JP2023025675A - Plasma processing apparatus and plasma processing method - Google Patents

Abstract

To provide a technique capable of reducing a difference between an upper end position of a sheath on a substrate and an upper end position of a sheath on an edge ring, in a cycle of an electric bias energy supplied to the edge ring.SOLUTION: In a plasma processing apparatus, a first electric bias energy and a second electric bias energy are respectively supplied to a substrate and an edge ring. A first high-frequency power and a second high-frequency power are respectively coupled with a plasma via the substrate and the edge ring. A cycle of the second electric bias energy includes a time period in which a voltage of the second electric bias energy has a positive level to an average value within its cycle. In the time period, a power level of the first high-frequency power or a power level of the second high-frequency power is set so as to reduce a difference between an upper end position of a sheath on the substrate and an upper end position of a sheath on the edge ring.SELECTED DRAWING: Figure 3

Description

An exemplary embodiment of the present disclosure relates to a plasma processing apparatus and a plasma processing method.

Plasma processing apparatuses are used in plasma processing of substrates. A plasma processing apparatus includes a chamber and a substrate support. A substrate support is provided within the chamber. The substrate support supports the substrate and edge ring (or focus ring). The edge ring thickness is reduced by the plasma treatment. Patent Literature 1 listed below discloses a plasma processing apparatus configured to apply a negative DC voltage to an edge ring when the thickness of the edge ring is small. When a negative DC voltage is applied, the sheath on the edge ring becomes thicker and the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring is eliminated.

JP 2008-227063 A

The present disclosure provides techniques for reducing the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring within the period of the electrical bias energy supplied to the edge ring.

In one exemplary embodiment, a plasma processing apparatus is provided. A plasma processing apparatus includes a chamber, a substrate support, at least one radio frequency power supply, and at least one bias power supply. A substrate support is provided within the chamber and configured to support the substrate and the edge ring. The at least one radio frequency power source is configured to generate a first radio frequency power that couples to the plasma through the substrate and above the substrate and a second radio frequency power that couples to the plasma through the edge ring and above the edge ring. It is At least one bias power supply is configured to generate a first electrical bias energy supplied to the substrate and a second electrical bias energy supplied to the edge ring. The first electrical bias energy and the second electrical bias energy have waveforms that repeat with a bias period having a time length that is the reciprocal of the bias frequency. A bias period includes a first period and a second period. In the first period, the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level with respect to the average value of the voltage within the bias period. In the second period, each voltage of the first electrical bias energy and the second electrical bias energy has a negative level with respect to the average value. In the first period, the power level of the first high frequency power or the power level of the second high frequency power is set so as to reduce the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring. is set.

According to one exemplary embodiment, the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring can be small within a period of the electrical bias energy supplied to the edge ring. It becomes possible.

1 schematically illustrates a plasma processing apparatus according to one exemplary embodiment; FIG. 1 schematically illustrates a plasma processing apparatus according to one exemplary embodiment; FIG. 1 schematically illustrates a plasma processing apparatus according to one exemplary embodiment; FIG. 4 is a timing chart associated with a plasma processing apparatus according to one exemplary embodiment; FIG. 5(a) is a diagram showing the upper end position of the sheath when the thickness of the edge ring is larger than a predetermined value, and FIG. 5(b) is a diagram showing the edge ring having a thickness smaller than the predetermined value. FIG. 10 is a diagram showing the position of the upper end of the sheath in this case. FIG. 2 schematically illustrates a plasma processing apparatus according to another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; 1 is a flow diagram of a plasma processing method according to one exemplary embodiment;

Various exemplary embodiments are described in detail below with reference to the drawings. In addition, suppose that the same code|symbol is attached|subjected to the part which is the same or equivalent in each drawing.

1 and 2 are schematic diagrams of a plasma processing apparatus according to one exemplary embodiment.

In one embodiment, a plasma processing system includes a plasma processing apparatus 1 and a controller 2 . The plasma processing apparatus 1 includes a plasma processing chamber 10 , a substrate support section 11 and a plasma generation section 12 . Plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas inlet for supplying at least one process gas to the plasma processing space and at least one gas outlet for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply section 20, which will be described later, and the gas discharge port is connected to an exhaust system 40, which will be described later. The substrate support 11 is arranged in the plasma processing space and has a substrate support surface for supporting the substrate.

The plasma generator 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. Plasma formed in the plasma processing space includes capacitively coupled plasma (CCP), inductively coupled plasma (ICP), ECR plasma (Electron-Cyclotron-resonance plasma), helicon wave excited plasma (HWP: Helicon Wave Plasma), surface wave plasma (SWP: Surface Wave Plasma), or the like.

Controller 2 processes computer-executable instructions that cause plasma processing apparatus 1 to perform the various steps described in this disclosure. Controller 2 may be configured to control elements of plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1 . The control unit 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. Processing unit 2a1 can be configured to perform various control operations based on programs stored in storage unit 2a2. The storage 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 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

A configuration example of a capacitively-coupled plasma processing apparatus as an example of the plasma processing apparatus 1 will be described below. The capacitively-coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, and an exhaust system 40. As shown in FIG. Further, the plasma processing apparatus 1 includes a substrate support section 11 and a gas introduction section. The gas introduction is configured to introduce at least one process gas into the plasma processing chamber 10 . The gas introduction section includes a showerhead 13 . A substrate support 11 is positioned within the plasma processing chamber 10 . The showerhead 13 is arranged above the substrate support 11 . In one embodiment, showerhead 13 forms at least a portion of the ceiling of plasma processing chamber 10 . The plasma processing chamber 10 has a plasma processing space 10 s defined by a showerhead 13 , side walls 10 a of the plasma processing chamber 10 and a substrate support 11 . Side wall 10a is grounded. The showerhead 13 and substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10 .

A substrate support 11 is provided within the plasma processing chamber 10 . The substrate support 11 is configured to support the substrate W and the edge ring ER placed thereon. The edge ring ER has a ring shape and is made of a material such as silicon, silicon carbide, or quartz. A substrate W is placed on the substrate support 11 and within the area surrounded by the edge ring ER. Also, although not shown, the substrate supporter 11 may include a temperature control module configured to adjust at least one of the substrate W and the edge ring ER to a target temperature. The temperature control module may include heaters, heat transfer media, flow paths, or combinations thereof. A heat transfer fluid, such as brine or gas, flows through the channel. Further, the substrate support section 11 may include a heat transfer gas supply section configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface.

The showerhead 13 is configured to introduce at least one processing gas from the gas supply 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas introduction ports 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s through a plurality of gas introduction ports 13c. Showerhead 13 also includes a conductive member. A conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas introduction part may include one or more side gas injectors (SGI: Side Gas Injectors) attached to one or more openings formed in the side wall 10a.

The gas supplier 20 may include one or more gas sources 21 and at least one or more flow controllers 22 . In one embodiment, gas supply 20 is configured to supply one or more process gases from respective gas sources 21 through respective flow controllers 22 to showerhead 13 . Each flow controller 22 may include, for example, a mass flow controller or a pressure controlled flow controller. Additionally, gas supply 20 may include one or more flow modulation devices that modulate or pulse the flow of one or more process gases.

The exhaust system 40 may be connected to a gas outlet 10e provided at the bottom of the plasma processing chamber 10, for example. Exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve regulates the pressure in the plasma processing space 10s. Vacuum pumps may include turbomolecular pumps, dry pumps, or combinations thereof.

In the following, FIG. 3 will be referred to in addition to FIG. FIG. 3 is a schematic diagram of a plasma processing apparatus according to one exemplary embodiment. The substrate support section 11 has a first base 111 a , a second base 111 b and an electrostatic chuck 113 . The first base 111a and the second base 111b are made of a conductor such as aluminum. The first base 111a has a substantially disk shape. The second base 111b has a substantially ring shape. The second base 111b extends in the circumferential direction outside the first base 111a in the radial direction so as to surround the first base 111a. A dielectric region 111c may be interposed between the first base 111a and the second base 111b.

The electrostatic chuck 113 is provided on the first base 111a and the second base 111b. The substrate support portion 11 includes a first region 11R1 composed of a central portion of the electrostatic chuck 113 and a first base 111a. The substrate W is placed on the electrostatic chuck 113 on the first region 11R1. The substrate support portion 11 includes a second region 11R2 composed of the peripheral portion of the electrostatic chuck 113 and the second base 111b. The edge ring ER is placed on the second region 11R2 and on the electrostatic chuck 113. As shown in FIG.

The electrostatic chuck 113 has a dielectric portion 113d. Dielectric portion 113d is formed of a dielectric such as aluminum nitride or aluminum oxide. The dielectric portion 113d has a substantially disk shape. The first region 11R1 includes the central portion of the dielectric portion 113d. The second region 11R2 includes the peripheral portion of the dielectric portion 113d.

The electrostatic chuck 113 further has a chuck electrode 113a. The chuck electrode 113a is a film made of a conductor, and is provided in the dielectric portion 113d within the first region 11R1. A DC power supply 50p is electrically connected to the chuck electrode 113a through a switch 50s. When a DC voltage from the DC power supply 50p is applied to the chuck electrode 113a, electrostatic attraction is generated between the substrate W and the electrostatic chuck 113. As shown in FIG. The generated electrostatic attraction attracts the substrate W to the electrostatic chuck 113 and holds it by the electrostatic chuck 113 .

The electrostatic chuck 113 may further have chuck electrodes 113b and 113c. Each of the chuck electrodes 113b and 113c is a film made of a conductor. Chuck electrodes 113b and 113c may have an annular shape. The chuck electrodes 113b and 113c are provided in the dielectric portion 113d within the second region 11R2. A DC power supply 51p is electrically connected to the chuck electrode 113b through a switch 51s. A DC power supply 52p is electrically connected to the chuck electrode 113c through a switch 52s. When the DC voltage from the DC power supply 51p is applied to the chuck electrode 113b and the DC voltage from the DC power supply 52p is applied to the chuck electrode 113c, electrostatic attraction is generated between the edge ring ER and the electrostatic chuck 113. . The generated electrostatic attraction attracts the edge ring ER to the electrostatic chuck 113 and holds it by the electrostatic chuck 113 .

The plasma processing apparatus 1 includes a high frequency power supply 31 (first high frequency power supply), a high frequency power supply 32 (second high frequency power supply), a bias power supply 41 (first bias power supply), and a bias power supply 42 (second bias power supply). It has

The high frequency power supply 31 is configured to generate high frequency power RF1 (first high frequency power) to generate plasma within the chamber 10 . The high frequency power RF1 has a frequency of, for example, 13 MHz or more and 150 MHz or less. Radio frequency power RF1 is supplied to the substrate support 11 through the substrate support 11 and the substrate W so as to couple to the plasma on the substrate W. As shown in FIG. In the embodiment of FIG. 3, the high frequency power supply 31 is electrically connected to the first base 111a through the matching box 31m. The matching box 31m includes a matching circuit. The matching circuit of the matching box 31m has variable impedance. The matching circuit of the matching box 31m is controlled by the controller 30, which will be described later. The impedance of the matching circuit of the matching unit 31m is adjusted so as to match the impedance on the load side of the high frequency power supply 31 with the output impedance of the high frequency power supply 31 .

The radio frequency power supply 32 is configured to generate radio frequency power RF2 (second radio frequency power) to generate plasma within the chamber 10 . The high-frequency power RF2 has a frequency of, for example, 13 MHz or more and 150 MHz or less, like the high-frequency power RF1. Radio frequency power RF2 is supplied to the substrate support 11 through the substrate support 11 and the edge ring ER to couple to the plasma on the edge ring ER. In the embodiment of FIG. 3, the high frequency power supply 32 is electrically connected to the second base 111b via a matching box 32m. The matching box 32m includes a matching circuit. The matching circuit of the matching box 32m has variable impedance. The matching circuit of the matching box 32m is controlled by the controller 30. FIG. The impedance of the matching circuit of the matching unit 32m is adjusted so as to match the impedance on the load side of the high frequency power supply 32 with the output impedance of the high frequency power supply 32. FIG.

The bias power supply 41 is configured to generate electrical bias energy BE1 (first electrical bias energy). Electrical bias energy BE 1 is supplied to the substrate W via the substrate support 11 . An electrical bias energy BE1 is applied to the substrate W to adjust the energy of the ions supplied to the substrate W from the plasma. In the embodiment of FIG. 3, the bias power supply 41 is electrically connected to the first base 111a.

Bias power supply 42 is configured to generate electrical bias energy BE2 (second electrical bias energy). Electrical bias energy BE2 is supplied to edge ring ER via substrate support 11 . An electrical bias energy BE2 is supplied to the edge ring ER to adjust the energy of the ions supplied from the plasma to the edge ring ER. In the embodiment of FIG. 3, the bias power supply 42 is electrically connected to the second base 111b.

4 together with FIGS. 2 and 3. FIG. FIG. 4 is a timing chart associated with a plasma processing apparatus according to one exemplary embodiment. FIG. 4 shows respective waveforms (voltage waveforms) of the electric bias energy BE1 and the electric bias energy BE1. FIG. 4 also shows the level L _BE1 of the electrical bias energy BE1 and the level L _BE2 of the electrical bias energy BE2. FIG. 4 also shows a power level P _-RF1 of the high-frequency power RF1 and a power level P- _RF2 of the high-frequency power RF2.

Each of the electrical bias energy BE1 and the electrical bias energy BE2 has a waveform that repeats with a cycle CY (waveform cycle) having a time length that is the reciprocal of the bias frequency. The bias frequency is, for example, a frequency of 100 kHz or more and 13.56 MHz or less.

In one embodiment, each of the electrical bias energy BE1 and the electrical bias energy BE2 may be radio frequency power having a bias frequency, ie radio frequency bias power LF. The high-frequency bias power LF has a sinusoidal waveform in the period CY (waveform period), that is, the bias period. Cycle CY has a time length that is the reciprocal of the bias frequency.

When the electric bias energy BE1 is the high-frequency bias power LF, the bias power supply 41 is connected to the first base 111a through the matching box 41m. The matching box 41m includes a matching circuit. The matching circuit of the matching box 41m has variable impedance. The matching circuit of the matching box 41m is controlled by the controller 30. FIG. The impedance of the matching circuit of the matching unit 41m is adjusted so as to match the impedance on the load side of the bias power supply 41 with the output impedance of the bias power supply 41 .

When the electric bias energy BE2 is the high-frequency bias power LF, the bias power supply 42 is connected to the second base 111b through the matching box 42m. The matching box 42m includes a matching circuit. A matching circuit of the matching unit 42m has a variable impedance. The matching circuit of the matching box 42m is controlled by the controller 30. FIG. The impedance of the matching circuit of the matching unit 42m is adjusted so as to match the impedance on the load side of the bias power supply 42 with the output impedance of the bias power supply 42. FIG.

In another embodiment, each of electrical bias energy BE1 and electrical bias energy BE2 is a pulse of voltage generated periodically at time intervals (i.e., period CY or waveform period) having a time length that is the reciprocal of the bias frequency. It may be PV. The voltage pulse PV used as the electrical bias energy BE1 and the electrical bias energy BE2 may be a negative voltage pulse or a negative DC voltage pulse. The voltage pulse PV may have an arbitrary waveform such as a triangular wave or a square wave. If a voltage pulse is used as the electrical bias energy BE1, instead of the matching box 41m, a filter may be connected to the bias power supply 41 to cut off the high frequency power. Further, when a voltage pulse is used as the electrical bias energy BE2, instead of the matching box 42m, a filter may be connected to the bias power supply 42 so as to cut off the high frequency power.

A cycle CY (waveform cycle) includes a first period T1 and a second period T2. In the first period T1, each voltage of the electrical bias energy BE1 and the electrical bias energy BE2 has a positive level with respect to the average value of the voltages within the cycle CY. In the second period T2, each voltage of the electrical bias energy BE1 and the electrical bias energy BE2 has a negative level with respect to the average value.

The high frequency power supply 31 may change the frequency of the high frequency power RF1 within the cycle CY in order to suppress the reflection of the high frequency power RF1 from the load. Thus, the period CY is divided into a number of phase periods. The frequency of the high-frequency power RF1 for each of the plurality of phase periods within the cycle CY is set using a time series of frequencies prepared in advance. The frequency time series can be specified from the control unit 30 to the high frequency power supply 31 .

Further, the high-frequency power supply 32 may change the frequency of the high-frequency power RF2 within the period CY in order to suppress the reflection of the high-frequency power RF2 from the load. The frequency of the high-frequency power RF2 for each of the plurality of phase periods within the period CY is set using a time series of frequencies prepared in advance. The frequency time series can be specified from the control unit 30 to the high frequency power supply 32 .

The control unit 30 is configured to control the high frequency power source 31 , the high frequency power source 32 , the bias power source 41 and the bias power source 42 . The control unit 30 may be composed of a processor such as a CPU. Note that the control unit 2 may also serve as the control unit 30 .

5(a) and 5(b) will be referred to together with FIGS. 2 to 4. FIG. FIG. 5(a) is a diagram showing the upper end position of the sheath when the thickness of the edge ring is larger than a predetermined value, and FIG. 5(b) is a diagram showing the edge ring having a thickness smaller than the predetermined value. FIG. 10 is a diagram showing the position of the upper end of the sheath in this case.

As shown in FIGS. 5A and 5B, the thickness of the sheath is small during the first period T1, and the position of the upper end SH _T1 of the sheath during the first period T1 is low. On the other hand, the thickness of the sheath is large in the second period T2, and the position of the upper end SH _T2 of the sheath in the second period T2 is high. The position of the upper end of the sheath (that is, the upper end position of the sheath) is the position in the height direction of the interface between the sheath and the plasma.

When the thickness TH _ER of the edge ring ER is a predetermined value TH _P , for example, when the position of the top surface of the edge ring ER in the height direction is equal to the position of the top surface of the substrate W in the height direction, the thickness of the edge ring ER is is equal to the upper end position of the sheath on the substrate W. Hereinafter, the level L _BE2 of the electrical bias energy BE2 in this case will be referred to as a reference level L _REF2 . Also, the power level P-- _RF1 of the high-frequency power RF1 in this case is referred to as a reference power level P-- _REF1 . Also, the power level P-- _RF2 of the high-frequency power RF2 in this case is referred to as a reference power level P-- _REF2 .

When the thickness TH _ER of the edge ring ER is greater than the predetermined value TH _P and the level L _BE2 is the reference level L _REF2 , the upper end position of the sheath on the edge ring ER is indicated by the broken line in FIG. 5(a). is higher than the upper end position of the sheath on the substrate W, as shown in FIG. On the other hand, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value TH _P and the level L _BE2 is the reference level L _REF2 , the position of the upper end of the sheath on the edge ring ER is indicated by the dashed line in FIG. is lower than the upper end position of the sheath on the substrate W as indicated by .

In the plasma processing apparatus 1, the level L _BE2 of the electric bias energy BE2 is adjusted in order to reduce the difference between the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER within the period CY. be. Also, the power level P-RF1 of the high-frequency power _RF1 and/or the power level P-RF2 of the high-frequency power _RF2 are adjusted. The level L _BE2 of the electrical bias energy BE2 and the power level P _RF1 of the high frequency power RF1 and the power level P RF2 of the high frequency power _RF2 can be controlled by the controller 30 .

In the second period T2, the thickness of the sheath on the substrate W and the thickness of the sheath on the edge ring ER are mainly determined by the level L _BE1 of the electrical bias energy BE1 and the level L _BE2 of the electrical bias energy BE2. be. In the second period T2, in order to reduce the difference between the top position of the sheath on the substrate W and the top position of the sheath on the edge ring ER, the level L _BE2 of the electrical bias energy BE2 is increased to It is set to increase with decreasing thickness _THER . The level L _BE2 of the electrical bias energy BE2 can be specified from the controller 30 to the bias power supply 42 .

Specifically, when the thickness TH _ER of the edge ring ER is greater than the predetermined value TH _P , the level L _BE2 is set to a level lower than the reference level L _REF2 , as shown in FIG. This reduces the difference between the position of the sheath upper end SH _T2 on the substrate W and the position of the sheath upper end SH _T2 on the edge ring ER, as indicated by the solid line in FIG. 5(a). Note that the thickness TH _ER of the edge ring ER may be obtained optically or electrically by a sensor. Alternatively, the thickness T _ER of the edge ring ER may be estimated from the length of time the edge ring ER is exposed to the plasma.

On the other hand, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value _THP , the level L _BE2 is set higher than the reference level L _REF2 as shown in FIG. This reduces the difference between the position of the sheath upper end SH _T2 on the substrate W and the position of the sheath upper end SH _T2 on the edge ring ER, as indicated by the solid line in FIG. 5(b).

Note that the higher the level L _BE1 of the electrical bias energy BE1, the larger the absolute value of the negative bias potential of the substrate W, and the thicker the sheath on the substrate W becomes. Also, the higher the level L _BE2 of the electrical bias energy BE2, the larger the absolute value of the negative bias potential of the edge ring ER and the thicker the sheath on the edge ring ER. If the electrical bias energy BE1 is the high frequency bias power LF, the level L _BE1 is the power level of the electrical bias energy BE1. If the electrical bias energy BE2 is the high frequency bias power LF, the level L _BE2 is the power level of the electrical bias energy BE2. If the electrical bias energy BE1 is a voltage pulse PV, the level L _BE1 increases as the voltage level of the voltage pulse PV increases in the negative direction. Also, if the electrical bias energy BE2 is a voltage pulse PV, the level L _BE2 increases as the voltage level of the voltage pulse PV increases in the negative direction.

In the first period T1, the thickness of the sheath on the substrate W and the thickness of the sheath on the edge ring ER are mainly determined by the power level P _RF1 of the high frequency power RF1 and the power level P RF2 of the high frequency power _RF2 . be. In the plasma processing apparatus 1, the power level P during the first period T1 is reduced so as to reduce the difference between the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER during the first period T1. _RF1 or power level P _RF2 is set. The power level P _-RF1 and the power level P- _RF2 are designated by the control section 30 to the high frequency power source 31 and the high frequency power source 32, respectively.

In the plasma processing apparatus 1, the high frequency power supply 31, the high frequency power supply 32, the bias power supply 41, and the bias power supply 42 are synchronized with each other using a synchronization signal in order to adjust the power level _PRF1 and the power level _PRF2 within the period CY. It is The synchronization signal may be sent from one of the RF power supply 31, the RF power supply 32, the bias power supply 41, and the bias power supply 42 to the other power supply. Alternatively, the synchronization signal may be transmitted from the control section 30 to the high frequency power source 31 , the high frequency power source 32 , the bias power source 41 and the bias power source 42 . The synchronization signal may be generated by the controller 30 from the voltage of the electrical bias energy BE1 measured by the voltage sensor 41v or the voltage of the electrical bias energy BE2 measured by the voltage sensor 42v.

The first period T1 and the second period T2 are specified by the control unit 30 from the voltage of the electrical bias energy BE1 measured by the voltage sensor 41v or the voltage of the electrical bias energy BE2 measured by the voltage sensor 42v. good too. Alternatively, each of the first period T1 and the second period T2 may be set as a period within the cycle CY having a predetermined time length.

First to fourth examples of adjusting the power level P _-RF1 and the power level P- _RF2 in the period CY will be described below.

[First example]

In the first example, when the thickness TH _ER of the edge ring ER is greater than the predetermined value TH _P , the power level P _RF2 in the first period T1 is higher than the reference power level P _REF2 as shown in FIG. is also set to a lower power level. This reduces the difference between the position of the upper end _SHT1 of the sheath on the substrate W and the position of the upper end _SHT1 of the sheath on the edge ring ER, as indicated by the solid line in (a) of FIG. In addition, when the thickness TH _ER of the edge ring ER is larger than the predetermined value TH _P , the power level P - _{- RF2} in the second period T2 becomes a power level higher than the reference power level P - _{- REF2} , as shown in FIG. may be set. As a result, the reduced power level P- _RF2 in the first period T1 is compensated for in the second period T2, and the average plasma density in the cycle CY is maintained at a constant density.

[Second example]

In the second example, when the thickness TH _ER of the edge ring ER is greater than the predetermined value TH _P , the power level P _RF1 in the first period T1 is higher than the reference power level P _REF1 as shown in FIG. is also set to a high power level. This reduces the difference between the position of the upper end _SHT1 of the sheath on the substrate W and the position of the upper end _SHT1 of the sheath on the edge ring ER. In addition, when the thickness TH _ER of the edge ring ER is greater than the predetermined value TH _P , the power level P _RF1 in the second period T2 becomes a power level lower than the reference power level P _REF1 as shown in FIG. may be set. Thereby, the average power level _PRF1 in the period CY is maintained at a constant power level, and the average plasma density in the period CY is maintained at a constant density.

[Third example]

In the third example, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value TH _P , the power level P _RF2 in the first period T1 is lower than the reference power level P _REF2 as shown in FIG. is also set to a high power level. As a result, the difference between the position of the upper end _SHT1 of the sheath on the substrate W and the position of the upper end _SHT1 of the sheath on the edge ring ER is reduced, as indicated by the solid line in FIG. 5B. In addition, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value TH _P , the power level P _RF2 in the second period T2 becomes a power level lower than the reference power level P _REF2 as shown in FIG. may be set. Thereby, the average power level _PRF2 in the period CY is maintained at a constant power level, and the average plasma density in the period CY is maintained at a constant density.

[Fourth example]

In the fourth example, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value TH _P , the power level P _RF1 in the first period T1 is the reference power level P _REF1 as shown in FIG. set to a lower power level than This reduces the difference between the position of the upper end _SHT1 of the sheath on the substrate W and the position of the upper end _SHT1 of the sheath on the edge ring ER. In addition, when the thickness TH _ER of the edge ring ER is smaller than the predetermined value TH _P , the power level P _RF1 in the second period T2 becomes a power level higher than the reference power level P _REF1 as shown in FIG. may be set. As a result, the reduced power level _PRF1 in the first period T1 is compensated for in the second period T2, and the average plasma density in the cycle CY is maintained at a constant density.

In the plasma processing apparatus 1 described above, by adjusting the level of the second electrical bias energy, the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER during the second period within the period CY. It is possible to reduce the difference between In the first period T1, the power level P _RF1 of the high frequency power RF1 or the high frequency power RF2 is adjusted so as to reduce the difference between the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER. The power level P-- _RF2 of is set. Therefore, in the first period T1, it is possible to reduce the difference between the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER. Therefore, according to the plasma processing apparatus 1, the difference between the upper end position of the sheath on the substrate W and the upper end position of the sheath on the edge ring ER within the period CY of the electric bias energy BE2 supplied to the edge ring ER is can be reduced.

Plasma processing apparatuses according to some other exemplary embodiments will now be described with reference to FIGS. 6-14. FIG. 6 is a schematic diagram of a plasma processing apparatus according to another exemplary embodiment. Differences of the plasma processing apparatus 1B shown in FIG. 6 from the plasma processing apparatus 1 will be described below.

The plasma processing apparatus 1B has a base 111 instead of the first base 111a and the second base 111b. The base 111 has a substantially disk shape and is made of a conductor such as aluminum. The electrostatic chuck 113 is provided on the base 111 . In the plasma processing apparatus 1B, the high frequency power supply 31 and the bias power supply 41 are electrically connected to the base 111. As shown in FIG. The high frequency power supply 32 and the bias power supply 42 are electrically connected to the edge ring ER. Other configurations of the plasma processing apparatus 1B are the same as the corresponding configurations of the plasma processing apparatus 1B. Further, the operation of each part of the plasma processing apparatus 1B is the same as that of the corresponding part of the plasma processing apparatus 1B.

FIG. 7 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1C shown in FIG. 7 from the plasma processing apparatus 1B will be described below.

The plasma processing apparatus 1</b>C includes an insulating portion 115 that surrounds the base 111 . The insulating portion 115 is made of an insulator such as quartz. A peripheral portion of the edge ring ER is placed on the insulating portion 115 . An electrode 117 is provided in the insulating portion 115 . The electrode 117 may extend in the circumferential direction and may have an annular shape. The electrode 117 is arranged below the peripheral portion of the edge ring ER. In the plasma processing apparatus 1</b>C, the high frequency power supply 32 and the bias power supply 42 are electrically connected to the electrode 117 . Other configurations of the plasma processing apparatus 1C are the same as corresponding configurations of the plasma processing apparatus 1B. Also, the operation of each part of the plasma processing apparatus 1C is the same as that of the corresponding part of the plasma processing apparatus 1B.

FIG. 8 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1D shown in FIG. 8 from the plasma processing apparatus 1B will be described below.

In the plasma processing apparatus 1D, the electrode 113h is provided in the dielectric portion 113d of the electrostatic chuck 113 within the second region 11R2. The electrode 113h is a film made of a conductor. The electrode 113h may extend in the circumferential direction and may have a ring shape. The electrode 113h may be provided between each of the chuck electrodes 113b and 113c and the lower surface of the dielectric portion 113d. In the plasma processing apparatus 1D, the high frequency power supply 32 and the bias power supply 42 are electrically connected to the electrode 113h. Other configurations of the plasma processing apparatus 1D are the same as corresponding configurations of the plasma processing apparatus 1B. Also, the operation of each part of the plasma processing apparatus 1D is the same as that of the corresponding part of the plasma processing apparatus 1B.

FIG. 9 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1E shown in FIG. 9 from the plasma processing apparatus 1D will be described below.

In the plasma processing apparatus 1E, the electrode 113g is provided in the dielectric portion 113d of the electrostatic chuck 113 within the first region 11R1. The electrode 113g is a film made of a conductor. The electrode 113g may have a circular shape. The electrode 113g may be provided between the chuck electrode 113a and the lower surface of the dielectric portion 113d. In the plasma processing apparatus 1E, the high frequency power supply 31 and the bias power supply 41 are electrically connected to the electrode 113g. Other configurations of the plasma processing apparatus 1E are the same as corresponding configurations of the plasma processing apparatus 1D. Also, the operation of each part of the plasma processing apparatus 1E is the same as that of the corresponding part of the plasma processing apparatus 1D. In addition, in the plasma processing apparatus 1E, the base 111 may be made of any one of a conductor, a dielectric, and a semiconductor.

FIG. 10 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1F shown in FIG. 10 from the plasma processing apparatus 1E will be described below.

In the plasma processing apparatus 1F, the electrode 113n is provided in the dielectric portion 113d of the electrostatic chuck 113 within the second region 11R2. The electrode 113n is a film made of a conductor. The electrode 113n may extend in the circumferential direction and may have a ring shape. The electrode 113n may be provided between the electrode 113h and the lower surface of the dielectric portion 113d. In plasma processing apparatus 1F, high-frequency power supply 32 is electrically connected to electrode 113n. Other configurations of the plasma processing apparatus 1F are the same as corresponding configurations of the plasma processing apparatus 1E. Also, the operation of each part of the plasma processing apparatus 1F is the same as that of the corresponding part of the plasma processing apparatus 1E.

FIG. 11 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1G shown in FIG. 11 from the plasma processing apparatus 1F will be described below.

In the plasma processing apparatus 1G, the electrode 113m is provided in the dielectric portion 113d of the electrostatic chuck 113 within the first region 11R1. The electrode 113m is a film made of a conductor. The electrode 113m may have a circular shape. The electrode 113m may be provided between the electrode 113g and the lower surface of the dielectric portion 113d. In the plasma processing apparatus 1G, the high frequency power supply 31 is electrically connected to the electrode 113m. Other configurations of the plasma processing apparatus 1G are the same as corresponding configurations of the plasma processing apparatus 1F. Also, the operation of each part of the plasma processing apparatus 1G is the same as that of the corresponding part of the plasma processing apparatus 1F. In addition, in the plasma processing apparatus 1G, the base 111 may be made of any one of a conductor, a dielectric, and a semiconductor.

FIG. 12 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1H shown in FIG. 12 from the plasma processing apparatus 1E will be described below.

The plasma processing apparatus 1H does not have an electrode 113h. The high frequency power supply 32 and the bias power supply 42 are electrically connected to the base 111 . The plasma processing apparatus 1H uses the above-described second and fourth examples regarding the adjustment of the power level P- _RF1 and the power level P- _RF2 in the period CY. Other configurations of the plasma processing apparatus 1H are the same as corresponding configurations of the plasma processing apparatus 1E. Other operations of each part of the plasma processing apparatus 1H are the same as those of the corresponding parts of the plasma processing apparatus 1E.

FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1J shown in FIG. 13 from the plasma processing apparatus 1G will be described below.

The plasma processing apparatus 1J does not have the electrode 113n. The high frequency power supply 32 is electrically connected to the base 111 . The plasma processing apparatus 1J uses the above-described second and fourth examples regarding the adjustment of the power level P- _RF1 and the power level P- _RF2 in the cycle CY. Other configurations of the plasma processing apparatus 1J are the same as corresponding configurations of the plasma processing apparatus 1G. Other operations of each part of the plasma processing apparatus 1J are the same as those of the corresponding parts of the plasma processing apparatus 1G.

FIG. 14 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1K shown in FIG. 14 from the plasma processing apparatus 1 will be described below.

The plasma processing apparatus 1K does not include the high frequency power supply 32 and the bias power supply 42. FIG. In the plasma processing apparatus 1K, high frequency power generated by a single high frequency power supply 31 is branched to generate high frequency power RF1 and high frequency power RF2. The high frequency power RF1 is supplied to the first base 111a, and the high frequency power RF2 is supplied to the second base 111b.

The distribution ratio of the high frequency power generated by the single high frequency power supply 31 to the high frequency power RF1 and the high frequency power RF2 is adjusted by the adjuster 31a. In the plasma processing apparatus 1K, the power level P- _RF1 of the high-frequency power RF1 and the power level P- _RF2 of the high-frequency power RF2 are set by adjusting the distribution ratio by the adjuster 31a. Also in the plasma processing apparatuses 1B to 1K, the high frequency power generated by the single high frequency power supply 31 may be branched to generate the high frequency power RF1 and the high frequency power RF2.

As shown in FIG. 14, regulator 31a may be connected between a node on an electrical path connecting high-frequency power supply 31 to first base 111a and second base 111b. The regulator 31a may include circuitry with variable impedance. The circuit may consist of a parallel connection of a plurality of series circuits each containing a fixed capacitor and a switching element. Alternatively, the adjuster 31a may be an attenuator configured to attenuate the high frequency power supplied from the high frequency power supply 31 toward the second base 111b. Note that the coordinator 31a may be connected between the node and the first base 111a.

In the plasma processing apparatus 1K, the electrical bias energy generated by the single bias power supply 41 is branched to generate electrical bias energy BE1 and electrical bias energy BE2. Electrical bias energy BE1 is supplied to the first base 111a and electrical bias energy BE2 is supplied to the second base 111b.

The distribution ratio of the electrical bias energy generated by the single bias power supply 41 to the electrical bias energy BE1 and the electrical bias energy BE2 is adjusted by the adjuster 41a. In the plasma processing apparatus 1K, the level L _BE1 of the electrical bias energy BE1 and the level L _BE2 of the electrical bias energy BE1 are set by adjusting the distribution ratio by the adjuster 41a. Also in the plasma processing apparatuses 1B to 1K, the electrical bias energy generated by the single bias power supply 41 may be branched to generate the electrical bias energy BE1 and the electrical bias energy BE2.

As shown in FIG. 14, regulator 41a may be connected between a node on an electrical path connecting bias power supply 41 to first base 111a and second base 111b. The regulator 41a may include circuitry with variable impedance. The circuit may consist of a parallel connection of a plurality of series circuits each containing a fixed capacitor and a switching element. Alternatively, regulator 41a may be an attenuator configured to attenuate electrical bias energy supplied from bias power supply 41 toward second base 111b. Note that the adjuster 41a may be connected between the node and the first base 111a.

FIG. 15 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1L shown in FIG. 15 from the plasma processing apparatus 1 will be described below.

In the plasma processing apparatus 1L, the electrostatic chuck 113 includes a region 113e between its central portion and peripheral portion. Region 113 e may electrically separate the central portion and peripheral portion of electrostatic chuck 113 . Region 113e may be formed from an insulator. Alternatively, the region 113 e may be formed of a dielectric different from the material of the dielectric portion 113 d in the central portion of the electrostatic chuck 113 and the material of the dielectric portion 113 d in the peripheral portion of the electrostatic chuck 113 . Region 113e may be formed by thermal spraying. Alternatively, region 113e may be space. Further, in the plasma processing apparatus 1L, the central portion and the peripheral portion of the electrostatic chuck 113 may be made of different dielectrics. Note that in each of the plasma processing apparatuses according to the various exemplary embodiments described above, the electrostatic chuck 113 may also include a region 113e between its central portion and peripheral portion.

A plasma processing method according to one exemplary embodiment will now be described with reference to FIG. FIG. 16 is a flow diagram of a plasma processing method according to one exemplary embodiment. The plasma processing method shown in FIG. 16 (hereinafter referred to as "method MT") can be performed using the plasma processing apparatuses according to the various exemplary embodiments described above.

As shown in FIG. 16, method MT begins at step STa. In step STa, the substrate is placed on the substrate supporting portion 11 . Next, in method MT, process STb and process STc are performed in parallel. Gas is supplied from the gas supply unit 20 into the chamber 10 during the period during which the process STb and the process STc are performed. Moreover, during the period when the process STb and the process STc are performed, the pressure in the chamber 10 is reduced to a specified pressure by the exhaust system 40 .

In step STb, high-frequency power RF1 and high-frequency power RF2 are supplied to generate plasma from the gas in chamber 10 . In step STc, electrical bias energy BE1 is supplied to the substrate W and electrical bias energy BE2 is supplied to the edge ring ER. In method MT, in the first period T1, the power level P _RF1 of the high frequency power RF1 or the high frequency A power level P _RF2 of the power RF2 is set.

Also, the level L _BE2 of the electrical bias energy BE2 may be adjusted to reduce the difference between the top position of the sheath on the substrate W and the top position of the sheath on the edge ring ER within the period CY. Moreover, the power level P RF1 of the high frequency power _RF1 and/or the power level P RF2 of the high frequency power _RF2 can also be adjusted during the second period T2. For adjustment of the level L _BE2 of the electrical bias energy BE2 and adjustment of the power level P _RF1 of the high frequency power RF1 and/or the power level P RF2 of the high frequency power _RF2 , please refer to the above description of the plasma processing apparatus 1 .

While various exemplary embodiments have been described above, various additions, omissions, substitutions, and modifications may be made without being limited to the exemplary embodiments described above. Also, elements from different embodiments can be combined to form other embodiments.

Various exemplary embodiments included in the present disclosure will now be described in [E1] to [E16] below.

[E1]
a chamber;
a substrate support within the chamber and configured to support a substrate and an edge ring;
configured to generate at least a first RF power coupled to a plasma through the substrate and above the substrate and a second RF power coupled to the plasma through the edge ring and above the edge ring; a high frequency power source;
at least one bias power supply configured to generate a first electrical bias energy supplied to the substrate and a second electrical bias energy supplied to the edge ring;
with
the first electrical bias energy and the second electrical bias energy have waveforms that repeat with a period having a time length that is the reciprocal of the bias frequency;
The cycle includes a first period in which each voltage of the first electrical bias energy and the second electrical bias energy has a positive level with respect to an average value of the voltages in the cycle; a second period in which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level with respect to the average value;
In the first period, the power level of the first high-frequency power or the second high-frequency power is adjusted so as to reduce the difference between the upper end position of the sheath on the substrate and the upper end position of the sheath on the edge ring. the power level of the RF power is set,
Plasma processing equipment.

In the second period, the thickness of the sheath on the substrate and the thickness of the sheath on the edge ring are determined primarily by the level of the first electrical bias energy and the level of the second electrical bias energy. During the second time period, the level of the second electrical bias energy can be adjusted to reduce the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring. . On the other hand, the thickness of the sheath on the substrate and the thickness of the sheath on the edge ring are determined mainly by the power level of the first high frequency power and the power level of the second high frequency power in the first period. In the embodiment of [E1], in the first period, the power level of the first high frequency power or A power level of the second high frequency power is set. Therefore, in the first period, it is possible to reduce the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring. Therefore, according to the embodiment of [E1], the difference between the top position of the sheath on the substrate and the top position of the sheath on the edge ring is small within the period of the electrical bias energy supplied to the edge ring. becomes possible.

[E2]
The plasma processing apparatus of [E1], wherein the level of the second electrical bias energy is set to increase as the thickness of the edge ring decreases.

[E3]
The power level of the second high-frequency power supplied in the first period when the thickness of the edge ring is greater than the predetermined value is the same as the power level of the second high-frequency power when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E2], wherein the power level is set to be lower than the reference power level of the second high-frequency power to be set in one period.

[E4]
When the thickness of the edge ring is greater than the predetermined value, the power level of the second high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E3], wherein the power level is set higher than the reference power level of the second high-frequency power to be set in the second period.

[E5]
The power level of the first high-frequency power supplied in the first period when the thickness of the edge ring is greater than a predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E2], wherein the power level is set to be higher than the reference power level of the first high frequency power to be set in one period.

[E6]
The power level of the first high-frequency power supplied in the second period when the thickness of the edge ring is greater than the predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E5], wherein the power level is set lower than the reference power level of the first high frequency power to be set in the second period.

[E7]
The power level of the second high-frequency power supplied in the first period when the thickness of the edge ring is smaller than the predetermined value is the same as the power level of the second high-frequency power when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E2], wherein the power level is set to be higher than the reference power level of the second high-frequency power to be set in one period.

[E8]
When the thickness of the edge ring is less than the predetermined value, the power level of the second high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E7], wherein the power level is set lower than the reference power level of the second high-frequency power to be set in the second period.

[E9]
The power level of the first high-frequency power supplied in the first period when the thickness of the edge ring is smaller than a predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E2], wherein the power level is set to be lower than the reference power level of the first high-frequency power to be set in one period.

[E10]
When the thickness of the edge ring is less than the predetermined value, the power level of the first high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. The plasma processing apparatus according to [E9], wherein the power level is set higher than the reference power level of the first high-frequency power to be set in the second period.

[E11]
The at least one high-frequency power source includes a first high-frequency power source configured to generate the first high-frequency power and a second high-frequency power source configured to generate the second high-frequency power, The plasma processing apparatus according to any one of [E1] to [E10].

[E12]
A single high-frequency power supply is provided as the at least one high-frequency power supply,
further comprising an adjuster configured to adjust a distribution ratio of radio frequency power generated by the single radio frequency power supply to the first radio frequency power and the second radio frequency power;
The plasma processing apparatus according to any one of [E1] to [E10].

[E13]
said at least one bias power supply comprising a first bias power supply configured to generate said first electrical bias energy and a second bias power supply configured to generate said second electrical bias energy; The plasma processing apparatus according to any one of [E1] to [E12].

[E14]
A single bias power supply is provided as the at least one bias power supply,
further comprising an adjuster configured to adjust a distribution ratio of electrical bias energy generated by the single radio frequency power source to the first electrical bias energy and the second electrical bias energy [E1] The plasma processing apparatus according to any one of [E12].

[E15]
Each of the first electrical bias energy and the second electrical bias energy is radio frequency bias power or a pulse of voltage generated periodically at time intervals having a time length that is the reciprocal of the bias frequency. , the plasma processing apparatus according to any one of [E1] to [E14].

[E16]
placing a substrate on a substrate support in a chamber of a plasma processing apparatus, wherein an edge ring is mounted on the substrate support;
supplying a first RF power through the substrate to couple into a plasma above the substrate and a second RF power through the edge ring to couple into a plasma above the edge ring;
applying a first electrical bias energy to the substrate and a second electrical bias energy to the edge ring;
including
the first electrical bias energy and the second electrical bias energy have waveforms that repeat with a period having a time length that is the reciprocal of the bias frequency;
The cycle includes a first period in which each voltage of the first electrical bias energy and the second electrical bias energy has a positive level with respect to an average value of the voltages in the cycle; a second period in which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level with respect to the average value;
In the first period, the power level of the first high-frequency power or the second high-frequency power is adjusted so as to reduce the difference between the upper end position of the sheath on the substrate and the upper end position of the sheath on the edge ring. the power level of the RF power is set,
Plasma treatment method.

From the foregoing description, it will be appreciated that various embodiments of the present disclosure have been set forth herein for purposes of illustration, and that various changes may be made without departing from the scope and spirit of the present disclosure. Will. Therefore, the various embodiments disclosed herein are not intended to be limiting, with a true scope and spirit being indicated by the following claims.

DESCRIPTION OF SYMBOLS 1... Plasma processing apparatus, 10... Chamber, 11... Substrate support part, 31, 32... High frequency power supply, 41, 42... Bias power supply, W... Substrate, ER... Edge ring.

Claims (16)

a chamber;
a substrate support within the chamber and configured to support a substrate and an edge ring;
configured to generate at least a first RF power coupled to a plasma through the substrate and above the substrate and a second RF power coupled to the plasma through the edge ring and above the edge ring; a high frequency power source;
at least one bias power supply configured to generate a first electrical bias energy supplied to the substrate and a second electrical bias energy supplied to the edge ring;
with
the first electrical bias energy and the second electrical bias energy have waveforms that repeat with a period having a time length that is the reciprocal of the bias frequency;
The cycle includes a first period in which each voltage of the first electrical bias energy and the second electrical bias energy has a positive level with respect to an average value of the voltages in the cycle; a second period in which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level with respect to the average value;
In the first period, the power level of the first high-frequency power or the second high-frequency power is adjusted so as to reduce the difference between the upper end position of the sheath on the substrate and the upper end position of the sheath on the edge ring. the power level of the RF power is set,
Plasma processing equipment. 2. The plasma processing apparatus of claim 1, wherein the level of said second electrical bias energy is set to increase with decreasing thickness of said edge ring. The power level of the second high-frequency power supplied in the first period when the thickness of the edge ring is greater than the predetermined value is the same as the power level of the second high-frequency power when the thickness of the edge ring is the predetermined value. 3. The plasma processing apparatus according to claim 2, wherein the power level is set to be lower than the reference power level of said second high frequency power to be set in one period. When the thickness of the edge ring is greater than the predetermined value, the power level of the second high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. 4. The plasma processing apparatus according to claim 3, wherein the power level is set higher than the reference power level of said second high frequency power to be set in the second period. The power level of the first high-frequency power supplied in the first period when the thickness of the edge ring is greater than a predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. 3. The plasma processing apparatus according to claim 2, wherein the power level is set to be higher than the reference power level of said first high frequency power to be set in one period. The power level of the first high-frequency power supplied in the second period when the thickness of the edge ring is greater than the predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. 6. The plasma processing apparatus according to claim 5, wherein the power level is set lower than the reference power level of said first high frequency power to be set in the second period. The power level of the second high-frequency power supplied in the first period when the thickness of the edge ring is smaller than the predetermined value is the same as the power level of the second high-frequency power when the thickness of the edge ring is the predetermined value. 3. The plasma processing apparatus according to claim 2, wherein the power level is set to be higher than the reference power level of said second high frequency power to be set in one period. When the thickness of the edge ring is less than the predetermined value, the power level of the second high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. 8. The plasma processing apparatus according to claim 7, wherein the power level is set to be lower than the reference power level of said second high frequency power to be set in the second period. The power level of the first high-frequency power supplied in the first period when the thickness of the edge ring is smaller than a predetermined value is the same as the power level of the first high-frequency power when the thickness of the edge ring is the predetermined value. 3. The plasma processing apparatus according to claim 2, wherein the power level is set to be lower than the reference power level of said first high frequency power to be set in one period. When the thickness of the edge ring is less than the predetermined value, the power level of the first high-frequency power supplied in the second period is the same as when the thickness of the edge ring is the predetermined value. 10. The plasma processing apparatus according to claim 9, wherein the power level is set higher than the reference power level of said first high frequency power to be set in the second period. The at least one high-frequency power source includes a first high-frequency power source configured to generate the first high-frequency power and a second high-frequency power source configured to generate the second high-frequency power, The plasma processing apparatus according to any one of claims 1-10. A single high-frequency power supply is provided as the at least one high-frequency power supply,
further comprising an adjuster configured to adjust a distribution ratio of radio frequency power generated by the single radio frequency power supply to the first radio frequency power and the second radio frequency power;
The plasma processing apparatus according to any one of claims 1-10. said at least one bias power supply comprising a first bias power supply configured to generate said first electrical bias energy and a second bias power supply configured to generate said second electrical bias energy; The plasma processing apparatus according to any one of claims 1 to 10, comprising: A single bias power supply is provided as the at least one bias power supply,
10. Further comprising an adjuster configured to adjust the ratio of the electrical bias energy generated by the single radio frequency power source to the first electrical bias energy and the second electrical bias energy. 11. The plasma processing apparatus according to any one of items 1 to 10. Each of the first electrical bias energy and the second electrical bias energy is radio frequency bias power or a pulse of voltage generated periodically at time intervals having a time length that is the reciprocal of the bias frequency. The plasma processing apparatus according to any one of claims 1 to 10. placing a substrate on a substrate support in a chamber of a plasma processing apparatus, wherein an edge ring is mounted on the substrate support;
supplying a first RF power through the substrate to couple into a plasma above the substrate and a second RF power through the edge ring to couple into a plasma above the edge ring;
applying a first electrical bias energy to the substrate and a second electrical bias energy to the edge ring;
including
the first electrical bias energy and the second electrical bias energy have waveforms that repeat with a period having a time length that is the reciprocal of the bias frequency;
The cycle includes a first period in which each voltage of the first electrical bias energy and the second electrical bias energy has a positive level with respect to an average value of the voltages in the cycle; a second period in which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level with respect to the average value;
In the first period, the power level of the first high-frequency power or the second high-frequency power is adjusted so as to reduce the difference between the upper end position of the sheath on the substrate and the upper end position of the sheath on the edge ring. the power level of the RF power is set,
Plasma treatment method.

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