Plasma processing device

Abstract

This plasma processing device comprises: a plasma processing chamber; a plasma generation unit that generates plasma in the plasma processing chamber and includes a first matching unit; a substrate support part that is disposed in the plasma processing chamber and includes a base and an electrostatic chuck; an edge ring disposed on a ring support surface of the electrostatic chuck; a direct-current power supply that supplies direct-current power to the edge ring; a bias electrode provided to the substrate support part; a second matching unit electrically connected to the bias electrode; a bias power supply electrically connected to the second matching unit; and a control unit. The control unit performs control so as to stop matching processing in the first matching unit and the second matching unit in a period in which the direct-current power supply does not supply direct-current power to the edge ring.

Description

Plasma processing equipment

[0001] The present disclosure relates to a plasma processing apparatus.

[0002] Japanese Patent Application Laid-Open No. 2003-144222 discloses a technique for applying a negative DC voltage to an edge ring in order to control the tilt angle at the edge region of a substrate during plasma processing.

[0003] Japanese Patent Application Laid-Open No. 2023-043151

[0004] The present disclosure provides a technique for stably operating a matching box.

[0005] According to one aspect of the present disclosure, there is provided a plasma processing apparatus comprising: a plasma processing chamber; a plasma generation unit that generates plasma in the plasma processing chamber and includes a first matcher; a substrate support unit disposed in the plasma processing chamber and including a base and an electrostatic chuck; an edge ring disposed on a ring support surface of the electrostatic chuck; a DC power supply that supplies DC power to the edge ring; a bias electrode provided on the substrate support unit; a second matcher electrically connected to the bias electrode; a bias power supply electrically connected to the second matcher; and a controller, wherein the controller controls the first matcher and the second matcher to stop matching processes during a period when the DC power supply is not applying DC power to the edge ring.

[0006] The present disclosure provides a technique for stably operating a matching box.

[0007] FIG. 1 is a diagram illustrating the configuration of a plasma processing system including a plasma processing apparatus according to this embodiment. FIG. 2 is a diagram illustrating the configuration of the plasma processing apparatus according to this embodiment. FIG. 3 is a diagram illustrating the process in the plasma processing apparatus according to this embodiment. FIG. 4 is a diagram illustrating the process in the plasma processing apparatus according to this embodiment. FIG. 5 is a diagram illustrating the process when plasma is generated by a continuous wave in the plasma processing apparatus according to this embodiment. FIG. 6 is a diagram illustrating the process when plasma is generated by a pulse wave in the plasma processing apparatus according to this embodiment.

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In this specification and the drawings, substantially identical components are designated by the same reference numerals, and redundant description will be omitted. To facilitate understanding, the scale of each part in the drawings may differ from the actual scale. Directions such as parallel, right-angled, orthogonal, horizontal, vertical, up / down, left / right, and the like are permitted to a degree that does not impair the effects of the embodiments. The shape of corners is not limited to right angles and may be rounded. Parallel, right-angled, orthogonal, horizontal, and vertical may include approximately parallel, approximately right-angled, approximately orthogonal, approximately horizontal, and approximately vertical.

[0009] An example of the configuration of a plasma processing system will be described below: Fig. 1 is a diagram illustrating the configuration of a plasma processing system including a plasma processing apparatus 1, which is an example of a plasma processing apparatus according to this embodiment.

[0010] The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, an exhaust system 40, and a bias supply 60. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one processing gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the plasma processing chamber 10 housing.

[0011] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 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 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base 111A and an electrostatic chuck 111B. The base 111A includes a conductive member. The conductive member of the base 111A functions as a lower electrode, which is a bias electrode. The electrostatic chuck 111B is disposed on the base 111A. The upper surface of the electrostatic chuck 111B has a 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 (hereinafter referred to as the edge ring 112). Although not shown, the substrate support 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 111B, the ring assembly 112, and the substrate 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. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a. Note that a bias electrode may be provided inside the electrostatic chuck 111B instead of the base 111A.

[0012] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process 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 multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0013] 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 process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0014] 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. This causes plasma to be formed from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more process gases in the plasma processing chamber 10. Furthermore, supplying a bias RF signal to the conductive member of the substrate support 11 generates a bias potential on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0015] In one embodiment, the RF power supply 31 includes a first RF generator 31a and a second RF generator 31b. The first RF generator 31a is coupled to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13 via at least one impedance matching circuit (an example of a first matching box) 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 generator 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13. The second RF generator 31b is coupled to the conductive members of the substrate support 11 via at least one impedance matching circuit (an example of a second matching box) and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a frequency lower than that of 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 generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to the conductive members of the substrate support 11. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0016] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first bias DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, at least one of the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0017] The exhaust system 40 may be connected to, for example, a gas exhaust 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 regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0018] The bias supply unit 60 supplies DC power to the edge ring 112. The bias supply unit 60 includes a DC power supply 61 and a filter 62. The DC power supply 61 supplies a constant negative voltage relative to the bias voltage to the edge ring 112. In order for the DC power supply 61 to supply a constant negative voltage relative to the bias voltage to the edge ring 112, the bias supply unit 60 stops the supply of bias power and measures the bias voltage. The filter 62 attenuates high-frequency signals from the power supply 30 so that they are not input to the DC power supply 61.

[0019] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 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 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), 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).

[0020] A plasma processing apparatus according to this embodiment will be described. The plasma processing apparatus according to this embodiment includes a plasma processing chamber, a plasma generation unit that generates plasma in the plasma processing chamber and includes a first matcher, and a substrate support unit disposed in the plasma processing chamber and including a base and an electrostatic chuck. The plasma processing apparatus according to this embodiment also includes an edge ring 112 disposed on the ring support surface of the electrostatic chuck, a DC power supply that supplies DC power to the edge ring 112, a bias electrode disposed on the substrate support unit, and a second matcher electrically connected to the bias electrode. The plasma processing apparatus according to this embodiment also includes a bias power supply electrically connected to the second matcher, and a controller. The controller of the plasma processing apparatus according to this embodiment controls the first matcher and the second matcher to stop matching processes during periods when the DC power supply is not applying DC power to the edge ring 112.

[0021] The details of the plasma processing apparatus according to this embodiment will be described with reference to the drawings. Fig. 2 is a diagram illustrating the configuration of a plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment.

[0022] The plasma processing apparatus 1 includes a plasma processing chamber 110 , a high frequency power supply 130 , a matching box 135 , a synchronization control unit 150 , and a DC power supply 160 .

[0023] The high frequency power supply 130 supplies high frequency power RF to the plasma processing chamber 110 via a matching box 135. The high frequency power RF is, for example, a high frequency power for plasma generation or a high frequency power for bias. That is, the high frequency power supply 130 is, for example, a power supply representing a high frequency power supply for plasma generation (first RF generating unit 31a in FIG. 1) or a high frequency power supply for bias (second RF generating unit 31b in FIG. 1). As described above, the plasma processing chamber 110 includes a substrate support 11.

[0024] The matching box 135 performs impedance matching so that the high frequency power RF supplied to the plasma processing chamber 110 is not reflected and returned to the high frequency power supply 130. The matching box 135 is configured with, for example, an inductor, a capacitor, etc. Note that the matching box 135 may also be configured with a transistor, etc.

[0025] The matching box 135 is connected to, for example, a plasma generating high frequency power supply (first RF generating unit 31a in FIG. 1) or a bias high frequency power supply (second RF generating unit 31b in FIG. 1).

[0026] A DC power supply 160 (DC power supply 61 in FIG. 1) supplies DC power to the edge ring 112 in the plasma processing chamber 110 .

[0027] The synchronization control unit 150 adjusts the timing of the matching process in the matching unit 135 and the supply of DC power from the DC power supply 160. In other words, the synchronization control unit 150 controls the matching unit 135 and the DC power supply 160 so that they operate in synchronization. The synchronization control unit 150 outputs a control signal SS1 to the matching unit 135 in order to control the matching process in the matching unit 135. The synchronization control unit 150 also outputs a control signal SS2 to the DC power supply 160 in order to control the supply of DC power from the DC power supply 160. Note that synchronization does not only refer to a case where the control timing of the matching unit 135 and the control timing of the DC power supply 160 are the same, but also includes a case where the control timing of the matching unit 135 and the control timing of the DC power supply 160 are shifted (offset) by a certain time.

[0028] The processing by the synchronization control unit 150 is executed by, for example, the control unit 2 in FIG.

[0029] Next, a description will be given of the processing in the synchronization control unit 150. Fig. 3 is a diagram for explaining the processing in the plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment.

[0030] The horizontal axis in Fig. 3 represents time, and the vertical axis represents voltage. The intersection of the voltage level on the vertical axis with the horizontal axis represents the reference potential. The reference potential is, for example, the ground level. DC in Fig. 3 represents the voltage of the direct current power DC supplied from the direct current power supply 160. SS1 in Fig. 3 represents the control signal SS1 output from the synchronization control unit 150 to the matching unit 135. SS2 in Fig. 3 represents the control signal SS2 output from the synchronization control unit 150 to the direct current power supply 160. Note that the control signal SS1 is an example of a first control signal, and the control signal SS2 is an example of a second control signal.

[0031] The direct current power DC is supplied from a direct current power supply 160. The direct current power supply 160 supplies the direct current power DC to the edge ring 112 in the plasma processing chamber 110 based on a control signal SS2 output from the synchronization control unit 150.

[0032] When the control signal SS2 is at a high level, that is, during period D in Fig. 3, the DC power supply 160 stops supplying the DC power DC to the plasma processing chamber 110. Therefore, as shown by DC in Fig. 3, the DC power DC supplied to the plasma processing chamber 110 during period A is stopped during period B.

[0033] The plasma processing apparatus 1 measures the self-bias voltage of the edge ring 112 while the supply of direct current power DC from the direct current power supply 160 is stopped (periods B and D).

[0034] The synchronization control unit 150 sets the control signal SS1 to a high level so that the matching device 135 performs matching processing after a certain time (time F) has elapsed (after the offset time has elapsed) since the state in which the application of direct current power DC to the edge ring 112 was stopped (time E). The matching device 135 performs matching operation during the time (time G) when the control signal SS1 is at a high level. Note that during the times (times E, F, and H) when the control signal SS1 is at a low level, the matching device 135 stops matching processing and operates at a constant impedance. That is, the matching device 135 monitors the impedance during period C and performs matching processing.

[0035] The synchronization control unit 150 repeats the above process at each of the times E, F, G, and H, with time TC, which is the sum of time E, time F, time G, and time H, being one cycle.

[0036] The processing performed by the plasma processing apparatus will be described in more detail below. Fig. 4 is a diagram illustrating the processing performed by the plasma processing apparatus 1, which is an example of the plasma processing apparatus according to this embodiment.

[0037] 4, the horizontal axis represents time and the vertical axis represents voltage. Z in FIG. 4 represents the impedance in matching box 135. DC in FIG. 4 represents the voltage of direct-current power DC supplied from direct-current power supply 160.

[0038] The symbols A, B, E, F, G, and H in FIG. 4 correspond to the symbols in FIG.

[0039] In the plasma processing apparatus 1, during a period Pn indicated by hatching, the matching process in the matching box 135 is stopped. That is, the synchronization control unit 150 in the plasma processing apparatus 1 stops the matching process in the matching box 135 at least during a period in which the DC power supply 160 does not apply DC power DC to the edge ring 112 in the plasma processing chamber 110. The synchronization control unit 150 controls, for example, the matching processes in the first matching box connected to the plasma generation high-frequency power supply (first RF generating unit 31a in FIG. 1 ) and the second matching box connected to the bias high-frequency power supply (second RF generating unit 31b in FIG. 1 ) to be stopped.

[0040] The synchronization control unit 150 then controls the matching circuit 135 to execute matching processing after a certain time (time F) has elapsed (after the offset time has elapsed) from the period Pa (time G interval), i.e., from the state in which the DC power DC is stopped (time E), i.e., after the margin period has elapsed. In this embodiment, the period Pa is 1000 μsec. Furthermore, the time H is 1000 μsec, the time E is 300 μsec, and the time F is 7700 μsec. In other words, the period Pn is 9000 μsec. However, the values ​​of the period Pa, the period Pn, the time H, the time E, and the time F are not limited to these, and optimal values ​​can be selected depending on the conditions of the plasma processing. Furthermore, the certain time (time F) and / or the certain time (time H) may not be provided. In other words, the margin period may not be provided. The synchronization control unit 150 controls, for example, to perform matching processing in at least one of the first matching box connected to the high-frequency power supply for plasma generation (first RF generating unit 31a) and the second matching box connected to the high-frequency power supply for bias (second RF generating unit 31b).

[0041] A more specific process will be described. First, a case where high frequency power is supplied in the form of a continuous wave will be described. Fig. 5 is a diagram illustrating a process for generating plasma in the form of a continuous wave in a plasma processing apparatus 1, which is an example of a plasma processing apparatus according to this embodiment.

[0042] The horizontal axis in Fig. 5 represents time, and the vertical axis represents voltage. RF in Fig. 5 represents the voltage of the high frequency power RF supplied from the high frequency power supply 130. In Fig. 5, the high frequency power supply 130 continuously supplies RF power. That is, in Fig. 5, the control unit 2 of the plasma processing apparatus 1 generates plasma using a continuous wave. DC in Fig. 5 represents the voltage of the direct current power DC supplied from the direct current power supply 160. SS1 in Fig. 5 represents the control signal SS1 output from the synchronization control unit 150 to the matching unit 135. SS2 in Fig. 5 represents the control signal SS2 output from the synchronization control unit 150 to the direct current power supply 160.

[0043] When high frequency power is supplied in the form of a continuous wave, the bias voltage is measured in a measurement period Ta1 shown in Fig. 5. Furthermore, matching processing of the matching box 135 is performed in a matching box monitoring period Pm1 in Fig. 5.

[0044] Next, a case where high frequency power is supplied in the form of a pulse wave will be described. Fig. 6 is a diagram illustrating a process for generating plasma using a pulse wave in a plasma processing apparatus 1, which is an example of a plasma processing apparatus according to this embodiment.

[0045] The horizontal axis in Fig. 6 represents time, and the vertical axis represents voltage. RF in Fig. 6 represents the voltage of the high frequency power RF supplied from the high frequency power supply 130. In Fig. 6, the high frequency power supply 130 intermittently supplies RF power. That is, in Fig. 6, the control unit 2 of the plasma processing apparatus 1 generates plasma with a pulse wave. DC in Fig. 6 represents the voltage of the direct current power DC supplied from the direct current power supply 160. SS1 in Fig. 6 represents the control signal SS1 output from the synchronization control unit 150 to the matching unit 135. SS2 in Fig. 6 represents the control signal SS2 output from the synchronization control unit 150 to the direct current power supply 160.

[0046] When high frequency power is supplied in the form of a pulse wave, the bias voltage is measured in a measurement period Ta2 shown in Fig. 6. Furthermore, matching processing of the matching box 135 is performed in a matching box monitoring period Pm2 in Fig. 6.

[0047] The plasma processing apparatus according to this embodiment allows the matching box to operate stably. In the plasma processing apparatus, if the DC power supplied to the edge ring 112 changes, the plasma load changes, which can cause the impedance setting of the matching box to be unstable. Therefore, the plasma processing apparatus according to this embodiment stops the matching process in the first and second matching boxes during a period when the DC power source does not apply DC power to the edge ring 112, thereby allowing the matching box to operate stably.

[0048] In particular, when the measured reflection coefficient is 0.8 or higher, if matching processing is performed while the application of DC power DC to the edge ring 112 is stopped, the impedance fluctuates significantly during the transition period from application of DC power DC to its stop and / or during the transition period from its stop to application. This can cause the matching process of the matcher to be delayed and become unstable. However, according to the plasma processing apparatus of this embodiment, even when the reflection coefficient is high, such as 0.8 or higher, the matching process of the matcher can be stably operated by stopping the matching process of the matcher during the period when DC power is not being applied to the edge ring. Note that, according to the plasma processing apparatus of this embodiment, the matching process of the matcher can be stably operated even when the reflection coefficient is less than 0.8. Note that the reflection coefficient may be calculated by at least one of the first and second matchers using electrical parameters measured by at least one of the first and second matchers, or may be calculated by the control unit 2.

[0049] The plasma processing apparatus according to the present embodiment disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments can be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above-described embodiments can be configured in other ways as long as they are not inconsistent, and can be combined as long as they are not inconsistent.

[0050] The plasma processing apparatus of the present disclosure can be applied to any type of apparatus, such as a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an apparatus that generates plasma using microwaves, for example, plasma generated by a radial line slot antenna (RLSA), an electron cyclotron resonance plasma (ECR), and a helicon wave plasma (HWP).

[0051] Various exemplary embodiments included in the present disclosure are now described in the following (Appendix 1) to (Appendix 10).

[0052] a bias electrode provided on the substrate support section; a second matcher electrically connected to the bias electrode; a bias power supply electrically connected to the second matcher; and a controller, wherein the controller controls the first matcher and the second matcher to stop matching processes during a period when the DC power supply is not applying DC power to the edge ring.

[0053] (Supplementary Note 2) The plasma processing apparatus according to (Supplementary Note 1), wherein the control unit executes matching processing in at least one of the first matching box and the second matching box during a period in which the DC power supply applies DC power to the edge ring.

[0054] (Supplementary Note 3) The plasma processing apparatus described in (Supplementary Note 1) or (Supplementary Note 2), wherein the control unit executes matching processing in at least one of the first matching device and the second matching device after an offset time has elapsed since the DC power supply applied DC power to the edge ring from a state in which the DC power supply did not apply DC power to the edge ring.

[0055] (Supplementary Note 4) The plasma processing apparatus according to any one of (Supplementary Note 1) to (Supplementary Note 3), wherein the control unit supplies a first control signal to at least one of the first matching box and the second matching box, and supplies a second control signal to the DC power supply.

[0056] (Supplementary Note 5) The plasma processing apparatus according to (Supplementary Note 4), further comprising a synchronization control unit, wherein the first control signal and the second control signal are outputted in synchronization with each other from the synchronization control unit.

[0057] (Supplementary Note 6) The plasma processing apparatus according to (Supplementary Note 4) or (Supplementary Note 5), wherein at least one of the first matching box and the second matching box performs matching processing when the first control signal is supplied.

[0058] (Supplementary Note 7) The plasma processing apparatus according to any one of (Supplementary Note 4) to (Supplementary Note 6), wherein the DC power supply stops applying DC power to the edge ring when the second control signal is supplied.

[0059] (Supplementary Note 8) The plasma processing apparatus according to any one of (Supplementary Note 5) to (Supplementary Note 7), wherein the synchronization control unit outputs the first control signal after the offset time has elapsed since outputting the second control signal.

[0060] (Supplementary Note 9) The plasma processing apparatus according to any one of (Supplementary Note 1) to (Supplementary Note 8), wherein when the control unit stops the matching process in the first matching box and the second matching box, the reflection coefficient in each of the first matching box and the second matching box is 0.8 or more.

[0061] (Supplementary Note 10) The plasma processing apparatus according to (Supplementary Note 9), wherein the reflection coefficient is calculated by any one of the first matching box, the second matching box, and the control unit.

[0062] This application claims priority from basic patent application No. 2024-028047, filed with the Japan Patent Office on February 28, 2024, the entire contents of which are incorporated herein by reference.

[0063] REFERENCE SIGNS LIST 1 plasma processing apparatus 2 control unit 10 plasma processing chamber 10s plasma processing space 11 substrate support unit 30 power supply 31 RF power supply 31a first RF generating unit 31b second RF generating unit 32 DC power supply 32a first DC generating unit 32b second DC generating unit 60 bias supply unit 61 DC power supply 110 plasma processing chamber 111 main body unit 111A base 112 ring assembly 130 high frequency power supply 135 matching box 150 synchronization control unit 160 DC power supply SS1, SS2 control signal W substrate

Claims

1. A plasma processing apparatus comprising: a plasma processing chamber; a plasma generation unit that generates plasma in the plasma processing chamber and includes a first matcher; a substrate support unit that is disposed within the plasma processing chamber and includes a base and an electrostatic chuck; an edge ring that is disposed on a ring support surface of the electrostatic chuck; a DC power supply that supplies DC power to the edge ring; a bias electrode provided on the substrate support unit; a second matcher that is electrically connected to the bias electrode; a bias power supply that is electrically connected to the second matcher; and a control unit, wherein the control unit controls the first matcher and the second matcher to stop matching processes during a period when the DC power supply is not applying DC power to the edge ring.

2. The plasma processing apparatus according to claim 1, wherein the control unit executes matching processing in at least one of the first matching box and the second matching box during a period in which the DC power supply applies DC power to the edge ring.

3. The plasma processing apparatus according to claim 1 or claim 2, wherein the control unit executes matching processing in at least one of the first matching device and the second matching device after an offset time has elapsed since the DC power supply started applying DC power to the edge ring from a state in which the DC power supply was not applying DC power to the edge ring.

4. The plasma processing apparatus according to claim 3, wherein the control unit supplies a first control signal to at least one of the first matching box and the second matching box, and supplies a second control signal to the DC power supply.

5. The plasma processing apparatus according to claim 4, further comprising a synchronization control section, wherein the first control signal and the second control signal are output in synchronization with each other from the synchronization control section.

6. The plasma processing apparatus according to claim 5, wherein at least one of the first matching device and the second matching device performs matching processing when the first control signal is supplied.

7. The plasma processing apparatus according to claim 6, wherein the DC power supply stops applying DC power to the edge ring when the second control signal is supplied.

8. The plasma processing apparatus according to claim 5, wherein the synchronization control unit outputs the first control signal after the offset time has elapsed since outputting the second control signal.

9. A plasma processing apparatus according to claim 1 or claim 2, wherein when the control unit stops the matching process in the first matching box and the second matching box, the reflection coefficient in each of the first matching box and the second matching box is 0.8 or more.

10. The plasma processing apparatus according to claim 9, wherein the reflection coefficient is calculated by one of the first matching box, the second matching box, and the control unit.

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