processing apparatus includes a substrate support portion and a gas supply system according to any of the above-described exemplary embodiments. The substrate support portion is configured to support a substrate placed thereon. The gas supply system is configured to supply a heat transfer gas to a gap between the substrate support portion and the back surface of the substrate.

[0020] In yet another exemplary embodiment, a method of operating a gas supply system according to any of the above-described exemplary embodiments is provided. The method of operation includes a step of supplying a heat transfer gas to a gap between a substrate support portion and the back surface of a substrate through a gas supply line. The method of operation further includes a step of partially recovering the heat transfer gas from a second portion to a first portion through a gas recovery line while the heat transfer gas is being supplied to the gap.

[0021] Hereinafter, various exemplary embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals.

[0022] FIG. 1 and FIG. 2 are diagrams schematically showing a substrate processing apparatus according to one exemplary embodiment. In one embodiment, the substrate processing apparatus is a plasma processing system.

[0023] In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support unit 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. Further, the plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas discharge port for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 described later, and the gas discharge port is connected to an exhaust system 40 described later. The substrate support unit 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0024] The plasma generation unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), ECR plasma (Electron-Cyclotron-resonance plasma), helicon wave plasma (HWP), surface wave plasma (SWP), or the like. Also, various types of plasma generation units including an AC (Alternating Current) plasma generation unit and a DC (Direct Current) plasma generation unit may be used. In one embodiment, the AC signal (AC power) used in the AC plasma generation unit has a frequency in the range of 100 kHz to 10 GHz. Accordingly, the AC signal includes an RF (Radio Frequency) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 200 kHz to 150 MHz.

[0025] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to execute various processes described in the present disclosure. The control unit 2 can be configured to control each element of the plasma processing apparatus 1 to execute the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 can be configured to perform various control operations based on a program stored in the storage unit 2a2. The storage unit 2a2 may include a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0026] Hereinafter, a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is disposed inside the plasma processing chamber 10. The shower head 13 is disposed above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side wall 10a of the plasma processing chamber 10, and the substrate support unit 11. The side wall 10a is grounded. The shower head 13 and the substrate support unit 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0027] The substrate support part 11 includes a main body part 111 and a ring assembly 112. The main body part 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body part 111 surrounds the central region 111a of the main body part 111 in a plan view. The substrate W is disposed on the central region 111a of the main body part 111, and the ring assembly 112 is disposed on the annular region 111b of the main body part 111 so as to surround the substrate W on the central region 111a of the main body part 111. In one embodiment, the main body part 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has the substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Also, although not shown, the substrate support part 11 may include a temperature control module configured to adjust at least one of the electrostatic chuck, the ring assembly 112, and the substrate W to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path.

[0028] The shower head 13 is configured to introduce at least one processing gas from the gas supply part 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas introduction ports 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the plurality of gas introduction ports 13c. Also, the shower head 13 includes a conductive member. The conductive member of the shower head 13 functions as an upper electrode. Note that the gas introduction part may include, in addition to the shower head 13, one or more side gas injectors (SGI) attached to one or more openings formed in the side wall 10a.

[0029] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one processing gas from the corresponding gas source 21 to the showerhead 13 via the corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Further, the gas supply unit 20 may include at least one flow modulation device that modulates or pulses the flow rate of at least one processing gas.

[0030] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive member of the substrate support 11 and / or the conductive member of the showerhead 13. Thereby, plasma is formed from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Also, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, and the ion component in the formed plasma can be drawn into the substrate W.

[0031] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is coupled to the conductive member of the substrate support unit 11 and / or the conductive member of the shower head 13 via at least one impedance matching circuit, and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive member of the substrate support unit 11 and / or the conductive member of the shower head 13. The second RF generation unit 31b is coupled to the conductive member of the substrate support unit 11 via at least one impedance matching circuit, and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a lower frequency than the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to the conductive member of the substrate support unit 11. Also, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0032] In addition, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generation unit 32a and a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is connected to a conductive member of the substrate support unit 11 and is configured to generate a first DC signal. The generated first DC signal is applied to the conductive member of the substrate support unit 11. In one embodiment, the first DC signal may be applied to other electrodes such as the electrodes in the electrostatic chuck. In one embodiment, the second DC generation unit 32b is connected to a conductive member of the shower head 13 and is configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the shower head 13. In various embodiments, the first and second DC signals may be pulsed. Note that the first and second DC generation units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0033] The exhaust system 40 may be connected to, for example, a gas discharge port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbo molecular pump, a dry pump, or a combination thereof.

[0034] Hereinafter, refer to FIG. 3. FIG. 3 is a diagram showing a gas supply system according to one exemplary embodiment. The gas supply system 50 shown in FIG. 3 can be adopted in a substrate processing apparatus such as the plasma processing apparatus 1.

[0035] The gas supply system 50 includes a gas supply line 51 and a gas recovery line 52. The gas supply line 51 is configured to supply a heat transfer gas (for example, helium gas) to the gap between the substrate support unit 11 and the back surface of the substrate W. The gas supply line 51 includes a first portion P1, a second portion P2, a third portion P3, and a pressure controller PC.

[0036] The first part P1 provides a gas flow path connected to the heat transfer gas source GS. The second part P2 is downstream of the first part P1. The second part P2 provides a gas flow path for the heat transfer gas. The pressure controller PC is connected between the first part P1 and the second part P2. The third part P3 is downstream of the second part P2 and provides a gas flow path for the heat transfer gas. The third part P3 connects the second part P2 to the gap between the substrate support part 11 and the back surface of the substrate W. In the gas supply line 51, the heat transfer gas is supplied from the source GS to the gap between the substrate support part 11 and the back surface of the substrate W through the first part P1, the pressure controller PC, the second part P2, and the third part P3.

[0037] In one embodiment, the first part P1 may include a tank TA. The tank TA is a container in which the heat transfer gas is stored. In one embodiment, a valve V1 and a pressure regulator PR may be connected between the first part P1 and the source GS. The valve V1 may be an on-off valve or a valve whose opening degree is adjustable.

[0038] The pressure regulator PR is configured to adjust the pressure of the heat transfer gas in the upstream (primary side) part with respect to the pressure controller PC in the gas supply line 51. In one embodiment, the pressure regulator PR may be a pressure regulator. The pressure regulator PR can set the pressure of the heat transfer gas in the upstream part with respect to the pressure controller PC in the gas supply line 51 to a pressure higher than the required supply pressure of the pressure controller PC. The required supply pressure of the pressure controller PC can be equal to or higher than the maximum pressure of the heat transfer gas output by the pressure controller PC. The pressure of the heat transfer gas output by the pressure regulator PR to the upstream part with respect to the pressure controller PC in the gas supply line 51 is specified from, for example, the control unit 2 to the pressure regulator PR.

[0039] The pressure controller PC is configured to control the pressure of the heat transfer gas output downstream (secondary side) in the gas supply line 51. The pressure of the heat transfer gas output by the pressure controller PC downstream is specified from, for example, the control unit 2 to the pressure controller PC.

[0040] In one embodiment, the valve V21 may be connected between the first part P1 and the pressure controller PC. Also, the valve V22 may be connected between the pressure controller PC and the second part P2. Each of the valve V21 and the valve V22 may be an on-off valve or a valve whose opening degree is adjustable.

[0041] The gas recovery line 52 is connected to the first part P1 and the second part P2. The gas recovery line 52 includes a gas flow path connected between the first part P1 and the second part P2. The gas recovery line 52 further includes a pump PU. The pump PU is connected between the first part P1 and the second part P2 and constitutes a part of the gas flow path of the gas recovery line 52. The gas recovery line 52 is configured to return the heat transfer gas from the second part P2 to the first part P1. In one embodiment, the gas recovery line 52 is configured to return the heat transfer gas from the second part P2 to the tank TA. The gas recovery line 52 shares the third part P3 with the gas supply line 51.

[0042] In one embodiment, the gas recovery line 52 may include a first recovery line 521 and a second recovery line 522. The first recovery line 521 provides a gas flow path connecting the second part P2 and the pump PU. The first recovery line 521 further includes a valve V3 and an orifice OF. The valve V3 and the orifice OF partially constitute the gas flow path of the first recovery line 521. The valve V3 may be an on-off valve or a valve whose opening degree is adjustable. The orifice OF reduces the cross-sectional area of the gas flow path of the first recovery line 521.

[0043] The second recovery line 522 provides another gas flow path connecting the second part P2 and the pump PU. That is, the first recovery line 521 and the second recovery line 522 are connected in parallel between the second part P2 and the pump PU. The second recovery line 522 further includes a valve V4. The valve V4 partially constitutes the gas flow path of the second recovery line 522. The valve V4 may be an on-off valve or a valve with an adjustable opening degree. Note that the second recovery line 522 does not include an orifice. That is, the minimum cross-sectional area of the gas flow path of the second recovery line 522 is larger than the minimum cross-sectional area of the gas flow path of the first recovery line 521.

[0044] Hereinafter, the operation method of the gas supply system 50 will be described. The operation method includes a step of supplying a heat transfer gas to the gap between the substrate support portion 11 and the back surface of the substrate W through the gas supply line 51. The operation method further includes a step of partially recovering the heat transfer gas from the second part P2 to the first part P1 through the gas recovery line 52 when the heat transfer gas is being supplied to the gap.

[0045] Hereinafter, with reference to FIG. 4, the gas supply sequence in the operation method of the gas supply system 50 will be described. FIG. 4 is a flowchart showing a gas supply sequence according to one exemplary embodiment. In the gas supply sequence, each part of the gas supply system 50 can be controlled by the control unit 2. By executing the gas supply sequence, the heat transfer gas is supplied to the gap between the substrate support portion 11 and the back surface of the substrate W through the gas supply line 51. Also, by executing the gas supply sequence, the heat transfer gas is partially returned from the second part P2 to the first part P1 through the gas recovery line 52.

[0046] In the gas supply sequence shown in FIG. 4, first, valve V1 is opened (step 401). Next, valves V21, V22, and valve V3 are opened (step 402). Note that while the gas supply sequence is being executed, valve V4 is closed. Next, the pressure of the heat transfer gas is controlled by the pressure controller PC (step 403). During the execution of this gas supply sequence, the pump PU is operated to return a part of the heat transfer gas from the second part P2 to the first part P1. By this gas supply sequence, the heat transfer gas at a specified pressure is supplied to the gap between the substrate support portion 11 and the back surface of the substrate W. Also, the heat transfer gas is partially returned from the second part P2 to the first part P1 by the gas recovery line 52.

[0047] Hereinafter, with reference to FIG. 5, the gas stop sequence in the operation method of the gas supply system 50 will be described. FIG. 5 is a flowchart showing a gas stop sequence according to one exemplary embodiment. In the gas stop sequence, each part of the gas supply system 50 can be controlled by the control unit 2. By executing the gas stop sequence, the supply of the heat transfer gas by the gas supply system 50 is stopped.

[0048] In the gas stop sequence shown in FIG. 5, first, valves V21 and V3 are closed (step 501). Next, valve V4 is opened (step 502). Then, after waiting for a desired time (step 503), valves V22 and V4 are closed (step 504). Next, valve V1 is closed (step 505). During the execution of this gas stop sequence, the pump PU is operated to return the heat transfer gas to the first part P1. By this gas stop sequence, the supply of the heat transfer gas to the gap between the substrate support portion 11 and the back surface of the substrate W is stopped. Also, the heat transfer gas in the second part P2, the third part P3, and the gas recovery line 52 of the gas supply system 50 is returned to the first part P1 (for example, the tank TA).

[0049] According to the gas supply system 50 described above, the heat transfer gas supplied into the gap between the substrate support portion 11 and the back surface of the substrate W is returned to the first portion P1 of the gas supply line 51 and reused. Therefore, the consumption of the heat transfer gas is suppressed. Further, the gas supply line 51 and the gas recovery line 52 share the third portion P3 with each other, and the heat transfer gas is returned from the second portion P2 connected to the third portion P3 to the first portion P1. Therefore, an unintended increase in the pressure of the gas in the third portion P3 and the above-described gap can be suppressed. Further, since the gas supply line 51 and the gas recovery line 52 share the third portion P3 with each other, the gas line configuration can be simplified.

[0050] In one embodiment, when the heat transfer gas is supplied into the gap between the substrate support portion 11 and the back surface of the substrate W, a small amount of the heat transfer gas is returned from the second portion P2 to the first portion P1 via the first recovery line 521. On the other hand, when the supply of the heat transfer gas is stopped, the heat transfer gas is efficiently returned from the second portion P2 to the first portion P1 via the second recovery line 522.

[0051] Hereinafter, reference is made to FIG. 6. FIG. 6 is a diagram showing a gas supply system according to another exemplary embodiment. The gas supply system 50B shown in FIG. 6 can be employed in a substrate processing apparatus such as a plasma processing apparatus 1, for example. In the gas supply system 50B, the pressure regulator PR includes a valve V1 and a pressure gauge PM. The pressure gauge PM is configured to measure the pressure in the tank TA. The opening / closing or the opening degree of the valve V1 is controlled by the control unit 2 so that the pressure measured by the pressure gauge PM becomes a specified pressure.

[0052] Each of the other configurations of the gas supply system 50B is the same as the corresponding configuration of the gas supply system 50. The above-described operation method, gas supply sequence, and gas stop sequence can also be applied to the gas supply system 50B.

[0053] Refer to FIG. 7 below. FIG. 7 is a diagram showing a gas supply system according to yet another exemplary embodiment. The gas supply system 50C shown in FIG. 7 can be employed in a substrate processing apparatus such as, for example, the plasma processing apparatus 1. The third part P3 of the gas supply system 50C includes a valve V6. The valve V6 partially constitutes the gas flow path of the third part P3. The valve V6 may be an on-off valve or a valve whose opening degree can be adjusted. The gas supply system 50C does not include a valve V22. Each of the other configurations of the gas supply system 50C is the same as the corresponding configuration of the gas supply system 50. Also, the above-described operation method can also be applied to the gas supply system 50C.

[0054] FIG. 8 is a flowchart showing a gas supply sequence according to another exemplary embodiment. As shown in FIG. 8, in the gas supply sequence applied to the gas supply system 50C, first, the valve V1 is opened (step 801). Next, the valves V21, V3, and V6 are opened (step 802). Note that while the gas supply sequence is being executed, the valve V4 is closed. Next, the pressure of the heat transfer gas is controlled by the pressure controller PC (step 803). During the execution of this gas supply sequence, the pump PU is operated to return a part of the heat transfer gas from the second part P2 to the first part P1.

[0055] FIG. 9 is a flowchart showing a gas stop sequence according to another exemplary embodiment. As shown in FIG. 9, in the gas stop sequence applied to the gas supply system 50C, first, the valves V21, V3, and V6 are closed (step 901). Next, the valve V4 is opened (step 902). Then, after waiting for a desired time (step 903), the valve V4 is closed (step 904). Next, the valve V1 is closed (step 905). During the execution of this gas stop sequence, the pump PU is operated to return the heat transfer gas to the first part P1. According to the gas supply system 50C, during the execution of the gas stop sequence, it is suppressed that the process gas in the plasma processing chamber 10 is returned to the first part P1.

[0056] Refer to FIG. 10 below. FIG. 10 is a diagram showing a gas supply system according to yet another exemplary embodiment. The gas supply system 50D shown in FIG. 10 can be employed in a substrate processing apparatus such as the plasma processing apparatus 1, for example. In the gas supply system 50D, the gas recovery line 52 does not include the first recovery line 521 and the second recovery line 522, and provides a single gas flow path connected between the second portion P2 and the pump PU. The gas recovery line 52 includes a valve V3C whose opening degree can be adjusted. The valve V3C constitutes a part of the single gas flow path of the gas recovery line 52. Each of the other configurations of the gas supply system 50D is the same as the corresponding configuration of the gas supply system 50. Also, the above-described operation method can also be applied to the gas supply system 50D.

[0057] FIG. 11 is a flowchart showing a gas supply sequence according to yet another exemplary embodiment. As shown in FIG. 11, in the gas supply sequence applied to the gas supply system 50D, first, the valve V1 is opened (step 1101). Next, the valves V21, V22, and V3C are opened (step 1102). The opening degree of the valve V3C is set to an opening degree smaller than the fully open state in order to return a small amount of heat transfer gas from the second portion P2 to the first portion P1. Next, the pressure of the heat transfer gas is controlled by the pressure controller PC (step 1103). During the execution of this gas supply sequence, the pump PU is operated to return a part of the heat transfer gas from the second portion P2 to the first portion P1.

[0058] FIG. 12 is a flowchart showing a gas stop sequence according to yet another exemplary embodiment. As shown in FIG. 12, in the gas stop sequence applied to the gas supply system 50D, first, the valve V21 is closed (step 1202). Next, the valve V3C is opened (step 1202). The opening degree of the valve V3C is set to a higher opening degree than its opening degree during the execution of the gas supply sequence, for example, fully open. Then, after waiting for a desired time (step 1203), the valves V22 and V3C are closed (step 1204). Next, the valve V1 is closed (step 1205). During the execution of this gas stop sequence, the pump PU is operated to return the heat transfer gas to the first portion P1.

[0059] Hereinafter, refer to FIG. 13. FIG. 13 is a diagram showing a gas supply system according to yet another exemplary embodiment. The gas supply system 50E shown in FIG. 13 can be employed in a substrate processing apparatus such as the plasma processing apparatus 1, for example. The gas supply system 50E further includes a gas supply line 51E and a gas recovery line 52E.

[0060] Similar to the gas supply line 51, the gas supply line 51E is configured to supply the heat transfer gas to the gap between the substrate support portion 11 and the back surface of the substrate W. The gas supply line 51E includes a second portion P2E, a pressure controller PCE, and a third portion P3E. The gas supply line 51E shares the first portion P1 with the gas supply line 51.

[0061] The second part P2E is downstream of the first part P1. The second part P2E provides a gas flow path for the heat transfer gas. The pressure controller PCE is connected between the first part P1 and the second part P2E. The pressure controller PCE is configured to control the pressure of the heat transfer gas output downstream thereof in the gas supply line 51E. The pressure of the heat transfer gas output downstream by the pressure controller PCE is specified, for example, from the control unit 2 to the pressure controller PCE. In one embodiment, the pressure controller PCE is connected to the first part P1 via the valve V21. Further, the pressure controller PCE is connected to the second part P2E via the valve V22E. The valve V22E may be an on-off valve or a valve whose opening degree can be adjusted.

[0062] The third part P3E is downstream of the second part P2E and provides a gas flow path for the heat transfer gas. The third part P3E connects the gap between the second part P2E, the substrate support part 11, and the back surface of the substrate W to each other. In the gas supply line 51E, the heat transfer gas is supplied from the source GS to the gap between the substrate support part 11 and the back surface of the substrate W through the first part P1, the pressure controller PCE, the second part P2E, and the third part P3E.

[0063] The gas recovery line 52E is connected to the first part P1 and the second part P2E. The gas recovery line 52E includes a gas flow path connected between the first part P1 and the second part P2E. The gas recovery line 52E shares the pump PU with the gas recovery line 52. The pump PU partially constitutes the gas flow path of the gas recovery line 52 and the gas flow path of the gas recovery line 52E. The gas recovery line 52E is configured to return the heat transfer gas from the second part P2E to the first part P1. In one embodiment, the gas recovery line 52E is configured to return the gas from the second part P2E to the tank TA. The gas recovery line 52E shares the third part P3E with the gas supply line 51E.

[0064] In one embodiment, the gas recovery line 52E may include a first recovery line 521E and a second recovery line 522E. The first recovery line 521E provides a gas flow path connecting the second portion P2E and the pump PU. The first recovery line 521E further includes a valve V3E and an orifice OFE. The valve V3E and the orifice OFE partially constitute the gas flow path of the first recovery line 521E. The valve V3E may be an on-off valve or a valve with an adjustable opening degree. The orifice OFE reduces the cross-sectional area of the gas flow path of the first recovery line 521E.

[0065] The second recovery line 522E provides another gas flow path connecting the second portion P2E and the pump PU. That is, the first recovery line 521E and the second recovery line 522E are connected in parallel between the second portion P2E and the pump PU. The second recovery line 522E further includes a valve V4E. The valve V4E partially constitutes the gas flow path of the second recovery line 522E. The valve V4E may be an on-off valve or a valve with an adjustable opening degree. Note that the second recovery line 522E does not include an orifice. That is, the minimum cross-sectional area of the gas flow path of the second recovery line 522E is larger than the minimum cross-sectional area of the gas flow path of the first recovery line 521E.

[0066] Each of the other configurations of the gas supply system 50E is the same as the corresponding configuration of the gas supply system 50. Also, the above-described operation method can also be applied to the gas supply system 50E. Specifically, the operation method includes a step of supplying a heat transfer gas into the gap between the substrate support portion 11 and the back surface of the substrate W through the gas supply lines 51 and 51E. The operation method further includes a step of partially recovering the heat transfer gas from the second portions P2 and P2E to the first portion P1 through the gas recovery lines 52 and 52E when the heat transfer gas is being supplied into the gap.

[0067] In the gas supply sequence applied to the gas supply system 50E, each part of the gas supply system 50E can be controlled by the control unit 2. When the gas supply sequence is executed, the heat transfer gas is supplied through the gas supply lines 51 and 51E to the gap between the substrate support portion 11 and the back surface of the substrate W. Also, when the gas supply sequence is executed, the heat transfer gas is partially returned from the second parts P2 and P2E to the first part P1 through the gas recovery lines 52 and 52E.

[0068] FIG. 14 is a flowchart showing a gas supply sequence according to yet another exemplary embodiment. As shown in FIG. 14, in the gas supply sequence applied to the gas supply system 50E, first, the valve V1 is opened (step 1401). Next, the valves V21, V22, V22E, V3, and V3E are opened (step 1402). Note that the valves V4 and V4E are closed while the gas supply sequence is being executed. Next, the pressure of the heat transfer gas is controlled by the pressure controllers PC and PCE (step 1403). During the execution of this gas supply sequence, the pump PU is operated to return a part of the heat transfer gas from the second parts P2 and P2E to the first part P1. By this gas supply sequence, the heat transfer gas at a specified pressure is supplied to the gap between the substrate support portion 11 and the back surface of the substrate W. Also, the heat transfer gas is partially returned from the second parts P2 and P2E to the first part P1 through the gas recovery lines 52 and 52E.

[0069] In the gas stop sequence applied to the gas supply system 50E, each part of the gas supply system 50E can be controlled by the control unit 2. When the gas stop sequence is executed, the supply of the heat transfer gas by the gas supply system 50E is stopped.

[0070] FIG. 15 is a flowchart showing a gas stop sequence according to yet another exemplary embodiment. As shown in FIG. 15, in the gas stop sequence applied to the gas supply system 50E, first, valves V21, V3, and V3E are closed (step 1501). Next, valves V4 and V4E are opened (step 1502). After waiting for a desired time (step 1503), valves V22, V22E, V4, and V4E are closed (step 1504). Then, valve V1 is closed (step 1505). During the execution of this gas stop sequence, the pump PU is operated to return the heat transfer gas to the first portion P1. By this gas stop sequence, the supply of the heat transfer gas to the gap between the substrate support portion 11 and the back surface of the substrate W is stopped. Also, the heat transfer gas in the second portions P2 and P2E, the third portions P3 and P3E of the gas supply system 50, and the gas recovery lines 52 and 52E is returned to the first portion P1 (e.g., the tank TA).

[0071] Next, refer to FIG. 16. FIG. 16 is a diagram showing a gas supply system according to yet another exemplary embodiment. The gas supply system 50F shown in FIG. 16 is different from the gas supply system 50 in that it further includes a booster PI, a filter FT, and a check valve CV. The booster PI, the filter FT, and the check valve CV are connected between the pump PU and the first portion P1 (e.g., the tank TA). The pump PU may be a turbo molecular pump. Note that each of the gas supply systems according to the various embodiments described above may also further include a booster PI, a filter FT, and a check valve CV, similar to the gas supply system 50F.

[0072] The booster PI boosts the gas recovered by the gas recovery line 52. The gas boosted by the booster PI is returned to the first part P1 (for example, the tank TA). The booster PI may be a dry pump, a compressor, or the like. The check valve CV is provided to prevent the backflow of gas from the gas supply line 51 to the gas recovery line 52. The filter FT is connected between the check valve CV and the booster PI. The filter FT is configured to capture and remove components other than the heat transfer gas. The components removed by the filter FT may include the oil of the booster PI, mechanical dust in the exhaust system, dust from the back surface of the substrate and the substrate support (for example, the electrostatic chuck), degassing from inside the pipe, and residual gas in the chamber.

[0073] As described above, various exemplary embodiments have been described. However, without being limited to the above-described exemplary embodiments, various additions, omissions, substitutions, and changes may be made. Also, it is possible to form other embodiments by combining elements in different embodiments.

[0074] For example, the gas supply systems of the various embodiments described above may be employed in other substrate processing apparatuses other than the plasma processing apparatus.

[0075] Also, although the gas supply system 50E includes two gas supply lines and two gas recovery lines, in other embodiments, the gas supply system may include three or more gas supply lines and three or more gas recovery lines.

[0076] Also, an exhaust device may be connected to the second recovery line 522 between the valve V4 and the pump PU. Further, at least one another gas supply line may be connected to the gas flow path of the gas supply line 51 between the valve V21 and the pressure controller PC. The at least one another gas supply line is provided to supply a heat transfer gas to the gap between the substrate support portion of at least one another substrate processing apparatus and the back surface of the substrate. The at least one another gas supply line may include a pressure controller, a valve, a second portion, and a third portion, similar to the gas supply line 51. The pressure controller, the valve, the second portion, and the third portion in the at least one another gas supply line are connected between the valve V21 and the gap between the substrate support portion of at least one another substrate processing apparatus and the back surface of the substrate. Also, between the second portion and the pump PU in the at least one another gas supply line, a first recovery line and a second recovery line may be connected, similar to the gas recovery line 52.

[0077] Here, various exemplary embodiments included in the present disclosure are described in the following [E1] to [E16].

[0078] [E1] A gas supply line, A gas recovery line, Comprising, The gas supply line supplies a heat transfer gas to a gap between a substrate support portion and the back surface of the substrate, The gas supply line, A first portion, A second portion downstream of the first portion, Configured to adjust the pressure of the heat transfer gas, a pressure controller connected between the first portion and the second portion, A third portion connecting the second portion and the gap, Including, The gas recovery line is connected to the first portion and the second portion, includes a pump connected between the first portion and the second portion, shares the third portion with the gas supply line, and is configured to return the heat transfer gas from the second portion to the first portion. Gas supply system.

[0079] [E2] The gas recovery line, A gas flow path connected between the second portion and the pump, An orifice that reduces the cross-sectional area of the gas flow path, The gas supply system according to E1, further comprising.

[0080] [E3] The gas recovery line further includes another gas flow path connected between the second portion and the pump, the gas supply system according to E2.

[0081] [E4] The gas recovery line, A gas flow path connected between the second portion and the pump, A valve capable of adjusting the opening degree of the gas flow path, The gas supply system according to E1, further comprising.

[0082] [E5] When the heat transfer gas is supplied from the gas supply line to the gap, the opening degree of the valve is set to an opening degree smaller than fully open, the gas supply system according to E4.

[0083] [E6] The third portion includes a valve connected between the second portion and the substrate support portion, the gas supply system according to any one of E1 to E5.

[0084] [E7] The first portion includes a tank for storing the heat transfer gas, The gas recovery line is configured to return the heat transfer gas to the tank, The gas supply system according to any one of E1 to E6.

[0085] [E8] The gas supply system according to any one of E1 to E7, further comprising a pressure regulator configured to adjust the pressure of the heat transfer gas in a portion upstream of the pressure controller in the gas supply line.

[0086] [E9] The gas supply system further includes a pressure regulator configured to adjust the pressure of the heat transfer gas in the upstream portion of the pressure controller in the gas supply line. The pressure regulator includes a pressure gauge configured to measure the pressure of the heat transfer gas in the tank, and a valve connected between the heat transfer gas source and the first portion, the valve being opened and closed according to the pressure measured by the pressure gauge. The gas supply system according to E7.

[0087] [E10] The pressure regulator sets the pressure in the upstream portion of the pressure controller in the gas supply line to a pressure higher than the required supply pressure of the pressure controller, as described in E8 or E9.

[0088] [E11] Another gas supply line for supplying the heat transfer gas to the gap, including the first portion, another second portion downstream of the first portion, another pressure controller configured to adjust the pressure of the heat transfer gas, and connected between the first portion and the another second portion, and another third portion connecting the another second portion and the gap. Another gas recovery line connecting the first portion and the another second portion, including the pump connected between the first portion and the another second portion, and configured to return the heat transfer gas from the another second portion to the first portion. The gas supply system according to any one of E1 to E10, further comprising

[0089] [E12] The gas recovery line is connected between the pump and the first portion, and further includes a booster configured to increase the pressure of the gas recovered from the second portion, as described in any one of E1 to E11.

[0090] [E13] The gas recovery line further includes a check valve connected between the pump and the first portion, as described in any one of E1 to E12.

[0091] [E14] The gas recovery line further includes a filter connected between the pump and the first portion, as described in any one of E1 to E13.

[0092] [E15] A substrate support portion configured to support a substrate placed thereon, The gas supply system according to any one of E1 to E14, configured to supply a heat transfer gas to a gap between the substrate support portion and the back surface of the substrate. A substrate processing apparatus comprising

[0093] [E16] A method of operating the gas supply system according to any one of E1 to E14, A step of supplying the heat transfer gas to the gap through the gas supply line; A step of partially recovering the heat transfer gas from the second portion to the first portion through the gas recovery line when the heat transfer gas is being supplied to the gap; An operation method including the above steps.

[0094] From the above description, it will be understood that the various embodiments of the present disclosure are described herein for the purpose of illustration and that various changes can be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, and the true scope and spirit are indicated by the appended claims.

Description of Reference Numerals

[0095] 1... Plasma processing apparatus, 2... Control unit, 11... Substrate support unit, 50... Gas supply system, 51... Gas supply line, P1... First part, P2... Second part, P3... Third part, PC... Pressure controller, 52... Gas recovery line, PU... Pump.

Claims

1. A gas supply line, A gas recovery line, Comprising: The gas supply line supplies a heat transfer gas to a gap between a substrate support portion and the back surface of the substrate, The gas supply line, A first portion, A second portion downstream of the first portion, Is configured to adjust the pressure of the heat transfer gas, and a pressure controller connected between the first portion and the second portion, A third portion connecting the second portion and the gap, Including, The gas recovery line, A pump, A first gas flow path connecting the pump and the second portion to each other on the intake side of the pump, A second gas flow path connecting the pump and the second portion to each other in parallel with the first gas flow path on the intake side of the pump, Another gas flow path connecting the pump and the first portion to each other on the exhaust side of the pump, An orifice for reducing the cross-sectional area of the first gas flow path, Including, sharing the third portion with the gas supply line, and configured to return the heat transfer gas from the second portion to the first portion, Gas supply system.

2. The first portion includes a tank for storing the heat transfer gas, The gas recovery line is configured to return the heat transfer gas to the tank, The gas supply system according to claim 1.

3. The gas supply line further includes a pressure regulator configured to adjust the pressure of the heat transfer gas in a portion upstream of the pressure controller, The pressure regulator, A pressure gauge configured to measure the pressure of the heat transfer gas in the tank, A valve connected between the source of the heat transfer gas and the first portion, and opened and closed according to the pressure measured by the pressure gauge, the valve, Including, the gas supply system according to claim 2.

4. A gas supply line, A gas recovery line, Comprising: The gas supply line supplies a heat transfer gas to a gap between a substrate support portion and the back surface of the substrate, The gas supply line, A first portion, A second portion downstream of the first portion, Is configured to adjust the pressure of the heat transfer gas, and a pressure controller connected between the first portion and the second portion, A third portion connecting the second portion and the gap, Including, The gas recovery line, A pump, A gas flow path connecting the pump and the second portion to each other on the intake side of the pump, Another gas flow path connecting the pump and the first part to each other on the exhaust side of the pump; including, sharing the third part with the gas supply line, and configured to return the heat transfer gas from the second part to the first part; the first part includes a tank for storing the heat transfer gas; the gas recovery line is configured to return the heat transfer gas to the tank; further comprising a pressure regulator configured to adjust the pressure of the heat transfer gas in the part upstream of the pressure controller in the gas supply line; the pressure regulator; a pressure gauge configured to measure the pressure of the heat transfer gas in the tank; a valve connected between the source of the heat transfer gas and the first part, and opened and closed according to the pressure measured by the pressure gauge; including; a gas supply system.

5. The gas supply system according to claim 4, wherein the gas recovery line further includes an orifice that reduces the cross-sectional area of the gas flow path connecting the pump and the second part to each other.

6. The gas supply system according to claim 4, wherein the gas recovery line further includes a valve capable of adjusting the opening degree of the gas flow path.

7. The gas supply system according to claim 6, wherein when the heat transfer gas is supplied from the gas supply line to the gap, the opening degree of the valve is set to an opening degree smaller than the fully open state.

8. The gas supply system according to any one of claims 1 to 7, wherein the third part includes a valve connected between the second part and the substrate support part.

9. The gas supply system according to any one of claims 1 to 7, further comprising a pressure regulator configured to adjust the pressure of the heat transfer gas in the part upstream of the pressure controller in the gas supply line.

10. The gas supply system according to claim 9, wherein the pressure regulator sets the pressure in the part upstream of the pressure controller in the gas supply line to a pressure higher than the required supply pressure of the pressure controller.

11. Another gas supply line for supplying the heat transfer gas to the gap; the first part; another second part downstream of the first part; configured to adjust the pressure of the heat transfer gas, and another pressure controller connected between the first part and the another second part; Another third part connecting the other second part and the gap, including the other gas supply line; Another gas recovery line connecting the first part and the other second part to each other, the pump; A gas flow path connecting the pump and the other second part to each other on the intake side of the pump, Another gas flow path connecting the pump and the first part to each other on the exhaust side of the pump, Including, the other gas recovery line configured to return the heat transfer gas from the other second part to the first part, The gas supply system according to any one of claims 1 to 7, further comprising.

12. The gas recovery line is connected between the pump and the first part, and further includes a booster configured to boost the gas recovered from the second part in the other gas flow path. The gas supply system according to any one of claims 1 to 7.

13. The gas recovery line further includes a check valve connected between the pump and the first part in the other gas flow path. The gas supply system according to any one of claims 1 to 7.

14. The gas recovery line further includes a filter connected between the pump and the first part in the other gas flow path. The gas supply system according to any one of claims 1 to 7.

15. A substrate support portion configured to support a substrate placed thereon, The gas supply system according to any one of claims 1 to 7, the gas supply system configured to supply a heat transfer gas to a gap between the substrate support portion and the back surface of the substrate, A substrate processing apparatus comprising.

16. A method of operating the gas supply system according to any one of claims 1 to 7, Supplying the heat transfer gas to the gap by the gas supply line; Partially recovering the heat transfer gas from the second part to the first part by the gas recovery line when the heat transfer gas is being supplied to the gap; An operation method including.

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