Plasma processing device

JPWO2024142785A5Active Publication Date: 2025-06-17TOKYO ELECTRON LTD
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Patent Information

Application Number
JP2024567360
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-12-04
Filing Date
2023-12-04
Publication Date
2025-06-17
Estimated Expiration
2043-12-04

AI Technical Summary

Technical Problem

Existing plasma processing technologies face challenges in suppressing the adhesion of reaction products to areas exposed in the plasma processing space, leading to substrate contamination.

Method used

A plasma processing apparatus is designed with a configuration that includes a grounded chamber, a substrate support, an upper electrode capable of applying high-frequency power, a first insulating member to isolate the upper electrode from the chamber, and a conductive shield member made of silicon-containing material extending from the upper electrode to the chamber, ensuring the exposed area is conductive and facilitating the removal of reaction products during dry cleaning.

Benefits of technology

This configuration effectively suppresses the adhesion of reaction products to the substrate, maintaining cleanliness and preventing contamination by utilizing the conductive shield member to electrically bias and remove adhering particles.

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Abstract

The present invention provides a plasma processing device in one illustrative embodiment. This plasma processing device is provided with a chamber, a substrate-supporting part, an upper electrode, a first insulating member, and a shield member. The chamber is electrically grounded and provides a processing space for the plasma. The top electrode constitutes a portion of a top part that is provided so as to close a chamber opening located above the plasma processing space. The first insulating member constitutes a portion of the top part and is provided between the upper electrode and the chamber so as to electrically isolate the upper electrode and the chamber from each other. The shield member constitutes another portion of the top part, is formed from a conductive silicon-containing substance, and extends to the chamber from the periphery of the upper electrode. A site on the top part that is exposed to the plasma processing space is formed from a conductor including the upper electrode and the shield member.
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Description

Plasma processing equipment

[0001] TECHNICAL FIELD An embodiment of the present disclosure relates to a plasma processing apparatus.

[0002] A plasma processing apparatus is used in plasma processing of a substrate. The plasma processing apparatus disclosed in Patent Document 1 below includes a processing vessel, an upper electrode, and a shielding member. The upper electrode closes an opening in the ceiling of the processing vessel via an insulating shielding member. The upper electrode includes an inner electrode plate provided in the processing vessel and an outer electrode plate provided outside the inner electrode plate. A flow path for flowing gas is formed in the gap between the inner electrode plate and the outer electrode plate.

[0003] Japanese Patent Application Laid-Open No. 2021-077808

[0004] The present disclosure provides a technique for suppressing the adhesion of reaction products to portions exposed to a plasma processing space.

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, an upper electrode, a first insulating member, and a shield member. The chamber is electrically grounded and provides a plasma processing space. The substrate support is provided within the chamber and configured to support a substrate. The upper electrode is a part of a ceiling provided to close an opening of the chamber above the plasma processing space, is configured to be able to apply high-frequency power, and is provided above the substrate support. The first insulating member is a part of the ceiling and is provided between the upper electrode and the chamber to electrically isolate them. The shield member is another part of the ceiling, is conductive, is formed from a silicon-containing material, and extends from the periphery of the upper electrode to the chamber. The portion of the ceiling exposed to the plasma processing space is composed of a conductor including the upper electrode and the shield member.

[0006] According to the present disclosure, it is possible to suppress the adhesion of reaction products to the portions exposed to the plasma processing space.

[0007] FIG. 1 is a diagram for explaining an example of the configuration of a plasma processing system. FIG. 2 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus. FIG. 3 is a diagram for explaining a plasma processing apparatus according to one exemplary embodiment. FIG. 4 is a graph showing changes in the real part (resistance value) of the impedance of a load of a high frequency power supply according to the power level of high frequency power supplied to an upper electrode. FIG. 5 is a graph showing the relationship between plasma density and the real part (resistance value) of the impedance of a load of a high frequency power supply. FIG. 6 is a diagram for explaining a plasma processing apparatus according to another exemplary embodiment. FIG. 7 is a block diagram of a processing circuit for performing the operations described herein on a computer.

[0008] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0009] FIG. 1 is a diagram illustrating an exemplary configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0010] The plasma generating 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), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generating units may be used, including alternating current (AC) plasma generating units and direct current (DC) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Therefore, AC signals include RF (Radio Frequency) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0011] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform 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 a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). 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 local area network (LAN).

[0012] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0013] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. 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 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0014] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. 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. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0015] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a lower electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Furthermore, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0016] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0017] The substrate support 11 may also include a temperature adjustment module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a.

[0018] 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 at least one 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.

[0019] 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 at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0020] 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) to at least one lower electrode and / or at least one upper electrode. This generates a plasma 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. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0021] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to at least one lower electrode and / or at least one upper electrode 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 10 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0022] The second RF generator 31b is coupled to at least one lower electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 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 at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0023] 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 the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0024] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one period. 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.

[0025] 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.

[0026] A plasma processing apparatus according to an exemplary embodiment will be described below with reference to Figures 2 and 3. Figure 3 is a diagram showing an upper electrode and a shield member provided in the plasma processing apparatus shown in Figure 2.

[0027] 3, the sidewall 10a of the plasma processing chamber 10 has a substantially cylindrical shape. The sidewall 10a is connected to ground and has a ground potential. The upper end of the sidewall 10a is open.

[0028] The plasma processing apparatus 1 has a ceiling 14 above the plasma processing space 10s. The ceiling 14 is provided to close the opening of the plasma processing chamber 10. That is, the ceiling 14 covers and closes the opening at the upper end of the sidewall 10a. A portion of the ceiling 14 is exposed to the plasma processing space 10s.

[0029] The shower head 13, which constitutes part of the ceiling part 14, includes at least one upper electrode 13d. The upper electrode 13d is part of the ceiling part 14, is configured to be able to apply high-frequency power, and is provided above the substrate support part 11. The upper electrode 13d is electrically connected to, for example, a first RF generator 31a. The first RF generator 31a is an example of a high-frequency power source.

[0030] The upper electrode 13d includes a top plate 13e and a first support 13f. The top plate 13e has a substantially disk shape. The top plate 13e is in contact with the plasma processing space 10s. The top plate 13e is made of a conductive material such as silicon, aluminum oxide, or quartz. The top plate 13e may be formed by forming a corrosion-resistant film on the surface of a conductive member such as aluminum. The corrosion-resistant film is made of a material such as aluminum oxide or yttrium oxide.

[0031] The first support 13f is provided on the top plate 13e. The first support 13f detachably supports the top plate 13e. The first support 13f is formed of, for example, aluminum. The first support 13f provides at least one gas diffusion chamber 13b therein. The first support 13f, together with the top plate 13e, provides at least one gas inlet 13c. The at least one gas inlet 13c extends downward from the at least one gas diffusion chamber 13b and penetrates the top plate 13e.

[0032] The ceiling 14 further includes a first insulating member 41. The first insulating member 41 is a part of the ceiling 14. The first insulating member 41 is provided between the upper electrode 13d and the plasma processing chamber 10. The first insulating member 41 electrically separates the upper electrode 13d from the plasma processing chamber 10. The first insulating member 41 is provided on the outer side (the sidewall 10a side) of the upper electrode 13d. The first insulating member 41 has a substantially ring shape and extends in the circumferential direction to surround the upper electrode 13d. The first insulating member 41 is made of an insulator such as quartz.

[0033] The ceiling 14 further includes a shield member 42. The shield member 42 is another part of the ceiling 14 and is conductive. The shield member 42 is formed, for example, from a silicon-containing material. The shield member 42 extends from the periphery of the upper electrode 13d to the plasma processing chamber 10. The shield member 42 extends in the circumferential direction so as to surround the periphery of the top plate 13e. The shield member 42 has, for example, a substantially annular shape. The shield member 42 is electrically floating. That is, the shield member 42 has a floating potential that is different from the potential of the upper electrode 13d and the potential of the plasma processing chamber 10.

[0034] The portion of the ceiling 14 exposed to the plasma processing space 10s is composed of conductors, including the upper electrode 13d and the shield member 42. For example, the portion of the ceiling 14 exposed to the plasma processing space 10s is composed only of conductors. Hereinafter, the portion of the ceiling 14 exposed to the plasma processing space 10s is referred to as the "exposed portion of the ceiling 14." In the example shown in FIG. 3, the exposed portion of the ceiling 14 is composed only of the upper electrode 13d (or the top plate 13e) and the shield member 42. The shield member 42 is provided, for example, below the first insulating member 41. The shield member 42 extends so as not to expose the first insulating member 41 to the plasma processing space 10s. In the example shown in FIG. 3, the shield member 42 is provided below a portion of the first support 13f, the first insulating member 41, and a portion of the second support 43 described below.

[0035] In the plasma processing apparatus 1, the entire exposed area of ​​the ceiling part 14 is made of a conductive material. Therefore, reaction products adhering to the exposed area can be removed by an electric bias during dry cleaning. As a result, the reaction products can be prevented from adhering to the substrate W as particles.

[0036] The plasma processing chamber 10 may further include a second support 43. The second support 43 is provided outside the first insulating member 41 and above the shield member 42. A small gap is provided between the second support 43 and the shield member 42. The second support 43 is provided on the sidewall 10a of the plasma processing chamber 10. The second support 43 is electrically connected to the sidewall 10a of the plasma processing chamber 10. The potential of the second support 43 is set to ground potential. The first insulating member 41 is provided between the first support 13f of the upper electrode 13d and the second support 43. The second support 43 has a substantially ring shape and extends circumferentially to surround the first insulating member 41. The second support 43 is formed of a metal such as aluminum.

[0037] The plasma processing apparatus 1 further includes at least one second insulating member 44. The at least one second insulating member 44 is provided outside the first insulating member 41 and on the shield member 42. The at least one second insulating member 44 is interposed between the plasma processing chamber 10 and the shield member 42. In the example shown in FIG. 3, the at least one second insulating member 44 is provided so that its lower surface contacts the outer upper surface of the shield member 42. The at least one second insulating member 44 is provided between the shield member 42 and the second support 43. The at least one second insulating member 44 is, for example, a plate-shaped member having a substantially annular shape. The at least one second insulating member 44 is formed from an insulator such as insulating ceramics, quartz, or metal oxide.

[0038] The plasma processing apparatus 1 further includes at least one third insulating member 45. The at least one third insulating member 45 is provided below the shield member 42. The at least one third insulating member 45 is interposed between the plasma processing chamber 10 and the shield member 42. The shield member 42 is supported between the at least one second insulating member 44 and the at least one third insulating member 45.

[0039] 3, the at least one third insulating member 45 includes a third support 45a and a sealing member 45b. The third support 45a is provided on the sidewall 10a. The third support 45a supports the shield member 42 from below. A portion of the inner surface of the third support 45a may be exposed to the plasma processing space 10s below the ceiling 14. The sealing member 45b is provided between the shield member 42 and the third support 45a. The sealing member 45b is arranged to contact outer portions of the shield member 42 and the third support 45a. The sealing member 45b is, for example, an O-ring that separates a reduced-pressure environment including the plasma processing space 10s from an atmospheric pressure environment.

[0040] The current flow path based on the high-frequency power supplied to the upper electrode 13d can be classified into two possible paths: a first path that does not pass through the plasma, and a second path that passes through the plasma. In the first path, the current flows from the upper electrode 13d to the sidewall 10a via the shield member 42, at least one second insulating member 44, and the second support 43. In the second path, the current flows from the upper electrode 13d to the sidewall 10a via the plasma in the plasma processing space 10s. The at least one second insulating member 44 reduces the electrostatic capacitance between the shield member 42 and the second support 43, thereby increasing the impedance of the first path. The high-frequency power supplied to the upper electrode 13d is more efficiently coupled to the plasma in the plasma processing space 10s. Furthermore, the high-frequency power supplied to the upper electrode 13d is more efficiently coupled to the plasma below the shield member 42.

[0041] Whether the high-frequency power is more efficiently coupled to the plasma in the plasma processing space 10s through the second path can be determined by fluctuations in the impedance circuit (matcher) provided in the power supply 30. When the high-frequency power is more efficiently coupled to the plasma, the resistance value recognized by the impedance circuit increases as the plasma density increases, and decreases as the plasma density decreases. The resistance value here is the real part of the impedance of the load recognized by the impedance circuit.

[0042] FIG. 4 is a graph showing the change in the real part of the impedance (resistance value) of the load of the high-frequency power supply depending on the power level of the high-frequency power supplied to the upper electrode. In the graph shown in FIG. 4, the horizontal axis represents the power level (W) of the high-frequency power supplied to the upper electrode 13d, and the vertical axis represents the real part of the impedance of the load of the high-frequency power supply (first RF generation unit 31a), i.e., the resistance value (Ω). The power level (W) of the high-frequency power increases from left to right on the horizontal axis of FIG. 4. The characteristics shown in the graph of FIG. 4 were obtained when a second insulating member 44 with a thickness of 5 mm was provided between the shielding member 42 and the second support 43. The second insulating member 44 was made of quartz. The gap between the upper electrode 13d and the shielding member 42 was 0.5 mm. The graph shown in FIG. 4 shows the resistance value when the power level of the high-frequency power was changed. The impedance and its real part (resistance value) of the load of the high frequency power supply (first RF generating unit 31a) are recognized by a matching box connected between the high frequency power supply and the upper electrode 31d.

[0043] 4, the real part of the impedance of the load of the RF power supply, i.e., the resistance value, increases as the power level of the RF power increases. Furthermore, the resistance value changes linearly with the increase in the power level of the RF power. This indicates that the RF power is efficiently coupled to the plasma.

[0044] Fig. 5 is a graph showing the relationship between plasma density and the real part of the impedance (resistance value) of the load of the high-frequency power supply. In the graph shown in Fig. 5, the horizontal axis represents plasma density (S / m), and the vertical axis represents the real part of the impedance of the load of the high-frequency power supply (first RF generating unit 31a), i.e., the resistance value (Ω). The plasma density (S / m) increases from left to right on the horizontal axis of Fig. 5. Fig. 5 shows measurement results when the thickness of the second insulating member 44 was set to 5 mm, 10 mm, 15 mm, 20 mm, and 35 mm.

[0045] As shown in Figure 5, when plasma is generated, the real part of the impedance of the load of the high-frequency power supply, i.e., the resistance value, decreases as the plasma density increases. This result indicates that it is possible to identify the plasma density based on this resistance value and to control the plasma density based on this resistance value. Also, as shown in Figure 5, the resistance value changes more significantly in response to changes in plasma density as the thickness of the second insulating member 44 increases. This indicates that by using a second insulating member 44 with a greater thickness, it becomes easier to capture fluctuations in plasma density and to control the plasma density more easily.

[0046] Although various exemplary embodiments have been described above, the present invention is not limited to the above exemplary embodiments and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements of different embodiments may be combined to form other embodiments. For example, at least one of the upper electrode 13d and the shield member 42 may be electrically connected to the second DC generator 32b. The second DC generator 32b is an example of a DC power supply.

[0047] Hereinafter, a plasma processing apparatus according to another exemplary embodiment employed in the plasma processing apparatus will be described with reference to Fig. 6. Fig. 6 is a diagram for explaining a plasma processing apparatus according to another exemplary embodiment. The plasma processing apparatus 1A according to the exemplary embodiment shown in Fig. 6 differs from the plasma processing apparatus 1 in that a first insulating member 41A has a first insulating portion 46 and a second insulating portion 47. In other words, the plasma processing apparatus 1A differs from the plasma processing apparatus 1 in that the plasma processing apparatus 1A does not have the second insulating member 44 of the plasma processing apparatus 1.

[0048] The ceiling 14 includes a first insulating member 41A. The first insulating member 41A is a part of the ceiling 14. The first insulating member 41A is formed of an insulator such as quartz. The first insulating member 41A includes a first insulating portion 46. The first insulating portion 46 is provided between the upper electrode 13d and the plasma processing chamber 10. The first insulating portion 46 electrically separates the upper electrode 13d from the plasma processing chamber 10. The first insulating portion 46 is provided on the outer side (the sidewall 10a side) of the upper electrode 13d. The first insulating portion 46 has a substantially ring shape and extends circumferentially to surround the upper electrode 13d.

[0049] The second insulating portion 47 is provided outside the first insulating portion 46 and on the shield member 42. The second insulating portion 47 has, for example, a substantially ring shape and extends circumferentially to surround the first insulating portion 46. The second insulating portion 47 extends so as to protrude outward from the lower end of the first insulating portion 46. The second insulating portion 47 is interposed between the plasma processing chamber 10 and the shield member 42. In the example shown in FIG. 6 , the second insulating portion 47 is provided so that its lower surface is in contact with the outer upper surface of the shield member 42. The second insulating portion 47 is provided between the shield member 42 and the second support 43.

[0050] In this manner, in the plasma processing apparatus 1A, the first insulating member 41A having the first insulating portion 46 and the second insulating portion 47 is interposed between the upper electrode 13d and the plasma processing chamber 10, and between the plasma processing chamber 10 and the shield member 42. This reduces the number of members for insulating current, and reduces the number of steps required to install the plasma processing apparatus 1A.

[0051] A DC connection portion 48 is provided within the second support 43. The DC connection portion 48 extends from the interior of the second support 43 through the second insulating portion 47 and connects to an outer portion of the shield member 42. The outer portion of the shield member 42 is, for example, a radially outer portion of the shield member 42 that is not exposed to the plasma processing space 10s. The outer portion of the shield member 42 may be the peripheral portion of the shield member 42. The outer portion of the shield member 42 is supported by being sandwiched between the lower end of the DC connection portion 48 and at least one third insulating member 45. For example, the lower end of the DC connection portion 48 is provided directly above the sealing member 45b of at least one third insulating member 45 in the circumferential direction. The shield member 42 in the plasma processing apparatus 1A does not need to be electrically floating.

[0052] The second DC signal generated by the second DC generator 32b is applied to the shield member 42 via the DC connection portion 48. The second DC generator 32b generates a signal having a frequency of, for example, 400 kHz as the second DC signal and supplies it to the shield member 42 via the DC connection portion 48. At this time, for example, the first RF generator 31a may generate a signal having a frequency of, for example, 100 MHz as the source RF signal and supply it to the upper electrode 13d. Furthermore, at this time, the second RF generator 31b may generate a signal having a frequency of, for example, 13 MHz as the bias RF generation signal and supply it to the lower electrode 13d. In this way, even if the DC connection portion 48 is located outside the first insulating member 41A, the DC connection portion 48 penetrates the second insulating portion 47 and connects to the shield member 42, so that the second DC signal can be appropriately applied to the shield member 42.

[0053] Furthermore, the inner wall portion 10t on the inside of the sidewall 10a facing the plasma processing space 10s is made of silicon. The inner wall portion 10t can serve as a counter electrode for the shield member 42. At least a portion of the current applied to the shield member 42 flows to the sidewall 10a via the plasma in the plasma processing space 10s and the inner wall portion 10t. Because the inner wall portion 10t is made of silicon, there is no need to separately install another member (device) that serves as a counter electrode in the plasma processing space 10s. This reduces the number of steps required to install the plasma processing apparatus 1A.

[0054] Examples of processing circuits that can be used as one or more processing circuits in the plasma processing apparatus 1, such as the control unit 2, are described below. FIG. 7 is a block diagram of a processing circuit that performs the operations described herein on a computer. FIG. 7 illustrates a processing circuit 130 that can be used to control a control process on any computer. The descriptions or blocks in the flowcharts represent modules, segments, or portions of code that include one or more executable instructions for implementing specific logical functions or steps of the process. As will be understood by those skilled in the art, other examples having functions that can be performed in a different order than that shown or described, such as substantially concurrently or in reverse order, depending on the functionality involved, are included within the scope of exemplary embodiments of the present disclosure. The various elements, features, and processes described herein may be used independently of each other or combined in various ways. All conceivable combinations and subcombinations are within the scope of the present disclosure.

[0055] In Figure 7, processing circuitry 130 includes a CPU 1200 that performs one or more of the control processes described above and / or below. Process data and instructions may be stored in memory 1202. These process data and instructions may be stored on a storage medium disk 1204, such as a hard disk drive (HDD) or a portable storage medium, or may be stored remotely. Furthermore, the claimed disclosure is not limited by the form of computer-readable medium on which instructions for processes according to the present invention are stored. For example, these instructions may be stored on a CD, DVD, flash memory, RAM, ROM, PROM, EPROM, EEPROM, hard disk, or any other information processing device, such as a server and / or computer, with which processing circuitry 130 communicates.

[0056] Furthermore, the claimed disclosure may be provided as a utility application, a background daemon, a component of an operating system, or a combination thereof, and may execute in conjunction with CPU 1200 and an operating system known to those skilled in the art, such as Microsoft Windows, UNIX, Solaris, LINUX, Apple MAC-OS, etc.

[0057] The hardware elements that make up the processing circuit 130 can be realized by various circuit elements. Furthermore, each function of the above-described embodiments can be implemented by a circuit including one or more processing circuits. As shown in FIG. 7, the processing circuit includes a specifically programmed processing unit, such as a processing unit (CPU) 1200. The processing circuit also includes devices such as application specific integrated circuits (ASICs) or conventional circuit components configured to perform the described functions.

[0058] 7, processing circuitry 130 includes a CPU 1200 that performs the processes described above. Processing circuitry 130 may be a general-purpose computer or a specialized machine. In one embodiment, processing circuitry 130 functions as a specialized machine when processing device 1200 is programmed to control plasma generation unit 12 and gas supply unit 20 (particularly when performing any of the processes described in FIGS. 1 through 6).

[0059] Alternatively or additionally, CPU 1200 may be implemented on an FPGA, ASIC, PLD, or using discrete logic circuitry, as will be appreciated by those skilled in the art. Furthermore, CPU 1200 may be implemented as multiple processing units cooperating to perform in parallel the instructions of the processes of the present invention described above.

[0060] 7 also includes a network controller 1206, such as an Intel Ethernet PRO network interface card from Intel Corporation of America, for interfacing with a network 1228. As can be appreciated, the network 1228 may be a public network, such as the Internet, a private network, such as a LAN or WAN, or any combination thereof, and may include sub-networks, such as a PSTN or ISDN. The network 1228 may also be wired, such as an Ethernet network, or wireless, such as a cellular network, including EDGE, 3G, and 4G wireless cellular systems. The wireless network may also be Wi-Fi, Bluetooth, or any other known form of wireless communication.

[0061] The processing circuitry 130 further includes a display device controller 1208, such as a graphics card or graphics adapter, for interfacing with a display device 1210, such as a monitor. A general-purpose I / O interface 1212 interfaces with a keyboard and / or mouse 1214 and a touch panel 1216, which may be integral with or separate from the display device 1210. The general-purpose I / O interface also connects to various peripheral devices 1218, such as printers and scanners.

[0062] The storage controller 1224 is connected to the storage media disk 1204 via a communication bus 1226, such as ISA, EISA, VESA, PCI, etc., and all components of the processing circuit 130 are connected to each other. The display device 1210, keyboard and / or mouse 1214, and the general features and functions of the display device controller 1208, storage controller 1224, network controller 1206, audio controller 1220, and general purpose I / O interface 1212 are not described herein for the sake of brevity, as they are well known.

[0063] The exemplary circuit elements described in this disclosure may be substituted with other elements and may have different structures than the examples described herein. Furthermore, circuits configured to implement the features described herein may be implemented in multiple circuit units (e.g., chips), or these features may be combined into the circuitry of a single chipset.

[0064] The functions and features described herein may also be performed by various distributed components on a system. For example, one or more processing devices may perform the functions of these systems, where the processing devices are distributed across multiple components communicating within a network. Distributed components may include various human interface and communication devices (e.g., display monitors, smartphones, tablets, personal digital assistants (PDAs)), as well as one or more client and server machines that can share processing. The network may be a private network, such as a LAN or WAN, or a public network, such as the Internet. Input to the system may be received directly by a user or remotely in real time or as a batch process. Furthermore, portions of the embodiments may be implemented on modules or hardware other than those described above. Accordingly, other embodiments are within the scope of the claims.

[0065] Various exemplary embodiments included in the present disclosure are now described in [E1] to [E9] below.

[0066] [E1] A plasma processing apparatus comprising: a chamber that is electrically grounded and provides a plasma processing space; a substrate support portion provided within the chamber and configured to support a substrate; an upper electrode that is a part of a ceiling portion provided to close an opening of the chamber above the plasma processing space, the upper electrode being configured to be able to apply high-frequency power and provided above the substrate support portion; a first insulating member that is a part of the ceiling portion and provided between the upper electrode and the chamber to electrically separate the upper electrode from the chamber; and a shielding member that is another part of the ceiling portion, the shielding member having conductivity and being formed from a silicon-containing material and extending from a periphery of the upper electrode to the chamber, wherein a portion of the ceiling portion exposed to the plasma processing space is composed of a conductor including the upper electrode and the shielding member.

[0067] [E2] The plasma processing apparatus according to [E1], further comprising at least one second insulating member provided on the outer side of the first insulating member and on the shielding member so as to be interposed between the chamber and the shielding member.

[0068] [E3] The plasma processing apparatus according to [E2], further comprising at least one third insulating member provided below the shielding member so as to be interposed between the chamber and the shielding member, the at least one third insulating member supporting the shielding member between the at least one second insulating member and the at least one third insulating member.

[0069] [E4] The plasma processing apparatus according to [E3], wherein the at least one third insulating member is made of insulating ceramics, quartz, or metal oxide.

[0070] [E5] The plasma processing apparatus according to [E1], wherein the first insulating member has: a first insulating portion provided between the upper electrode and the chamber; and a second insulating portion provided outside the first insulating portion and on the shielding member so as to be interposed between the chamber and the shielding member.

[0071] [E6] The plasma processing apparatus according to [E5], further comprising at least one other insulating member provided below the shielding member so as to be interposed between the chamber and the shielding member, the at least one other insulating member supporting the shielding member between the second insulating portion of the first insulating member and the at least one other insulating member.

[0072] [E7] The plasma processing apparatus according to [E6], wherein the at least one third insulating member is made of insulating ceramics, quartz, or metal oxide.

[0073] [E8] The plasma processing apparatus according to any one of [E1] to [E7], further comprising a DC power supply electrically connected to at least one of the upper electrode and the shield member.

[0074] [E9] The plasma processing apparatus according to any one of [E1] to [E7], wherein the shield member is electrically floating.

[0075] [E10] The plasma processing apparatus according to any one of [E1] to [E9], further comprising a high frequency power supply configured to generate the high frequency power and electrically connected to the upper electrode.

[0076] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may 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, with the true scope and spirit being indicated by the appended claims.

[0077] 1, 1A...plasma processing apparatus, 2...control unit, 10...plasma processing chamber, 10a...side wall, 10s...plasma processing space, 11...substrate support, 12...plasma generation unit, 13...shower head, 13d...upper electrode, 13e...top plate, 13f...first support, 14...top unit, 30...power supply, 31...RF power supply, 31a...first RF generation unit, 32...DC power supply, 32b...second DC generation unit, 41, 41A...first insulating member, 42...shield member, 43...second support, 44...second insulating member, 45...third insulating member, 46...first insulating portion, 47...second insulating portion, 111...main body, 112...ring assembly, 1110...base, 1111...electrostatic chuck, W...substrate.

Claims

1. A chamber providing a plasma processing space, a substrate support portion provided in the chamber and configured to support a substrate, a part of the top portion provided above the plasma processing space to close the opening of the chamber, configured to be capable of applying high-frequency power, and an upper electrode provided above the substrate support portion, a part of the top portion, a first insulating member provided between the upper electrode and the chamber to electrically isolate the upper electrode from the chamber, another part of the top portion, a shield member having conductivity, formed from a silicon-containing material, and extending from the periphery of the upper electrode to the chamber, at least one second insulating member provided outside the first insulating member and on the shield member so as to be interposed between the chamber and the shield member, at least one third insulating member provided under the shield member so as to be interposed between the chamber and the shield member, and supporting the shield member between the at least one second insulating member and the at least one third insulating member, the at least one third insulating member, comprising, a portion of the top portion exposed to the plasma processing space is composed of a conductor including the upper electrode and the shield member, a plasma processing apparatus.

2. The plasma processing apparatus according to claim 1, wherein the at least one third insulating member is formed from insulating ceramics, quartz, or a metal oxide.

3. A chamber providing a plasma processing space, a substrate support portion provided in the chamber and configured to support a substrate, a part of the top portion provided above the plasma processing space to close the opening of the chamber, configured to be capable of applying high-frequency power, and an upper electrode provided above the substrate support portion, A first insulating member that is part of the top portion and is provided between the upper electrode and the chamber to electrically isolate the upper electrode from the chamber. A shield member that is another part of the top portion, has conductivity, is formed from a silicon-containing material, and extends from the periphery of the upper electrode to the chamber. Including The portion of the top portion that is exposed to the plasma processing space is composed of a conductor including the upper electrode and the shield member. The first insulating member A first insulating site provided between the upper electrode and the chamber. A second insulating site provided outside the first insulating site and on the shield member so as to be interposed between the chamber and the shield member. A plasma processing apparatus.

4. At least one additional insulating member provided under the shield member so as to be interposed between the chamber and the shield member, and supporting the shield member between the second insulating site of the first insulating member and the at least one additional insulating member. The plasma processing apparatus according to claim 3, further comprising the at least one additional insulating member. The plasma processing apparatus according to claim 3.

5. The plasma processing apparatus according to claim 4, wherein the at least one additional insulating member is formed from insulating ceramics, quartz, or a metal oxide.

6. The plasma processing apparatus according to any one of claims 1 to 5, further comprising a DC power source electrically connected to at least one of the upper electrode and the shield member.

7. The plasma processing apparatus according to any one of claims 1 to 5, wherein the shield member is electrically floating.

8. The plasma processing apparatus according to any one of claims 1 to 5, further comprising a high-frequency power source configured to generate the high-frequency power and electrically connected to the upper electrode.

9. The inner wall portion inside the side wall of the chamber is formed of silicon. The plasma processing apparatus according to any one of claims 1 to 5.

10. The plasma processing apparatus according to any one of claims 1 to 5, further comprising a DC power source electrically connected to a portion outside the shield member.

11. The plasma processing apparatus further comprises a DC power source electrically connected to a portion outside the shield member via a connection portion, The connection portion penetrates through the second insulating portion and is connected to a portion outside the shield member. The plasma processing apparatus according to any one of claims 3 to 5.