Plasma processing apparatus

Abstract

A plasma processing apparatus disclosed in the present invention has a chamber, a substrate support, a high-frequency power supply, and a bias power supply. The high-frequency power supply generates high-frequency power for generating plasma. The bias power supply is electrically connected to a bias electrode of the substrate support and generates an electric bias. An edge ring mounted on the substrate support receives a part of the electric bias or other electric bias via an impedance adjuster. An outer ring extends radially and outwardly relative to the edge ring and receives a part of the high-frequency power or other high-frequency power.

Description

TECHNICAL FIELD

[0001] An exemplary embodiment of the present application relates to a plasma processing apparatus. BACKGROUND

[0002] A plasma processing apparatus is used for plasma processing of a substrate. The plasma processing apparatus has a chamber, an electrostatic chuck, and a lower electrode. The electrostatic chuck and the lower electrode are provided in the chamber. The electrostatic chuck is provided on the lower electrode. The electrostatic chuck supports a susceptor provided thereon. The susceptor is sometimes referred to as a focus ring. The electrostatic chuck supports a substrate disposed in an area surrounded by the susceptor. In the plasma processing apparatus, when plasma processing is performed, a gas is supplied into the chamber. Also, high-frequency power is supplied to the lower electrode. Plasma is formed from the gas in the chamber. The substrate is processed by chemical species such as ions, radicals, and the like from the plasma.

[0003] If plasma processing is performed, the susceptor is consumed, and the thickness of the susceptor becomes small. If the thickness of the susceptor becomes small, the position of the upper end of a plasma sheath layer (hereinafter, referred to as "sheath layer") above the susceptor becomes low. The position of the upper end of the sheath layer above the susceptor in the vertical direction should be equal to the position of the upper end of the sheath layer above the substrate in the vertical direction. A plasma processing apparatus capable of adjusting the position of the upper end of the sheath layer above the susceptor in the vertical direction is disclosed in Japanese Patent Application Publication No. 2008-227063 (hereinafter, referred to as "Patent Document 1"). The plasma processing apparatus described in Patent Document 1 is configured to apply a direct-current voltage to the susceptor. Also, the plasma processing apparatus described in Patent Document 1 is configured to adjust the power level of the high-frequency power supplied to the lower electrode when the direct-current voltage is applied to the susceptor. SUMMARY

[0004] The present application provides a technique capable of adjusting the thickness of the sheath layer on the susceptor and the density distribution of the plasma in the radial direction.

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, a high-frequency power supply, and a bias power supply. The substrate support has a bias electrode. The high-frequency power supply generates high-frequency power supplied to the high-frequency electrode to generate plasma above a substrate supported by the substrate support within the chamber. The bias power supply is connected to the bias electrode via an electrical path. An edge ring is mounted on the substrate support. The edge ring is electrically connected to the bias power supply, or to other bias power supplies, via an impedance regulator that provides variable impedance between the bias electrode and the edge ring, or between the electrical path and the edge ring. An outer ring extends radially and outward relative to the edge ring. The outer ring is electrically connected to the high-frequency power supply in a manner that receives a portion of the high-frequency power, or to other high-frequency power supplies in a manner that receives other high-frequency power.

[0006] According to an exemplary embodiment, the thickness of the sheath on the edge ring can be adjusted and the density distribution of the plasma in the radial direction can be adjusted. Attached Figure Description

[0007] Figure 1 This is a schematic diagram illustrating a plasma processing apparatus according to an exemplary embodiment.

[0008] Figure 2 This is a diagram that schematically illustrates a plasma processing apparatus according to another exemplary embodiment.

[0009] Figure 3 This is a schematic diagram illustrating a plasma processing apparatus according to yet another exemplary embodiment.

[0010] Figure 4 This is a schematic diagram illustrating a plasma processing apparatus according to yet another exemplary embodiment. Detailed Implementation

[0011] The following describes various exemplary embodiments.

[0012] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, a high-frequency power supply, and a bias power supply. The substrate support has a bias electrode. The high-frequency power supply generates high-frequency power supplied to the high-frequency electrode to generate plasma above a substrate supported by the substrate support within the chamber. The bias power supply is connected to the bias electrode via an electrical path. An edge ring is mounted on the substrate support. The edge ring is electrically connected to the bias power supply, or to other bias power supplies, via an impedance regulator that provides variable impedance between the bias electrode and the edge ring, or between the electrical path and the edge ring. An outer ring extends radially and outward relative to the edge ring. The outer ring is electrically connected to the high-frequency power supply in a manner that receives a portion of the high-frequency power, or to other high-frequency power supplies in a manner that receives other high-frequency power.

[0013] According to the above embodiment, the level of negative bias in the edge ring is adjusted by an impedance regulator or other bias power supply. Therefore, according to the above embodiment, the thickness of the sheath layer on the edge ring can be adjusted. Furthermore, in the above embodiment, a portion of the high-frequency power or other high-frequency power is supplied to the outer ring. Therefore, according to the above embodiment, the plasma density can be adjusted even above the outer ring. Therefore, according to the above embodiment, the radial plasma density distribution can be adjusted in the space including the region outside the region on the edge ring.

[0014] In one exemplary embodiment, the plasma processing apparatus may further include a first electrode and a second electrode. The first electrode is electrically coupled to an edge ring. The first electrode may also be capacitively coupled to the edge ring. The second electrode is electrically coupled to an outer ring. The second electrode may also be capacitively coupled to the outer ring. An impedance regulator provides variable impedance between the bias electrode and the first electrode, or between the electrical path and the first electrode. The outer ring receives a portion of the high-frequency power or additional high-frequency power from another high-frequency power source via the second electrode.

[0015] In one exemplary embodiment, the substrate support may have a base and an electrostatic chuck disposed on the base.

[0016] In one exemplary embodiment, the base plate may provide a lower electrode as a bias electrode. The lower electrode may be the high-frequency electrode described above. In this embodiment, a high-frequency power supply may be electrically connected to the lower electrode via the aforementioned electrical path.

[0017] In one exemplary embodiment, the plasma processing apparatus may further include an impedance regulator. This impedance regulator provides variable impedance between the aforementioned electrical path and the outer ring, or between the lower electrode and the outer ring.

[0018] In one exemplary embodiment, the plasma processing apparatus may further include a filter connected between the impedance regulator and the second electrode, the impedance regulator providing variable impedance between the electrical path and the outer ring or between the lower electrode and the outer ring. The filter may have frequency characteristics that selectively pass high-frequency power through an electrical bias supplied from a bias power supply to the lower electrode.

[0019] In one exemplary embodiment, a bias electrode may be disposed in an electrostatic chuck. A base may be provided as a lower electrode serving as a high-frequency electrode. A high-frequency power supply may be electrically connected to the lower electrode.

[0020] In one exemplary embodiment, the plasma processing apparatus may also include an impedance regulator. The impedance regulator provides variable impedance between the electrical path connecting the high-frequency power supply to the lower electrode and the outer ring, or between the lower electrode and the outer ring.

[0021] In one exemplary embodiment, the outer ring may extend in a manner that surrounds the edge ring.

[0022] In one exemplary embodiment, the bias power supply may be configured to supply high-frequency bias power to the bias electrode, or to periodically apply a pulsed voltage or a voltage with arbitrary waveform to the bias electrode. The pulsed voltage may have a negative polarity. The pulsed voltage may be a pulsed, negative-polarity DC voltage.

[0023] Hereinafter, various exemplary embodiments will be described in detail with reference to the accompanying drawings. Furthermore, in the drawings, the same or equivalent parts are labeled with the same symbols.

[0024] Figure 1 This is a schematic diagram illustrating a plasma processing apparatus according to an exemplary embodiment. Figure 1 The plasma processing apparatus 1 shown is a capacitively coupled plasma processing apparatus. The plasma processing apparatus 1 includes a chamber 10. An internal space 10s is provided within the chamber 10. The central axis of the internal space 10s is an axis AX extending in the vertical direction.

[0025] In one embodiment, the chamber 10 may include a chamber body 12. The chamber body 12 has a generally cylindrical shape. An internal space 10s is disposed within the chamber body 12. The chamber body 12 is made of, for example, aluminum. The chamber body 12 is electrically grounded. A plasma-resistant membrane is formed on the inner wall surface of the chamber body 12, i.e., the wall surface dividing the internal space 10s. This membrane may be a ceramic membrane formed by anodizing or by forming a yttrium oxide membrane.

[0026] The sidewall of the chamber body 12 is provided with a passage 12p. When the substrate W is transported between the internal space 10s and the outside of the chamber 10, the substrate W passes through the passage 12p. A gate valve 12g is provided along the sidewall of the chamber body 12 for opening and closing the passage 12p.

[0027] The plasma processing apparatus 1 also includes a substrate support 16. The substrate support 16 is configured to support a substrate W placed on the substrate support 16 within the chamber 10. The substrate W has a generally disk-shaped form. The substrate W is placed on the substrate support 16 with its center aligned with axis AX. The substrate support 16 is configured to further support an edge ring ER. The edge ring ER has a ring shape. The edge ring ER may be conductive. The edge ring ER is formed, for example, of silicon or silicon carbide. The edge ring ER is mounted on the substrate support 16 with its central axis aligned with axis AX. The substrate W is disposed on the substrate support 16 within the area surrounded by the edge ring ER.

[0028] The substrate support 16 may be surrounded by an insulating portion 17. The insulating portion 17 extends radially relative to the axis AX and circumferentially outside the substrate support 16. The insulating portion 17 is formed of an insulating material such as quartz. The insulating portion 17 can support the substrate support 16.

[0029] The substrate support 16 has a base 18. The substrate support 16 may also have an electrostatic chuck 20. The base 18 and the electrostatic chuck 20 may be disposed in the chamber 10. The lower electrode 18 is formed of a conductive material such as aluminum and has a generally disk-shaped form. The central axis of the base 18 is axis AX.

[0030] A flow path 18f is provided in the lower electrode 18. Flow path 18f is for heat exchange medium. The heat exchange medium is, for example, a refrigerant. Flow path 18f is connected to a heat exchange medium supply device 22. The supply device 22 is located outside the chamber 10. Flow path 18f receives the heat exchange medium supplied from the supply device 22. The heat exchange medium supplied to flow path 18f returns to the supply device 22.

[0031] An electrostatic chuck 20 is disposed on the base 18. When the substrate W is processed in the internal space for 10 seconds, the substrate W is placed on the electrostatic chuck 20 and held by the electrostatic chuck 20.

[0032] The electrostatic chuck 20 has a body and chuck electrodes. The body of the electrostatic chuck 20 is formed of a dielectric such as aluminum oxide or aluminum nitride. The body of the electrostatic chuck 20 has a generally disc-shaped form. The central axis of the electrostatic chuck 20 is axis AX. The chuck electrodes are disposed within the body of the electrostatic chuck 20. The chuck electrodes have a film shape. The chuck electrodes are electrically connected to a DC power supply via a switch. When a voltage from the DC power supply is applied to the chuck electrodes, an electrostatic attraction is generated between the electrostatic chuck 20 and the substrate W. Through the generated electrostatic attraction, the substrate W is attracted to the electrostatic chuck 20 and held by the electrostatic chuck 20.

[0033] The electrostatic chuck 20 includes a substrate placement area. The substrate placement area is a region having a generally disk-shaped structure. The central axis of the substrate placement area is axis AX. When processing the substrate W within the chamber 10, the substrate W is placed on the upper surface of the substrate placement area.

[0034] In one embodiment, the electrostatic chuck 20 may further include an edge ring mounting region. The edge ring mounting region extends circumferentially such that it surrounds the substrate mounting region around the central axis of the electrostatic chuck 20. An edge ring ER is mounted on the upper surface of the edge ring mounting region. The edge ring ER may be partially mounted on the insulating portion 17.

[0035] The plasma processing apparatus 1 may also provide a gas supply line 24. The gas supply line 24 supplies heat transfer gas, such as He gas, from the gas supply mechanism to the gap between the upper surface of the electrostatic chuck 20 and the back (lower surface) of the substrate W.

[0036] The plasma processing apparatus 1 also includes an upper electrode 30. The upper electrode 30 is disposed above the substrate support 16. The upper electrode 30, together with the component 32, seals the upper opening of the chamber body 12. The component 32 is insulating. The upper electrode 30 is supported on the upper part of the chamber body 12 via the component 32.

[0037] The upper electrode 30 may include a top plate 34 and a support 36. The lower surface of the top plate 34 divides an internal space 10s. The top plate 34 provides a plurality of vent holes 34a. The plurality of vent holes 34a penetrate the top plate 34 along its thickness direction (vertical direction). The top plate 34 is formed of silicon, for example. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is formed on the surface of an aluminum component. This film may be a ceramic film formed by anodizing or formed of yttrium oxide.

[0038] The support body 36 detachably supports the top plate 34. The support body 36 is formed of a conductive material, for example, aluminum. A gas diffusion chamber 36a is provided within the support body 36. The support body 36 also provides a plurality of gas holes 36b. The plurality of gas holes 36b extend downward from the gas diffusion chamber 36a and communicate with a plurality of exhaust holes 34a respectively. The support body 36 also provides a gas inlet port 36c. The gas inlet port 36c is connected to the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas inlet port 36c.

[0039] A gas source group 40 is connected to the gas supply pipe 38 via a valve group 41, a flow controller group 42, and a valve group 43. The gas supply unit comprises the gas source group 40, valve group 41, flow controller group 42, and valve group 43. The gas source group 40 includes multiple gas sources. Valve groups 41 and 43 each include multiple valves (e.g., open and close valves). The flow controller group 42 includes multiple flow controllers. These multiple flow controllers are either mass flow controllers or pressure-controlled flow controllers. The multiple gas sources of the gas source group 40 are connected to the gas supply pipe 38 via valves corresponding to valve group 41, flow controllers corresponding to flow controller group 42, and valves corresponding to valve group 43. The plasma processing apparatus 1 can supply gas from one or more selected gas sources from the multiple gas sources of the gas source group 40 to the internal space for 10 seconds at individually adjustable flow rates.

[0040] The plasma processing apparatus 1 may also include a baffle member 48. The baffle member 48 extends between the insulating portion 17 and the sidewall of the chamber body 12. The baffle member 48 may be constructed, for example, by coating an aluminum component with a ceramic such as yttrium oxide. The baffle member 48 is provided with a plurality of through holes. The space above the baffle member 48 and the space below the baffle member 48 are connected via the plurality of through holes.

[0041] The plasma processing apparatus 1 may also include an exhaust device 50. The exhaust device 50 is located below the baffle member 48 and is connected to the bottom of the chamber body 12 via an exhaust pipe 52. The exhaust device 50 has a pressure controller such as an automatic pressure control valve and a vacuum pump such as a turbomolecular pump, which can reduce the pressure in the internal space by 10s.

[0042] The plasma processing apparatus 1 also includes a high-frequency power supply 61. The high-frequency power supply 61 generates high-frequency power HF supplied to a high-frequency electrode in order to generate plasma above the substrate W supported by the substrate support 16. The high-frequency power HF has a frequency in the range of 27 to 100 MHz, for example, 40 MHz or 60 MHz. In one embodiment, the high-frequency electrode is a base 18. That is, in one embodiment, the base 18 is provided with a lower electrode serving as the high-frequency electrode. The high-frequency power supply 61 is connected to the base 18 via an integrator 63. The integrator 63 has an integration circuit configured to integrate the impedance of the load side (base 18 side) of the high-frequency power supply 61 with the output impedance of the high-frequency power supply 61. In one embodiment, the high-frequency power supply 61 may be connected to the base 18 via the integrator 63 and an electrical path 71. In one embodiment, the electrical path 71 connects a bias power supply 62 to the base 18. That is, in one embodiment, the base 18 is provided with a lower electrode serving as a bias electrode.

[0043] The bias power supply 62 is configured as a bias electrode for the substrate support 16. Figure 1 In the example, an electrical bias BE is applied to the substrate 18. The electrical bias BE can be used to introduce ions into the substrate W.

[0044] In one embodiment, the bias power supply 62, acting as an electrical bias BE, can generate high-frequency bias power. The frequency of this high-frequency bias power differs from the frequency of the high-frequency power HF. The frequency of the high-frequency bias power can be lower than the frequency of the high-frequency power HF. The frequency of the high-frequency bias power is within the range of 50 kHz to 27 MHz, for example, 400 kHz. Furthermore, when the high-frequency power supply 61 is connected to the upper electrode 30 instead of the base 18, the frequency of the high-frequency bias power generated by the bias power supply 62 can be lower than, higher than, or the same as the frequency of the high-frequency power HF.

[0045] In order to supply high-frequency bias power to the bias electrode, the bias power supply 62 connects to the bias electrode via the integrator 64. Figure 1 In the example, base station 18) is connected. Integrator 64 has an integration circuit configured to integrate the impedance on the load side of bias power supply 62 with the output impedance of bias power supply 62.

[0046] In addition, high-frequency bias power can be continuously supplied to base station 18. Alternatively, high-frequency bias power can be intermittently and periodically supplied to base station 18.

[0047] In another embodiment, the bias power supply 62 may be configured to apply a pulsed voltage or a voltage with an arbitrary waveform to the bias electrode as an electrical bias BE. Figure 1(In the example, base 18). The pulsed voltage can be negative. The pulsed voltage can be a pulsed negative DC voltage. The pulsed voltage can be applied periodically to base 18. The level of the pulsed voltage can change during the period during which the pulsed voltage is applied to the bias electrode.

[0048] In one embodiment, the plasma processing apparatus 1 may further include a first electrode 81. The first electrode 81 is electrically coupled to the edge ring ER. The first electrode 81 may also be capacitively coupled to the edge ring ER. The first electrode 81 is disposed below the edge ring ER. In one embodiment, the first electrode 81 may be disposed within the edge ring mounting region of the electrostatic chuck 20. In another embodiment, the first electrode 81 may be disposed in the insulating portion 17. Alternatively, the first electrode 81 may be directly coupled to the edge ring ER. The first electrode 81 may be a single electrode or may extend circumferentially around the axis AX. Alternatively, the first electrode 81 may also include a plurality of electrodes arranged circumferentially around the axis AX. The plurality of electrodes constituting the first electrode 81 may be arranged at equal intervals.

[0049] In one embodiment, the plasma processing apparatus 1 may further include an impedance regulator 83. The impedance regulator 83 provides a variable impedance. The variable impedance of the impedance regulator 83 can be controlled by the control unit MC, described later. The impedance regulator 83 is connected between the high-frequency electrode and the edge ring ER. In one embodiment, the impedance regulator 83 is connected to the high-frequency electrode (… Figure 1 In the example, this is between the base 18 and the first electrode 81. In one embodiment, the impedance regulator 83 includes one or more variable impedance elements. The one or more variable impedance elements may include variable capacitance capacitors. In another embodiment, the impedance regulator 83 may include a circuit formed by parallel connection of multiple series circuits. The multiple series circuits may each include a series connection of a fixed impedance element and a switching element. The fixed impedance element is, for example, a fixed capacitance capacitor.

[0050] In one embodiment, the plasma processing apparatus 1 may further include a second electrode 82. The second electrode 82 is electrically coupled to the outer ring OR. The second electrode 82 may also be capacitively coupled to the outer ring OR. The outer ring OR has a ring shape. The outer ring OR may be conductive. The outer ring OR is formed, for example, of silicon or silicon carbide. The outer ring OR extends radially and outward relative to the edge ring ER. The outer ring OR is arranged such that its axis AX aligns with its central axis. In one embodiment, the outer ring OR extends to surround the edge ring ER. The outer ring OR may be mounted on a substrate support 16 or an insulating portion 17.

[0051] like Figure 1As shown, the second electrode 82 can be disposed below the outer ring OR. The second electrode 82 can be disposed in or on the surface of the insulating portion 17. Alternatively, the second electrode 82 can be directly coupled to the outer ring OR. The second electrode 82 can be a single electrode or extend circumferentially around the axis AX. Alternatively, the second electrode 82 can also include multiple electrodes arranged circumferentially around the axis AX. The multiple electrodes constituting the second electrode 82 can be arranged at equal intervals.

[0052] In plasma processing apparatus 1, a portion of high-frequency power HF is supplied to the outer ring OR. In one embodiment, a portion of the high-frequency power HF is supplied to the outer ring OR via a second electrode 82. The outer ring OR is connected to the electrical path 71 via an impedance regulator 84. In one embodiment, the second electrode 82 is connected to the electrical path 71 via the impedance regulator 84. That is, the impedance regulator 84 is connected between the electrical path 71 and the second electrode 82. The impedance regulator 84 provides a variable impedance. The variable impedance of the impedance regulator 84 can be controlled by a control unit MC. In one embodiment, the impedance regulator 84 includes one or more variable impedance elements. The one or more impedance elements may include variable capacitance capacitors. In another embodiment, the impedance regulator 84 may include a circuit formed by parallel connection of multiple series circuits. The multiple series circuits may each include a series connection of a fixed impedance element and a switching element. The fixed impedance element is, for example, a fixed capacitance capacitor.

[0053] In one embodiment, the plasma processing apparatus 1 may further include a control unit MC. The control unit MC is a computer equipped with a processor, storage device, input device, display device, etc., and controls each part of the plasma processing apparatus 1. Specifically, the control unit MC executes a control program stored in the storage device and controls each part of the plasma processing apparatus 1 based on process data stored in the storage device. Through the control of the control unit MC, the program specified by the process data is executed in the plasma processing apparatus 1.

[0054] The control unit MC can be configured to control the impedance regulator 83 and the impedance regulator 84, and set the impedance of the impedance regulator 83 and the impedance of the impedance regulator 84.

[0055] The plasma processing apparatus 1 may also include one or more sensors. These sensors may include sensors for measuring the plasma density distribution within the internal space 10s. They may also include sensors for measuring the voltages of the substrate W, the edge ring ER, and the outer ring OR. Furthermore, they may include sensors for measuring the currents flowing to the substrate W, the edge ring ER, and the outer ring OR, respectively. Finally, they may include sensors for measuring the luminous intensity distribution within the internal space 10s. The control unit MC can control the impedance regulators 83 and 84 and set their impedances based on one or more measured values ​​obtained from the sensors.

[0056] Alternatively, the control unit MC can use pre-set data based on the tendency of the program executed according to the process data to control the impedance regulators 83 and 84 and set their impedances. Alternatively, the control unit MC can use data corresponding to the execution time length of the program executed according to the process data to control the impedance regulators 83 and 84 and set their impedances. Alternatively, the control unit MC can use data corresponding to the consumption prediction of the edge ring ER and outer ring OR to control the impedance regulators 83 and 84 and set their impedances.

[0057] When plasma processing is performed in plasma processing apparatus 1, gas is supplied to the internal space for 10 seconds. Then, by supplying high-frequency power HF and / or electrical bias BE, the gas is excited in the internal space for 10 seconds. As a result, plasma is generated in the internal space for 10 seconds. The substrate W is processed by chemical species such as ions and free radicals from the generated plasma. For example, the substrate is etched by chemical species from the plasma.

[0058] In the plasma processing device 1, the bias electrode is adjusted by the impedance regulator 83. Figure 1 In this example, the distribution ratio of the electrical bias BE between the base 18 and the edge ring ER is used. Therefore, the level of the negative bias in the edge ring ER is adjusted by the impedance regulator 83. Thus, according to the plasma processing apparatus 1, the thickness of the sheath on the edge ring ER can be adjusted.

[0059] Furthermore, in the plasma processing apparatus 1, a portion of the high-frequency power HF is supplied to the outer ring OR. The high-frequency electrode ( ) is adjusted by the impedance regulator 84. Figure 1 In the example, this refers to the distribution ratio of high-frequency power (HF) between the base station 18 and the outer ring OR. Therefore, according to the plasma processing device 1, the plasma density can be adjusted even above the outer ring OR. Therefore, according to the plasma processing device 1, the radial plasma density distribution can be adjusted in the space including the region outside the region on the edge ring ER.

[0060] In one embodiment, the electrical path 71 can be configured to uniformly distribute power to the base station 18 circumferentially relative to the axis AX. In another embodiment, the electrical path 71 may include multiple branch lines respectively connected to multiple locations on the base station 18. The multiple locations are equidistant from the axis AX and are arranged at equal intervals circumferentially relative to the axis AX. Furthermore, the multiple branch lines of the electrical path 71 are arranged at equal intervals circumferentially relative to the axis AX. Additionally, the electrical lengths of the electrical path 71 relative to each of the multiple locations on the base station 18 are approximately equal. According to this embodiment, the base station 18 can be uniformly powered via the electrical path 71.

[0061] In one embodiment, the plasma processing apparatus 1 may further include an electrical path 72. The electrical path 72 is used for biasing electrodes (in...) Figure 1 In this example, the electrical path 72 is an electrical path that distributes and supplies power to the edge ring ER (or the first electrode 81) between the base 18 and the edge ring ER. The electrical path 72 may include multiple branch lines connected to multiple locations on the edge ring ER (or the first electrode 81). These multiple locations are equidistant from the axis AX and are arranged at equal intervals circumferentially relative to the axis AX. Furthermore, the multiple branch lines of the electrical path 72 are arranged at equal intervals circumferentially relative to the axis AX. Also, the electrical lengths of the electrical path 72 relative to each of the multiple locations on the edge ring ER (or the first electrode 81) are approximately equal. According to this embodiment, the edge ring ER can be uniformly powered via the electrical path 72.

[0062] In one embodiment, the plasma processing apparatus 1 may further include an electrical path 73. The electrical path 73 is used for high-frequency electrodes ( Figure 1 In this example, the electrical path 73 distributes and supplies power to the outer ring OR (or the second electrode 82) between the base 18 and the outer ring OR. The electrical path 73 may include multiple branch lines connected to multiple locations on the outer ring OR (or the second electrode 82). These multiple locations are equidistant from the axis AX and are arranged at equal intervals circumferentially relative to the axis AX. Furthermore, the multiple branch lines of the electrical path 73 are arranged at equal intervals circumferentially relative to the axis AX. The electrical lengths of the electrical path 73 relative to the multiple locations on the outer ring OR (or the second electrode 82) are approximately equal to each other. According to this embodiment, power can be uniformly supplied to the outer ring OR via the electrical path 73.

[0063] In one embodiment, the plasma processing apparatus 1 may further include a filter 74. The filter 74 is connected between the impedance regulator 84 and the outer ring OR (or the second electrode 82). The filter 74 may have frequency characteristics that selectively allow high-frequency power HF to pass through the electrical bias BE. Alternatively, the filter 74 may have frequency characteristics that selectively allow the electrical bias BE to pass through the high-frequency power HF. Alternatively, the passband of the filter 74 may be changed to the passband of the high-frequency power HF, the passband of the electrical bias BE, or any one of both.

[0064] The following is for reference. Figure 2 . Figure 2 This is a schematic diagram illustrating a plasma processing apparatus according to another exemplary embodiment. The following describes... Figure 2 The differences between plasma processing apparatus 1B and plasma processing apparatus 1 will be explained.

[0065] The plasma processing apparatus 1B does not include an impedance regulator 84. The plasma processing apparatus 1B also includes a high-frequency power supply 91. The high-frequency power supply 91 is configured to generate high-frequency power supplied to the outer ring OR. The frequency of the high-frequency power generated by the high-frequency power supply 91 may be the same as or different from the frequency of the high-frequency power HF.

[0066] The high-frequency power supply 91 is connected to the outer ring OR via integrator 93 and electrical path 75. The high-frequency power supply 91 can be connected to the second electrode 82 via integrator 93 and electrical path 75. Integrator 93 has an integration circuit configured to integrate the impedance on the load side of the high-frequency power supply 91 with the output impedance of the high-frequency power supply 91.

[0067] In one embodiment, the electrical path 75 may include multiple branch lines connected to multiple locations on the outer ring OR (or the second electrode 82). The multiple locations are equidistant from the axis AX and are arranged at equal intervals circumferentially relative to the axis AX. Furthermore, the multiple branch lines of the electrical path 75 are arranged at equal intervals circumferentially relative to the axis AX. Also, the electrical lengths of the electrical path 75 relative to the multiple locations on the outer ring OR (or the second electrode 82) are approximately equal to each other. According to this embodiment, the outer ring OR can be uniformly powered via the electrical path 75.

[0068] In the plasma processing apparatus 1B, the control unit MC can further control the high-frequency power supply 91 and set the level of the high-frequency power generated by the high-frequency power supply 91 based on one or more measurement values ​​obtained by measuring the plasma processing apparatus 1 through one or more sensors as described above.

[0069] Alternatively, the control unit MC can use data preset according to the tendency of the program executed according to the process data to further control the high-frequency power supply 91 and set the level of the high-frequency power generated by the high-frequency power supply 91. Alternatively, the control unit MC can use data corresponding to the execution time length of the program executed according to the process data to further control the high-frequency power supply 91 and set the level of the high-frequency power generated by the high-frequency power supply 91. Alternatively, the control unit MC can use data corresponding to the consumption prediction of the edge ring ER and the outer ring OR to further control the high-frequency power supply 91 and set the level of the high-frequency power generated by the high-frequency power supply 91.

[0070] The following is for reference. Figure 3 . Figure 3 This is a schematic diagram illustrating a plasma processing apparatus according to yet another exemplary embodiment. The following describes... Figure 3 The differences between plasma processing apparatus 1C and plasma processing apparatus 1B shown will be explained.

[0071] The plasma processing apparatus 1C does not include an impedance regulator 83. In the plasma processing apparatus 1C, a bias power supply 92 is connected to the edge ring ER (or the first electrode 81) via an integrator 94 and an electrical path 72. The bias power supply 92 is the same power supply as the bias power supply 62. The integrator 94 includes an integration circuit for integrating the impedance on the load side of the bias power supply 92 with the output impedance of the bias power supply 92.

[0072] In the plasma processing apparatus 1C, the control unit MC can further control the bias power supply 92 and set the level of the electrical bias generated by the bias power supply 92 based on one or more measurement values ​​obtained by the plasma processing apparatus 1 through one or more sensors as described above.

[0073] Alternatively, the control unit MC can use pre-set data based on the tendency of the program executed according to the process data to further control the bias power supply 92 and set the electrical bias level generated by the bias power supply 92. Alternatively, the control unit MC can use data corresponding to the execution time length of the program executed according to the process data to further control the bias power supply 92 and set the electrical bias level generated by the bias power supply 92. Alternatively, the control unit MC can use data corresponding to the consumption prediction of the edge ring ER and the outer ring OR to further control the bias power supply 92 and set the electrical bias level generated by the bias power supply 92.

[0074] In addition, in the plasma processing apparatus 1C, other high-frequency power sources that generate high-frequency power can be electrically connected to the edge ring ER (or the first electrode 81) via an integrator.

[0075] The following is for reference. Figure 4 . Figure 4This is a schematic diagram illustrating a plasma processing apparatus according to yet another exemplary embodiment. The following describes... Figure 4 The differences between the plasma processing apparatus 1D and the plasma processing apparatus 1C will be explained. In the plasma processing apparatus 1D, a bias electrode 21 is disposed in the electrostatic chuck 20. The bias electrode 21 may also serve as a chuck electrode, or it may be a different electrode from the chuck electrode. In the plasma processing apparatus 1D, the bias power supply 62 is connected to the bias electrode 21 via an electrical path different from the electrical path 71.

[0076] The above descriptions have illustrated various exemplary embodiments, but the embodiments are not limited to these exemplary embodiments. Various additions, omissions, substitutions, and modifications can be made. Furthermore, elements from different embodiments can be combined to form other embodiments.

[0077] For example, in another embodiment, the high-frequency power supply 61 may be connected to the upper electrode 30 via the integrator 63 instead of to the base plate 18. In this case, the upper electrode 30 is used as a high-frequency electrode.

[0078] In another embodiment, when the high-frequency power supply 61 is connected to the base station 18 via the electrical path 71, the impedance regulator 83 can be connected between the electrical path 71 and the edge ring ER (or the first electrode 81).

[0079] In another embodiment, the outer ring OR can be positioned vertically above the edge ring ER. In yet another embodiment, the outer ring OR can be configured to surround the upper electrode 30. In this case, the outer ring OR can be configured within the component 32.

[0080] In another embodiment, the impedance regulator 84 may be connected between the base 18 and the outer ring OR (or the second electrode 82).

[0081] In another embodiment, an additional bias power source may be connected to the outer ring OR (or the second electrode 82) via electrical path 75. The additional bias power source may generate high-frequency bias power supplied to the outer ring OR, or it may periodically generate pulsed voltages or voltages with arbitrary waveforms applied to the outer ring OR.

[0082] As can be understood from the above description, various embodiments of the present invention have been described in this specification for illustrative purposes, and various modifications can be made without departing from the scope and spirit of the invention. Therefore, the invention is not limited to the various embodiments disclosed in this specification, and the true scope and spirit are indicated by the appended claims.

Claims

1. A plasma processing apparatus comprising: a chamber; a substrate support having a bias electrode; a high frequency power source generating high frequency power supplied to a high frequency electrode for generating plasma above a substrate supported by the substrate support in the chamber; and a bias power source connected to the bias electrode via an electric path, an edge ring mounted on the substrate support is electrically connected to the bias power source via an impedance adjuster providing variable impedance between the bias electrode and the edge ring or between the electric path and the edge ring, or is electrically connected to another bias power source, an outer ring extending radially and outwardly with respect to the edge ring is electrically connected to the high frequency power source to receive a part of the high frequency power or is electrically connected to another high frequency power source to receive another high frequency power, the substrate support has a base and an electrostatic chuck provided on the base, the bias electrode is provided in the electrostatic chuck, the base provides a lower electrode as the high frequency electrode, the high frequency power source is electrically connected to the lower electrode.

2. The plasma processing apparatus according to claim 1, further comprising: a first electrode electrically coupled to the edge ring; and a second electrode electrically coupled to the outer ring, the impedance adjuster provides variable impedance between the bias electrode and the first electrode or between the electric path and the first electrode, the outer ring receives a part of the high frequency power or another high frequency power from another high frequency power source via the second electrode.

3. The plasma processing apparatus according to claim 2, further comprising an insulating portion surrounding the substrate support, the edge ring is disposed on the electrostatic chuck, the outer ring is placed on the insulating portion, the first electrode is disposed in an edge ring placement area of the electrostatic chuck, the second electrode is disposed in the insulating portion.

4. The plasma processing apparatus according to any one of claims 1 to 3, further comprising: an impedance adjuster providing variable impedance between an electric path connecting the high frequency power source to the lower electrode and the outer ring or between the lower electrode and the outer ring.

5. The plasma processing apparatus according to any one of claims 1 to 3, wherein, the outer ring extends in a manner surrounding the edge ring.

6. The plasma processing apparatus according to any one of claims 1 to 3, wherein, the bias power source is configured to supply high frequency bias power to the bias electrode, or to periodically apply a voltage in a pulse shape or a voltage having an arbitrary waveform to the bias electrode. ​ ​ ​ ​ ​ ​ ​

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