Plasma processing apparatus and substrate processing method

Abstract

In the plasma processing apparatus of the present invention, the substrate support portion has a base and a dielectric portion. The base includes a base member and electrodes. The base member is formed of a dielectric or an insulator. Electrodes are formed on the top surface of the base member. Electrodes constitute the top surface of the base. The dielectric portion provides a support surface on which the substrate is mounted. The dielectric portion extends from the top surface of the base to the support surface and is formed solely of a dielectric. A bias power supply and a chuck power supply are electrically connected to the electrodes of the base.

Description

[Technical Field]

[0001] The exemplary embodiments of the present invention relate to a plasma processing apparatus and a substrate processing method. [Previous Technology]

[0002] A plasma processing apparatus is used in plasma processing of a substrate. The plasma processing apparatus includes a chamber and a substrate support. The substrate support includes a base and an electrostatic chuck. The base forms a lower electrode. The base is connected to a bias power supply. The electrostatic chuck is disposed on the base. The electrostatic chuck includes an insulating layer and electrodes disposed within the insulating layer. The electrodes of the electrostatic chuck are connected to a DC power supply. Patent Documents 1 and 2 below disclose such a plasma processing apparatus. [Preferred Art Documents] [Patent Documents]

[0003] Patent Document 1: Japanese Patent Application Publication No. 2019-169635; Patent Document 2: Japanese Patent Application Publication No. 2020-205444 [Summary of the Invention]

[0004] [The problem the invention aims to solve]

[0005] This invention provides a technique for efficiently supplying bias power from a bias power supply to a substrate. [Technical Means for Solving the Problem]

[0006] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes: a chamber, a substrate support, a plasma generating section, a bias power supply, and a suction cup power supply. The substrate support is disposed within the chamber. The plasma generating section generates plasma within the chamber. The bias power supply generates bias power for introducing ions from the plasma to the substrate. The suction cup power supply generates a voltage supplied to the substrate support for holding the substrate by electrostatic attraction. The bias power is high-frequency power or a periodically generated voltage pulse. The substrate support has a base and a dielectric portion. The base includes a base member and an electrode. The base member is formed of a dielectric or an insulator. The electrode is formed on the top surface of the base member. The electrode constitutes the top surface of the base. The dielectric portion provides a support surface on which the substrate is mounted. The dielectric portion extends from the top surface of the base to the support surface and is formed solely of a dielectric. The bias power supply and the chuck power supply are electrically connected to the electrodes of the base. [Effects of the Invention]

[0007] By means of an exemplary embodiment, bias power from a bias power supply can be efficiently supplied to the substrate.

Implementation Method

[0009] The following describes the various exemplified implementation forms.

[0010] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes: a chamber, a substrate support, a plasma generating section, a bias power supply, and a suction cup power supply. The substrate support is disposed within the chamber. The plasma generating section generates plasma within the chamber. The bias power supply generates bias power for introducing ions from the plasma to the substrate. The suction cup power supply generates a voltage supplied to the substrate support for holding the substrate by electrostatic attraction. The bias power is high-frequency power or a periodically generated voltage pulse. The substrate support has a base and a dielectric portion. The base includes a base member and an electrode. The base member is formed of a dielectric or an insulator. The electrode is formed on the top surface of the base member. The electrode constitutes the top surface of the base. The dielectric portion provides a support surface on which the substrate is mounted. The dielectric portion extends from the top surface of the base to the support surface and is formed solely of a dielectric. The bias power supply and the chuck power supply are electrically connected to the electrodes of the base.

[0011] Since no electrodes are provided within the dielectric portion in the above embodiment, the thickness of the dielectric portion can be reduced. Therefore, the impedance between the electrodes of the substrate and the substrate is reduced. As a result, bias power is efficiently supplied to the substrate.

[0012] In one exemplary embodiment, the bias power supply may also be electrically connected to the electrodes of the base via a capacitor. The bias power supply is DC isolated from the chuck power supply by means of the capacitor.

[0013] In one exemplary embodiment, the bias power supply and the chuck power supply may also be electrically connected to the electrodes via wiring extending between the top and bottom surfaces of the base member.

[0014] In one exemplary embodiment, the plasma generating unit may also include a high-frequency power supply electrically connected to the electrodes of the base.

[0015] In one exemplary embodiment, the support surface of the dielectric portion may also include a first region on which the substrate is mounted, and a second region on which the edge ring is mounted. In this embodiment, the electrode of the base is a first electrode disposed below the first region. The base may also include a second electrode. The second electrode is disposed below the second region, forming the top surface of the base, and is separated from the first electrode. A bias power supply or another bias power supply and another chuck power supply are electrically connected to the second electrode.

[0016] In one exemplary embodiment, the second electrode may also include two electrodes constituting a bipolar electrode. The other suction cup power source may also include two power sources respectively connected to the two electrodes.

[0017] In one exemplary embodiment, the bias power supply or another bias power supply may also be electrically connected to the second electrode via a capacitor. The bias power supply or another bias power supply is DC isolated from the other chuck power supply by the capacitor.

[0018] In one exemplary embodiment, a bias power supply or another bias power supply and another suction cup power supply may also be electrically connected to the second electrode via wiring extending between the top and bottom surfaces of the base member.

[0019] In another embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes: a chamber, a substrate support, a plasma generating section, a bias power supply, and a suction cup power supply. The substrate support is disposed within the chamber. The plasma generating section generates plasma within the chamber. The bias power supply generates bias power to introduce ions from the plasma into the substrate. The suction cup power supply generates a voltage supplied to the substrate support for holding the substrate by electrostatic attraction. The bias power is high-frequency power or a periodically generated voltage pulse. The substrate support has a base and a dielectric portion. The dielectric portion provides a support surface on which the substrate is mounted and extends from the top surface of the base to the support surface, and is formed solely of dielectric material. The support surface includes a first region on which the substrate is mounted and a second region on which an edge ring is mounted. The base includes a first portion and a second portion. The first portion is formed of a conductive material and is disposed below the first region. Part 2, formed of a conductive material, is located below Part 2 and is separate from Part 1. A bias power supply and a suction cup power supply are electrically connected to Part 1. A bias power supply or another bias power supply and another suction cup power supply are electrically connected to Part 2.

[0020] Since no electrodes are provided within the dielectric portion in the above embodiment, the thickness of the dielectric portion can be reduced. Therefore, the impedance between the first portion of the base and the substrate, and the impedance between the second portion of the base and the edge ring, are reduced. As a result, bias power is efficiently supplied to the substrate and the edge ring.

[0021] In one exemplary embodiment, the second part may also include two parts constituting bipolar electrodes. The other suction cup power source may also include two power sources respectively connected to the two parts.

[0022] In one exemplary embodiment, the bias power supply may also be electrically connected to the first part via a capacitor. The bias power supply is DC isolated from the chuck power supply via the capacitor. Alternatively, the bias power supply or another bias power supply may be electrically connected to the second part via a capacitor. The bias power supply or another bias power supply is DC isolated from the other chuck power supply via the capacitor.

[0023] In one exemplary embodiment, the plasma generating unit may also include a high-frequency power supply electrically connected to the first part of the base.

[0024] In another exemplary embodiment, a substrate processing method is provided, using any of the plasma processing apparatuses described in the above-described embodiments. The substrate processing method includes the step of placing a substrate on a dielectric portion of a substrate support. The substrate processing method further includes the step of generating plasma within a cavity using a plasma generating portion. The substrate processing method further includes the step of securing the substrate to the substrate support by supplying a voltage from a chuck power source. The substrate processing method further includes the step of introducing ions from the plasma onto the substrate by supplying bias power from a bias power source.

[0025] The following will describe in detail the various illustrated embodiments with reference to the drawings. Furthermore, in each drawing, the same or equivalent parts will be marked with the same symbol.

[0026] Figures 1 and 2 are schematic diagrams of an exemplary embodiment of a plasma processing apparatus.

[0027] In one embodiment, a plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generating unit 12. The plasma processing chamber 10 has a plasma processing space. Furthermore, the plasma processing chamber 10 has: at least one gas supply port for supplying at least one processing gas to the plasma processing space; and at least one gas outlet for discharging gas from the plasma processing space. The gas supply port is connected to the gas supply unit 20 described later; the gas outlet is connected to the exhaust system 40 described later. The substrate support 11 is disposed within the plasma processing space and has a substrate support surface for supporting a substrate.

[0028] The plasma generation unit 12 generates plasma from at least one processing gas supplied to the plasma processing space. The plasma formed in the plasma processing space can be: capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR), helicon wave plasma (HWP), or surface wave plasma (SWP), etc. Furthermore, various types of plasma generation units, including AC (Alternating Current) plasma generation units and DC (Direct Current) plasma generation units, can be used. In one embodiment, the AC signal (AC power) used in the AC plasma generation unit has a frequency in the range of 100kHz to 10GHz. Therefore, the AC signal contains RF (Radio Frequency) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 200kHz to 150MHz.

[0029] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various steps described herein. The control unit 2 may be configured to control each component of the plasma processing apparatus 1 to perform the various steps described herein. In one embodiment, the control unit 2 may be partially or wholly included in the plasma processing apparatus 1. The control unit 2 may, for example, include a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a memory unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control actions according to a program stored in the memory unit 2a2. The memory unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 can communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).

[0030] The following describes a configuration example of a capacitively coupled plasma processing apparatus 1, which is one example of a plasma processing apparatus 1. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a plurality of power supplies, and an exhaust system 40. Furthermore, the plasma processing apparatus 1 includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit introduces at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a gas diffuser head 13. The substrate support unit 11 is disposed within the plasma processing chamber 10. The gas diffuser head 13 is disposed above the substrate support unit 11. In one embodiment, the gas diffuser head 13 constitutes at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the gas diffuser head 13, the sidewall 10a of the plasma processing chamber 10, and the substrate support unit 11. The sidewall 10a is grounded. The gas diffusion disk 13 and the substrate support 11 are electrically insulated from the outer shell of the plasma processing chamber 10.

[0031] A substrate support portion 11 supports a substrate W placed thereon. The substrate support portion 11 further supports an edge ring ER placed thereon. The edge ring ER is a ring-shaped component, formed, for example, of a material such as silicon or silicon carbide. The substrate W is disposed on the substrate support portion 11 and within the area surrounded by the edge ring ER. The substrate support portion 11 may also include a temperature control module configured to adjust at least one of the edge ring ER and the substrate W to a target temperature. The temperature control module may also include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows in the flow path. Furthermore, the substrate support portion 11 may also include a heat transfer gas supply portion configured to supply heat transfer gas between the back surface of the substrate W and the substrate support surface.

[0032] The gas diffusion disk 13 introduces at least one type of processing gas from the gas supply unit 20 into the plasma processing space within 10 seconds. The gas diffusion disk 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas inlets 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space within 10 seconds through the plurality of gas inlets 13c. Furthermore, the gas diffusion disk 13 contains a conductive member. The conductive member of the gas diffusion disk 13 functions as an upper electrode. In addition to the gas diffusion disk 13, the gas inlet unit may also contain one or more side gas injectors (SGIs) formed on the sidewall 10a and installed in one or more openings.

[0033] The gas supply unit 20 may also include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one type of process gas from its respective gas source 21, via its respective flow controller 22, to the gas diffuser 13. Each flow controller 22 may also include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may also include at least one flow modulation element for modulating or pulsed flow of the at least one type of process gas.

[0034] A plurality of power sources include: one or more high-frequency power sources constituting the plasma generation section; one or more bias power sources generating bias power for introducing ions into the substrate; and one or more chuck power sources for holding the substrate W and the edge ring ER by electrostatic attraction. These power sources will be described later.

[0035] The exhaust system 40 may be connected to, for example, a gas outlet 10e located at the bottom of the plasma processing chamber 10. The exhaust system 40 may also include a pressure regulating valve and a vacuum pump. The pressure within the plasma processing space 10s is adjusted by means of the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0036] Referring to Figure 3 below. Figure 3 is a diagram illustrating a substrate support portion and a plurality of power sources of an exemplary embodiment of a plasma processing apparatus. The substrate support portion 11A shown in Figure 3 can be used as a substrate support portion 11 of the plasma processing apparatus 1.

[0037] The substrate support portion 11A includes a base 16 and a dielectric portion 18. The base 16 includes a base member 16b and one or more electrodes. The base member 16b is formed of a dielectric or an insulator. The base member 16b is approximately disk-shaped. The base member 16b is formed of ceramic such as aluminum nitride or aluminum oxide.

[0038] One or more electrodes of the base 16 are formed on the top surface of the base member 16b. The one or more electrodes of the base 16 constitute the top surface 16u of the base 16. The one or more electrodes of the base 16 may be a conductive film. In one embodiment, the base 16 may also contain a first electrode 161 and a second electrode 162 as "one or more electrodes". The first electrode 161, including the center of the top surface 16u, is approximately circular. The second electrode 162 is separate from the first electrode 161. The second electrode 162 may also extend in a circumferential direction as if surrounding the first electrode 161. That is, the second electrode 162 may be annular.

[0039] In one embodiment, the second electrode 162 may also include two electrodes 162a and 162b constituting a bipolar electrode. The two electrodes 162a and 162b are separate from each other. The two electrodes 162a and 162b may each be annular. One of the two electrodes 162a and 162b may extend radially outward in a circumferential direction relative to the other. Alternatively, the two electrodes 162a and 162b may each be composed of a plurality of electrodes arranged circumferentially and separately from each other.

[0040] In one embodiment, the base 16 may also include an electrode 163. The electrode 163 may be a conductive film formed on the bottom surface of the base member 16b. In one embodiment, the base 16 may also include a plurality of wirings 165, 166a, and 166b. The plurality of wirings 165, 166a, and 166b extend between the top and bottom surfaces of the base member 16b. One or more wirings 165 connect the first electrode 161 and the electrode 163 to each other. One or more wirings 166a are connected to the electrode 162a. One or more wirings 166b are connected to the electrode 162b. The plurality of wirings 165, 166a, and 166b may each be a through-hole formed in the base member 16b. Alternatively, the plurality of wirings 165, 166a, and 166b may each be a conductor line formed along the surface of the base member 16b. Furthermore, electrode 163 can be a planar electrode, or it can be a wiring that connects the respective power supply points of the first electrode 161, electrode 162a, and electrode 162b to wiring 165, 166a, and 166b, respectively.

[0041] The dielectric portion 18 provides a support surface 18s on which the substrate W is placed. The dielectric portion 18 extends from the top surface 16u of the base 16 to the support surface 18s and is formed solely of dielectric material. The dielectric portion 18 is formed of ceramic such as aluminum nitride or aluminum oxide.

[0042] In one embodiment, the support surface 18s of the dielectric portion 18 may also include a first region 181 and a second region 182. The first region 181, containing the center of the support surface 18s, is approximately circular. The substrate W is placed on the first region 181. The first region 181 extends above the first electrode 161 of the base 16. That is, the first electrode 161 is located below the first region 181.

[0043] The second region 182 extends radially outward in a circumferential direction relative to the first region 181. That is, the second region 182 is annular. An edge ring ER is placed on the second region 182. The second region 182 extends above the second electrode 162 of the base 16. That is, the second electrode 162 (electrodes 162a and 162b) is located below the second region 182.

[0044] In one embodiment, the substrate support portion 11 may further include an insulating portion 11i. The insulating portion 11i covers the edge surface (outer peripheral surface) of the first electrode 161 and the inner edge surface (inner peripheral surface) of the second electrode 162 to prevent them from passing through the plasma. In one embodiment, the dielectric portion 18 may also be separated into a portion providing the first region 181 and a portion providing the second region 182. The insulating portion 11i may be sandwiched between the outer peripheral surface of the portion providing the first region 181 and the inner peripheral surface of the portion providing the second region 182.

[0045] The plurality of power sources in the plasma processing apparatus 1 may also include suction cup power sources 31, 32, and 33. Each of the suction cup power sources 31, 32, and 33 is a DC power source or a variable DC power source. The suction cup power source 31 is connected to the first electrode 161 via a switch 31s, an electrode 163, and one or more wirings 165. Once a DC voltage from the suction cup power source 31 is applied to the first electrode 161, the substrate W is attracted to the first region 181 by electrostatic attraction and held by the substrate support portion 11A.

[0046] The suction cup power supply 32 is connected to the electrode 162a via a switch 32s and one or more wirings 166a. The suction cup power supply 33 is connected to the electrode 162b via a switch 33s and one or more wirings 166b. Once a DC voltage from the suction cup power supply 32 is applied to the electrode 162a and a DC voltage from the suction cup power supply 33 is applied to the electrode 162b, the edge ring ER will be attracted to the second region 182 by electrostatic attraction and held by the substrate support portion 11A.

[0047] The plasma processing apparatus 1 has a plurality of power supplies, including one or more high-frequency power supplies and one or more bias power supplies. In the example shown in FIG3, the plurality of power supplies includes a high-frequency power supply 51, a high-frequency power supply 52, a bias power supply 53, and a bias power supply 54.

[0048] High-frequency power supplies 51 and 52 constitute a plasma generating unit in one embodiment. Each of the high-frequency power supplies 51 and 52 generates high-frequency power with a frequency suitable for generating plasma from gas within the chamber 10. The high-frequency power generated by each of the high-frequency power supplies 51 and 52 has a frequency in the range of, for example, 13MHz to 150MHz.

[0049] The high-frequency power supply 51 is connected to the first electrode 161 via a matching device 51m, an electrode 163, and one or more wirings 165. The matching device 51m includes a matching circuit for matching the impedance of the load of the high-frequency power supply 51 with the output impedance of the high-frequency power supply 51.

[0050] The high-frequency power supply 52 is connected to the electrode 162a via a matching adapter 52m, a capacitor 54ca, and one or more wirings 166a. Furthermore, the high-frequency power supply 52 is connected to the electrode 162b via a matching adapter 52m, a capacitor 54cb, and one or more wirings 166b. The matching adapter 52m includes a matching circuit to match the impedance of the load of the high-frequency power supply 52 with the output impedance of the high-frequency power supply 52. ​​The capacitor 54ca provides DC isolation between the high-frequency power supply 52 and the chuck power supply 32. The capacitor 54cb provides DC isolation between the high-frequency power supply 52 and the chuck power supply 33.

[0051] Bias power supplies 53 and 54 generate bias power for introducing ions into the substrate W and the edge ring ER. The bias power may also be high-frequency bias power. High-frequency bias power has a frequency, for example, in the range of 100 kHz to 13.56 MHz. Alternatively, the bias power may be periodically generated voltage pulses. Voltage pulses have positive or negative polarity. Voltage pulses can be pulses with arbitrary waveforms. Voltage pulses can also be negative DC voltage pulses. The voltage pulses periodically generate repetition frequencies in the range of 100 kHz to 13.56 MHz.

[0052] The bias power supply 53 is connected to the first electrode 161 via a matching converter 53m, a capacitor 53c, an electrode 163, and one or more wirings 165. The matching converter 53m includes a matching circuit to match the impedance of the load of the bias power supply 53 with the output impedance of the bias power supply 53. The capacitor 53c is configured to DC isolate the bias power supply 53 from the chuck power supply 31.

[0053] The bias power supply 54 is connected to the electrode 162a via a matching adapter 54m, a capacitor 54ca, and one or more wirings 166a. Furthermore, the bias power supply 54 is connected to the electrode 162b via a matching adapter 54m, a capacitor 54cb, and one or more wirings 166b. The matching adapter 54m includes a matching circuit to match the impedance of the load of the bias power supply 54 with the output impedance of the bias power supply 54. The capacitor 54ca is configured to DC isolate the bias power supply 54 from the chuck power supply 32. The capacitor 54cb is configured to DC isolate the bias power supply 54 from the chuck power supply 33.

[0054] Since no electrodes are provided within the dielectric portion 18 in the plasma processing apparatus 1, the thickness of the dielectric portion 18 can be reduced. Therefore, the impedance between the first electrode 161 of the substrate 16 and the substrate W is reduced. Furthermore, the impedance between the electrodes 162a and 162b of the substrate 16 and the edge ring ER is reduced. As a result, bias power is efficiently supplied to the substrate W. Furthermore, bias power is efficiently supplied to the edge ring ER. Furthermore, high-frequency power is efficiently coupled to the plasma via the substrate W and the edge ring ER. Therefore, the bias power can be reduced. Furthermore, high-frequency power can be reduced. Therefore, heat generation at the electrodes, contacts, etc., in the substrate support portion 11A is suppressed.

[0055] Furthermore, since the base member 16b of the base 16 is formed of a dielectric or an insulator, the difference between the thermal expansion rate of the base 16 and the thermal expansion rate of the dielectric portion 18 is very small. Therefore, damage to the substrate support portion 11A caused by the difference between the thermal expansion rate of the base 16 and the thermal expansion rate of the dielectric portion 18 is suppressed.

[0056] In one embodiment, the dielectric portion 18 may also satisfy the following (1). 0.5×CW0 / SW< CFO / SF< 1.5×CW0 / SW… (1) In equation (1), CW0 is the electrostatic capacitance between the abutment 16 and the substrate W. SW is the area of ​​a main surface of the substrate W (e.g., the bottom surface, or the surface in contact with the plasma). CFO is the electrostatic capacitance between the abutment 16 and the edge ring ER. SF is the area of ​​a main surface of the edge ring (e.g., the bottom surface, or the surface in contact with the plasma). By satisfying equation (1), the difference between "the power density of the high-frequency power coupled to the plasma via the substrate W" and "the power density of the high-frequency power coupled to the plasma via the edge ring ER" is reduced. Therefore, the plasma density non-uniformity in the cavity is suppressed.

[0057] In one embodiment, the substrate support portion 11A may also be configured such that the electrostatic capacitance between the substrate W and the edge ring ER is less than 10nF or less than 3nF. This suppresses the electrical coupling between the substrate W and the edge ring ER.

[0058] Referring now to FIG4. FIG4 is a diagram illustrating a substrate support portion and a plurality of power sources of a plasma processing apparatus according to another exemplary embodiment. The substrate support portion 11B shown in FIG4 can be used as a substrate support portion 11 of the plasma processing apparatus 1. The substrate support portion 11B further includes one or more wirings 165a and one or more wirings 165b. The one or more wirings 165a and one or more wirings 165b extend between the top surface and the bottom surface of the base member 16b. The one or more wirings 165a connects the electrode 163 and the electrode 162a to each other. The one or more wirings 165b connect the electrode 163 and the electrode 162b to each other.

[0059] One or more wirings 165a and one or more wirings 165b may each be a through hole formed in the base member 16b. Alternatively, one or more wirings 165a and one or more wirings 165b may each be a conductor wire formed along the surface of the base member 16b.

[0060] In the example shown in FIG. 4, the plasma processing apparatus 1 does not include a high-frequency power supply 52 and a matching device 52m. In the example shown in FIG. 4, the high-frequency power supply 51 is connected to the electrode 162a via the matching device 51m, the electrode 163, and one or more wirings 165a. Furthermore, the high-frequency power supply 51 is connected to the electrode 162b via the matching device 51m, the electrode 163, and one or more wirings 165b. In the example shown in FIG. 4, the high-frequency power from a single high-frequency power supply 51 is distributed to the first electrode 161 and the second electrode 162. Moreover, the other configurations in the example shown in FIG. 4 are each the same as the corresponding configurations in the example shown in FIG. 3.

[0061] Referring to Figure 5 below. Figure 5 is a diagram illustrating the substrate support and a plurality of power supplies of a plasma processing apparatus according to another embodiment. As shown in Figure 5, the plasma processing apparatus 1 may also omit: a high-frequency power supply 52, a matching device 52m, a bias power supply 54, and a matching device 54m.

[0062] As shown in Figure 5, the high-frequency power supply 51 is connected to electrode 162a via matching adapter 51m, impedance circuit 56, capacitor 53ca, and wiring 166a. Furthermore, the high-frequency power supply 51 is connected to electrode 162b via matching adapter 51m, impedance circuit 56, capacitor 53cb, and wiring 166b. The bias power supply 53 is connected to electrode 162a via matching adapter 53m, impedance circuit 56, capacitor 53ca, and wiring 166a. Furthermore, the bias power supply 53 is connected to electrode 162b via matching adapter 53m, impedance circuit 56, capacitor 53cb, and wiring 166b. Capacitor 53ca is configured to DC isolate the high-frequency power supply 51 and bias power supply 53 from the chuck power supply 32. Capacitor 53cb is configured to DC isolate the high-frequency power supply 51 and bias power supply 53 from the chuck power supply 33.

[0063] The impedance circuit 56 has a variable impedance. The impedance circuit contains a variable impedance element, such as a variable capacitor. In the plasma processing apparatus 1 of the example shown in FIG. 5, high-frequency power from a single high-frequency power supply 51 is distributed to the first electrode 161 and the second electrode 162. Furthermore, in the plasma processing apparatus 1 of the example shown in FIG. 5, bias power from a single bias power supply 53 is distributed to the first electrode 161 and the second electrode 162. The respective distribution ratio of the high-frequency power and the bias power is set by adjusting the variable impedance of the impedance circuit 56. Moreover, the other configurations in the example shown in FIG. 5 are each the same as the corresponding configurations in the example shown in FIG. 3.

[0064] Referring now to FIG6. FIG6 is a diagram illustrating a substrate support portion and a plurality of power sources of a plasma processing apparatus according to another embodiment. The substrate support portion 11D shown in FIG6 can be used as a substrate support portion 11 of the plasma processing apparatus 1. The substrate support portion 11D has a base 16D instead of a base 16. The base 16D includes a first portion 161D and a second portion 162D.

[0065] Part 1 161D and Part 2 162D are each formed of a conductive material. Part 1 161D and Part 2 162D are each formed of a metal or a metal-ceramic composite material, such as aluminum.

[0066] Part 161D is located below the first region 181. Part 161D contains the center of the base 16D and is approximately disk-shaped. Part 262D is located below the second region 182. Part 262D extends circumferentially outward from the radial side of Part 161D. Part 262D may also be approximately annular when viewed from above. Part 262D is separate from Part 161D. The gap between Part 161D and Part 262D may be filled with insulating material (insulating part 11i) or dielectric material.

[0067] In one embodiment, the second part 162D may also include parts 162e and 162f. Parts 162e and 162f constitute a bipolar electrode. Parts 162e and 162f each extend circumferentially outward from the radial side of the first part 161D. Parts 162e and 162f may each be approximately annular when viewed from above. Part 162f may also extend circumferentially outward from the radial side of part 162e. Parts 162e and 162f are separated from each other. The gap between parts 162e and 162f may also be filled with an insulating material or a dielectric material.

[0068] The suction cup power supply 31 is connected to the first part 161D via the switch 31s. Once the DC voltage from the suction cup power supply 31 is applied to the first part 161D, the substrate W will be attracted to the first region 181 by electrostatic attraction and held by the substrate support part 11D.

[0069] The suction cup power supply 32 is connected to portion 162e via switch 32s. The suction cup power supply 33 is connected to portion 162f via switch 33s. Once a DC voltage from the suction cup power supply 32 is applied to portion 162e and a DC voltage from the suction cup power supply 33 is applied to portion 162f, the edge ring ER will be attracted to the second region 182 by electrostatic attraction and held by the substrate support portion 11D.

[0070] High-frequency power supply 51 is connected to section 161D via matching adapter 51m. High-frequency power supply 52 is connected to section 162e via matching adapter 52m and capacitor 54ca. Furthermore, high-frequency power supply 52 is connected to section 162f via matching adapter 52m and capacitor 54cb.

[0071] Bias power supply 53 is connected to part 161D via matching connector 53m and capacitor 53c. Bias power supply 54 is connected to part 162e via matching connector 54m and capacitor 54ca. Furthermore, bias power supply 54 is connected to part 162f via matching connector 54m and capacitor 54cb.

[0072] Since no electrodes are provided in the dielectric portion 18 within the substrate support portion 11D, the thickness of the dielectric portion 18 can be reduced. Therefore, the impedance between the first portion 161D of the base 16D and the substrate W, and the impedance between the second portion 162D of the base 16D and the edge ring ER, will decrease. As a result, bias power will be efficiently supplied to the substrate W and the edge ring ER.

[0073] In one embodiment, the dielectric portion 18 can also satisfy the following (2). 0.5×CW0 / SW< CFO / SF< 1.5×CW0 / SW… (2) In equation (2), CW0 is the electrostatic capacitance between the abutment 16D and the substrate W. SW is the area of ​​one main surface of the substrate W (e.g., the bottom surface, or the surface in contact with the plasma). CFO is the electrostatic capacitance between the abutment 16D and the edge ring ER. SF is the area of ​​one main surface of the edge ring ER (e.g., the bottom surface, or the surface in contact with the plasma). By satisfying equation (2), the difference between "the power density of the high-frequency power coupled to the plasma via the substrate W" and "the power density of the high-frequency power coupled to the plasma via the edge ring ER" is reduced. Therefore, the non-uniformity of plasma density in the cavity is suppressed.

[0074] In one embodiment, the substrate support portion 11D may also be configured such that the electrostatic capacitance between the substrate W and the edge ring ER is less than 10nF or less than 3nF. This will suppress the electrical coupling between the substrate W and the edge ring ER.

[0075] Referring to Figure 7 below. Figure 7 is a diagram illustrating the substrate support and a plurality of power supplies of a plasma processing apparatus according to another embodiment. As shown in Figure 7, the plasma processing apparatus 1 may also omit: a high-frequency power supply 52, a matching device 52m, a bias power supply 54, and a matching device 54m.

[0076] As shown in Figure 7, the high-frequency power supply 51 is connected to portion 162e via matching connector 51m, impedance circuit 56, and capacitor 53ca. Furthermore, the high-frequency power supply 51 is connected to portion 162f via matching connector 51m, impedance circuit 56, and capacitor 53cb. The bias power supply 53 is connected to portion 162e via matching connector 53m, impedance circuit 56, and capacitor 53ca. Furthermore, the bias power supply 53 is connected to portion 162f via matching connector 53m, impedance circuit 56, and capacitor 53cb.

[0077] In the plasma processing apparatus 1 of the example shown in FIG. 7, the high-frequency power from a single high-frequency power supply 51 is distributed to the first part 161D and the second part 162D. Furthermore, in the plasma processing apparatus 1 of the example shown in FIG. 7, the bias power from a single bias power supply 53 is distributed to the first part 161D and the second part 162D. The respective distribution ratios of the high-frequency power and the bias power are set by adjusting the variable impedance of the impedance circuit 56. Moreover, the other configurations in the example shown in FIG. 7 are each the same as the corresponding configurations in the example shown in FIG. 6.

[0078] Referring now to FIG8. FIG8 is a diagram illustrating a substrate support portion and a plurality of power sources of a plasma processing apparatus according to another embodiment. In contrast to the substrate support portions 11A and 11B described above, the second electrode 162 comprises two electrodes, while in the substrate support portion 11E shown in FIG8, the second electrode 162E is configured as a single electrode. The second electrode 162E is connected to a wiring 166 extending from the bottom surface of the base member 16b through its edge surface. Alternatively, one or more wirings 165 may each pass through a groove formed on the periphery of the base member 16b, thereby connecting the electrode 163 to the first electrode 161.

[0079] For the second electrode 162E, the suction cup power supply 32 is connected via switch 32s and wiring 166. Furthermore, the high-frequency power supply 52 is connected to the second electrode 162E via matching adapter 52m, capacitor 54c, and wiring 166. Furthermore, the bias power supply 54 is connected to the second electrode 162E via matching adapter 54m, capacitor 54c, and wiring 166. Also, the high-frequency power from the high-frequency power supply 51 can be distributed to the first electrode 161 and the second electrode 162E. Furthermore, the bias power from the bias power supply 53 can also be distributed to the first electrode 161 and the second electrode 162E.

[0080] Referring now to FIG9. FIG9 is a diagram illustrating a substrate support portion and a plurality of power sources of a plasma processing apparatus according to another embodiment. In contrast to the substrate support portion 11D described above, the second portion 162D comprises two portions 162e and 162f, while in the base 16F of the substrate support portion 11F shown in FIG9, the second portion 162F is configured as a single portion.

[0081] For Part 2 162F, the suction cup power supply 32 is connected via switch 32s. Furthermore, the high-frequency power supply 52 is connected to Part 2 162F via matching adapter 52m and capacitor 54c. Furthermore, the bias power supply 54 is connected to Part 2 162F via matching adapter 54m and capacitor 54c. Also, the high-frequency power from the high-frequency power supply 51 can be distributed between Part 1 161D and Part 2 162F. Furthermore, the bias power from the bias power supply 53 can also be distributed between Part 1 161D and Part 2 162F.

[0082] Referring now to FIG10. FIG10 is a diagram illustrating a substrate support and a plurality of power sources of a plasma processing apparatus according to another embodiment. The example shown in FIG10 is a variation of the example shown in FIG3. In the example shown in FIG10, a flow path 16f is formed in the base 16. A heat medium (e.g., a coolant) from a supply is supplied to the flow path 16f. The heat medium flows in the flow path 16f and then returns to the supply. The flow path 16f can be formed to have a large cross-sectional area without compromising the mechanical strength of the base 16. Furthermore, the flow path 16f can also be formed in the base 16 in the above-described examples other than those shown in FIG3.

[0083] Referring now to FIG11. FIG11 is a diagram illustrating a substrate support and a plurality of power sources of a plasma processing apparatus according to another embodiment. The example shown in FIG11 is a variation of the example shown in FIG6. In the example shown in FIG11, a flow path 16f is formed in the base 16D. A heat medium (e.g., a coolant) from a supply is supplied to the flow path 16f. The heat medium flows in the flow path 16f and then returns to the supply. The flow path 16f can be formed to have a large cross-sectional area without compromising the mechanical strength of the base 16D. Furthermore, the flow path 16f can also be formed in the base 16D in the above-mentioned examples other than those shown in FIG6. Moreover, the flow path 16f can also be formed in the base 16F in the example shown in FIG9.

[0084] Referring now to FIG12. FIG12 is a flowchart of an exemplary embodiment of a substrate processing method. The substrate processing method shown in FIG12 (hereinafter referred to as "method MT") can be performed using the plasma processing apparatus 1 described above. In method MT, various parts of plasma processing apparatus 1 can be controlled by control unit 2. Method MT includes step Sta, step STb, step STc, and step STd.

[0085] In step STa, the substrate W is placed on the dielectric portion 18 of the substrate support. Steps STb, STc, and STd are performed while the substrate W is placed on the dielectric portion 18.

[0086] In step STb, plasma is generated within chamber 10 using a plasma generating unit. In step STb, processing gas is supplied into chamber 10 from gas supply unit 20. Furthermore, in step STb, the pressure within chamber 10 is reduced to a specified pressure using exhaust system 40. Furthermore, in step STb, high-frequency power is supplied to generate plasma from the processing gas.

[0087] In step STc, the substrate W is held in place by the substrate support by applying voltage with the suction cup power supply 31. Alternatively, the edge ring ER can also be held in place by the substrate support in step STc by applying voltage with the suction cup power supplies 32 and 33. Or, the holding of the edge ring ER by the substrate support can begin before step STb.

[0088] Step STd is performed during plasma generation in step STb. In step STd, a bias voltage is supplied so that ions from the plasma are introduced into the substrate W.

[0089] The above descriptions have covered various illustrative embodiments, but are not limited to the embodiments described above. Various additions, omissions, substitutions, and changes are also possible. Furthermore, the constituent units of different embodiments can be combined to form another embodiment.

[0090] For example, the high-frequency power from the high-frequency power source may be supplied to the upper electrode instead of the substrate support. Furthermore, in another embodiment, the plasma processing apparatus may be a type other than capacitively coupled plasma processing apparatus. Such plasma processing apparatus may also be: inductively coupled plasma processing apparatus, electron cyclotron resonance (ECR) plasma processing apparatus, or plasma processing apparatus that uses surface waves such as microwaves to generate plasma.

[0091] From the above description, it can be understood that the various embodiments of the present invention are described in this specification for illustrative purposes, and various modifications can be made without departing from the scope and spirit of the present invention. Therefore, there is no intention to limit the various embodiments disclosed in this specification, and the true scope and spirit are disclosed by the appended claims. [Simplified Explanation of the Diagram]

[0008] [Figure 1] A schematic diagram of an exemplary embodiment of a plasma processing apparatus. [Figure 2] A schematic diagram of an exemplary embodiment of a plasma processing apparatus. [Figure 3] A diagram of a substrate support and a plurality of power sources of an exemplary embodiment of a plasma processing apparatus. [Figure 4] A diagram of a substrate support and a plurality of power sources of another exemplary embodiment of a plasma processing apparatus. [Figure 5] A diagram of a substrate support and a plurality of power sources of yet another exemplary embodiment of a plasma processing apparatus. [Figure 6] A diagram of a substrate support and a plurality of power sources of yet another exemplary embodiment of a plasma processing apparatus. [Figure 7] A diagram of a substrate support and a plurality of power sources of yet another exemplary embodiment of a plasma processing apparatus. [Figure 8] A diagram of a substrate support and a plurality of power sources of yet another exemplary embodiment of a plasma processing apparatus. [Figure 9] A diagram illustrating the substrate support and a plurality of power sources of a plasma processing apparatus according to another embodiment. [Figure 10] A diagram illustrating the substrate support and a plurality of power sources of a plasma processing apparatus according to another embodiment. [Figure 11] A diagram illustrating the substrate support and a plurality of power sources of a plasma processing apparatus according to another embodiment. [Figure 12] A flowchart of a substrate processing method according to an embodiment.

Claims

1. A plasma processing apparatus, comprising: a chamber; a substrate support disposed within the chamber; a plasma generation unit that generates plasma within the chamber; a bias power supply that generates bias power for introducing ions from the plasma to a substrate; and a chuck power supply that generates a voltage supplied to the substrate support for holding the substrate by electrostatic attraction; the bias power supply being high-frequency power or a periodically generated voltage pulse; the substrate support comprising a base and a dielectric portion; the base comprising a base member formed of a dielectric or an insulator, and an electrode formed on a top surface of the base member, the electrode constituting the top surface of the base; the dielectric portion providing a support surface on which a substrate is mounted, and extending from the top surface of the base to the support surface, and being formed solely of a dielectric; the bias power supply and the chuck power supply being electrically connected to the electrode of the base; the support surface comprising a first region on which a substrate is mounted, and a second region on which an edge ring is mounted. The electrode is a first electrode disposed below the first region; the base further includes a second electrode; the second electrode is disposed below the second region and forms the top surface of the base, and is separated from the first electrode; the bias power supply or another bias power supply and another suction cup power supply are electrically connected to the second electrode.

2. The plasma treatment apparatus as claimed in claim 1, wherein, The bias power supply is electrically connected to the electrode via a capacitor and is DC isolated from the suction cup power supply.

3. The plasma processing apparatus as described in claim 1 or 2, wherein, The bias power supply and the suction cup power supply are electrically connected to the electrode via wiring extending between the top and bottom surfaces of the base member.

4. The plasma treatment apparatus as described in claim 1 or 2, wherein: The plasma generating unit includes a high-frequency power supply electrically connected to the electrode of the base.

5. The plasma treatment apparatus as claimed in claim 1, wherein, The second electrode comprises two electrodes constituting a bipolar electrode; the other suction cup power supply comprises two power supplies respectively connected to the two electrodes.

6. The plasma treatment apparatus as described in claim 1 or 5, wherein, The bias power supply or another bias power supply is electrically connected to the second electrode via a capacitor and is DC isolated from the other suction cup power supply.

7. The plasma treatment apparatus as claimed in item 1 or 5, wherein: The bias power supply or the other bias power supply, and the other suction cup power supply, are electrically connected to the second electrode via wiring extending between the top and bottom surfaces of the base member.

8. A plasma processing apparatus, comprising: a chamber; a substrate support disposed within the chamber; a plasma generation unit that generates plasma within the chamber; a bias power source that generates bias power for introducing ions from the plasma to a substrate; and a suction cup power source that generates a voltage supplied to the substrate support for holding the substrate by electrostatic attraction; the bias power source being high-frequency power or a periodically generated voltage pulse; the substrate support comprising a base and a dielectric portion; the dielectric portion having a support surface on which the substrate is mounted and extending from the top surface of the base to the support surface, and being formed solely of dielectric material; the support surface comprising a first region on which the substrate is mounted and a second region on which an edge ring is mounted; the base comprising a first portion and a second portion, the first portion being formed of a conductive material and disposed below the first region; the second portion being formed of a conductive material and disposed below the second region, and separated from the first portion; The bias power supply and the suction cup power supply are electrically connected to the first part; the bias power supply or another bias power supply and another suction cup power supply are electrically connected to the second part.

9. The plasma treatment apparatus as claimed in claim 8, wherein, The second part comprises two parts constituting a bipolar electrode; the other suction cup power supply comprises two power supplies respectively connected to the two parts.

10. The plasma processing apparatus as claimed in item 8 or 9, wherein, The bias power supply is electrically connected to the first part via a capacitor and is DC isolated from the suction cup power supply; the bias power supply or the other bias power supply is electrically connected to the second part via a capacitor and is DC isolated from the other suction cup power supply.

11. The plasma processing apparatus as claimed in item 8 or 9, wherein: The plasma generating unit includes a high-frequency power supply electrically connected to the first part of the base.

12. A substrate processing method using a plasma processing apparatus as claimed in any one of claims 1 to 11; the substrate processing method comprising the steps of: placing a substrate on a dielectric portion of a substrate support; generating plasma in a chamber using a plasma generating portion; holding the substrate by the substrate support portion by supplying a voltage from a chuck power source; and introducing ions from the plasma into the substrate by supplying a bias power source from a bias power source.

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