Plasma processing apparatus and etching method

Abstract

To appropriately control the incident angle of ions in plasma to an edge region of a substrate in plasma processing.SOLUTION: A plasma processing device comprises: a substrate support including a lower electrode, a substrate supporting surface for supporting a substrate and an edge ring disposed to enclose the substrate; an upper electrode disposed above the lower electrode; a power source unit including a source power supply configured to supply source power to the upper electrode or the lower electrode and at least one bias power supply configured to supply one or two or more levels of bias power different in frequency to the lower electrode; at least one variable passive element electrically connected to the edge ring; and at least one bypass circuit configured to electrically connect the power source unit with the edge ring and supply a part of at least one level of power selected from the group consisting of the source power and at least one level of bias power to the edge ring.SELECTED DRAWING: Figure 2A

Description

【Technical Field】 【0001】 The present disclosure relates to a plasma processing apparatus and an etching method. 【Background Art】 【0002】 Patent Document 1 discloses a system for controlling the directionality of an ion beam in an edge region within a plasma chamber. This system includes an RF generator configured to generate an RF signal, an impedance matching circuit that receives the RF signal and generates a modified RF signal, and a plasma chamber. The plasma chamber includes an edge ring and a coupling ring that receives the modified RF signal. The coupling ring includes an electrode that receives the modified RF signal and an electrode that generates a capacitance between the electrode and the edge ring to control the directionality of the ion beam. 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2017-228526 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 The technology according to the present disclosure appropriately controls the incident angle of ions in the plasma with respect to the edge region of the substrate in plasma processing. 【Means for Solving the Problems】 【0005】 A plasma processing apparatus according to one aspect of the present disclosure includes a chamber, a substrate support disposed within the chamber, the substrate support comprising a lower electrode, a substrate support surface for supporting a substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface, an upper electrode disposed above the lower electrode, and a power supply unit for supplying two or more powers of different frequencies, the power supply unit comprising a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from a gas in the chamber, and at least one bias power supply configured to supply one or more bias powers of different frequencies to the lower electrode, at least one variable passive component electrically connected to the edge ring, and at least one bypass circuit configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one of the bias powers to the edge ring. [Effects of the Invention] 【0006】 According to this disclosure, the incidence angle of ions in the plasma to the edge region of the substrate can be appropriately controlled during plasma processing. [Brief explanation of the drawing] 【0007】 [Figure 1] This is a longitudinal cross-sectional view showing a schematic configuration of the etching apparatus according to this embodiment. [Figure 2A] This is a longitudinal cross-sectional view showing a schematic configuration of the area around the edge ring according to this embodiment. [Figure 2B] This is a longitudinal cross-sectional view showing a schematic configuration of the area around the edge ring according to this embodiment. [Figure 3A] This diagram illustrates the change in sheath shape and the resulting tilt in the ion incidence direction due to wear of the edge ring. [Figure 3B]This diagram illustrates the change in sheath shape and the resulting tilt in the ion incidence direction due to wear of the edge ring. [Figure 4A] This is an explanatory diagram illustrating the change in the shape of the sheath and the occurrence of a tilt in the direction of ion incidence. [Figure 4B] This is an explanatory diagram illustrating the change in the shape of the sheath and the occurrence of a tilt in the direction of ion incidence. [Figure 5] This is an explanatory diagram showing how the tilt angle changes when the initial tilt angle is not adjusted. [Figure 6] This is an explanatory diagram showing how the tilt angle changes when adjusting the initial tilt angle. [Figure 7] This is an explanatory diagram showing the control range of the tilt angle using the tilt control knob. [Figure 8A] This is an explanatory diagram showing an example of a bypass circuit layout. [Figure 8B] This is an explanatory diagram showing an example of a bypass circuit layout. [Figure 9A] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 9B] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 9C] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 9D] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 9E] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 9F] This is an explanatory diagram showing an example configuration of a bypass circuit. [Figure 10] This is an explanatory diagram showing an example of a method for controlling the tilt angle. [Figure 11] This is an explanatory diagram showing an example of a method for controlling the tilt angle. [Figure 12] This is an explanatory diagram showing an example of a method for controlling the tilt angle. [Figure 13] This is an explanatory diagram showing an example of a method for controlling the tilt angle. [Figure 14] This is an explanatory diagram showing an example of a method for controlling the tilt angle. [Figure 15] It is an explanatory diagram showing an example of a tilt angle control method. [Figure 16] It is an explanatory diagram showing an example of a tilt angle control method. [Figure 17] It is an explanatory diagram showing an example of a tilt angle control method. [Figure 18] It is an explanatory diagram showing an example of the configuration of a bypass circuit and a tilt control knob. [Figure 19] It is an explanatory diagram showing an example of the configuration of a bypass circuit and a tilt control knob. [Figure 20] It is an explanatory diagram showing an example of the configuration of a bypass circuit and a tilt control knob. [Figure 21A] It is an explanatory diagram showing an example of the configuration of a bypass circuit and a tilt control knob. [Figure 21B] It is an explanatory diagram showing an example of the configuration of a bypass circuit and a tilt control knob. [Figure 22] It is a longitudinal sectional view showing an outline of the configuration around an edge ring according to another embodiment. [Figure 23A] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 23B] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 23C] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 23D] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 23E] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 23F] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24A] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24B] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24C] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24D] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24E] It is a longitudinal sectional view showing an example of the configuration of a connection part. [Figure 24F] This is a longitudinal cross-sectional view showing an example of the configuration of the connection section. [Figure 24G] This is a longitudinal cross-sectional view showing an example of the configuration of the connection section. [Figure 25A] This is a plan view showing an example of the configuration of the connection section. [Figure 25B] This is a plan view showing an example of the configuration of the connection section. [Figure 25C] This is a plan view showing an example of the configuration of the connection section. [Figure 26A] This is a schematic diagram illustrating an example of the configuration of the connection section and RF filter. [Figure 26B] This is a schematic diagram illustrating an example of the configuration of the connection section and RF filter. [Figure 26C] This is a schematic diagram illustrating an example of the configuration of the connection section and RF filter. [Figure 27A] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 27B] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 27C] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 27D] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 28A] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 28B] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 28C] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Figure 28D] This is a longitudinal cross-sectional view showing an example of the configuration of the connection part and the lifting device. [Modes for carrying out the invention] 【0008】 In the semiconductor device manufacturing process, semiconductor wafers (hereinafter referred to as "wafers") undergo plasma processing such as etching. In plasma processing, plasma is generated by exciting a processing gas, and the wafer is processed using this plasma. 【0009】 Plasma processing is performed in a plasma processing apparatus. A plasma processing apparatus typically comprises a chamber, a stage, and a radio frequency (RF) power supply. In one example, the RF power supply comprises a first RF power supply and a second RF power supply. The first RF power supply provides first RF power to generate plasma from the gas in the chamber. The second RF power supply provides second RF power for biasing to the lower electrode to draw ions into the wafer. The stage is located within the chamber. The stage has a lower electrode and an electrostatic chuck. In one example, an edge ring is positioned on the electrostatic chuck, surrounding the wafer placed on the chuck. The edge ring is provided to improve the uniformity of the plasma processing on the wafer. 【0010】 As the plasma treatment process progresses, the edge ring wears down, and its thickness decreases. This decrease in edge ring thickness alters the shape of the sheath above the edge ring and the wafer edge region. This change in sheath shape causes the ion incidence direction in the wafer edge region to tilt relative to the vertical. As a result, the recesses formed in the wafer edge region become tilted relative to the wafer thickness direction. 【0011】 In order to form a recess extending in the thickness direction of the wafer in the edge region of the wafer, that is, to control the tilt angle, which is the inclination of the recess with respect to the thickness direction of the wafer W, it is necessary to adjust the inclination of the direction of ion incidence into the wafer edge region. Therefore, in order to control the direction of ion incidence into the edge region (direction of the ion flux), for example, as described above in Patent Document 1, it is proposed to generate capacitance between the electrodes of the bonding ring and the edge ring. 【0012】 Here, when controlling the tilt angle for each of multiple high-frequency powers, the initial tilt angle before plasma processing (hereinafter referred to as the "initial tilt angle") may differ for each frequency. The initial tilt angle is, for example, the tilt angle when the etching apparatus 1 is started up or when the etching apparatus 1 is operated after maintenance, and once the initial tilt angle has been adjusted, it does not need to be adjusted again. However, if the initial tilt angle varies in this way, it may be difficult to control the tilt angle to be uniform for each frequency, even if the incidence angle is adjusted by generating the capacitance as disclosed in, for example, Patent Document 1. 【0013】 The technology described herein adjusts the initial tilt angle in the edge region of the substrate during etching to appropriately control the tilt angle in the said edge region. 【0014】 Hereinafter, the etching apparatus and etching method as a plasma processing apparatus according to this embodiment will be described with reference to the drawings. In this specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant explanations will be omitted. 【0015】 <Etching equipment> First, the etching apparatus according to this embodiment will be described. Figure 1 is a longitudinal cross-sectional view showing a schematic configuration of the etching apparatus 1. Figures 2A and 2B are longitudinal cross-sectional views showing a schematic configuration of the area around the edge ring, respectively. The etching apparatus 1 is a capacitively coupled etching apparatus. The etching apparatus 1 performs etching on a wafer W, which is the substrate. 【0016】 As shown in Figure 1, the etching apparatus 1 has a substantially cylindrical chamber 10. The chamber 10 defines a processing space S in which plasma is generated. The chamber 10 is made of, for example, aluminum. The chamber 10 is connected to ground potential. 【0017】 Inside the chamber 10 is a stage 11, which serves as a substrate support on which the wafer W is placed. The stage 11 has a lower electrode 12, an electrostatic chuck 13, and an edge ring 14. An electrode plate (not shown), made of aluminum, for example, may be provided on the lower surface of the lower electrode 12. 【0018】 The lower electrode 12 is made of a conductive material, such as a metal like aluminum, and has a roughly disc shape. 【0019】 The stage 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 13, edge ring 14, and wafer W to a desired temperature. The temperature control module may include a heater, a flow path, or a combination thereof. A temperature control medium, such as a refrigerant or heat transfer gas, flows through the flow path. 【0020】 In one example, a flow channel 15a is formed inside the lower electrode 12. A temperature-controlled medium is supplied to the flow channel 15a from a chiller unit (not shown) located outside the chamber 10 via an inlet pipe 15b. The temperature-controlled medium supplied to the flow channel 15a returns to the chiller unit via an outlet flow channel 15c. By circulating a temperature-controlled medium, such as a coolant like cooling water, in the flow channel 15a, the electrostatic chuck 13, edge ring 14, and wafer W can be cooled to a desired temperature. 【0021】 The electrostatic chuck 13 is provided on the lower electrode 12. In one example, the electrostatic chuck 13 is a component configured to hold both the wafer W and the edge ring 14 by electrostatic force. The upper surface of the central part of the electrostatic chuck 13 is higher than the upper surface of the peripheral part. The upper surface of the central part of the electrostatic chuck 13 serves as a wafer support surface for supporting the wafer W, and in one example, the upper surface of the peripheral part of the electrostatic chuck 13 serves as an edge ring support surface for supporting the edge ring 14. The lower electrode 12 may be provided inside the electrostatic chuck 13. 【0022】 In one example, a first electrode 16a for adsorbing and holding a wafer W is provided in the central part of the electrostatic chuck 13. A second electrode 16b for adsorbing and holding an edge ring 14 is provided in the peripheral part of the electrostatic chuck 13. The electrostatic chuck 13 has a configuration in which electrodes 16a and 16b are sandwiched between insulating materials made of insulating material. 【0023】 A DC voltage from a DC power supply (not shown) is applied to the first electrode 16a. The resulting electrostatic force causes the wafer W to be attracted and held on the upper surface of the central part of the electrostatic chuck 13. Similarly, a DC voltage from a DC power supply (not shown) is applied to the second electrode 16b. In one example, the resulting electrostatic force causes the edge ring 14 to be attracted and held on the upper surface of the peripheral part of the electrostatic chuck 13. 【0024】 In this embodiment, the central part of the electrostatic chuck 13 on which the first electrode 16a is provided and the peripheral part on which the second electrode 16b is provided are integrated, but these central and peripheral parts may be separate. Also, both the first electrode 16a and the second electrode 16b may be unipolar or bipolar. 【0025】 Furthermore, in this embodiment, the edge ring 14 is electrostatically attracted to the electrostatic chuck 13 by applying a DC voltage to the second electrode 16b, but the method of holding the edge ring 14 is not limited to this. For example, the edge ring 14 may be held by adsorption using an adsorption sheet, or the edge ring 14 may be held by clamping. Alternatively, the edge ring 14 may be held by its own weight. 【0026】 The edge ring 14 is an annular member positioned to surround the wafer W placed on the upper surface of the central part of the electrostatic chuck 13. The edge ring 14 is provided to improve the uniformity of etching. For this reason, the edge ring 14 is made of a material appropriately selected according to the etching process, and is conductive, and may be made of, for example, Si or SiC. 【0027】 The stage 11, configured as described above, is fastened to a substantially cylindrical support member 17 provided at the bottom of the chamber 10. The support member 17 is made of an insulator such as ceramic or quartz. 【0028】 A shower head 20 is provided above the stage 11, facing the stage 11. The shower head 20 has an electrode plate 21 positioned facing the processing space S, and an electrode support 22 provided above the electrode plate 21. The electrode plate 21 functions as a pair of upper electrodes with the lower electrode 12. When the first high-frequency power supply 50 is electrically coupled to the lower electrode 12, as will be described later, the shower head 20 is connected to ground potential. The shower head 20 is supported on the upper part (ceiling surface) of the chamber 10 via an insulating shielding member 23. 【0029】 The electrode plate 21 has a plurality of gas outlets 21a formed therein for supplying the processing gas sent from the gas diffusion chamber 22a (described later) to the processing space S. The electrode plate 21 is made of, for example, a conductor or semiconductor having low electrical resistivity that generates little Joule heat. 【0030】 The electrode support 22 detachably supports the electrode plate 21. The electrode support 22 has a structure in which a plasma-resistant film is formed on the surface of a conductive material such as aluminum. This film may be formed by anodizing or a ceramic film such as yttrium oxide. A gas diffusion chamber 22a is formed inside the electrode support 22. Multiple gas flow holes 22b that communicate with the gas outlet 21a are formed in the gas diffusion chamber 22a. In addition, a gas introduction hole 22c that is connected to a gas supply pipe 33, which will be described later, is formed in the gas diffusion chamber 22a. 【0031】 Furthermore, the electrode support 22 is connected to a group of gas supply sources 30 that supply processed gas to the gas diffusion chamber 22a via a group of flow control devices 31, a group of valves 32, a gas supply pipe 33, and a gas inlet hole 22c. 【0032】 The gas supply source group 30 has multiple types of gas supply sources necessary for etching. The flow control equipment group 31 includes multiple flow controllers, and the valve group 32 includes multiple valves. Each of the multiple flow controllers in the flow control equipment group 31 is either a mass flow controller or a pressure-controlled flow controller. In the etching apparatus 1, processing gas from one or more gas supply sources selected from the gas supply source group 30 is supplied to the gas diffusion chamber 22a via the flow control equipment group 31, the valve group 32, the gas supply pipe 33, and the gas inlet hole 22c. The processing gas supplied to the gas diffusion chamber 22a is then dispersed in a shower-like manner into the processing space S via the gas flow hole 22b and the gas outlet 21a. 【0033】 A baffle plate 40 is provided at the bottom of the chamber 10, between the inner wall of the chamber 10 and the support member 17. The baffle plate 40 is constructed, for example, by coating aluminum with ceramics such as yttrium oxide. Multiple through holes are formed in the baffle plate 40. The processing space S is connected to an exhaust port 41 via the baffle plate 40. An exhaust device 42, such as a vacuum pump, is connected to the exhaust port 41, and the exhaust device 42 is configured to reduce the pressure inside the processing space S. 【0034】 Furthermore, a wafer loading / unloading port 43 is formed in the side wall of the chamber 10, and this port 43 can be opened and closed by a gate valve 44. 【0035】 As shown in Figures 1, 2A, and 2B, the etching apparatus 1 further includes a first high-frequency power supply 50 as a source power supply, a second high-frequency power supply 51 as a bias power supply, a third high-frequency power supply 52 as a bias power supply, and a matching circuit 53. The first high-frequency power supply 50, the second high-frequency power supply 51, and the third high-frequency power supply 52 are each coupled to the lower electrode 12 via a first matching circuit 54, a second matching circuit 55, and a third matching circuit 56. In this embodiment, the first matching circuit 54, the second matching circuit 55, and the third matching circuit 56 are provided inside one matching circuit 53, but their arrangement is not limited. For example, they may be provided inside separate matching circuits or outside of matching circuits. Furthermore, the first high-frequency power supply 50, the second high-frequency power supply 51, and the third high-frequency power supply 52 constitute the power supply unit in this disclosure. 【0036】 The first high-frequency power supply 50 generates a first high-frequency power HF, which is the source RF power (source power) for plasma generation, and supplies the first high-frequency power HF to the lower electrode 12. The first high-frequency power HF may be a first frequency in the range of 27 MHz to 100 MHz, and in one example it is 40 MHz. The first high-frequency power supply 50 is coupled to the lower electrode 12 via the first matching circuit 54 of the matching unit 53. The first matching circuit 54 is a circuit for matching the output impedance of the first high-frequency power supply 50 with the input impedance of the load side (lower electrode 12 side). Note that the first high-frequency power supply 50 does not have to be electrically coupled to the lower electrode 12, and may be coupled to the upper electrode, the shower head 20, via the first matching circuit 54. Alternatively, instead of the first high-frequency power supply 50, a pulse power supply configured to apply a pulse voltage other than high-frequency power to the lower electrode 12 may be used. This pulse power supply is similar to the pulse power supplies used in place of the second high-frequency power supply 51 and the third high-frequency power supply 52 described later. 【0037】 The second high-frequency power supply 51 generates a second high-frequency power LF1, which is a bias RF power (bias power) for drawing ions into the wafer W, and supplies the second high-frequency power LF1 to the lower electrode 12. The second high-frequency power LF1 may be a second frequency in the range of 100 kHz to 15 MHz, and in one example it is 400 kHz. The second high-frequency power supply 51 is coupled to the lower electrode 12 via a second matching circuit 55 of the matching unit 53. The second matching circuit 55 is a circuit for matching the output impedance of the second high-frequency power supply 51 with the input impedance of the load side (lower electrode 12 side). 【0038】 The third high-frequency power supply 52 generates a third high-frequency power LF2, which is a bias RF power (bias power) for drawing ions into the wafer W, and supplies the third high-frequency power LF2 to the lower electrode 12. The third high-frequency power LF2 may be a third frequency in the range of 100 kHz to 15 MHz, and unlike the second frequency, is 13 MHz in one example. The third high-frequency power supply 52 is coupled to the lower electrode 12 via a third matching circuit 56 of the matching unit 53. The third matching circuit 56 is a circuit for matching the output impedance of the third high-frequency power supply 52 with the input impedance of the load side (lower electrode 12 side). 【0039】 In addition, instead of the second high-frequency power supply 51 and the third high-frequency power supply 52, a pulse power supply configured to apply a pulse voltage other than high-frequency power to the lower electrode 12 may be used. Here, a pulse voltage is a pulse-shaped voltage whose magnitude changes periodically. The pulse power supply may be a DC power supply. The pulse power supply may be configured so that the power supply itself generates the pulse voltage, or it may be configured to include a DC power supply and a device (pulse generation unit) downstream of the DC power supply that pulses the voltage. In one example, the pulse voltage is applied to the lower electrode 12 so that a negative potential is generated on the wafer W. The pulse voltage may be a square wave, a triangular wave, an impulse, or have any other waveform. The frequency of the pulse voltage (pulse frequency) may be in the range of 100 kHz to 2 MHz. The high-frequency power LF1, LF2 or pulse voltage may be supplied to or applied to a bias electrode provided inside the electrostatic chuck 13. 【0040】 The etching apparatus 1 further comprises a DC (Direct Current) power supply 60, a switching unit 61, a first RF filter 62, and a second RF filter 63 (corresponding to the third RF filter in this disclosure). The DC power supply 60 is electrically connected to the edge ring 14 from the DC power supply 60 side via the switching unit 61, the second RF filter 63, and the first RF filter 62. The DC power supply 60 is connected to ground potential. 【0041】 The DC power supply 60 is a power supply that generates a negative polarity DC voltage applied to the edge ring 14. Furthermore, the DC power supply 60 is a variable DC power supply, and the level of the DC voltage can be adjusted. 【0042】 The switching unit 61 is configured to stop the application of DC voltage from the DC power supply 60 to the edge ring 14. The circuit configuration of the switching unit 61 can be appropriately designed by a person skilled in the art. 【0043】 The first RF filter 62 and the second RF filter 63 are filters that attenuate high-frequency power. The first RF filter 62 attenuates, for example, a first high-frequency power HF of 40 MHz from a first high-frequency power supply 50. The second RF filter 63 attenuates, for example, a second high-frequency power LF1 of 400 kHz from a second high-frequency power supply 51 or a third high-frequency power LF2 of 13 MHz from a third high-frequency power supply 52. 【0044】 In one example, the second RF filter 63 is configured to have a variable impedance. That is, the second RF filter 63 includes at least one variable passive element, and its impedance is variable. The variable passive element may be, for example, a coil (inductor) or a capacitor. Furthermore, it is not limited to coils and capacitors; any variable impedance element such as a diode can achieve the same function. The number and position of the variable passive elements can also be appropriately designed by a person skilled in the art. Moreover, the element itself does not need to be variable; for example, the impedance can be varied by providing multiple elements with fixed impedances and switching the combination of fixed-impedance elements using a switching circuit. The circuit configuration including this second RF filter 63 and the circuit configuration including the first RF filter 62 can each be appropriately designed by a person skilled in the art. 【0045】 The etching apparatus 1 further includes a bypass circuit 70. In one example, the bypass circuit 70 is connected to a path 57 between the matching unit 53 and the lower electrode 12, and to a path 64 between the second RF filter 63 and the edge ring 14. The arrangement of the bypass circuit 70 is not limited to this example. Also, in this example, there is one bypass circuit 70, but there may be multiple. Variations in the arrangement of the bypass circuit 70 and variations in the combination of bypass circuits 70 will be described later. 【0046】 The bypass circuit 70 bypasses high-frequency power of a specific frequency to increase the power supply to the edge ring 14. Specifically, the bypass circuit 70 selectively passes high-frequency power of the frequency targeted for adjustment of the initial tilt angle from a group consisting of first to third high-frequency powers HF, LF1, and LF2 of multiple frequencies that are subject to tilt angle control. The bypass circuit 70 also adjusts the amount of high-frequency power that passes through (the magnitude of the high-frequency power), that is, the amount of power supplied to the edge ring 14. 【0047】 Thus, the bypass circuit 70 has a frequency selection function and a power transmission amount determination function, but its circuit configuration can be arbitrarily designed by a person skilled in the art. In one example, the bypass circuit 70 may have a circuit that blocks the passage of high-frequency power of a specific frequency, such as a coil (inductor), in order to achieve the frequency selection function. In addition, the bypass circuit 70 may have an element that determines the amount of high-frequency power that passes through, such as a capacitor, in order to achieve the power transmission amount determination function. 【0048】 The etching apparatus 1 further includes a lifting device 80 for raising and lowering the edge ring 14. The lifting device 80 includes a lifting pin 81 that supports and moves the edge ring 14 up and down, and a drive source 82 that moves the lifting pin 81 up and down. 【0049】 The lifting pin 81 extends vertically from the lower surface of the edge ring 14 and is provided penetrating the electrostatic chuck 13, the lower electrode 12, the support member 17, and the bottom of the chamber 10. The space between the lifting pin 81 and the chamber 10 is sealed to seal the inside of the chamber 10. At least the surface of the lifting pin 81 is made of an insulator. 【0050】 The drive source 82 is located outside the chamber 10. The drive source 82, for example, incorporates a motor to raise and lower the lifting pin 81. In other words, the lifting device 80 allows the edge ring 14 to move up and down between a state where it is placed on the electrostatic chuck 13, as shown in Figure 2A, and a state where it is separated from the electrostatic chuck 13, as shown in Figure 2B. 【0051】 Furthermore, the etching apparatus 1 may also include a measuring instrument (not shown) for measuring the self-bias voltage of the edge ring 14 (or the self-bias voltage of the lower electrode 12 or the wafer W). The configuration of the measuring instrument can be appropriately designed by a person skilled in the art. 【0052】 The etching apparatus 1 described above is equipped with a control unit 100. The control unit 100 is, for example, a computer equipped with a CPU, memory, etc., and has a program storage unit (not shown). The program storage unit stores a program that controls etching in the etching apparatus 1. The program may have been recorded on a storage medium readable by the computer and installed from that storage medium to the control unit 100. Furthermore, the storage medium may be temporary or permanent. 【0053】 <Etching Method> Next, we will describe the etching process performed using the etching apparatus 1 configured as described above. 【0054】 First, the wafer W is brought into the chamber 10 and placed on the electrostatic chuck 13. Then, by applying a DC voltage to the first electrode 16a of the electrostatic chuck 13, the wafer W is electrostatically attracted to and held by the electrostatic chuck 13 due to Coulomb force. After the wafer W is brought in, the inside of the chamber 10 is depressurized to a desired vacuum level by the exhaust device 42. 【0055】 Next, a processing gas is supplied from the gas supply source group 30 to the processing space S via the shower head 20. A first high-frequency power HF for plasma generation is supplied to the lower electrode 12 by the first high-frequency power supply 50, exciting the processing gas and generating plasma. At this time, a second high-frequency power supply 51 and a third high-frequency power supply 52 may be supplied for ion drawing in a second high-frequency power LF1 and a third high-frequency power LF2, respectively. The generated plasma then etches the wafer W. 【0056】 When terminating the etching process, first, the supply of the first high-frequency power HF from the first high-frequency power supply 50 and the supply of processing gas from the gas supply source group 30 are stopped. If high-frequency powers LF1 and LF2 were supplied during etching, the supply of these high-frequency powers LF1 and LF2 is also stopped. Next, the supply of heat transfer gas to the back surface of the wafer W is stopped, and the adsorption and holding of the wafer W by the electrostatic chuck 13 is stopped. 【0057】 Subsequently, the wafer W is removed from the chamber 10, and the series of etching processes on the wafer W is completed. 【0058】 In etching, the plasma may be generated using only the second high-frequency power LF1 from the second high-frequency power supply 51 or the third high-frequency power LF2 from the third high-frequency power supply 52, without using the first high-frequency power HF from the first high-frequency power supply 50. 【0059】 <Explanation of Tilt Angle> The tilt angle is the inclination (angle) of the recess formed by etching in the edge region of the wafer W with respect to the thickness direction of the wafer W. The tilt angle is approximately the same as the inclination of the ion incidence direction to the edge region of the wafer W with respect to the vertical direction (angle of ion incidence). In the following explanation, the direction radially inward (towards the center) with respect to the thickness direction (vertical direction) of the wafer W is referred to as the inner side, and the direction radially outward with respect to the thickness direction of the wafer W is referred to as the outer side. 【0060】 Figures 3A and 3B are explanatory diagrams illustrating the change in sheath shape and the resulting tilt in the ion incidence direction due to wear of the edge ring. In Figure 3A, the solid line shows the edge ring 14 in an unworn state. The dotted line shows the edge ring 14 after wear has occurred and its thickness has decreased. Also, the solid line in Figure 3A shows the shape of the sheath SH when the edge ring 14 is unworn. The dotted line shows the shape of the sheath SH when the edge ring 14 is worn. Furthermore, in Figure 3A, the arrows indicate the ion incidence direction when the edge ring 14 is worn. 【0061】 As shown in Figure 3A, in one example, when the edge ring 14 is not worn, the shape of the sheath SH is kept flat above the wafer W and the edge ring 14. Therefore, ions are incident on the entire surface of the wafer W in a direction approximately perpendicular (vertical direction). Consequently, the tilt angle is 0 degrees. 【0062】 On the other hand, as the edge ring 14 wears down and its thickness decreases, the thickness of the sheath SH decreases in the edge region of the wafer W and above the edge ring 14, and the shape of the sheath SH changes to a downward convex shape. As a result, the direction of ion incidence on the edge region of the wafer W becomes inclined with respect to the vertical. In the following explanation, the phenomenon in which the recess formed by etching tilts inward when the direction of ion incidence is inclined radially inward (towards the center) with respect to the vertical is called inner tilt. In Figure 3B, the direction of ion incidence is inclined inward by an angle θ1, and the recess is also inclined inward by an angle θ1. Note that the cause of inner tilt is not limited to the wear of the edge ring 14 as described above. For example, if the bias voltage generated on the edge ring 14 is lower than the voltage on the wafer W side, inner tilt occurs in the initial state. Also, for example, the edge ring 14 may be intentionally adjusted to be in an inner tilt state in its initial state, and the tilt angle may be corrected by adjusting the drive amount of the lifting device 80, which will be described later. 【0063】 As shown in Figures 4A and 4B, the thickness of the sheath SH increases in the edge region of the wafer W and above the edge ring 14 relative to the central region of the wafer W, and the shape of the sheath SH may become upward convex. For example, if the bias voltage generated at the edge ring 14 is high, the shape of the sheath SH may become upward convex. In Figure 4A, the arrow indicates the direction of ion incidence. In the following explanation, the phenomenon in which the recess formed by etching tilts outward when the direction of ion incidence is tilted radially outward with respect to the vertical is called outer tilt. In Figure 4B, the direction of ion incidence is tilted outward by an angle θ2, and the recess is also tilted outward by an angle θ2. 【0064】 As described above, except in the cases shown in Figures 4A and 4B, when etching is performed and the edge ring 14 is worn down, the tilt angle in the edge region of the wafer W tilts inward, as shown in Figures 3A and 3B. For this reason, in one example, the tilt angle is controlled and corrected to the outer side. The tilt angle is controlled by adjusting the impedance of the second RF filter 63, adjusting the DC voltage from the DC power supply 60, adjusting the drive amount of the lifting device 80, or a combination thereof. In the following description, the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80 used to control the tilt angle may be collectively referred to as the "tilt control knob." The specific method of controlling the tilt angle using the tilt control knob will be described later. 【0065】 <How to adjust the initial tilt angle> As described above, when the tilt angle is controlled outward using the tilt control knob, the initial tilt angle in the initial state before etching is set to 0 degrees or an angle that results in a slight inward tilt in the initial state. The initial state is, for example, when the etching apparatus 1 is started up or when the etching apparatus 1 is operated after maintenance, and before etching is performed on the wafer W. 【0066】 Conventionally, the initial tilt angle was adjusted, for example, by adjusting the thickness of the edge ring 14. Alternatively, the initial tilt angle was adjusted, for example, by changing the material or thickness of the electrostatic chuck 13. In other words, the initial tilt angle was adjusted by changing the device configuration (hardware). 【0067】 Here, when controlling the tilt angle for multiple high-frequency powers, for example, three frequencies (HF, LF1, LF2), the sheath thickness generated by the power supplied to the edge ring 14 differs for each frequency. As a result, as shown in Figure 5, the initial tilt angle differs for each of the first to third frequencies. Hereafter, the initial tilt angle for the first frequency will be referred to as the first initial tilt angle, the initial tilt angle for the second frequency as the second initial tilt angle, and the initial tilt angle for the third frequency as the third initial tilt angle. In Figure 5, the vertical axis represents the tilt angle, with the positive side (up) of the tilt angle Δ0 (zero) being the outer side and the negative side (down) being the inner side. 90 degrees (in parentheses) on the vertical axis indicates the thickness direction of the wafer W, and Δ0 (zero) degrees indicates that it is not tilted from the thickness direction. The horizontal axis in Figure 5 represents the adjustment amount of the tilt control knob. In Figure 5, the symbols ●, ▲, and ■ represent the first to third initial tilt angles, respectively. In Figure 5, the lines extending from the first to third initial tilt angles schematically show the changes in the tilt angle by adjusting the tilt control knob. 【0068】 In cases where the initial tilt angles of the first to third instruments differ for each frequency, simply changing the device configuration, as in conventional methods, does not allow for adjustment of the initial tilt angles of other frequencies even if the initial tilt angle of one frequency is adjusted. In other words, it is not possible to properly adjust all of the initial tilt angles of the first to third instruments. Furthermore, when the initial tilt angles of the first to third instruments differ for each frequency, even if the tilt angle is controlled using the tilt control knob, it may not be possible to properly control the tilt angle to, for example, 0 degrees. 【0069】 Therefore, in the etching apparatus 1 of this embodiment, the initial tilt angle is adjusted for each frequency using a bypass circuit 70. That is, the bypass circuit 70 bypasses high-frequency power of a specific frequency, increasing the amount of power supplied to the edge ring 14, thereby adjusting the initial tilt angle in the edge region of the wafer W. Specifically, the bypass circuit 70 selectively passes high-frequency power of the frequency for which the initial tilt angle is to be adjusted, from among a plurality of high-frequency powers whose tilt angle is to be controlled. The bypass circuit 70 also adjusts the amount of high-frequency power that passes through, i.e., the amount of power supplied to the edge ring 14. 【0070】 For example, in the example shown in Figure 5, the first to third initial tilt angles are different, and the second and third initial tilt angles are the ones to be adjusted. In this case, the bypass circuit 70 allows the second high-frequency power LF1 and the third high-frequency power LF2 of the first to third high-frequency powers HF, LF1, and LF2 to pass through the edge ring 14. At this time, the amount of the second high-frequency power LF1 and the amount of the third high-frequency power LF2 that pass through are set to amounts corresponding to the adjustment range of the initial tilt angle. As a result, the amount of the second high-frequency power LF1 and the third high-frequency power LF2 supplied to the edge ring 14 increases, and the second tilt angle and the third initial tilt angle are adjusted to the outer side, as shown in Figure 6. Then, the first to third initial tilt angles can be adjusted to be approximately the same. 【0071】 As described above, in this embodiment, the first to third initial tilt angles can be independently adjusted using the bypass circuit 70 during initial states such as when the etching apparatus 1 is manufactured or adjusted, so that these first to third initial tilt angles can be adjusted to be approximately the same. As a result, when etching is performed thereafter, the tilt angle can be appropriately controlled to, for example, 0 degrees for each of the first to third frequencies by adjusting the tilt control knob. 【0072】 Note that if you adjust the first to third initial tilt angles in the initial state, you will generally not change the first to third initial tilt angles during subsequent etching. 【0073】 Furthermore, according to this embodiment, in the initial state, the first to third initial tilt angles are adjusted using a bypass circuit 70 separate from the tilt control knob, so that the control range of the tilt angle by the tilt control knob can be widened during subsequent etching. 【0074】 Figure 7 is an explanatory diagram illustrating the effect of expanding the tilt angle control range. (a) shows the tilt angle control range in the comparative example, and (b) shows the tilt angle control range in the embodiment of this model. That is, Figure 7(a) corresponds to the tilt angle shown in Figure 5, and Figure 7(b) corresponds to the tilt angle shown in Figure 6. In Figure 7, the dotted line indicates the tilt angle control range using the tilt control knob. On the other hand, the solid line with circles at both ends represents the tilt angle control range in which the final tilt angle is within the acceptable range, or in other words, the tilt angle control range that can actually be used. 【0075】 As shown in Figure 7(a), in the comparative example, the first to third initial tilt angles are not individually adjusted, and these first to third initial tilt angles are different. In this case, the second initial tilt angle is shifted inward, so the actually usable tilt angle control range (solid line) becomes narrower than the tilt angle control range (dotted line) using the tilt control knob. Furthermore, the third initial tilt angle is shifted even further inward than the second tilt angle, so the actually usable tilt angle control range (solid line) becomes even narrower. Thus, because the first to third initial tilt angles are not properly adjusted, the tilt angle control range becomes narrower, and the tilt angle control effect of the tilt control knob becomes smaller. 【0076】 In contrast, as shown in Figure 7(b), in this embodiment, the first to third initial tilt angles are adjusted to be approximately the same using the bypass circuit 70. That is, the initial tilt angle is adjusted using only the bypass circuit 70, and subsequent tilt angle control is performed using only the tilt control knob. In this case, the second initial tilt angle is shifted outward to adjust to the desired angle, thereby widening the usable tilt angle control range (solid line). Furthermore, the third initial tilt angle is shifted even further outward than the second tilt angle to adjust to the desired angle, thereby further widening the usable tilt angle control range (solid line). Thus, in this embodiment, the tilt angle control range can be widened by making maximum use of the tilt angle control range provided by the tilt control knob. 【0077】 In this embodiment, the tilt angles for all of the first to third high-frequency powers HF, LF1, and LF2 of the three frequencies were controlled, but the number of controlled elements is not limited to this. For example, the technology of this disclosure can be applied even if the tilt angles for two high-frequency powers are controlled. In other words, the technology of this disclosure is useful when the tilt angles for two or more high-frequency powers are controlled. 【0078】 Furthermore, the technology of this disclosure can also be applied when the tilt angle for a single high-frequency power is to be controlled. Conventionally, the initial tilt angle was adjusted by changing the device configuration as described above, but in this embodiment, the initial tilt angle is adjusted using the bypass circuit 70, making it easier to adjust the initial tilt angle. 【0079】 <Variations of bypass circuits> Next, we will explain the variations in the arrangement and combination of bypass circuits. 【0080】 [Bypass circuit layout] In the above embodiment, as shown in Figure 2A, the bypass circuit 70 is connected to the path 57 between the matching circuit 53 and the lower electrode 12, and to the path 64 between the second RF filter 63 and the edge ring 14. However, the placement of the bypass circuit 70 is not limited to this. The bypass circuit 70 can be connected to the same location as the matching circuit 53 or to the path 57 between the matching circuit 53 and the lower electrode 12. The bypass circuit 70 is placed in this manner to include the area downstream of the bypass circuit 70 in the matching range. The bypass circuit 70 can also be connected to the RF filters 62 and 63, or to the path 64 between the RF filters 62 and 63 and the edge ring 14. 【0081】 For example, as shown in Figure 8A, the bypass circuit 70 may be located inside the second RF filter 63. Alternatively, as shown in Figure 8B, the bypass circuit 70 may be located inside the first RF filter 62. Although not shown, the bypass circuit 70 may also be located inside the matching circuit 53. Furthermore, although not shown, the bypass circuit 70 may be connected to the matching circuit 53 and the second RF filter 63, or to the matching circuit 53 and the DC power supply 60. Thus, the bypass circuit 70 is not location-dependent. 【0082】 [Bypass circuit combinations] In the embodiment described above, as shown in Figure 2A, the bypass circuit 70 is provided in common for the first to third high-frequency powers HF, LF1, and LF2 of multiple frequencies, but the combination of bypass circuits 70 is not limited to this. For example, the bypass circuit 70 may be provided independently for each of the three first to third high-frequency powers HF, LF1, and LF2 of the three frequencies. Also, for example, the bypass circuit 70 does not need to be provided for all of the first to third high-frequency powers HF, LF1, and LF2 whose tilt angle is to be controlled. For example, the initial tilt angle may be adjusted using the bypass circuit 70 for some high-frequency powers, and the initial tilt angle may be adjusted by changing the device configuration as in the conventional method for some high-frequency powers. Alternatively, there may be only one bypass circuit 70 for two or more high-frequency powers. If these frequencies are close together, it is not necessary to provide multiple bypass circuits 70. These combinations of bypass circuits 70 are arbitrary. 【0083】 For example, as shown in Figure 9A, a bypass circuit 70a that passes the first high-frequency power HF, a bypass circuit 70b that passes the second high-frequency power LF1, and a bypass circuit 70c that passes the third high-frequency power LF2 may be provided. This is the case when all of the first to third initial tilt angles are adjusted. Alternatively, as shown in Figure 9B, only the bypass circuit 70a that passes the first high-frequency power HF and the bypass circuit 70b that passes the second high-frequency power LF1 may be provided. This is the case when the first initial tilt angle and the second initial tilt angle are adjusted. Or, as shown in Figure 9C, only the bypass circuit 70b that passes the second high-frequency power LF1 and the bypass circuit 70c that passes the third high-frequency power LF2 may be provided. This is the case when the second initial tilt angle and the third initial tilt angle are adjusted. 【0084】 For example, as shown in Figure 9D, a bypass circuit 70d that passes a first high-frequency power HF and a second high-frequency power LF1, and a bypass circuit 70c that passes a third high-frequency power LF2 may be provided. The bypass circuit 70d adjusts the first initial tilt angle and the second initial tilt angle. Alternatively, as shown in Figure 9E, only the bypass circuit 70d that passes the first high-frequency power HF and the second high-frequency power LF1 may be provided. Or, only the bypass circuit 70c that passes the third high-frequency power LF2 may be provided. 【0085】 <Tilt Angle Control Method> Next, we will explain how to control the tilt angle using a tilt control knob in the etching process described above. The tilt control knob controls one or a combination of the following: adjusting the impedance of the second RF filter 63, adjusting the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80, i.e., (1) to (7) below. The tilt angle is controlled by controlling the incident angle of ions using the tilt control knob. (1) Adjusting the impedance (2) Adjustment of DC voltage (3) Adjustment of drive amount (4) Adjustment of impedance and DC voltage (5) Adjustment of impedance and drive amount (6) Adjustment of DC voltage and drive amount (7) Adjustment of impedance, DC voltage and drive amount 【0086】 (1) Adjusting the impedance The case of adjusting the impedance of the second RF filter 63 will be explained. Figure 10 is an explanatory diagram showing the relationship between the impedance of the second RF filter 63 and the tilt angle correction angle (hereinafter referred to as the "tilt correction angle"). In Figure 10, the vertical axis shows the tilt correction angle, and the horizontal axis shows the impedance of the second RF filter 63. As shown in Figure 10, increasing the impedance of the second RF filter 63 increases the tilt correction angle. In the example shown in Figure 10, the tilt correction angle is increased by increasing the impedance, but depending on the configuration of the second RF filter 63, it is also possible to decrease the tilt correction angle by increasing the impedance. The relationship between impedance and tilt correction angle is not limited, as it depends on the design of the second RF filter 63. 【0087】 The control unit 100 sets the impedance of the second RF filter 63 based on the amount of wear on the edge ring 14 (the decrease in the thickness of the edge ring 14 from its initial value) estimated from the etching process conditions (e.g., processing time) using, for example, a predetermined function or table. That is, the control unit 100 determines the impedance of the second RF filter 63 by inputting the amount of wear on the edge ring 14 into the above function or by referring to the above table using the amount of wear on the edge ring 14. The control unit 100 then changes the voltage generated on the edge ring 14 by changing the impedance of the second RF filter 63. 【0088】 The wear of the edge ring 14 may be estimated based on the etching time of the wafer W, the number of wafers W processed, the thickness of the edge ring 14 measured by a measuring instrument, the change in the mass of the edge ring 14 measured by a measuring instrument, the change in the electrical characteristics around the edge ring 14 (e.g., voltage and current values ​​at any point around the edge ring 14) measured by a measuring instrument, or the change in the electrical characteristics of the edge ring 14 (e.g., the resistance value of the edge ring 14) measured by a measuring instrument. In addition, the impedance of the second RF filter 63 may be adjusted according to the etching time of the wafer W and the number of wafers W processed, regardless of the wear of the edge ring 14. Furthermore, the impedance of the second RF filter 63 may be adjusted according to the etching time of the wafer W and the number of wafers W processed, weighted by high-frequency power. 【0089】 The specific method for controlling the tilt angle by adjusting the impedance of the second RF filter 63 as described above will now be explained. First, the edge ring 14 is placed on the electrostatic chuck 13. At this time, for example, the sheath shape becomes flat in the edge region of the wafer W and above the edge ring 14, and the tilt angle is 0 degrees. 【0090】 Next, etching is performed on the wafer W. As the etching process progresses, the edge ring 14 is worn down and its thickness decreases. As a result, as shown in Figure 3A, the thickness of the sheath SH decreases in the edge region of the wafer W and above the edge ring 14, and the tilt angle changes inward. 【0091】 Therefore, the impedance of the second RF filter 63 is adjusted. Specifically, the impedance of the second RF filter 63 is adjusted according to the amount of wear on the edge ring 14. As a result, the tilt correction angle increases, as shown in Figure 10, and the tilt angle, which was tilted inward, can be changed to the outward side. That is, the shape of the sheath above the edge ring 14 and the edge region of the wafer W is controlled, reducing the inclination of the ion incidence direction to the edge region of the wafer W, and controlling the tilt angle. Then, as described above, by adjusting the second RF filter 63 to the impedance set in the control unit 100, the tilt correction angle can be adjusted to the target angle θ3, and the tilt angle can be corrected to 0 degrees. As a result, a recess substantially parallel to the thickness direction of the wafer W is formed over the entire area of ​​the wafer W. 【0092】 (2) Adjustment of DC voltage This section describes how to adjust the DC voltage from the DC power supply 60. Figure 11 is an explanatory diagram showing the relationship between the DC voltage from the DC power supply 60 and the tilt correction angle. In Figure 11, the vertical axis represents the tilt correction angle, and the horizontal axis represents the DC voltage from the DC power supply 60. As shown in Figure 11, increasing the DC voltage from the DC power supply 60 increases the tilt correction angle. 【0093】 In the DC power supply 60, the DC voltage applied to the edge ring 14 is set to a negative voltage whose absolute value is the sum of the absolute value of the self-bias voltage Vdc and the set value ΔV, i.e., -(|Vdc|+ΔV). The self-bias voltage Vdc is the self-bias voltage of the wafer W, and is the self-bias voltage of the lower electrode 12 when one or both of the high-frequency power supplies are supplied and the DC voltage from the DC power supply 60 is not applied to the lower electrode 12. The set value ΔV is given by the control unit 100. 【0094】 The control unit 100 sets the DC voltage from the DC power supply 60 based on the wear of the edge ring 14, similar to the setting of the impedance of the second RF filter 63 described above. That is, it determines the set value ΔV. 【0095】 The control unit 100 may use the difference between the initial thickness of the edge ring 14 and the thickness of the edge ring 14 measured using a measuring instrument such as a laser measuring instrument or a camera as the wear amount of the edge ring 14 when determining the set value ΔV. Alternatively, the wear amount of the edge ring 14 may be estimated from the change in the mass of the edge ring 14 measured using a measuring instrument such as a mass meter. Or, the control unit 100 may estimate the wear amount of the edge ring 14 from specific parameters using a predetermined function or table for determining the set value ΔV. These specific parameters may be any of the following: self-bias voltage Vdc, peak value Vpp of any of the first to third high-frequency powers HF, LF1, LF2, load impedance, or electrical characteristics of the edge ring 14 or its surroundings. The electrical characteristics of the edge ring 14 or its surroundings may be any of the following: voltage, current value, resistance value including the edge ring 14, etc., at any point on the edge ring 14 or its surroundings. Another function or table is predetermined to define the relationship between specific parameters and the wear of the edge ring 14. To estimate the wear of the edge ring 14, the etching apparatus 1 is operated under measurement conditions for estimating wear, namely, the first high-frequency power HF, the second high-frequency power LF1, the third high-frequency power LF2, the pressure in the processing space S, and the flow rate of the processing gas supplied to the processing space S, before the actual etching is performed or during maintenance of the etching apparatus 1. The specific parameters are then obtained, and the wear of the edge ring 14 is determined by inputting these specific parameters into the other function, or by referring to the table using these specific parameters. 【0096】 In the etching apparatus 1, during etching, that is, during the period when one or more of the first to third high-frequency powers HF, LF1, and LF2 are supplied, a DC voltage is applied to the edge ring 14 from the DC power supply 60. This controls the shape of the edge ring 14 and the sheath above the edge region of the wafer W, reducing the inclination of the ion incidence direction to the edge region of the wafer W and controlling the tilt angle. As a result, recesses substantially parallel to the thickness direction of the wafer W are formed over the entire area of ​​the wafer W. 【0097】 More specifically, during etching, the self-bias voltage Vdc is measured by a measuring instrument (not shown). A DC voltage is also applied to the edge ring 14 from a DC power supply 60. The value of the DC voltage applied to the edge ring 14 is -(|Vdc|+ΔV), as described above. |Vdc| is the absolute value of the self-bias voltage Vdc measured by the measuring instrument immediately prior to etching, and ΔV is a set value determined by the control unit 100. Thus, the DC voltage applied to the edge ring 14 is determined from the self-bias voltage Vdc measured during etching. Therefore, even if the self-bias voltage Vdc changes, the DC voltage generated by the DC power supply 60 is corrected, and the tilt angle is appropriately corrected. 【0098】 In the etching apparatus 1, when the edge ring 14 is worn out, a DC voltage set by the control unit 100 is applied to the edge ring 14 from the DC power supply 60. This controls the shape of the edge ring 14 and the sheath above the edge region of the wafer W, reducing the inclination of the ion incidence direction to the edge region of the wafer W, and controlling the tilt angle. As a result, as shown in Figure 11, the tilt correction angle can be adjusted to the target angle θ3, making the tilt angle 0 degrees. 【0099】 (3) Adjustment of drive amount The following describes how to adjust the drive amount of the lifting device 80. Figure 12 is an explanatory diagram showing the relationship between the drive amount of the lifting device 80 and the tilt correction angle. In Figure 12, the vertical axis represents the tilt correction angle, and the horizontal axis represents the drive amount of the lifting device 80. As shown in Figure 12, increasing the drive amount of the lifting device 80 increases the tilt correction angle. 【0100】 The control unit 100 sets the drive amount of the lifting device 80 based on the wear amount of the edge ring 14, similar to the setting of the impedance of the second RF filter 63 described above. Then, for example, the drive amount of the lifting device 80 is increased according to the wear amount of the edge ring 14 to raise the edge ring 14. 【0101】 In etching apparatus 1, when the edge ring 14 is worn out, the control unit 100 raises the edge ring 14 based on the drive amount set. This controls the shape of the sheath above the edge region of the wafer W, reducing the inclination of the ion incidence direction to the edge region of the wafer W, and controlling the tilt angle. As a result, as shown in Figure 12, the tilt correction angle can be adjusted to the target angle θ3, making the tilt angle 0 degrees. 【0102】 (4) Adjustment of impedance and DC voltage The following describes how to adjust the impedance of the second RF filter 63 in combination with the DC voltage from the DC power supply 60. Figure 13 is an explanatory diagram showing the relationship between the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the tilt correction angle. In Figure 13, the vertical axis represents the tilt correction angle, and the horizontal axis represents the impedance of the second RF filter 63. 【0103】 As shown in Figure 13, first, the impedance of the second RF filter 63 is adjusted to correct the tilt angle. Next, when the impedance reaches a predetermined value, for example, the upper limit, the DC voltage from the DC power supply 60 is adjusted to adjust the tilt correction angle to the target angle θ3, thereby setting the tilt angle to 0 degrees. In this case, the number of times the impedance and DC voltage are adjusted can be reduced, simplifying the operation of the tilt angle control. 【0104】 Here, the resolution of tilt angle correction by impedance adjustment and the resolution of tilt angle correction by DC voltage adjustment depend on the performance of the second RF filter 63 and the DC power supply 60, respectively. The resolution of tilt angle correction is the amount of tilt angle correction in a single adjustment of impedance or DC voltage. For example, if the resolution of the second RF filter 63 is higher than the resolution of the DC power supply 60, the overall resolution of tilt angle correction can be improved by adjusting the impedance of the second RF filter 63 to correct the tilt angle in this embodiment. 【0105】 As described above, by adjusting the impedance of the second RF filter 63 and the DC voltage from the DC power supply 60, the adjustment range of the tilt angle can be increased. Therefore, the tilt angle can be appropriately controlled, that is, the direction of ion incidence can be appropriately adjusted, and thus etching can be performed uniformly. 【0106】 In the example shown in Figure 13, the tilt correction angle was adjusted to the target angle θ3 by adjusting the impedance and DC voltage once each. However, the number of times these impedance and DC voltage adjustments are performed is not limited to this. For example, as shown in Figure 14, the impedance and DC voltage may be adjusted multiple times each. Even in such cases, the same effects as in this embodiment can be enjoyed. 【0107】 Furthermore, in the examples shown in Figures 13 and 14, the impedance of the second RF filter 63 was adjusted first, followed by the adjustment of the DC voltage from the DC power supply 60. However, this order may be reversed. In this case, first, the DC voltage from the DC power supply 60 is adjusted to correct the tilt angle. If the absolute value of the DC voltage is made too high, a discharge will occur between the wafer W and the edge ring 14. Therefore, there is a limit to the DC voltage that can be applied to the edge ring 14. Next, when the DC voltage reaches a predetermined value, for example, the upper limit, the impedance of the second RF filter 63 is adjusted to adjust the tilt correction angle to the target angle θ3, thereby setting the tilt angle to 0 degrees. Even in this case, the same effects as in this embodiment can be enjoyed. 【0108】 Furthermore, in the above embodiments, the impedance of the second RF filter 63 and the DC voltage from the DC power supply 60 were adjusted individually, but the impedance adjustment and the DC voltage adjustment may be performed simultaneously. 【0109】 (5) Adjustment of impedance and drive amount The following describes how to adjust the impedance of the second RF filter 63 in combination with the drive amount of the lifting device 80. Figure 15 is an explanatory diagram showing the relationship between the impedance of the second RF filter 63, the drive amount of the lifting device 80, and the tilt correction angle. In Figure 15, the vertical axis represents the tilt correction angle, and the horizontal axis represents the impedance of the second RF filter 63. 【0110】 As shown in Figure 15, first, the impedance of the second RF filter 63 is adjusted to correct the tilt angle. Next, when the impedance reaches a predetermined value, for example, the upper limit, the drive amount of the lifting device 80 is adjusted to adjust the tilt correction angle to the target angle θ3, thereby setting the tilt angle to 0 degrees. 【0111】 Note that the impedance and drive amount may be adjusted multiple times. Alternatively, after correcting the tilt angle by adjusting the drive amount, the impedance may be adjusted to adjust the tilt correction angle to the target angle θ3. Or, the impedance and drive amount may be adjusted simultaneously. 【0112】 (6) Adjustment of DC voltage and drive amount This section describes the case where the DC voltage from the DC power supply 60 and the impedance of the second RF filter 63 are combined for adjustment. Figure 16 is an explanatory diagram showing the relationship between the DC voltage from the DC power supply 60, the drive amount of the lifting device 80, and the tilt correction angle. In Figure 16, the vertical axis represents the tilt correction angle, and the horizontal axis represents the DC voltage from the DC power supply 60. 【0113】 As shown in Figure 16, first, the DC voltage from the DC power supply 60 is adjusted to correct the tilt angle. Next, when the DC voltage reaches a predetermined value, for example, the upper limit, the drive amount of the lifting device 80 is adjusted to adjust the tilt correction angle to the target angle θ3, and the tilt angle is set to 0 degrees. 【0114】 The DC voltage and drive amount may be adjusted multiple times. Alternatively, after correcting the tilt angle by adjusting the drive amount, the DC voltage may be adjusted to adjust the tilt correction angle to the target angle θ3. Or, the DC voltage and drive amount may be adjusted simultaneously. 【0115】 (7) Adjustment of impedance, DC voltage and drive amount The following describes how to adjust the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80 in combination. Figure 17 is an explanatory diagram showing the relationship between the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, the drive amount of the lifting device 80, and the tilt correction angle. In Figure 17, the vertical axis represents the tilt correction angle, and the horizontal axis represents the impedance of the second RF filter 63. 【0116】 As shown in Figure 17, first, the impedance of the second RF filter 63 is adjusted to correct the tilt angle. Next, when the impedance reaches a predetermined value, for example, the upper limit, the DC voltage from the DC power supply 60 is adjusted to correct the tilt angle. Furthermore, when the absolute value of the DC voltage reaches a predetermined value, for example, the upper limit, the drive amount of the lifting device 80 is adjusted to adjust the tilt correction angle to the target angle θ3, thereby setting the tilt angle to 0 degrees. 【0117】 Furthermore, when controlling the tilt angle, the combination of adjusting the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80 can be designed arbitrarily. In addition, although the adjustment of the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80 were performed individually, these adjustments may also be performed simultaneously. 【0118】 Furthermore, although the DC power supply 60 was connected to the edge ring 14 via the switching unit 61, the first RF filter 62, and the second RF filter 63, the power supply system that applies the DC voltage to the edge ring 14 is not limited to this. For example, the DC power supply 60 may be electrically connected to the edge ring 14 via the switching unit 61, the second RF filter 63, the first RF filter 62, and the lower electrode 12. In this case, the lower electrode 12 and the edge ring 14 are directly electrically coupled, and the self-bias voltage of the edge ring 14 becomes the same as the self-bias voltage of the lower electrode 12. 【0119】 In this case, if the lower electrode 12 and the edge ring 14 are directly electrically coupled, the sheath thickness on the edge ring 14 cannot be adjusted due to the capacitance below the edge ring 14 determined by the hard structure, for example, and an outer tilt state may occur even without applying a DC voltage. In this regard, in this disclosure, the tilt angle can be controlled by adjusting the DC voltage from the DC power supply 60, the impedance of the second RF filter 63, and the drive amount of the lifting device 80, so that the tilt angle can be adjusted to 0 degrees by changing the tilt angle inward. 【0120】 (Other embodiments) In the embodiments described above, the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80 were adjusted according to the wear of the edge ring 14. However, the timing of the adjustments to the impedance, DC voltage, and drive amount are not limited to these. For example, the drive amount, impedance, and DC voltage may be adjusted according to the processing time of the wafer W. Alternatively, the timing of the adjustments to the drive amount, impedance, and DC voltage may be determined by combining, for example, the processing time of the wafer W with predetermined parameters such as high-frequency power. 【0121】 (Other embodiments) In the above embodiment, the impedance of the second RF filter 63 was made variable, but the impedance of the first RF filter 62 may also be made variable, or the impedances of both RF filters 62 and 63 may be made variable. Also, in the above embodiment, two RF filters 62 and 63 were provided for the DC power supply 60, but the number of RF filters is not limited to this, and for example, there may be one. Also, in the above embodiment, the impedance of the second RF filter 63 was made variable by making some of its elements variable elements, but the configuration for variable impedance is not limited to this. For example, a device that can change the impedance of an RF filter may be connected to an RF filter with variable or fixed impedance. That is, an RF filter with variable impedance may consist of an RF filter and a device connected to the RF filter that can change the impedance of the RF filter. 【0122】 <Configuration of bypass circuit and tilt control knob> As described above, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled using the tilt control knob during etching. Next, the configuration for adjusting the initial tilt angle and controlling the tilt angle will be described. The following (1) to (8) are examples of such configurations. (1) Bypass circuit 70 and second RF filter 63 (2) Bypass circuit 70 and DC power supply 60 (3) Bypass circuit 70 and lifting device 80 (4) Bypass circuit 70, second RF filter 63, and DC power supply 60 (5) Bypass circuit 70, second RF filter 63, and lifting device 80 (6) Bypass circuit 70, DC power supply 60, and lifting device 80 (7) Bypass circuit 70, second RF filter 63, DC power supply 60, and lifting device 80 (8) Bypass circuit 70 and DC pulse power supply 【0123】 (1) Bypass circuit 70 and second RF filter 63 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled by adjusting the impedance of the second RF filter 63 during etching. An example of this configuration may be the configuration shown in Figure 2A. Another example of this configuration is shown in Figure 18, in which the DC power supply 60, switching unit 61, first RF filter 62, and second RF filter 63 are omitted from the configuration shown in Figure 2A. In this case, a first variable passive element 62a and a second variable passive element 63a are provided instead of the first RF filter 62 and the second RF filter 63, respectively. The first variable passive element 62a and the second variable passive element 63a are arranged in this order from the edge ring 14 side. The second variable passive element 63a is connected to ground potential. That is, the second variable passive element 63a is not connected to the first high-frequency power supply 50, the second high-frequency power supply 51, or the third high-frequency power supply 52. Furthermore, one example of this configuration is the one shown in Figures 2 and 18, in which the lifting device 80 is omitted. 【0124】 In one example, at least one of the first variable passive element 62a and the second variable passive element 63a is configured to have a variable impedance. The first variable passive element 62a and the second variable passive element 63a may be, for example, either a coil (inductor) or a capacitor. Furthermore, any variable impedance element, such as a diode, not limited to coils and capacitors, can achieve the same function. The number and position of the first variable passive element 62a and the second variable passive element 63a can also be appropriately designed by a person skilled in the art. Moreover, the elements themselves do not need to be variable; for example, the impedance can be varied by providing multiple elements with fixed impedances and switching combinations of fixed-impedance elements using a switching circuit. The circuit configurations including the first variable passive element 62a and the circuit configurations including the second variable passive element 63a can each be appropriately designed by a person skilled in the art. 【0125】 In this embodiment, the bypass circuit 70 is connected to the path 57 between the matching circuit 53 and the lower electrode 12, and to the path 64 between the second variable passive element 63a and the edge ring 14. However, the arrangement of the bypass circuit 70 is not limited to this. For example, although not shown, the bypass circuit 70 may be connected to the matching circuit 53 and the second variable passive element 63a. 【0126】 (2) Bypass circuit 70 and DC power supply 60 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled by adjusting the DC voltage from the DC power supply 60 during etching. An example of this configuration may be the one shown in Figure 2A. Another example of this configuration may be the one shown in Figure 2A in which the lifting device 80 is omitted. 【0127】 (3) Bypass circuit 70 and lifting device 80 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled by adjusting the drive amount of the lifting device 80 during etching. An example of this configuration may be the configuration shown in Figure 2A. Another example of this configuration is shown in Figure 19, in which the DC power supply 60, switching unit 61, first RF filter 62, and second RF filter 63 are omitted from the configuration shown in Figure 2A. In this case, the bypass circuit 70 is connected to the path 64 connected to the edge ring 14. 【0128】 (4) Bypass circuit 70, second RF filter 63, and DC power supply 60 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled during etching by adjusting the impedance of the second RF filter 63 and the DC voltage from the DC power supply 60. An example of this configuration may be the configuration shown in Figure 2A. Another example of this configuration may be the configuration shown in Figure 2A in which the lifting device 80 is omitted. 【0129】 (5) Bypass circuit 70, second RF filter 63, and lifting device 80 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled during etching by adjusting the impedance of the second RF filter 63 and the drive amount of the lifting device 80. An example of this configuration may be the one shown in Figure 2A. Another example of this configuration may be the one shown in Figure 18. 【0130】 (6) Bypass circuit 70, DC power supply 60, and lifting device 80 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled during etching by adjusting the DC voltage from the DC power supply 60 and the drive amount of the lifting device 80. An example of this configuration may be the one shown in Figure 2A. 【0131】 (7) Bypass circuit 70, second RF filter 63, DC power supply 60, and lifting device 80 In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled during etching by adjusting the impedance of the second RF filter 63, the DC voltage from the DC power supply 60, and the drive amount of the lifting device 80. An example of this configuration may be the one shown in Figure 2A. 【0132】 (8) Bypass circuit 70 and DC pulse power supply In this configuration, the initial tilt angle is adjusted by the bypass circuit 70 in the initial state, and then the tilt angle is controlled during etching by applying a pulsed negative voltage to the edge ring 14. 【0133】 One example of this configuration is shown in Figure 20, in which a pulse power supply 65 is placed in place of the DC power supply 60 in the configuration shown in Figure 2A. The pulse power supply 65 may be configured to apply a pulse voltage itself, or it may be configured to include a DC power supply and a device (pulse generation unit) downstream of the DC power supply that pulses the voltage. In this case, the bypass circuit 70 may be connected to the path 57 between the matching unit 53 and the lower electrode 12, and to the path 66 between the edge ring 14 and the pulse power supply 65. Alternatively, although not shown, the bypass circuit 70 may be connected to the matching unit 53 and the third RF filter 67, which will be described later. Also, although not shown, if the edge ring 14 and the pulse power supply 65 are not connected, the bypass circuit 70 may be directly connected to the edge ring 14. In this case, the lifting device 80 may be omitted. 【0134】 The pulse power supply 65 is a power supply that applies a pulsed negative polarity DC voltage to the edge ring 14. The pulse power supply 65 is coupled to the edge ring 14 in a path 66 between the edge ring 14 and the pulse power supply 65. A third RF filter 67 (corresponding to the second RF filter in this disclosure) is provided in the path 66 to protect the pulse power supply 65. The third RF filter 67 is provided in the matching unit 53. The pulse power supply 65 is also coupled to the lower electrode 12 in a path 68 between the lower electrode 12 and the pulse power supply 65. A fourth RF filter 69 (corresponding to the first RF filter in this disclosure) is provided in the path 68 to protect the pulse power supply 65. The fourth RF filter 69 is provided in the matching unit 53. Note that a matching circuit may be provided instead of the third RF filter 67 and the fourth RF filter 69, or all of these may be provided together. 【0135】 In one example, the third RF filter 67 is configured to have a variable impedance. That is, the third RF filter 67 includes at least one variable passive element, and its impedance is variable. The variable passive element may be, for example, a coil (inductor) or a capacitor. Furthermore, it is not limited to coils and capacitors; any variable impedance element such as a diode can achieve the same function. The number and position of the variable passive elements can also be appropriately designed by a person skilled in the art. Moreover, the element itself does not need to be variable; for example, the impedance can be varied by providing multiple elements with fixed impedances and switching combinations of fixed-impedance elements using a switching circuit. The circuit configuration including this third RF filter 67 and the circuit configuration including the fourth RF filter 69 can each be appropriately designed by a person skilled in the art. 【0136】 In such cases, the tilt angle is controlled by adjusting the pulsed voltage from the pulse power supply 65. For example, increasing the pulsed voltage from the pulse power supply 65 increases the tilt correction angle. This control of the tilt angle using the pulsed DC voltage from the pulse power supply 65 is similar to the control of the tilt angle using the DC voltage from the DC power supply 60 described above. 【0137】 Furthermore, if the pulse power supply 65 consists of a DC power supply and a pulse generation unit and functions as a power supply for plasma generation, the first matching circuit 54 may be omitted. In this case, the pulse power supply 65 may function as a power supply for plasma generation on its own. 【0138】 Another example of this configuration is shown in Figure 21A, in which a first pulse power supply 90 and a second pulse power supply 91 are arranged in the configuration shown in Figure 2A. The first pulse power supply 90 and the second pulse power supply 91 may each be configured to apply a pulse voltage themselves, or they may be configured to include a DC power supply and a device (pulse generation unit) downstream of this DC power supply that pulses the voltage. 【0139】 The first pulse power supply 90 is provided in place of the first high-frequency power supply 50 and applies a pulsed negative polarity first DC voltage (hereinafter referred to as the "first pulse voltage") to the lower electrode 12 as source power for plasma generation. The first pulse voltage may have a first frequency in the range of 27 MHz to 100 MHz, and in one example it is 40 MHz. The first pulse power supply 90 is coupled to the lower electrode 12 via a path 92. A fifth RF filter 93 for protecting the first pulse power supply 90 is provided in the path 92. Note that the first high-frequency power supply 50 does not necessarily have to be electrically coupled to the lower electrode 12, but may be coupled to the upper electrode, which is the shower head 20. 【0140】 The second pulse power supply 91 is provided in place of the second high-frequency power supply 51 and the third high-frequency power supply 52, and applies a pulsed negative polarity second DC voltage (hereinafter referred to as the "second pulse voltage") to the lower electrode 12 as bias power for drawing ions into the wafer W. The second pulse voltage may have a second frequency in the range of 100 kHz to 15 MHz, and in one example it is 400 kHz. The second pulse power supply 91 is coupled to the lower electrode 12 via a path 92. A sixth RF filter 94 (corresponding to the fourth RF filter in this disclosure) is provided in the path 92 to protect the second pulse power supply 91. 【0141】 A second pulse power supply 91 is provided in place of the DC power supply 60 and applies a negative polarity DC voltage to the edge ring 14. The second pulse power supply 91 is coupled to the edge ring 14 via a path 95. The path 95 includes a variable passive element 96 and a seventh RF filter 97 (corresponding to the fifth RF filter in this disclosure) for protecting the second pulse power supply 91. The variable passive element 96 and the seventh RF filter 97 are arranged in this order from the edge ring 14 side. 【0142】 In one example, the variable passive element 96 is configured to have a variable impedance. The variable passive element 96 may be, for example, either a coil (inductor) or a capacitor. Furthermore, it is not limited to coils and capacitors; any variable impedance element such as a diode can achieve the same function. The number and position of the variable passive elements 96 can also be appropriately designed by a person skilled in the art. Moreover, the element itself does not need to be variable; for example, the impedance can be varied by providing multiple elements with fixed impedances and switching the combination of fixed-impedance elements using a switching circuit. The circuit configuration including the variable passive element 96 can also be appropriately designed by a person skilled in the art. 【0143】 The bypass circuit 70 may be connected between the path 92 between the first pulse power supply 90 and the second pulse power supply 91 and the lower electrode 12, and between the path 95 between the second pulse power supply 91 and the edge ring 14. 【0144】 In such cases, the tilt angle is controlled by adjusting the pulsed voltage from the second pulsed power supply 91. For example, increasing the pulsed voltage from the second pulsed power supply 91 increases the tilt correction angle. This control of the tilt angle using the pulsed DC voltage from the second pulsed power supply 91 is similar to the control of the tilt angle using the DC voltage from the DC power supply 60 described above. 【0145】 As shown in Figure 21B, the second pulse power supply 91 does not necessarily have to be connected to the edge ring 14. In this case, the bypass circuit 70 is connected to the path 95 that is connected to the edge ring 14. 【0146】 <Other Embodiments> As described above, the frequency of the second high-frequency power (bias RF power) LF1 supplied from the second high-frequency power supply 51 is 400kHz to 13.56MHz, but 5MHz or less is more preferable. When etching, if high aspect ratio etching is performed on the wafer W, high ion energy is required to achieve a vertical shape of the pattern after etching. As a result of diligent research by the inventors, it was found that by setting the frequency of the second high-frequency power LF1 to 5MHz or less, the ions' ability to follow changes in the high-frequency electric field is improved, and the controllability of the ion energy is enhanced. 【0147】 On the other hand, if the frequency of the second high-frequency power LF1 is set to a low frequency of 5 MHz or less, the effect of making the impedance of the second RF filter 63 variable may decrease. In other words, the controllability of the tilt angle by adjusting the impedance of the second RF filter 63 may decrease. For example, in Figures 2A and 2B, if the electrical connection between the edge ring 14 and the second RF filter 63 is non-contact or capacitively coupled, the tilt angle cannot be properly controlled even if the impedance of the second RF filter 63 is adjusted. Therefore, in this embodiment, the edge ring 14 and the second RF filter 63 are electrically directly connected. 【0148】 The edge ring 14 and the second RF filter 63 are electrically directly connected via a connector. The edge ring 14 and the connector are in contact, and a direct current flows through the connector. An example of the structure of the connector (hereinafter sometimes referred to as the "contact structure") will be described below. 【0149】 As shown in Figure 22, the connection portion 200 has a conductor structure 201 and a conductor member 202. The conductor structure 201 connects the edge ring 14 and the second RF filter 63 via the conductor member 202. Specifically, one end of the conductor structure 201 is connected to the second RF filter 63, and the other end is exposed on the upper surface of the lower electrode 12 and in contact with the conductor member 202. 【0150】 The conductor member 202 is provided, for example, in the space formed between the lower electrode 12 and the edge ring 14 on the side of the electrostatic chuck 13. The conductor member 202 is in contact with the conductor structure 201 and the lower surface of the edge ring 14, respectively. The conductor member 202 is made of a conductor such as metal. The configuration of the conductor member 202 is not particularly limited, but examples are shown in Figures 23A to 23F. Figures 23A to 23C show an example in which an elastic material is used as the conductor member 202. 【0151】 As shown in Figure 23A, a leaf spring biased in the vertical direction may be used for the conductor member 202. As shown in Figure 23B, a coil spring that is wound helically and extends horizontally may be used for the conductor member 202. As shown in Figure 23C, a spring that is wound helically and extends vertically may be used for the conductor member 202. These conductor members 202 are elastic bodies, and an elastic force acts on them in the vertical direction. Due to this elastic force, the conductor member 202 adheres tightly to the conductor structure 201 and the lower surface of the edge ring 14 with a desired contact pressure, and the conductor structure 201 and the edge ring 14 are electrically connected. 【0152】 As shown in Figure 23D, the conductor member 202 may be a pin that moves up and down by a lifting mechanism (not shown). In this case, as the conductor member 202 rises, it comes into close contact with the conductor structure 201 and the lower surface of the edge ring 14, respectively. By adjusting the pressure acting on the conductor member 202 when it moves up and down, the conductor member 202 can come into close contact with the conductor structure 201 and the lower surface of the edge ring 14 with a desired contact pressure. 【0153】 As shown in Figure 23E, the conductor member 202 may be a wire that connects the conductor structure 201 and the edge ring 14. One end of the wire is joined to the conductor structure 201, and the other end is joined to the lower surface of the edge ring 14. This joining of the wire only needs to be ohmic contact with the lower surface of the conductor structure 201 or the edge ring 14; for example, the wire can be welded or crimped. When a wire is used for the conductor member 202 in this way, the conductor member 202 contacts the lower surfaces of both the conductor structure 201 and the edge ring 14, thereby electrically connecting the conductor structure 201 and the edge ring 14. 【0154】 In any of the conductive members 202 shown in Figures 23A to 23E, the edge ring 14 and the second RF filter 63 can be electrically directly connected via the connection part 200, as shown in Figure 22. Therefore, the frequency of the second high-frequency power LF1 can be set to a low frequency of 5 MHz or less, improving the controllability of the ion energy. 【0155】 Furthermore, when controlling the tilt angle by adjusting the drive amount of the lifting device 80, the amount of drive to be adjusted can be kept small due to the presence of the connection part 200. As a result, discharge between the wafer W and the edge ring 14 can be suppressed. Moreover, as described above, by adjusting the drive amount of the lifting device 80 and the impedance of the second RF filter 63, the adjustment range of the tilt angle can be increased, and the tilt angle can be controlled to a desired value. 【0156】 In the embodiments described above, the conductor member 202 is exemplified by the leaf spring shown in Figure 23A, the coil spring shown in Figure 23B, the spring shown in Figure 23C, the pin shown in Figure 23D, and the wire shown in Figure 23E. However, a combination of these may also be used. 【0157】 In the connection portion 200 of the above embodiment, as shown in Figure 23F, a conductive film 203 may be provided between the conductor member 202 and the edge ring 14 of the connection portion 200. For example, a metal film can be used for the conductive film 203. The conductive film 203 is provided on the lower surface of the edge ring 14 at least in the portion that the conductor member 202 contacts. The conductive film 203 may be provided over the entire lower surface of the edge ring 14, or multiple conductive films 203 may be provided in a shape that is close to annular overall. In either case, the conductive film 203 can suppress resistance due to contact with the conductor member 202, and the edge ring 14 and the second RF filter 63 can be properly connected. 【0158】 In the above embodiments, the connection portion 200 preferably has a configuration that protects the conductor member 202 from plasma when the edge ring 14 is raised by the lifting device 80. Figures 24A to 24G each show an example of plasma protection for the conductor member 202. 【0159】 As shown in Figure 24A, projections 14a and 14b may be provided on the lower surface of the edge ring 14, projecting downward from the lower surface. In the illustrated example, projection 14a is provided on the radially inward side of the conductor member 202, and projection 14b is provided on the radially outward side of the conductor member 202. That is, the conductor member 202 is provided in the recess formed by projections 14a and 14b. In this case, projections 14a and 14b can suppress plasma from wrapping around the conductor member 202, thereby protecting the conductor member 202. 【0160】 In the example shown in Figure 24A, protrusions 14a and 14b are provided on the lower surface of the edge ring 14. However, the shape for suppressing plasma leakage is not limited to this and should be determined according to the etching apparatus 1. Furthermore, the shape of the edge ring 14 should be determined so that it can be properly raised and lowered by the lifting device 80. 【0161】 As shown in Figure 24B, an insulating member 210 may be provided inside the conductor member 202 on the upper surface of the lower electrode 12. The insulating member 210 is provided separately from the lower electrode 12 and, for example, has an annular shape. In this case, the insulating member 210 can suppress plasma from wrapping around the conductor member 202 and protect the conductor member 202. 【0162】 As shown in Figure 24C, both the projection 14a of the edge ring 14 shown in Figure 24A and the insulating member 210 shown in Figure 24B may be provided. In this case, the projection 14a and the insulating member 210 can further suppress plasma leakage and protect the conductor member 202. 【0163】 As shown in Figure 24D, both the projections 14a and 14b of the edge ring 14 shown in Figure 24A and the insulating member 210 shown in Figure 24B may be provided. The conductor member 202 is in contact with the projection 14b. The insulating member 210 is provided between the projections 14a and 14b. In this case, a labyrinth structure is formed by the projections 14a and 14b and the insulating member 210, which can further suppress plasma leakage and protect the conductor member 202. 【0164】 As shown in Figure 24E, the edge ring 14 may be divided into an upper edge ring 140 and a lower edge ring 141. The upper edge ring 140 is configured to be able to move up and down by a lifting device 80. The lower edge ring 141 does not move up and down. The conductor member 202 is provided in contact with the lower surface of the upper edge ring 140 and the upper surface of the lower edge ring 141. The conductor structure 201 is connected to the lower edge ring 141. In this case, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the conductor member 202, the lower edge ring 141, and the conductor structure 201. 【0165】 On the outermost part of the lower surface of the upper edge ring 140, a projection 140a is provided that protrudes downward from the lower surface. On the innermost part of the upper surface of the lower edge ring 141, a projection 141a is provided that protrudes upward from the upper surface. In this case, the projections 140a and 141a can suppress the plasma from wrapping around the conductor member 202, thereby protecting the conductor member 202. 【0166】 Figure 24F is a modified version of Figure 24E. In the example shown in Figure 24E, the conductor structure 201 was connected to the lower edge ring 141, but in the example shown in Figure 24F, one end of the conductor structure 201 is exposed on the upper surface of the lower electrode 12 and contacts the conductor member 220. The conductor member 220 is provided in the space formed between the lower surface of the lower edge ring 141 and the upper surface of the lower electrode 12, radially outward from the electrostatic chuck 13. That is, the conductor member 220 contacts the lower surface of the lower edge ring 141 and the conductor structure 201. In this case, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the conductor member 202, the lower edge ring 141, the conductor member 220, and the conductor structure 201. In this example as well, the protrusions 140a and 141a can suppress plasma from wrapping around to the conductor member 202, thereby protecting the conductor member 202. 【0167】 Figure 24G is a modified example of Figure 24E. In the example shown in Figure 24E, the conductor member 202 was provided on the upper surface of the lower edge ring 141, but in the example shown in Figure 24G, the conductor member 202 is provided on the upper surface of the lower electrode 12. The conductor member 202 is in contact with the lower surface of the upper edge ring 140 and the conductor structure 201. One end of the conductor structure 201 is exposed on the upper surface of the electrostatic chuck 13 and is in contact with the conductor member 202. In this case, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the conductor member 202 and the conductor structure 201. In this example as well, the protrusions 140a and 141a can suppress plasma from wrapping around the conductor member 202, thereby protecting the conductor member 202. 【0168】 In addition, in the above embodiments, the configurations shown in Figures 24A to 24G may be used in combination. Furthermore, in the connection portion 200, a plasma-resistant coating may be applied to the portion of the conductor member 202 other than the portion that contacts the edge ring 14 on its surface. In this case, the conductor member 202 can be protected from plasma. 【0169】 Next, the arrangement of the conductor members 202 in a plan view will be described. Figures 25A to 25C each show an example of the planar arrangement of the conductor members 202. As shown in Figures 25A and 25B, the connection portion 200 may be provided with multiple conductor members 202, and the multiple conductor members 202 may be provided at equal intervals on a concentric circle with the edge ring 14. In the example in Figure 25A, conductor members 202 are provided at 8 locations, and in Figure 25B, conductor members 202 are provided at 24 locations. Also, as shown in Figure 25C, the conductor members 202 may be provided in a ring shape on a concentric circle with the edge ring 14. 【0170】 From the viewpoint of uniform etching and uniform sheath shape (process uniformity), it is preferable to arrange the conductor members 202 in an annular shape around the edge ring 14, as shown in Figure 25C, and to ensure uniform contact with the edge ring 14 along the circumference. Also from the viewpoint of process uniformity, even when multiple conductor members 202 are provided, as shown in Figures 25A and 25B, it is preferable to arrange these multiple conductor members 202 at equal intervals in the circumferential direction of the edge ring 14 and to provide point-symmetric contact points with the edge ring 14. Furthermore, compared to the example in Figure 25A, it is better to increase the number of conductor members 202 as in the example in Figure 25B and make them closer to an annular shape as shown in Figure 25C. The number of conductor members 202 is not particularly limited, but to ensure symmetry, three or more are preferable, for example, 3 to 36. 【0171】 However, due to the device configuration, it may be difficult to make the conductor members 202 ring-shaped or to increase the number of conductor members 202 in order to avoid interference with other components. Therefore, the planar arrangement of the conductor members 202 may be set as appropriate, taking into consideration the conditions for process uniformity and the constraints of the device configuration. 【0172】 Next, the relationship between the connection section 200 and the first RF filter 62 and the second RF filter 63 will be explained. Figures 26A to 26C schematically show an example of the configuration of the connection section 200, the first RF filter 62, and the second RF filter 63, respectively. 【0173】 As shown in Figure 26A, if, for example, one first RF filter 62 and one second RF filter 63 are provided for each of the eight conductor members 202, the connection section 200 may further include a relay member 230. Although Figure 26A illustrates the case where a relay member 230 is provided in the connection section 200 shown in Figure 25A, a relay member 230 can also be provided in the connection section 200 shown in either Figure 25B or Figure 25C. Furthermore, multiple relay members 230 may be provided. 【0174】 The relay member 230 is provided in a ring shape concentrically with the edge ring 14 in the conductor structure 201 between the conductor member 202 and the second RF filter 63. The relay member 230 is connected to the conductor member 202 by a conductor structure 201a. That is, eight conductor structures 201a extend radially from the relay member 230 in a plan view and are connected to each of the eight conductor members 202. The relay member 230 is also connected to the second RF filter 63 via the first RF filter 62 by a conductor structure 201b. 【0175】 In such cases, even if, for example, the second RF filter 63 is not positioned at the center of the edge ring 14, the electrical characteristics (arbitrary voltage and current values) of the relay member 230 can be made uniform along the circumference, and furthermore, the electrical characteristics of each of the eight conductor members 202 can be made uniform. As a result, etching can be performed uniformly, and the shape of the sheath can be made uniform. 【0176】 As shown in Figure 26B, for example, multiple first RF filters 62, for example eight, may be provided for eight conductive members 202, and one second RF filter 63 may be provided. In this way, the number of first RF filters 62 can be appropriately set in relation to the number of conductive members 202. In addition, a relay member 230 may also be provided in the example of Figure 26B. 【0177】 As shown in Figure 26C, for example, for eight conductive members 202, multiple first RF filters 62, for example eight, and multiple second RF filters 63, for example eight, may be provided. In this way, the number of second RF filters 63 with variable impedance can be appropriately set in relation to the number of conductive members 202. In the example of Figure 26C, a relay member 230 may also be provided. 【0178】 Furthermore, by providing multiple second RF filters 63 with variable impedance, it becomes possible to individually and independently control the electrical characteristics of multiple conductor members 202. As a result, the electrical characteristics of each of the multiple conductor members 202 can be made uniform, thereby improving the uniformity of the process. 【0179】 Next, we will describe examples of contact structures for the edge ring 14 other than those shown in Figures 22 and 23A to 23F. Figures 27A to 27D and 28A to 28D show other examples of connection configurations, respectively. 【0180】 Figures 27A to 27D show examples in which the lifting pin 300 of the lifting device 80 is made of an insulator and a connecting part 310 is provided inside the lifting pin 300. 【0181】 As shown in Figure 27A, the lifting device 80 may have a lifting pin 300 instead of the lifting pin 81 in the above embodiment. The lifting pin 300 extends vertically from the lower surface of the edge ring 14 and is provided penetrating the electrostatic chuck 13, the lower electrode 12, the support member 17, and the bottom of the chamber 10. The space between the lifting pin 300 and the chamber 10 is sealed to seal the inside of the chamber 10. The lifting pin 300 is made of an insulator. The lifting pin 300 is also configured to be able to move up and down by a drive source 82 provided outside the chamber 10. 【0182】 A connecting portion 310 is provided inside the lifting pin 300. The connecting portion 310 directly connects the edge ring 14 and the lifting pin 300, and connects the edge ring 14 to the second RF filter 63. Specifically, one end of the connecting portion 310 is connected to the second RF filter 63, and the other end is exposed on the upper surface of the lifting pin 300 and in contact with the lower surface of the edge ring 14. 【0183】 As shown in Figures 27B and 27C, the connection portion 310 provided inside the lifting pin 300 may have a conductor structure 311 and a conductor member 312. The conductor structure 311 connects the edge ring 14 and the second RF filter 63 via the conductor member 312. Specifically, one end of the conductor structure 311 is connected to the second RF filter 63, and the other end is exposed in the upper space inside the lifting pin 300 and in contact with the conductor member 312. 【0184】 The conductor member 312 is provided in the upper space inside the lifting pin 300. The conductor member 312 contacts the conductor structure 311 and the lower surface of the edge ring 14, respectively. The conductor member 312 is made of a conductor such as metal. The configuration of the conductor member 312 is not particularly limited, but for example, as shown in Figure 27B, an elastic leaf spring biased in the vertical direction may be used, or as shown in Figure 27C, a wire connecting the conductor structure 311 and the edge ring 14 may be used. Alternatively, the conductor member 312 may be a coil spring as shown in Figure 23B, a spring as shown in Figure 23C, a pin as shown in Figure 23D, etc. In such cases, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the conductor member 312 and the conductor structure 311. 【0185】 As shown in Figure 27D, the lifting pin 300 has a hollow cylindrical shape with open top and bottom surfaces, and the connecting portion 310 provided inside the lifting pin 300 may have a conductor structure (first conductor structure) 311 and a conductor member 312, as well as another conductor structure (second conductor structure) 313. The conductor structure 313 is provided on the inner surface of the lifting pin 300. The conductor structure 313 may be, for example, a metal film or a metal cylinder. 【0186】 Conductor structure 311 is connected to the lower end of conductor structure 313. Conductor member 312 is connected to the upper end of conductor structure 313. In this case, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via conductor member 312, conductor structure 313, and conductor structure 311. 【0187】 In any of the connection parts 310 shown in Figures 27A to 27D, the edge ring 14 and the second RF filter 63 can be electrically connected directly via the connection part 310. Therefore, the frequency of the second high-frequency power LF1 can be set to a low frequency of 5 MHz or less, and the controllability of the ion energy can be improved. 【0188】 Furthermore, since the connection portion 310 in the above embodiment is provided inside the lifting pin 300 which is made of an insulator, it does not need to have a configuration that protects it from plasma. 【0189】 Figures 28A to 28D show examples in which the lifting pins 400 of the lifting device 80 are made of a conductive material, and the lifting pins 400 themselves constitute a connection part. 【0190】 As shown in Figure 28A, the lifting device 80 may have a lifting pin 400 instead of the lifting pins 81 and 300 of the above embodiment. The lifting pin 400 extends vertically from the lower surface of the edge ring 14 and is provided penetrating the electrostatic chuck 13, the lower electrode 12, the support member 17, and the bottom of the chamber 10. The space between the lifting pin 400 and the chamber 10 is sealed to seal the inside of the chamber 10. The lifting pin 400 is made of a conductor. The lifting pin 400 is also configured to be able to move up and down by a drive source 82 provided outside the chamber 10. 【0191】 A conductor structure 410 is connected to the lower end of the lifting pin 400. The conductor structure 410 is connected to the second RF filter 63. In this case, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the lifting pin 400 and the conductor structure 410. 【0192】 Preferably, the lifting pin 400 has a configuration that protects it from plasma when the edge ring 14 is raised by the lifting device 80. Figures 28B to 28C show examples of plasma protection measures for the lifting pin 400, respectively. 【0193】 As shown in Figure 28B, an insulating member 210, as shown in Figure 24B, may be provided on the upper surface of the lower electrode 12, inside the lifting pin 400. In this case, the insulating member 210 can prevent plasma from wrapping around to the lifting pin 400, thereby protecting the lifting pin 400. Note that the configuration for suppressing plasma wrapping is not limited to this, and any of the configurations shown in Figures 24A, 24C to 24G may be applied. 【0194】 As shown in Figure 28C, a plasma-resistant insulating member 401 may be provided on the outer surface of the lifting pin 400. The insulating member 401 may be, for example, a film of an insulator or a cylinder made of an insulator. In this case, the insulating member 401 can protect the lifting pin 400 from plasma. In addition, the insulating member 401 shown in Figure 28C may be further provided in the configuration of Figure 28B. 【0195】 In all of the cases shown in Figures 28A to 28C, the edge ring 14 and the second RF filter 63 can be electrically connected directly via the lifting pin 400. Therefore, the frequency of the second high-frequency power LF1 can be set to a low frequency of 5 MHz or less, improving the controllability of the ion energy. 【0196】 In Figures 28A to 28C, the lifting pin 400 itself constitutes the connection part, but as shown in Figure 28D, an additional connection part 420 may be provided inside the lifting pin 400. The connection part 420 may have a conductor structure 421 and a conductor member 422. The conductor structure 421 connects the edge ring 14 and the second RF filter 63 via the conductor member 422. Specifically, one end of the conductor structure 421 is connected to the second RF filter 63, and the other end is exposed in the upper space inside the lifting pin 400 and in contact with the conductor member 422. The conductor structure 410 is included in the conductor structure 421. 【0197】 The conductor member 422 is provided in the upper space inside the lifting pin 400. The conductor member 422 contacts the conductor structure 421 and the lower surface of the edge ring 14, respectively. The conductor member 422 is made of a conductor such as metal. The configuration of the conductor member 312 is not particularly limited, but for example, a vertically biased leaf spring as shown in Figure 23A may be used. Alternatively, a coil spring as shown in Figure 23B, a spring as shown in Figure 23C, a pin as shown in Figure 23D, a wire as shown in Figure 23E, etc., may be used. In such cases, the upper edge ring 140 and the second RF filter 63 are electrically directly connected via the conductor member 312 and the conductor structure 311, in addition to the lifting pin 400. Furthermore, since resistance due to contact between the lifting pin 400 and the conductor member 312 can be suppressed, the edge ring 14 and the second RF filter 63 can be connected more appropriately. 【0198】 <Other Embodiments> Although the etching apparatus 1 in the above embodiments was a capacitively coupled etching apparatus, the etching apparatus to which this disclosure applies is not limited to this. For example, the etching apparatus may be an inductively coupled etching apparatus. 【0199】 The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. 【0200】 Embodiments of this disclosure further include the following embodiments: 【0201】 (Note A1) An apparatus for etching a substrate, Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, An RF filter connected to the edge ring, with adjustable impedance, A bypass circuit connected to the matching circuit or the path between the matching circuit and the electrode, and to the RF filter or the path between the RF filter and the edge ring, An etching apparatus equipped with the following features. 【0202】 (Appendix A2) The system further comprises a DC power supply that applies a negative DC voltage to the edge ring via the RF filter, The etching apparatus described in Appendix A1, which is connected to the matching circuit or the path between the matching circuit and the electrode, and to the DC power supply or the path between the DC power supply and the edge ring. 【0203】 (Note A3) An apparatus for etching a substrate, Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, A DC power supply that applies a negative polarity DC voltage to the edge ring, A bypass circuit connected to the matching circuit or the path between the matching circuit and the electrode, and to the DC power supply or the path between the DC power supply and the edge ring, An etching apparatus equipped with the following features. 【0204】 (Note A4) The etching apparatus according to any one of the appendices A1 to A3, further comprising a lifting device for raising and lowering the edge ring. 【0205】 (Note A5) An apparatus for etching a substrate, Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, A lifting device for raising and lowering the edge ring, The matching circuit or the path between the matching circuit and the electrode, and the bypass circuit connected to the edge ring, An etching apparatus equipped with the following features. 【0206】 (Note A6) The etching apparatus according to any one of the appendices A1 to A5, wherein the bypass circuit controls the amount of power supplied to the edge ring to adjust the initial tilt angle in the edge region of the substrate placed on the electrostatic chuck. 【0207】 (Note A7) Multiple frequencies of high-frequency power are supplied from the aforementioned high-frequency power supply. An etching apparatus according to any one of the appendices A1 to A6, wherein the tilt angle in the edge region of the substrate placed on the electrostatic chuck is controlled with respect to high-frequency power of two or more frequencies among the multiple high-frequency powers. 【0208】 (Note A8) Multiple bypass circuits are provided in the etching apparatus as described in Appendix A7. 【0209】 (Note A9) A method for etching a substrate using an etching apparatus, The etching apparatus is Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, An RF filter connected to the edge ring, with adjustable impedance, A bypass circuit connected to the matching circuit or the path between the matching circuit and the electrode, and to the RF filter or the path between the RF filter and the edge ring, Equipped with, The method is an etching method that includes the step of controlling the amount of power supplied to the edge ring by the bypass circuit to adjust the initial tilt angle before etching in the edge region of the substrate placed on the electrostatic chuck. 【0210】 (Note A10) A method for etching a substrate using an etching apparatus, The etching apparatus is Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, A DC power supply that applies a negative polarity DC voltage to the edge ring, A bypass circuit connected to the matching circuit or the path between the matching circuit and the electrode, and the DC power supply or the path between the DC power supply and the edge ring, Equipped with, The method is an etching method that includes the step of controlling the amount of power supplied to the edge ring by the bypass circuit to adjust the initial tilt angle before etching in the edge region of the substrate placed on the electrostatic chuck. 【0211】 (Note A11) A method for etching a substrate using an etching apparatus, The etching apparatus is Chamber and, A substrate support provided inside the chamber, the substrate support having electrodes, an electrostatic chuck, and a conductive edge ring arranged to surround the substrate placed on the electrostatic chuck, A high-frequency power supply for supplying high-frequency power to the aforementioned electrode, At least one matching circuit connected to the aforementioned high-frequency power supply, A lifting device for raising and lowering the edge ring, The matching circuit or the path between the matching circuit and the electrode, and the bypass circuit connected to the edge ring, Equipped with, The method is an etching method that includes the step of controlling the amount of power supplied to the edge ring by the bypass circuit to adjust the initial tilt angle before etching in the edge region of the substrate placed on the electrostatic chuck. 【0212】 (Note B1) Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more powers with different frequencies, wherein the power supply unit includes a source power supply configured to supply source power for generating plasma from the gas in the chamber to the upper electrode or the lower electrode, and at least one bias power supply configured to supply one or two or more bias powers with different frequencies to the lower electrode. At least one variable passive element electrically connected to the edge ring. At least one bypass circuit configured to electrically connect the power supply unit and the edge ring and supply at least a part of at least one power selected from the group consisting of the source power and at least one of the bias powers to the edge ring. A plasma processing apparatus comprising the above. 【0213】 (Appendix B2) The plasma processing apparatus according to Appendix B1, wherein the at least one bypass circuit is configured to supply at least a part of the at least one power selected according to the frequency to the edge ring. 【0214】 (Appendix B3) The plasma processing apparatus according to Appendix B2, wherein the at least one bypass circuit is configured to include a combination of a bypass circuit provided independently for each frequency and a bypass circuit provided in common for a plurality of frequencies. 【0215】 (Appendix B4) The plasma processing apparatus according to any one of Appendices B1 to B3, wherein the at least one bypass circuit is configured to control the magnitude of the at least one power supplied to the edge ring. 【0216】 (Appendix B5) The source power supply is configured to supply source RF power as the source power. The at least one bias power supply is configured to apply, as the bias power, at least one bias RF power having different frequencies or at least one negative-polarity pulsed voltage having different frequencies, and is the plasma processing apparatus according to any one of Appendices B1 to B4. 【0217】 (Appendix B6) The plasma processing apparatus according to Appendix B5 further includes a matcher including a first matching circuit and at least one second matching circuit. The at least one bias power supply is configured to supply at least one bias RF power having different frequencies as the bias power. The source power supply is connected to the upper electrode or the lower electrode through the first matching circuit. The at least one bias power supply is connected to the lower electrode through the at least one second matching circuit, and is the plasma processing apparatus according to Appendix B5. 【0218】 (Appendix B7) The bypass circuit is arranged in a first path connecting a path between the matcher or between the matcher and the upper electrode or the lower electrode and a path between the variable passive element or between the variable passive element and the edge ring, and is the plasma processing apparatus according to Appendix B6. 【0219】 (Appendix B8) The at least one bias power supply is configured to apply at least one negative-polarity pulsed voltage having different frequencies as the bias power. The at least one bias power supply is respectively connected to the lower electrode through at least one first RF filter, and is the plasma processing apparatus according to Appendix B5. 【0220】 (Appendix B9) The at least one bias power supply is connected to the edge ring through a second RF filter, and is the plasma processing apparatus according to Appendix B8. 【0221】 (Appendix B10) The plasma processing apparatus according to Appendix B9, wherein the bypass circuit is located in a second path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the second RF filter or the path between the second RF filter and the edge ring. 【0222】 (Note B11) The plasma processing apparatus according to Appendix B10, wherein the second RF filter includes at least one variable passive element. 【0223】 (Note B12) The plasma processing apparatus according to any one of the appendices B1 to B4, wherein the power supply unit is a DC power supply configured to apply a negative polarity DC voltage to the edge ring, and further comprises a DC power supply connected to the edge ring via at least one third RF filter. 【0224】 (Note B13) The plasma processing apparatus according to Appendix B12, wherein the bypass circuit is located in a third path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the DC power supply or the path between the DC power supply and the edge ring. 【0225】 (Note B14) The plasma processing apparatus according to Appendix B13, wherein the third RF filter includes at least one variable passive element. 【0226】 (Note B15) The plasma processing apparatus according to any one of the appendices B12 to B14, further comprising a lifting device configured to raise and lower the edge ring. 【0227】 (Note B16) The source power supply is configured to apply a first pulse voltage of negative polarity as the source power, The at least one bias power supply is configured to apply at least one second pulse voltage of negative polarity as the bias power, The plasma processing apparatus according to any one of Supplementary Notes B1 to B4, wherein the frequency of the first pulse voltage is different from the frequency of the second pulse voltage. 【0228】 (Supplementary Note B17) The at least one bias power supply is connected to the lower electrode via a fourth RF filter and connected to the edge ring via a fifth RF filter, The bypass circuit is disposed in a fourth path connecting a path between the fourth RF filter or the fourth RF filter and the lower electrode and a path between the fifth RF filter or the fifth RF filter and the edge ring. The plasma processing apparatus according to Supplementary Note B16. 【0229】 (Supplementary Note B18) A chamber, A substrate support disposed in the chamber, the substrate support including a lower electrode, a substrate support surface for supporting a substrate, and an edge ring disposed so as to surround the substrate supported on the substrate support surface. Substrate support, An upper electrode disposed above the lower electrode, A power supply unit that supplies two or more powers having different frequencies, the power supply unit including a source power supply configured to supply source power for generating plasma from the gas in the chamber to the upper electrode or the lower electrode, and at least one bias power supply configured to supply one or two or more bias powers having different frequencies to the lower electrode. A power supply unit including, A lifting device configured to lift and lower the edge ring, At least one bypass circuit that electrically connects the power supply unit and the edge ring and is configured to supply at least a part of at least one power selected from the group consisting of the source power and at least one of the bias powers to the edge ring. A plasma processing apparatus comprising. 【0230】 (Supplementary Note B19) The plasma processing apparatus according to Appendix B18, wherein the bypass circuit is connected to a fifth path that connects the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode and the path between the edge ring. 【0231】 (Note B20) An etching method using a plasma processing apparatus, The aforementioned plasma processing apparatus is Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; and at least one bias power supply configured to supply one or two or more bias power sources of different frequencies to the lower electrode; At least one variable passive element electrically connected to the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, The etching method described above is (a) A step of placing the substrate on the substrate support surface, (b) A step of generating plasma from the gas in the chamber, (c) A step of etching the substrate with the generated plasma, (d) A step of controlling the amount of power supplied to the edge ring by the bypass circuit to adjust the incidence angle of ions in the plasma to the edge region of the substrate, Etching methods, including [Explanation of symbols] 【0232】 1 Etching apparatus 10 Chambers 11 stages 12 Lower electrode 13 Electrostatic Chuck 14 Edge Rings 21 Electrode plate 50 First high-frequency power supply 51 Second high-frequency power supply 52 Third High-Frequency Power Supply 62 First RF filter 63. Second RF filter 70 Bypass Circuit W wafer

Claims

[Claim 1] Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; at least one bias power supply configured to supply one or more bias power sources of different frequencies to the lower electrode; and a DC power supply configured to apply a negative polarity DC voltage to the edge ring, the DC power supply connected to the edge ring via at least one third RF filter, At least one variable passive element electrically connected to the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, A plasma processing apparatus wherein the bypass circuit is located in a third path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the DC power supply or the path between the DC power supply and the edge ring. [Claim 2] The plasma processing apparatus according to claim 1, wherein the third RF filter includes at least one variable passive element. [Claim 3] The plasma processing apparatus according to claim 1, further comprising a lifting device configured to raise and lower the edge ring. [Claim 4] The plasma apparatus according to claim 1, wherein the at least one bypass circuit is configured to supply a portion of the at least one power selected according to frequency to the edge ring. [Claim 5] The plasma processing apparatus according to claim 4, wherein the at least one bypass circuit is configured to include a combination of a bypass circuit provided independently for each frequency and a bypass circuit provided in common for multiple frequencies. [Claim 6] The plasma apparatus according to claim 1, wherein the at least one bypass circuit is configured to control the magnitude of the at least one power supplied to the edge ring. [Claim 7] The source power supply is configured to supply source RF power as the source power, The plasma processing apparatus according to claim 1, wherein the at least one bias power supply is configured to supply at least one bias RF power with a different frequency as two or more bias powers. [Claim 8] The matching device includes a first matching circuit and at least one second matching circuit, The source power supply is connected to the upper electrode or the lower electrode via the first matching circuit. The plasma processing apparatus according to claim 7, wherein the at least one bias power supply is connected to the lower electrode via the at least one second matching circuit. [Claim 9] Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; and at least one bias power supply configured to supply one or two or more bias power sources of different frequencies to the lower electrode; At least one variable passive element electrically connected to the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, The at least one bypass circuit is configured to supply a portion of the at least one power selected according to frequency to the edge ring. A plasma processing apparatus wherein the at least one bypass circuit is configured to include a combination of a bypass circuit provided independently for each frequency and a bypass circuit provided in common for multiple frequencies. [Claim 10] The source power supply is configured to supply source RF power as the source power, The plasma processing apparatus according to claim 9, wherein the at least one bias power supply is configured to apply, as two or more bias powers, at least one bias RF power with a different frequency, or at least one pulsed voltage of a different negative polarity. [Claim 11] The matching circuit further comprises a first matching circuit and at least one second matching circuit. The at least one bias power supply is configured to supply at least one bias RF power with a different frequency as two or more bias powers. The source power supply is connected to the upper electrode or the lower electrode via the first matching circuit. The plasma processing apparatus according to claim 10, wherein the at least one bias power supply is connected to the lower electrode via the at least one second matching circuit. [Claim 12] The plasma processing apparatus according to claim 11, wherein the bypass circuit is arranged in a first path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the variable passive element or the path between the variable passive element and the edge ring. [Claim 13] The at least one bias power supply is configured to apply at least one negative polarity pulse voltage with different frequencies as two or more bias powers. The plasma processing apparatus according to claim 10, wherein the at least one bias power supply is connected to the lower electrode via at least one first RF filter. [Claim 14] The plasma processing apparatus according to claim 13, wherein the at least one bias power supply is connected to the edge ring via a second RF filter. [Claim 15] The plasma processing apparatus according to claim 14, wherein the bypass circuit is arranged in a second path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the second RF filter or the path between the second RF filter and the edge ring. [Claim 16] The plasma processing apparatus according to claim 15, wherein the second RF filter includes at least one variable passive element. [Claim 17] Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; and at least one bias power supply configured to supply one or two or more bias power sources of different frequencies to the lower electrode; At least one variable passive element electrically connected to the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, The source power supply is configured to apply a first pulse voltage of negative polarity as the source power, The at least one bias power supply is configured to apply at least one second pulse voltage of negative polarity as the bias power, A plasma processing apparatus in which the frequencies of the first pulse voltage and the second pulse voltage are different. [Claim 18] The aforementioned at least one bias power supply is It is connected to the lower electrode via a fourth RF filter and to the edge ring via a fifth RF filter. The plasma processing apparatus according to claim 17, wherein the bypass circuit is arranged in a fourth path connecting the fourth RF filter or the path between the fourth RF filter and the lower electrode and the fifth RF filter or the path between the fifth RF filter and the edge ring. [Claim 19] Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; at least one bias power supply configured to supply one or more bias power sources of different frequencies to the lower electrode; and a DC power supply configured to apply a negative polarity DC voltage to the edge ring, the DC power supply connected to the edge ring via at least one third RF filter, A lifting device configured to raise and lower the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, A plasma processing apparatus wherein the bypass circuit is located in a third path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the DC power supply or the path between the DC power supply and the edge ring. [Claim 20] An etching method using a plasma processing apparatus, The aforementioned plasma processing apparatus is Chamber and, A substrate support disposed within the chamber, the substrate support includes a lower electrode, a substrate support surface for supporting the substrate, and an edge ring disposed to surround the substrate supported by the substrate support surface. An upper electrode positioned above the lower electrode, A power supply unit that supplies two or more power sources of different frequencies, the power supply unit comprising: a source power supply configured to supply source power to the upper electrode or the lower electrode for generating plasma from the gas in the chamber; at least one bias power supply configured to supply one or more bias power sources of different frequencies to the lower electrode; and a DC power supply configured to apply a negative polarity DC voltage to the edge ring, the DC power supply connected to the edge ring via at least one third RF filter, At least one variable passive element electrically connected to the edge ring, At least one bypass circuit is configured to electrically connect the power supply unit and the edge ring and to supply a portion of at least one power selected from the group consisting of the source power and at least one bias power to the edge ring, Equipped with, The bypass circuit is located in a third path connecting the matching circuit or the path between the matching circuit and the upper electrode or the lower electrode, and the DC power supply or the path between the DC power supply and the edge ring. The etching method described above is (a) A step of placing the substrate on the substrate support surface, (b) A step of generating plasma from the gas in the chamber, (c) A step of etching the substrate with the generated plasma, (d) A step of controlling the amount of power supplied to the edge ring by the bypass circuit to adjust the incidence angle of ions in the plasma to the edge region of the substrate, Etching methods, including

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