Plasma processing apparatus

Abstract

In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support portion, 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 upper electrode is a part of the top portion provided above the plasma processing space so as to close the opening of the chamber. The first insulating member is a part of the top portion, and is provided between the upper electrode and the chamber so as to electrically separate the upper electrode from the chamber. The shield member is another part of the top portion, has conductivity, is formed of a silicon-containing substance, and extends from the periphery of the upper electrode to the chamber. A portion of the top portion exposed to the plasma processing space is configured from a conductor including an upper electrode and a shield member.

Description

Technical Field

[0001] Embodiments of the present invention relate to a plasma processing apparatus. Background Art

[0002] A plasma processing apparatus is used to perform plasma processing on a substrate. The plasma processing apparatus disclosed in Patent Document 1 below includes a processing container, an upper electrode, and a shielding member. The upper electrode closes an opening at the top of the processing container via an insulating shielding member. The upper electrode includes an inner electrode plate disposed inside the processing container and an outer electrode plate disposed outside the inner electrode plate. A flow path for gas flow is formed in a gap between the inner electrode plate and the outer electrode plate.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-077808. Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The present invention provides a technique for suppressing the adhesion of reaction products to a portion exposed to a plasma processing space.

[0008] Technical Means for Solving the Problems

[0009] In an exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes: a chamber, a substrate support portion, an upper electrode, a first insulating member, and a shielding member. The chamber is electrically grounded and provides a plasma processing space. The substrate support portion is disposed inside the chamber and configured to support a substrate. The upper electrode is a part of the top disposed above the plasma processing space to close an opening of the chamber, configured to apply high-frequency electric power, and disposed above the substrate support portion. The first insulating member is a part of the top disposed between the upper electrode and the chamber to electrically separate the upper electrode from the chamber. The shielding member is another part of the top, having conductivity, formed of a silicon-containing material, and extending from a periphery of the upper electrode to the chamber. A portion of the top exposed to the plasma processing space is composed of a conductor including the upper electrode and the shielding member.

[0010] Advantages of the Invention

[0011] According to the present invention, it is possible to suppress the adhesion of reaction products to a portion exposed to the plasma processing space. Brief Description of the Drawings

[0012] Figure 1 A diagram for explaining a structural example of a plasma processing system.

[0013] Figure 2 This is a diagram for explaining a structural example of a capacitively coupled plasma processing apparatus.

[0014] Figure 3 This is a diagram for explaining a plasma processing apparatus of an exemplary embodiment.

[0015] Figure 4 This is a graph showing the change in the real part (resistance value) of the impedance of a high-frequency power supply load corresponding to the power level of the high-frequency electric power supplied to the upper electrode.

[0016] Figure 5 This is a graph showing the relationship between the plasma density and the real part (resistance value) of the impedance of the high-frequency power supply load.

[0017] Figure 6 This is a diagram for explaining a plasma processing apparatus of another exemplary embodiment.

[0018] Figure 7 This is a block diagram of a processing circuit for implementing the operations described in this specification on a computer. Detailed Embodiments

[0019] Hereinafter, various exemplary embodiments will be described in detail with reference to the accompanying drawings. In addition, in each of the drawings, the same or corresponding parts are denoted by the same reference numerals.

[0020] Figure 1 This is a diagram for explaining a structural example 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 portion 11, and a plasma generation portion 12. The plasma processing chamber 10 has a plasma processing space. In addition, 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 portion 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0021] The plasma generation unit 12 is configured to be able 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), or surface wave plasma (SWP), etc. In addition, various types of plasma generation units including an AC (Alternating Current) plasma generation unit and a DC (Direct Current) plasma generation unit may also be used. In one embodiment, the AC signal (AC electric power) used in the AC plasma generation unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes 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.

[0022] The control unit 2 processes computer-executable commands that cause the plasma processing apparatus 1 to perform the various processes described in the present invention. The control unit 2 is configured to be able to control the respective elements of the plasma processing apparatus 1 to perform the various steps 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 is implemented by a computer 2a, for example. The processing unit 2a1 may be configured to perform various control actions by reading a program from the storage unit 2a2 and executing the read program. The program may be stored in the storage unit 2a2 in advance, or may be obtained via a medium when needed. The obtained program is stored in the storage unit 2a2 and read and executed by the processing unit 2a1 from the storage unit 2a2. The medium may be various storage media readable by the computer 2a, or may be 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 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 also communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0023] Hereinafter, a structural example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described. Figure 2 It is a diagram for explaining a structural example of a capacitively coupled plasma processing apparatus.

[0024] 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. In addition, the plasma processing apparatus 1 includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to be able to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a showerhead 13. The substrate support unit 11 is disposed inside the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support unit 11. In one embodiment, the showerhead 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 showerhead 13, the side wall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support unit 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0025] The substrate support portion 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a central region 111a for supporting the substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of the substrate W. The annular region 111b of the main body portion 111 surrounds the central region 111a of the main body portion 111 in a top view. The substrate W is disposed on the central region 111a of the main body portion 111, and the ring assembly 112 is disposed on the annular region 111b of the main body portion 111 so as to surround the substrate W on the central region 111a of the main body portion 111. Accordingly, the central region 111a is also referred to as a substrate support surface for supporting the substrate W, and the annular region 111b is also referred to as a ring support surface for supporting the ring assembly 112.

[0026] In one embodiment, the main body portion 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 further has an annular region 111b. In addition, other components surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck and an annular insulating member, may also have an annular region 111b. In this case, the ring assembly 112 can be disposed either on the annular electrostatic chuck or the annular insulating member, or on both the electrostatic chuck 1111 and the annular insulating member. In addition, at least one RF / DC electrode coupled to an RF power supply 31 and / or a DC power supply 32 described later can 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 described later are supplied to the at least one RF / DC electrode, the RF / DC electrode is also referred to as a bias electrode. Among them, the conductive member of the base 1110 and the at least one RF / DC electrode function as a plurality of lower electrodes. In addition, the electrostatic electrode 1111b can also function as a lower electrode. Therefore, the substrate support portion 11 includes at least one lower electrode.

[0027] 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 ring is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

[0028] In addition, the substrate support portion 11 may also include a temperature adjustment module configured to be able 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 path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows in the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. In addition, the substrate support portion 11 may also include a heat transfer gas supply portion configured to be able to supply a heat transfer gas to the gap between the back surface of the substrate W and the central region 111a.

[0029] The showerhead 13 is configured to be able to introduce at least one process gas from the gas supply portion 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 a plurality of gas introduction ports 13c. The process gas supplied to the gas supply port 13a is introduced into the plasma processing space 10s from the plurality of gas introduction ports 13c through the gas diffusion chamber 13b. In addition, the showerhead 13 includes at least one upper electrode. Furthermore, in addition to the showerhead 13, the gas introduction portion may also include one or more side gas injectors (SGI: Side Gas Injector) installed in one or more openings formed in the side wall 10a.

[0030] The gas supply portion 20 may also include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply portion 20 is configured to be able to supply at least one process gas from the corresponding gas source 21 to the showerhead 13 via the corresponding flow controller 22. Each flow controller 22 may also include, for example, a mass flow controller or a pressure-controlled flow controller. Moreover, the gas supply portion 20 may also include at least one flow modulation device for modulating or pulsing the flow rate of at least one process gas.

[0031] 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 be able to supply at least one RF signal (RF electric power) to at least one lower electrode and / or at least one upper electrode. Thereby, a plasma can 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 the plasma generation unit 12. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential can be generated on the substrate W, and the ion component in the formed plasma can be introduced into the substrate W.

[0032] 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 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 electric 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 generation unit 31a may also be configured to generate a plurality of 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.

[0033] The second RF generation unit 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 electric 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 generation unit 31b is configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. Further, in each embodiment, at least one of the source RF signal and the bias RF signal may be pulsed.

[0034] In addition, 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 generation unit 32a and a second DC generation unit 32b. In one embodiment, the first DC generation unit 32a is connected to at least one lower electrode and is configured to generate a first DC signal. The generated first DC signal is applied to at least one lower electrode. In one embodiment, the second DC generation unit 32b is connected to at least one upper electrode and is configured to generate a second DC signal. The generated second DC signal is applied to at least one upper electrode.

[0035] In various embodiments, the first and second DC signals may also 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 pulse waveform that is rectangular, trapezoidal, triangular, or a combination thereof. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses from a DC signal is connected between the first DC generation unit 32a and at least one lower electrode. Thus, the first DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. In the case where the second DC generation unit 32b and the waveform generation unit constitute a voltage pulse generation unit, the voltage pulse generation unit is connected to at least one upper electrode. The voltage pulses may have a positive polarity or a negative polarity. Additionally, the sequence of voltage pulses may also include one or more positive-polarity voltage pulses and one or more negative-polarity voltage pulses within one cycle. Furthermore, in addition to providing the RF power supply 31, the first and second DC generation units 32a, 32b may be provided, or the first DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0036] The exhaust system 40 can be connected, for example, to a gas discharge port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may also include a pressure regulating valve and a vacuum pump. The pressure inside the plasma processing space 10s can be regulated using the pressure regulating valve. The vacuum pump may include a turbo molecular pump, a dry pump, or a combination thereof.

[0037] Hereinafter, with reference to Figure 2 and Figure 3 a plasma processing apparatus according to an exemplary embodiment will be described. Figure 3 is a diagram showing an upper electrode and a shielding member provided in the Figure 2 illustrated plasma processing apparatus.

[0038] As Figure 3 shown, the side wall 10a of the plasma processing chamber 10 has a substantially cylindrical shape. The side wall 10a is grounded, and its potential is set to the ground potential. The upper end of the side wall 10a is open.

[0039] The plasma processing apparatus 1 has a top 14 above the plasma processing space 10s. The top 14 is provided so as to close the opening of the plasma processing chamber 10. That is, the top 14 covers and closes the opening at the upper end of the side wall 10a. A part of the top 14 is exposed to the plasma processing space 10s.

[0040] The showerhead 13 that forms part of the top 14 includes at least one upper electrode 13d. The upper electrode 13d is part of the top 14 and is configured to be able to apply high-frequency electric power, and is disposed above the substrate support portion 11. The upper electrode 13d is electrically connected to, for example, the first RF generation unit 31a. The first RF generation unit 31a is an example of a high-frequency power source.

[0041] The upper electrode 13d includes a top plate 13e and a first support 13f. The top plate 13e has a substantially disc shape. The top plate 13e is in contact with the plasma processing space 10s. The top plate 13e is formed of a conductive material such as silicon, alumina, or quartz. In addition, the top plate 13e may also be constituted by forming a corrosion-resistant film on the surface of a member made of a conductor such as aluminum. The corrosion-resistant film is formed of a material such as alumina or yttrium oxide, for example.

[0042] The first support 13f is disposed on the top plate 13e. The first support 13f supports the top plate 13e in a detachable manner. The first support 13f is formed of aluminum, for example. The first support 13f provides at least one gas diffusion chamber 13b inside thereof. The first support 13f and the top plate 13e together provide at least one gas inlet 13c. At least one gas inlet 13c extends downward from at least one gas diffusion chamber 13b and penetrates the top plate 13e.

[0043] The top 14 further includes a first insulating member 41. The first insulating member 41 is part of the top 14. The first insulating member 41 is disposed 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 disposed outside the upper electrode 13d (on the side of the side wall 10a). The first insulating member 41 has a substantially annular shape and extends circumferentially so as to surround the upper electrode 13d. The first insulating member 41 is formed of an insulator such as quartz.

[0044] The top 14 further includes a shielding member 42. The shielding member 42 is another part of the top 14 and has conductivity. The shielding member 42 is formed of a silicon-containing material, for example. The shielding member 42 extends from the periphery of the upper electrode 13d to the plasma processing chamber 10. The shielding member 42 extends circumferentially so as to surround the peripheral portion of the top plate 13e. The shielding member 42 has a substantially annular shape, for example. The shielding member 42 is electrically floating. That is, the shielding member 42 has a floating potential different from the potential of the upper electrode 13d and the potential of the plasma processing chamber 10.

[0045] The portion of the top 14 exposed to the plasma processing space 10s is composed of a conductor including the upper electrode 13d and the shielding member 42. For example, the portion of the top 14 exposed to the plasma processing space 10s is composed only of a conductor. Hereinafter, the portion of the top 14 exposed to the plasma processing space 10s will be referred to as the "exposed portion of the top 14". In Figure 3 In the example shown, the exposed portion of the top 14 is composed only of the upper electrode 13d (or the top plate 13e) and the shielding member 42. The shielding member 42 is provided, for example, below the first insulating member 41. The shielding member 42 extends in such a manner that the first insulating member 41 is not exposed to the plasma processing space 10s. In Figure 3 In the example shown, the shielding member 42 is provided below a part of the first support 13f, the first insulating member 41, and a part of the second support 43 described later.

[0046] In the plasma processing apparatus 1, the entire area of the exposed portion of the top 14 is formed of a conductive material. Therefore, reaction products attached to the exposed portion can be removed by the electric bias during dry cleaning. As a result, it is possible to suppress the reaction products from adhering to the substrate W as particles.

[0047] 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 shielding member 42. A minute gap is provided between the second support 43 and the shielding member 42. The second support 43 is provided on the side wall 10a of the plasma processing chamber 10. The second support 43 is electrically connected to the side wall 10a of the plasma processing chamber 10. The potential of the second support 43 is set to the 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 annular shape and extends in the circumferential direction so as to surround the first insulating member 41. The second support 43 is formed of a metal such as aluminum.

[0048] 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 shielding member 42. The at least one second insulating member 44 is located between the plasma processing chamber 10 and the shielding member 42. In Figure 3 In the example shown, the at least one second insulating member 44 is provided in such a manner that its lower surface contacts the upper surface of the outside of the shielding member 42. The at least one second insulating member 44 is provided between the shielding member 42 and the second support 43. The at least one second insulating member 44 is, for example, a member having a substantially annular plate shape. The at least one second insulating member 44 is formed of an insulator such as insulating ceramic, quartz, or metal oxide.

[0049] The plasma processing apparatus 1 further includes at least one third insulating member 45. The at least one third insulating member 45 is disposed below the shielding member 42. The at least one third insulating member 45 is located between the plasma processing chamber 10 and the shielding member 42. The shielding member 42 is supported between the at least one second insulating member 44 and the at least one third insulating member 45.

[0050] In Figure 3 In the example shown, the at least one third insulating member 45 includes a third support body 45a and a sealing member 45b. The third support body 45a is provided on the side wall 10a. The third support body 45a supports the shielding member 42 from below. A part of the inner side of the third support body 45a can be exposed below the top 14 in the plasma processing space 10s. The sealing member 45b is provided between the shielding member 42 and the third support body 45a. The sealing member 45b is arranged in contact with the outer part of the shielding member 42 and the outer part of the third support body 45a. The sealing member 45b is, for example, an O-ring that separates the reduced-pressure environment including the plasma processing space 10s from the atmospheric pressure environment.

[0051] As the path through which the current flows based on the high-frequency electric power supplied to the upper electrode 13d, a first path not passing through the plasma and a second path passing through the plasma are considered. In the first path, the current flows from the upper electrode 13d through the shielding member 42, the at least one second insulating member 44, and the second support body 43 to the side wall 10a. In the second path, the current flows from the upper electrode 13d through the plasma in the plasma processing space 10s to the side wall 10a. The at least one second insulating member 44 reduces the electrostatic capacitance between the shielding member 42 and the second support body 43 and increases the impedance of the first path. The high-frequency electric power supplied to the upper electrode 13d is efficiently coupled through the plasma in the plasma processing space 10s. In addition, the high-frequency electric power supplied to the upper electrode 13d is more efficiently coupled to the plasma also below the shielding member 42.

[0052] Regarding whether the high-frequency electric power is efficiently coupled through the plasma in the plasma processing space 10s in the second path, it can be determined based on the change of the impedance circuit (matcher) provided in the power supply 30. In the case where the high-frequency electric power is more efficiently coupled to the plasma, the resistance value recognized by the impedance circuit increases corresponding to the increase in the plasma density, and the resistance value decreases corresponding to the decrease in the plasma density. The resistance value here refers to the real part of the impedance of the load recognized in the impedance circuit.

[0053] Hereinafter, refer to Figure 4 。 Figure 4It is a graph showing the change in the real part (resistance value) of the impedance of the load of the high-frequency power supply corresponding to the power level of the high-frequency electric power supplied to the upper electrode. In Figure 4 In the shown graph, the horizontal axis is the power level (W) of the high-frequency electric power supplied to the upper electrode 13d, and the vertical axis is the real part of the impedance of the load of the high-frequency power supply (the first RF generation unit 31a), that is, the resistance value (Ω). Figure 4 As the horizontal axis of goes from left to right, the power level (W) of the high-frequency electric power is higher. Figure 4 The characteristics shown in the graph of were obtained in a state where the second insulating member 44 with a thickness of 5 mm was disposed between the shielding member 42 and the second support 43. Among them, the second insulating member 44 is a quartz member. The gap between the upper electrode 13d and the shielding member 42 is 0.5 mm. Figure 4 The shown graph represents the resistance value when the power level of the high-frequency electric power is changed. In addition, the impedance of the load of the high-frequency power supply (the first RF generation unit 31a) and its real part (resistance value) are recognized in the matcher connected between the high-frequency power supply and the upper electrode 31d.

[0054] As Figure 4 shown, the real part of the impedance of the load of the high-frequency power supply, that is, the resistance value, increases as the power level of the high-frequency electric power increases. Furthermore, this resistance value changes linearly with the increase in the power level of the high-frequency electric power. This indicates that the high-frequency electric power is efficiently coupled with the plasma.

[0055] Figure 5 It is a graph showing the relationship between the plasma density and the real part (resistance value) of the impedance of the load of the high-frequency power supply. In Figure 5 In the shown graph, the horizontal axis is the plasma density (S / m), and the vertical axis is the real part of the impedance of the load of the high-frequency power supply, that is, the resistance value (Ω). Figure 5 As the horizontal axis of goes from left to right, the plasma density (S / m) is higher. Figure 5 They respectively represent the measurement results when the thickness of the second insulating member 44 is set to 5 mm, 10 mm, 15 mm, 20 mm, and 35 mm.

[0056] As Figure 5 shown, when generating plasma, the real part of the impedance of the load of the high-frequency power supply, that is, the resistance value, decreases as the plasma density increases. This result indicates that the plasma density can be determined based on this resistance value, and the plasma density can be controlled based on this resistance value. In addition, as Figure 5As shown, the greater the thickness of the second insulating member 44, the more significantly the resistance value changes in correspondence with the change in plasma density. This indicates that by using the second insulating member 44 with a large thickness, it is easy to capture the variation in plasma density and it is possible to control the plasma density more easily.

[0057] As described above, various exemplary embodiments have been described, but are not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and changes can also be made. Additionally, elements in different embodiments can be combined to form other embodiments. For example, at least one of the upper electrode 13d and the shielding member 42 can also be electrically connected to the second DC generation unit 32b. The second DC generation unit 32b is an example of a DC power source.

[0058] Hereinafter, with reference to Figure 6 , a plasma processing apparatus according to another exemplary embodiment employed in a plasma processing apparatus will be described. Figure 6 is a diagram for explaining a plasma processing apparatus according to another exemplary embodiment. Figure 6 The plasma processing apparatus 1A according to the exemplary embodiment shown is different from the plasma processing apparatus 1 in that the first insulating member 41A has a first insulating portion 46 and a second insulating portion 47. That is, the difference is that the plasma processing apparatus 1A does not include the second insulating member 44 of the plasma processing apparatus 1.

[0059] The top 14 includes the first insulating member 41A. The first insulating member 41A is a part of the top 14. The first insulating member 41A is formed of an insulator such as quartz. The first insulating portion 46 of the first insulating member 41A 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 (side wall 10a side) of the upper electrode 13d. The first insulating portion 46 has a substantially annular shape and extends circumferentially so as to surround the upper electrode 13d.

[0060] The second insulating portion 47 is provided on the outer side of the first insulating portion 46 and on the shielding member 42. The second insulating portion 47 has, for example, a substantially annular shape and extends circumferentially so as to surround the first insulating portion 46. The second insulating portion 47 extends so as to protrude outward from the lower end portion of the first insulating portion 46. The second insulating portion 47 is located between the plasma processing chamber 10 and the shielding member 42. In Figure 6 the example shown, the second insulating portion 47 is provided in such a manner that its lower surface contacts the upper surface of the outer side of the shielding member 42. The second insulating portion 47 is provided between the shielding member 42 and the second support 43.

[0061] Thus, in the plasma processing apparatus 1A, the first insulating member 41A having the first insulating portion 46 and the second insulating portion 47 is located between the upper electrode 13d and the plasma processing chamber 10, and between the plasma processing chamber 10 and the shielding member 42. Thereby, the number of components for insulating the current can be reduced, and the man-hours for setting up the plasma processing apparatus 1A can be reduced.

[0062] In addition, a DC connection portion 48 is provided inside the second support 43. The DC connection portion 48 penetrates the second insulating portion 47 from the inside of the second support 43 and is connected to a portion outside the shielding member 42. The portion outside the shielding member 42 is, for example, a portion outside the shielding member 42 in the radial direction, and is a portion not exposed to the plasma processing space 10s. The portion outside the shielding member 42 may also be a peripheral portion of the shielding member 42. The portion outside the shielding member 42 is supported by being sandwiched between the lower end portion of the DC connection portion 48 and at least one third insulating member 45. For example, the lower end portion 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 shielding member 42 in the plasma processing apparatus 1A may not be electrically floating.

[0063] The second DC signal generated by the second DC generation unit 32b is applied to the shielding member 42 via the DC connection portion 48. The second DC generation unit 32b generates a signal having a frequency of, for example, 400 kHz as the second DC signal, and supplies it to the shielding member 42 via the DC connection portion 48. At this time, for example, the first RF generation unit 31a may also generate a signal having a frequency of, for example, 100 MHz as the generation source RF signal, and supply it to the upper electrode 13d. And at this time, the second RF generation unit 31b may also generate a signal having a frequency of, for example, 13 MHz as the bias RF generation signal, and supply it to the lower electrode. Thus, even when the DC connection portion 48 is located outside the first insulating member 41A, by connecting the DC connection portion 48 to the shielding member 42 through the second insulating portion 47, the second DC signal can be appropriately applied to the shielding member 42.

[0064] In addition, the inner wall portion 10t on the inner side of the side wall 10a facing the plasma processing space 10s is formed of silicon. The inner wall portion 10t can serve as a counter electrode facing the shielding member 42. At least a part of the current applied to the shielding member 42 flows through the plasma and the inner wall portion 10t in the plasma processing space 10s to the side wall 10a. Thus, by forming the inner wall portion 10t of silicon, it is not necessary to additionally arrange other components (devices) serving as counter electrodes in the plasma processing space 10s. Therefore, the man-hours for setting up the plasma processing apparatus 1A can be reduced.

[0065] Hereinafter, an example of a processing circuit that can be used as one or more processing circuits in the plasma processing apparatus 1 like the control unit 2 will be described. Figure 7 It is a block diagram of a processing circuit that implements the operations described in this specification on a computer. Figure 7 The processing circuit 130 that can be used to control control processing on an arbitrary computer is illustrated. The descriptions or blocks in the flowchart represent a module, a segment, or a part of code that includes one or more executable commands for implementing the processing, specific logical functions, or steps. As understood by those skilled in the art, other embodiments having functions that can be executed in an order different from the illustrated or described order, such as substantially simultaneously or in the reverse order, are also included within the scope of the exemplary embodiments of the present invention. The various elements, features, and processes described in this specification can be used independently of each other or can be combined in various ways. Any conceivable combination and partial combination can be included within the scope of the present invention.

[0066] In Figure 7 , the processing circuit 130 includes a CPU 1200 that implements one or more of the above-described / hereinafter-described control processes. Processing data and commands can be stored in the memory 1202. These processing data and commands can be stored in a storage medium disk 1204 such as a hard disk drive (HDD), a portable storage medium, or can be stored remotely. In addition, the present invention described in the claims is not limited to the form of a computer-readable medium storing the processing commands of the present invention. For example, these commands can also be stored in a CD, a DVD, a flash memory, a RAM, a ROM, a PROM, an EPROM, an EEPROM, a hard disk, or any other information processing device such as a server and / or a computer with which the processing circuit 130 communicates.

[0067] Furthermore, the present invention described in the claims can be provided as a utility application program, a background daemon, a component of an operating system, or a combination thereof, and can also be executed in conjunction with a CPU 1200 and an operating system known to those skilled in the art, such as Microsoft Windows, UNIX, Solaris, LINUX, Apple MAC-OS.

[0068] The hardware elements that make up the processing circuit 130 can be realized by various circuit elements. And each function of the above-described embodiment can be implemented by a circuit including one or more processing circuits. As Figure 7 shown, the processing circuit includes a processing device having a specific program, for example, a processing device (CPU) 1200. The processing circuit also includes devices such as an application specific integrated circuit (ASIC) and conventional circuit components configured to be able to implement the above-described functions.

[0069] In Figure 7 , the processing circuit 130 includes the CPU 1200 that implements the above processing. The processing circuit 130 can be a general-purpose computer or a specific dedicated machine. In one embodiment, when the processing device 1200 is programmed to control the plasma generation unit 12 and the gas supply unit 20 (especially when implementing Figures 1 to 6 any of the processes described in the

[0070] process), the processing circuit 130 functions as a specific dedicated machine.

[0071] Figure 7 Alternatively, further, as understood by those skilled in the art, the CPU 1200 can also be installed using an FPGA, an ASIC, a PLD, or discrete logic circuits. And the CPU 1200 can also be implemented as multiple processing devices that cooperate in a manner of executing the commands for implementing the processes of the present invention described above in parallel.

[0072] The processing circuit 130 further includes a display device controller 1208 such as a graphics card or a graphics adapter for interfacing with a display device 1210 such as a monitor. The general I / O interface 1212 interfaces with a keyboard and / or a mouse 1214 and a touch panel 1216 integrated with or separate from the display device 1210. The general I / O interface is also connected to various peripheral devices 1218 such as a printer and a scanner.

[0073] The storage device controller 1224 is connected to the storage medium disk 1204 via a communication bus 1226 such as ISA, EISA, VESA, or PCI, and all components of the processing circuit 130 are interconnected. Regarding the general features and functions of the display device 1210, the keyboard and / or the mouse 1214, the display device controller 1208, the storage device controller 1224, the network controller 1206, the sound controller 1220, and the general I / O interface 1212, known features and functions are adopted in this specification for simplicity, and the description is omitted.

[0074] The exemplary circuit elements described in this specification can be replaced with other elements and may have a configuration different from the examples described in this specification. In addition, a circuit configured to implement the features described in this specification can be implemented by multiple circuit units (e.g., chips), or these features can be incorporated into the circuits of a single chipset.

[0075] The functions and features described in this specification can also be executed by various components distributed on the system. For example, one or more processing devices can execute the functions of these systems, and in this case, the processing devices are distributed over multiple components that communicate within the network. As the distributed components, in addition to various human-machine interfaces and communication devices (display monitors, smartphones, tablet computers, personal information terminals (PDA: Personal Digital Assistant), etc.), it can also include one or more client devices and server devices capable of sharing processing. The network can be a private network such as a LAN or WAN, or a public network such as the Internet. Input to the system can be accepted through the direct input of the user or remotely in real-time or as a batch process. Furthermore, a part of the embodiments can be implemented on modules or hardware different from the above. Therefore, other embodiments are also included within the scope of the technical solution.

[0076] Here, various exemplary embodiments included in the present invention are described in [E1] to [E9] below.

[0077] [E1]

[0078] A plasma processing apparatus, comprising:

[0079] A chamber, which is electrically grounded and provides a plasma processing space;

[0080] A substrate support portion, which is disposed in the chamber and configured to be able to support a substrate;

[0081] An upper electrode, which is a part of the top disposed above the plasma processing space to close the opening of the chamber, configured to be able to apply high-frequency electric power, and disposed above the substrate support portion;

[0082] A first insulating member, which is a part of the top and is disposed between the upper electrode and the chamber to electrically separate the upper electrode from the chamber; and

[0083] A shielding member, which is another part of the top, has conductivity, is formed of a silicon-containing material, and extends from the periphery of the upper electrode to the chamber,

[0084] The portion of the top exposed to the plasma processing space is composed of a conductor including the upper electrode and the shielding member.

[0085] [E2]

[0086] The plasma processing apparatus according to [E1], wherein

[0087] It further includes at least one second insulating member, which is disposed outside the first insulating member in a manner located between the chamber and the shielding member, and is disposed on the shielding member.

[0088] [E3]

[0089] The plasma processing apparatus according to [E2], wherein

[0090] It further includes at least one third insulating member, which is disposed under the shielding member in a manner located between the chamber and the shielding member, and supports the shielding member between the at least one second insulating member and the at least one third insulating member.

[0091] [E4]

[0092] The plasma processing apparatus according to [E3], wherein

[0093] The at least one third insulating member is formed of insulating ceramic, quartz or metal oxide.

[0094] [E5]

[0095] The plasma processing apparatus according to [E1], wherein

[0096] The first insulating member has:

[0097] A first insulating portion, which is disposed between the upper electrode and the chamber; and

[0098] A second insulating portion, which is disposed outside the first insulating portion in a manner located between the chamber and the shielding member, and is disposed on the shielding member.

[0099] [E6]

[0100] The plasma processing apparatus according to [E5], wherein

[0101] It further includes at least one other insulating member, which is disposed under the shielding member in a manner located between the chamber and the shielding member, and supports the shielding member between the second insulating portion of the first insulating member and the at least one other insulating member.

[0102] [E7]

[0103] The plasma processing apparatus according to [E6], wherein,

[0104] The at least one other insulating member is formed of insulating ceramic, quartz, or metal oxide.

[0105] [E8]

[0106] The plasma processing apparatus according to any one of [E1] to [E7], wherein,

[0107] It further includes a DC power supply electrically connected to at least one of the upper electrode and the shielding member.

[0108] [E9]

[0109] The plasma processing apparatus according to any one of [E1] to [E7], wherein,

[0110] The shielding member is electrically floating.

[0111] [E10]

[0112] The plasma processing apparatus according to any one of [E1] to [E9], wherein,

[0113] It further includes a high-frequency power supply configured to be able to generate the high-frequency electric power and electrically connected to the upper electrode.

[0114] Based on the above description, it should be understood that various embodiments of the present invention have been described in this specification for illustrative purposes, and various changes can be made without departing from the scope and gist of the present invention. Therefore, the various embodiments described in this specification are not intended to limit the present invention, and the true scope and gist are shown by the technical solution.

[0115] Description of reference numerals

[0116] 1, 1A... Plasma processing apparatus, 2... Control unit, 10... Plasma processing chamber, 10a... Side wall, 10s... Plasma processing space, 11... Substrate support portion, 12... Plasma generation portion, 13... Shower head, 13d... Upper electrode, 13e... Top plate, 13f... First support, 14... Top, 30... Power supply, 31... RF power supply, 31a... First RF generation portion, 32... DC power supply, 32b... Second DC generation portion, 41, 41A... First insulating member, 42... Shielding member, 43... Second support, 44... Second insulating member, 45... Third insulating member, 46... First insulating portion, 47... Second insulating portion, 111... Main body portion, 112... Ring assembly, 1110... Base, 1111... Electrostatic chuck, W... Substrate.

Claims

1. A plasma processing apparatus, characterized in that, Comprising: A chamber, which is electrically grounded and provides a plasma processing space; A substrate support part, which is arranged in the chamber and configured to be able to support a substrate; An upper electrode, which is a part of the top arranged above the plasma processing space to close the opening of the chamber, configured to be able to apply high-frequency electric power, and arranged above the substrate support part; A first insulating member, which is a part of the top and is arranged between the upper electrode and the chamber in a manner of electrically separating the upper electrode from the chamber; And A shielding member, which is another part of the top, has conductivity, is formed of a silicon-containing material, and extends from the periphery of the upper electrode to the chamber, The part of the top exposed to the plasma processing space is composed of a conductor including the upper electrode and the shielding member.

2. The plasma processing apparatus according to claim 1, characterized in that: It further includes at least one second insulating member, which is arranged outside the first insulating member in a manner of being located between the chamber and the shielding member, and is arranged on the shielding member.

3. The plasma processing apparatus according to claim 2, characterized in that: It further includes at least one third insulating member, which is arranged under the shielding member in a manner of being located between the chamber and the shielding member, and supports the shielding member between the at least one second insulating member and the at least one third insulating member.

4. The plasma processing apparatus according to claim 3, characterized in that: The at least one third insulating member is formed of insulating ceramics, quartz or metal oxide.

5. The plasma processing apparatus according to claim 1, characterized in that: The first insulating member has: A first insulating part, which is arranged between the upper electrode and the chamber; and A second insulating part, which is arranged outside the first insulating part in a manner of being located between the chamber and the shielding member, and is arranged on the shielding member.

6. The plasma processing apparatus according to claim 5, characterized in that: It further includes at least one other insulating member, which is arranged under the shielding member in a manner of being located between the chamber and the shielding member, and supports the shielding member between the second insulating part of the first insulating member and the at least one other insulating member.

7. The plasma processing apparatus according to claim 6, characterized in that: The at least one other insulating member is formed of insulating ceramics, quartz or metal oxide.

8. The plasma processing apparatus according to any one of claims 1 to 7, characterized in that: It further includes a DC power supply electrically connected to at least one of the upper electrode and the shielding member.

9. The plasma processing apparatus according to any one of claims 1 to 7, characterized in that: The shielding member is electrically floating.

10. The plasma processing apparatus according to any one of claims 1 to 7, characterized in that: It further includes a high-frequency power supply, which is configured to be able to generate the high-frequency electric power and is electrically connected to the upper electrode.

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