Plasma processing apparatus and plasma processing method

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

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Exemplary embodiments of the present disclosure relate to a plasma processing apparatus and a plasma processing method. [Background 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 is provided in the chamber. The substrate support supports a substrate and an edge ring (or a focus ring). The thickness of the edge ring is reduced by plasma processing. The following Patent Document 1 discloses a plasma processing apparatus configured to apply a negative DC voltage to the edge ring when the thickness of the edge ring is reduced. When the negative DC voltage is applied, the sheath on the edge ring becomes thicker, and 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 is eliminated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-227063 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides techniques for reducing the difference between the top end position of the sheath on the substrate and the top end position of the sheath on the edge ring within a period of electrical bias energy supplied to the edge ring. [Means for solving the problem]

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, at least one high frequency power source, and at least one bias power source. The substrate support is disposed within the chamber and configured to support a substrate and an edge ring. The at least one high frequency power source is configured to generate a first high frequency power that couples to a plasma above the substrate through the substrate and a second high frequency power that couples to a plasma above the edge ring through the edge ring. The at least one bias power source is configured to generate a first electrical bias energy that is provided to the substrate and a second electrical bias energy that is provided to the edge ring. The first electrical bias energy and the second electrical bias energy have a waveform that repeats with a bias period having a time length that is the inverse of a bias frequency. The bias period includes a first period and a second period. In the first period, a voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level with respect to an average value of the voltage in the bias period. In the second period, a 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 power level of the second high frequency power is set 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. Effect of the Invention

[0006] According to one exemplary embodiment, it is possible to reduce the difference between the top end position of the sheath on the substrate and the top end position of the sheath on the edge ring within a period of electrical bias energy supplied to the edge ring. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic diagram illustrating a plasma processing apparatus according to an exemplary embodiment; [Diagram 2] 1 is a schematic diagram illustrating a plasma processing apparatus according to an exemplary embodiment; [Diagram 3] 1 is a schematic diagram illustrating a plasma processing apparatus according to an exemplary embodiment; [Figure 4] 1 is a timing chart relating to a plasma processing apparatus according to an exemplary embodiment. [Diagram 5] Figure 5(a) is a diagram showing the upper end position of the sheath when the thickness of the edge ring is greater than a predetermined value, and Figure 5(b) is a diagram showing the upper end position of the sheath when the thickness of the edge ring is smaller than a predetermined value. [Figure 6] FIG. 13 is a schematic diagram of a plasma processing apparatus according to another exemplary embodiment. [Figure 7] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 8] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 9] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 10] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 11] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 12] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 13] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 14] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 15] FIG. 13 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. [Figure 16] 1 is a flow diagram of a plasma processing method according to an exemplary embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Various exemplary embodiments will now be described in detail with reference to the drawings, in which the same or corresponding parts are designated by the same reference numerals.

[0009] 1 and 2 are diagrams that illustrate a plasma processing apparatus according to an exemplary embodiment.

[0010] In one embodiment, the plasma processing system includes a plasma processing device 1 and a control unit 2. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support unit 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space, and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20, which will be described later, and the gas exhaust port is connected to an exhaust system 40, which will be described later. The substrate support unit 11 is disposed in the plasma processing space, and has a substrate support surface for supporting a substrate.

[0011] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma generated in the plasma processing space may be a capacitively coupled plasma (CCP), an inductively coupled plasma (ICP), an electron-cyclotron-resonance plasma (ECR plasma), a helicon wave plasma (HWP), a surface wave plasma (SWP), or the like.

[0012] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various steps described in the present disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform various steps described herein. In one embodiment, a part or all of the control unit 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. The processing unit 2a1 may be configured to perform various control operations based on a program stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0013] 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 unit 20, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas inlet includes a shower head 13. The substrate support 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support 11. In one embodiment, the shower head 13 constitutes at least a part of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The sidewall 10a is grounded. The shower head 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0014] The substrate support 11 is provided in the plasma processing chamber 10. The substrate support 11 is configured to support a substrate W and an 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. The substrate W is placed on the substrate support 11 and in a region surrounded by the edge ring ER. Although not shown, the substrate support 11 may include a temperature adjustment module configured to adjust at least one of the substrate W and the edge ring ER to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface.

[0015] The shower head 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple 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 10s from the multiple gas inlets 13c. The shower head 13 also includes a conductive member. The conductive member of the shower head 13 functions as an upper electrode. In addition to the shower head 13, the gas introduction unit may include one or more side gas injectors (SGI) attached to one or more openings formed in the side wall 10a.

[0016] The gas supply 20 may include one or more gas sources 21 and at least one or more flow controllers 22. In one embodiment, the gas supply 20 is configured to supply one or more process gases from respective gas sources 21 through respective flow controllers 22 to the showerhead 13. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply 20 may include one or more flow modulation devices to modulate or pulse the flow rate of one or more process gases.

[0017] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is adjusted by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0018] In the following, FIG. 3 will be referred to in addition to FIG. 2. FIG. 3 is a diagram that shows a schematic diagram of a plasma processing apparatus according to an exemplary embodiment. The substrate support 11 has a first base 111a, a second base 111b, and an electrostatic chuck 113. The first base 111a and the second base 111b are formed 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 on the radial outside of the first base 111a 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.

[0019] The electrostatic chuck 113 is provided on a first base 111a and a second base 111b. The substrate support 11 includes a first region 11R1 configured from a central portion of the electrostatic chuck 113 and the first base 111a. The substrate W is placed on the first region 11R1 and on the electrostatic chuck 113. The substrate support 11 includes a second region 11R2 configured from a 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.

[0020] The electrostatic chuck 113 has a dielectric portion 113d. The dielectric portion 113d is made of a dielectric material such as aluminum nitride or aluminum oxide. The dielectric portion 113d has a substantially disk shape. The first region 11R1 includes a central portion of the dielectric portion 113d. The second region 11R2 includes a peripheral portion of the dielectric portion 113d.

[0021] The electrostatic chuck 113 further includes a chuck electrode 113a. The chuck electrode 113a is a film made of a conductor and is provided in the dielectric portion 113d in the first region 11R1. A DC power supply 50p is electrically connected to the chuck electrode 113a via a switch 50s. When a DC voltage from the DC power supply 50p is applied to the chuck electrode 113a, an electrostatic attractive force is generated between the substrate W and the electrostatic chuck 113. The substrate W is attracted to the electrostatic chuck 113 by the generated electrostatic attractive force and is held by the electrostatic chuck 113.

[0022] The electrostatic chuck 113 may further include chuck electrodes 113b and 113c. Each of the chuck electrodes 113b and 113c is a film formed from a conductor. The chuck electrodes 113b and 113c may have a ring shape. The chuck electrodes 113b and 113c are provided in the dielectric portion 113d in the second region 11R2. The chuck electrode 113b is electrically connected to a DC power supply 51p via a switch 51s. The chuck electrode 113c is electrically connected to a DC power supply 52p via a switch 52s. When a DC voltage from the DC power supply 51p is applied to the chuck electrode 113b and a DC voltage from the DC power supply 52p is applied to the chuck electrode 113c, an electrostatic attraction force is generated between the edge ring ER and the electrostatic chuck 113. The edge ring ER is attracted to the electrostatic chuck 113 by the generated electrostatic force and is held by the electrostatic chuck 113.

[0023] 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).

[0024] The high frequency power supply 31 is configured to generate high frequency power RF1 (first high frequency power) to generate plasma in the chamber 10. The high frequency power RF1 has a frequency of, for example, 13 MHz or more and 150 MHz or less. The high frequency power RF1 is supplied to the substrate support 11 so as to couple to the plasma on the substrate W via the substrate support 11 and the substrate W. In the embodiment of FIG. 3, the high frequency power supply 31 is electrically connected to the first base 111a via a matching device 31m. The matching device 31m includes a matching circuit. The matching circuit of the matching device 31m has a variable impedance. The matching circuit of the matching device 31m is controlled by the control unit 30 described later. The impedance of the matching circuit of the matching device 31m is adjusted so as to match the impedance of the load side of the high frequency power supply 31 to the output impedance of the high frequency power supply 31.

[0025] The high frequency power supply 32 is configured to generate high frequency power RF2 (second high frequency power) to generate plasma in the chamber 10. The high frequency power RF2 has a frequency of, for example, 13 MHz or more and 150 MHz or less, similar to the high frequency power RF1. The high frequency power RF2 is supplied to the substrate support 11 so as to couple to the plasma on the edge ring ER via the substrate support 11 and 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 device 32m. The matching device 32m includes a matching circuit. The matching circuit of the matching device 32m has a variable impedance. The matching circuit of the matching device 32m is controlled by the control unit 30. The impedance of the matching circuit of the matching device 32m is adjusted so as to match the impedance of the load side of the high frequency power supply 32 to the output impedance of the high frequency power supply 32.

[0026] The bias power supply 41 is configured to generate an electric bias energy BE1 (first electric bias energy). The electric bias energy BE1 is supplied to the substrate W via the substrate support 11. The electric bias energy BE1 is supplied to the substrate W to adjust the energy of ions supplied from the plasma to the substrate W. In the embodiment of FIG. 3, the bias power supply 41 is electrically connected to the first base 111a.

[0027] The bias power supply 42 is configured to generate an electric bias energy BE2 (second electric bias energy). The electric bias energy BE2 is supplied to the edge ring ER via the substrate support 11. The electric bias energy BE2 is supplied to the edge ring ER to adjust the energy of 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.

[0028] FIG. 4 will be referred to below in conjunction with FIG. 2 and FIG. 3. FIG. 4 is a timing chart related to a plasma processing apparatus according to an exemplary embodiment. FIG. 4 shows the electric bias energy BE1 and the waveform (voltage waveform) of each of the electric bias energy BE1. FIG. 4 also shows the level L of the electric bias energy BE1. BE1 and the level L of the electrical bias energy BE2 BE2 FIG. 4 also shows the power level P RF1 and the power level P of the radio frequency power RF2 RF2 is shown.

[0029] Each of the electric bias energy BE1 and the electric bias energy BE2 has a waveform that repeats with a period CY (waveform period) having a time length that is the reciprocal of the bias frequency. The bias frequency is, for example, 100 kHz or more and 13.56 MHz or less.

[0030] In one embodiment, each of the electrical bias energy BE1 and the electrical bias energy BE2 may be a high frequency power having a bias frequency, i.e., a high frequency bias power LF. The high frequency bias power LF has a sinusoidal waveform in a period CY (waveform period), i.e., a bias period. The period CY has a time length that is the inverse of the bias frequency.

[0031] When the electric bias energy BE1 is a high frequency bias power LF, the bias power supply 41 is connected to the first base 111a via a matching device 41m. The matching device 41m includes a matching circuit. The matching circuit of the matching device 41m has a variable impedance. The matching circuit of the matching device 41m is controlled by the control unit 30. The impedance of the matching circuit of the matching device 41m is adjusted so as to match the impedance of the load side of the bias power supply 41 to the output impedance of the bias power supply 41.

[0032] When the electrical bias energy BE2 is high frequency bias power LF, the bias power supply 42 is connected to the second base 111b via a matching device 42m. The matching device 42m includes a matching circuit. The matching circuit of the matching device 42m has a variable impedance. The matching circuit of the matching device 42m is controlled by the control unit 30. The impedance of the matching circuit of the matching device 42m is adjusted so as to match the impedance of the load side of the bias power supply 42 to the output impedance of the bias power supply 42.

[0033] In another embodiment, each of the electric bias energy BE1 and the electric bias energy BE2 may be a voltage pulse PV that is periodically generated at a time interval (i.e., a period CY or a waveform period) having a time length that is the inverse of the bias frequency. The voltage pulse PV used as the electric bias energy BE1 and the electric bias energy BE2 may be a negative voltage pulse or a negative DC voltage pulse. The voltage pulse PV may have any waveform, such as a triangular wave or a rectangular wave. When a voltage pulse is used as the electric bias energy BE1, a filter may be connected to the bias power supply 41 instead of the matching device 41m so as to block the high frequency power. Also, when a voltage pulse is used as the electric bias energy BE2, a filter may be connected to the bias power supply 42 instead of the matching device 42m so as to block the high frequency power.

[0034] The cycle CY (waveform cycle) includes a first period T1 and a second period T2. In the first period T1, the voltages of the electrical bias energy BE1 and the electrical bias energy BE2 each have a positive level with respect to the average value of the voltages in the cycle CY. In the second period T2, the voltages of the electrical bias energy BE1 and the electrical bias energy BE2 each have a negative level with respect to the average value.

[0035] The high frequency power source 31 may change the frequency of the high frequency power RF1 within the cycle CY in order to suppress reflection of the high frequency power RF1 from the load. For this reason, the cycle CY is divided into a plurality of phase periods. The frequency of the high frequency power RF1 in each of the plurality of phase periods within the cycle CY is set using a time series of frequencies prepared in advance. The time series of frequencies can be specified to the high frequency power source 31 by the control unit 30.

[0036] Furthermore, the high frequency power source 32 may change the frequency of the high frequency power RF2 within the cycle CY in order to suppress reflection of the high frequency power RF2 from the load. The frequency of the high frequency power RF2 in each of the multiple phase periods within the cycle CY is set using a time series of frequencies prepared in advance. The time series of frequencies can be specified to the high frequency power source 32 by the control unit 30.

[0037] The control unit 30 is configured to control the high frequency power supply 31, the high frequency power supply 32, the bias power supply 41, and the bias power supply 42. The control unit 30 may be configured from a processor such as a CPU. The control unit 2 may also function as the control unit 30.

[0038] 5(a) and 5(b) will be referred to below along with Fig. 2 to Fig. 4. Fig. 5(a) is a diagram showing the position of the upper end of the sheath when the thickness of the edge ring is greater than a predetermined value, and Fig. 5(b) is a diagram showing the position of the upper end of the sheath when the thickness of the edge ring is smaller than a predetermined value.

[0039] As shown in (a) and (b) of FIG. 5, the thickness of the sheath is small in the first period T1, and the upper end SH of the sheath in the first period T1 is T1 On the other hand, in the second period T2, the thickness of the sheath is large, and the position of the upper end SH of the sheath in the second period T2 is T2 The position of the upper end of the sheath (i.e., the upper end position of the sheath) is the position in the height direction of the interface between the sheath and the plasma.

[0040] Edge ring thickness TH ER is the predetermined value TH PIn the case where, for example, the height position of the upper surface of the edge ring ER is equal to the height position of the upper surface of the substrate W, the upper end position of the sheath on the edge ring ER is equal to the upper end position of the sheath on the substrate W. Hereinafter, the level L of the electric bias energy BE2 in this case will be referred to as BE2 Reference level L REF2 In this case, the power level P of the high frequency power RF1 is RF1 The reference power level P REF1 In this case, the power level P of the high frequency power RF2 is RF2 The reference power level P REF2 He said.

[0041] Edge ring thickness TH ER is the predetermined value TH P Larger than level L BE2 is the reference level L REF2 5A, the upper end position of the sheath on the edge ring ER is higher than the upper end position of the sheath on the substrate W, as shown by the dashed line in FIG. ER is the predetermined value TH P Less than level L BE2 is the reference level L REF2 In this case, the position of the upper end of the sheath on the edge ring ER will be lower than the position of the upper end of the sheath on the substrate W, as indicated by the dashed line in FIG. 5(b).

[0042] In the plasma processing apparatus 1, 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, the level L of the electric bias energy BE2 is BE2 is adjusted. Also, the power level P RF1 and / or the power level P of the radio frequency power RF2 RF2 is adjusted. The level L of the electrical bias energy BE2 BE2 , and the power level P of the radio frequency power RF1 RF1 and the power level P of the radio frequency power RF2 RF2 can be controlled by the control unit 30.

[0043] 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 of the electrical bias energy BE1. BE1 and the level L of the electrical bias energy BE2 BE2 In the second period T2, the level L of the electrical bias energy BE2 is set to a value L in order to reduce the difference between the top end position of the sheath on the substrate W and the top end position of the sheath on the edge ring ER. BE2 is the thickness of the edge ring ER, TH ER The level L of the electrical bias energy BE2 is set to increase with the decrease of BE2 can be specified to the bias power supply 42 by the control unit 30.

[0044] Specifically, the thickness TH of the edge ring ER ER is the predetermined value TH P If the level is greater than the threshold, as shown in Figure 4, BE2 is the reference level L REF2 As a result, the upper end SH of the sheath on the substrate W is set at a level lower than that shown by the solid line in FIG. T2 Position of the sheath on the edge ring ER and the upper end SH T2 The difference in the position of the edge ring ER is reduced. ER may be obtained optically or electrically by a sensor. ER may be estimated from the length of time the edge ring ER is exposed to the plasma.

[0045] On the other hand, the thickness of the edge ring ER is ER is the predetermined value TH P If the level is smaller than the level L BE2 is the reference level L REF2 As a result, the upper end SH of the sheath on the substrate W is set at a level higher than that shown by the solid line in FIG. T2 Position of the sheath on the edge ring ER and the upper end SH T2 The difference in position is reduced.

[0046] In addition, the level L of the electrical bias energy BE1 BE1 The higher the level L of the electric bias energy BE2, the larger the absolute value of the negative bias potential of the substrate W, and the larger the thickness of the sheath on the substrate W. BE2 The higher the level, the larger the absolute value of the negative bias potential of the edge ring ER, and the larger the thickness of the sheath on the edge ring ER. If the electric 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 radio frequency bias power LF, then 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 with increasing negative voltage level of the voltage pulse PV. Also, if the electrical bias energy BE2 is the voltage pulse PV, the level L BE2 becomes higher as the voltage level of the voltage pulse PV increases in the negative direction.

[0047] 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 determined mainly by the power level P RF1 and the power level P of the radio frequency power RF2 RF2 In the plasma processing apparatus 1, the power level P in the first period T1 is set 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 in the first period T1. RF1 or power level P RF2 is set. Power level P RF1 and power level P RF2 are designated by the control unit 30 to the high frequency power sources 31 and 32, respectively.

[0048] In the plasma processing apparatus 1, the power level P RF1 and power level P RF2In order to adjust the power supply voltages, the RF power supply 31, the RF power supply 32, the bias power supply 41, and the bias power supply 42 are synchronized with each other using a synchronization signal. 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 supplies. Alternatively, the synchronization signal may be sent from the control unit 30 to the RF power supply 31, the RF power supply 32, the bias power supply 41, and the bias power supply 42. The synchronization signal may be generated 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.

[0049] The first period T1 and the second period T2 may be determined by the control unit 30 from the voltage of the electric bias energy BE1 measured by the voltage sensor 41v or the voltage of the electric bias energy BE2 measured by the voltage sensor 42v. Alternatively, each of the first period T1 and the second period T2 may be set as a period within a cycle CY having a predetermined time length.

[0050] Hereinafter, the power level P in the period CY RF1 and power level P RF2 First to fourth examples of the adjustment will be described.

[0051] [First example]

[0052] In the first example, the thickness TH of the edge ring ER ER is the predetermined value TH P If the power level P RF2 However, as shown in Figure 4, the reference power level P REF2 As a result, the power level of the upper end SH of the sheath above the substrate W is set to a lower level than that of the upper end SH of the sheath above the substrate W, as shown by the solid line in FIG. T1 Position of the sheath on the edge ring ER and the upper end SH T1 The difference in the position of the edge ring ER is reduced. ER is the predetermined value TH PIf the power level P in the second period T2 is greater than RF2 is the reference power level P REF2 This allows the power level P RF2 is supplemented in the second period T2 to maintain the average plasma density in the cycle CY at a constant density.

[0053] [Second example]

[0054] In the second example, the thickness TH of the edge ring ER ER is the predetermined value TH P If the power level P RF1 However, as shown in Figure 4, the reference power level P REF1 This causes the upper end SH of the sheath above the substrate W to T1 Position of the sheath on the edge ring ER and the upper end SH T1 The difference in the position of the edge ring ER is reduced. ER is the predetermined value TH P If the power level P in the second period T2 is greater than RF1 is the reference power level P REF1 This allows the average power level P RF1 is maintained at a constant power level, and the average plasma density during the period CY is maintained at a constant density.

[0055] [Third example]

[0056] In the third example, the thickness TH of the edge ring ER ER is the predetermined value TH P If the power level P RF2 However, as shown in Figure 4, the reference power level P REF2 As a result, the upper end SH of the sheath above the substrate W is set to a power level higher than that shown by the solid line in FIG. T1Position of the sheath on the edge ring ER and the upper end SH T1 The difference in the position of the edge ring ER is reduced. ER is the predetermined value TH P If the power level P in the second period T2 is smaller than RF2 is the reference power level P REF2 This allows the average power level P RF2 is maintained at a constant power level, and the average plasma density during the period CY is maintained at a constant density.

[0057] [Example 4]

[0058] In the fourth example, the thickness TH of the edge ring ER ER is the predetermined value TH P If the power level P RF1 is the reference power level P REF1 This causes the upper end SH of the sheath above the substrate W to T1 Position of the sheath on the edge ring ER and the upper end SH T1 The difference in the position of the edge ring ER is reduced. ER is the predetermined value TH P If the power level P in the second period T2 is smaller than RF1 is the reference power level P REF1 This allows the power level P RF1 is supplemented in the second period T2 to maintain the average plasma density in the cycle CY at a constant density.

[0059] In the plasma processing apparatus 1 described above, 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 in the second period in the cycle CY by adjusting the level of the second electric bias energy. Also, in the first period T1, the power level P of the radio frequency power RF1 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. RF1 Or the power level P of the high frequency power RF2 RF2 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, 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 within the period CY of the electric bias energy BE2 supplied to the edge ring ER.

[0060] Hereinafter, plasma processing apparatuses according to several other exemplary embodiments will be described with reference to Fig. 6 to Fig. 14. Fig. 6 is a diagram showing a schematic view of a plasma processing apparatus according to another exemplary embodiment. Hereinafter, differences between the plasma processing apparatus 1B shown in Fig. 6 and the plasma processing apparatus 1 will be described.

[0061] 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. The high frequency power supply 32 and the bias power supply 42 are electrically connected to the edge ring ER. The other configurations of the plasma processing apparatus 1B are the same as the corresponding configurations of the plasma processing apparatus 1. Moreover, the operation of each part of the plasma processing apparatus 1B is the same as the operation of the corresponding part of the plasma processing apparatus 1.

[0062] 7 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1C illustrated in FIG.

[0063] The plasma processing apparatus 1C includes an insulating part 115 provided to surround the base 111. The insulating part 115 is formed of an insulator such as quartz. The peripheral part of the edge ring ER is placed on the insulating part 115. An electrode 117 is provided in the insulating part 115. The electrode 117 may extend in the circumferential direction or may have a ring shape. The electrode 117 is disposed below the peripheral part of the edge ring ER. In the plasma processing apparatus 1C, 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 the corresponding configurations of the plasma processing apparatus 1B. Moreover, the operation of each part of the plasma processing apparatus 1C is the same as the operation of the corresponding part of the plasma processing apparatus 1B.

[0064] 8 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1D illustrated in FIG.

[0065] In the plasma processing apparatus 1D, an electrode 113h is provided in the dielectric portion 113d of the electrostatic chuck 113 in the second region 11R2. The electrode 113h is a film formed from a conductor. The electrode 113h may extend in the circumferential direction or 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 the corresponding configurations of the plasma processing apparatus 1B. Moreover, the operation of each part of the plasma processing apparatus 1D is the same as the operation of the corresponding part of the plasma processing apparatus 1B.

[0066] 9 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1E illustrated in FIG.

[0067] In the plasma processing apparatus 1E, an electrode 113g is provided in the dielectric portion 113d of the electrostatic chuck 113 in the first region 11R1. The electrode 113g is a film formed from 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. The other configurations of the plasma processing apparatus 1E are the same as the corresponding configurations of the plasma processing apparatus 1D. Moreover, the operation of each part of the plasma processing apparatus 1E is the same as the operation of the corresponding part of the plasma processing apparatus 1D. In the plasma processing apparatus 1E, the base 111 may be formed from any of a conductor, a dielectric, and a semiconductor.

[0068] 10 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1F illustrated in FIG.

[0069] In the plasma processing apparatus 1F, an electrode 113n is provided in the dielectric portion 113d of the electrostatic chuck 113 in the second region 11R2. The electrode 113n is a film formed from a conductor. The electrode 113n may extend in the circumferential direction or have a ring shape. The electrode 113n may be provided between the electrode 113h and the lower surface of the dielectric portion 113d. In the plasma processing apparatus 1F, the high-frequency power supply 32 is electrically connected to the electrode 113n. Other configurations of the plasma processing apparatus 1F are the same as the corresponding configurations of the plasma processing apparatus 1E. Moreover, the operation of each part of the plasma processing apparatus 1F is the same as the operation of the corresponding part of the plasma processing apparatus 1E.

[0070] 11 is a diagram illustrating a schematic configuration of a plasma processing apparatus according to still another embodiment of the present invention. Differences between the plasma processing apparatus 1G illustrated in FIG. 11 and the plasma processing apparatus 1F will be described below.

[0071] In the plasma processing apparatus 1G, the electrode 113m is provided in the dielectric portion 113d of the electrostatic chuck 113 in the first region 11R1. The electrode 113m is a film formed from 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. The other configurations of the plasma processing apparatus 1G are the same as the corresponding configurations of the plasma processing apparatus 1F. Moreover, the operation of each part of the plasma processing apparatus 1G is the same as the operation of the corresponding part of the plasma processing apparatus 1F. In the plasma processing apparatus 1G, the base 111 may be formed from any of a conductor, a dielectric, and a semiconductor.

[0072] 12 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1H illustrated in FIG.

[0073] 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. In the plasma processing apparatus 1H, the power level P RF1 and power level P RF2 The above-mentioned second and fourth examples regarding the adjustment are used. The other configurations of the plasma processing apparatus 1H are the same as the corresponding configurations of the plasma processing apparatus 1E. In addition, the other operations of each part of the plasma processing apparatus 1H are the same as the operations of the corresponding parts of the plasma processing apparatus 1E.

[0074] 13 is a diagram illustrating a schematic configuration of a plasma processing apparatus according to still another embodiment of the present invention. Differences between the plasma processing apparatus 1J illustrated in FIG. 13 and the plasma processing apparatus 1G will be described below.

[0075] The plasma processing apparatus 1J does not have an electrode 113n. The high frequency power supply 32 is electrically connected to the base 111. In the plasma processing apparatus 1J, the power level P RF1 and power level P RF2 The above-mentioned second and fourth examples regarding the adjustment are used. The other configurations of the plasma processing apparatus 1J are the same as the corresponding configurations of the plasma processing apparatus 1G. In addition, the other operations of each part of the plasma processing apparatus 1J are the same as the operations of the corresponding parts of the plasma processing apparatus 1G.

[0076] 14 is a diagram illustrating a plasma processing apparatus according to still another embodiment of the present invention, in which differences between the plasma processing apparatus 1K illustrated in FIG.

[0077] The plasma processing apparatus 1K does not include a high frequency power supply 32 and a bias power supply 42. 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 a first base 111a, and the high frequency power RF2 is supplied to a second base 111b.

[0078] 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 an adjuster 31a. In the plasma processing apparatus 1K, the power level P RF1 and the power level P of the radio frequency power RF2 RF2 is set by adjusting the distribution ratio by adjuster 31a. Note that in the plasma processing devices 1B to 1K as well, the high frequency power generated by single high frequency power supply 31 may be branched to generate high frequency power RF1 and high frequency power RF2.

[0079] As shown in FIG. 14, the adjuster 31a may be connected between a node on an electrical path connecting the high frequency power supply 31 to the first base 111a and the second base 111b. The adjuster 31a may include a circuit having a variable impedance. This circuit may be configured by a parallel connection of a plurality of series circuits, each of which includes a fixed capacitance 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 to the second base 111b. The adjuster 31a may be connected between the node and the first base 111a.

[0080] In the plasma processing apparatus 1K, the electric bias energy generated by the single bias power supply 41 is branched to generate the electric bias energy BE1 and the electric bias energy BE2. The electric bias energy BE1 is supplied to the first base 111a, and the electric bias energy BE2 is supplied to the second base 111b.

[0081] The distribution ratio of the electric bias energy BE1 and the electric bias energy BE2 generated by the single bias power supply 41 is adjusted by an adjuster 41a. In the plasma processing apparatus 1K, the level L of the electric bias energy BE1 is BE1 and the level L of the electrical bias energy BE1 BE2 is set by adjusting the distribution ratio by adjuster 41a. Note that in the plasma processing apparatuses 1B to 1K as well, the electric bias energy generated by the single bias power supply 41 may be branched to generate electric bias energy BE1 and electric bias energy BE2.

[0082] As shown in FIG. 14, the regulator 41a may be connected between a node on an electrical path connecting the bias power supply 41 to the first base 111a and the second base 111b. The regulator 41a may include a circuit having a variable impedance. This circuit may be composed of a parallel connection of a plurality of series circuits, each of which includes a fixed capacitance capacitor and a switching element. Alternatively, the regulator 41a may be an attenuator configured to attenuate the electrical bias energy supplied from the bias power supply 41 toward the second base 111b. The regulator 41a may be connected between the node and the first base 111a.

[0083] 15 is a diagram illustrating a schematic configuration of a plasma processing apparatus according to still another embodiment of the present invention. Differences between the plasma processing apparatus 1L illustrated in FIG. 15 and the plasma processing apparatus 1 will be described below.

[0084] In the plasma processing apparatus 1L, the electrostatic chuck 113 includes a region 113e between its central portion and its peripheral portion. The region 113e can electrically separate the central portion and the peripheral portion of the electrostatic chuck 113. The region 113e may be formed of an insulator. Alternatively, the region 113e may be formed of a dielectric material different from the material of the dielectric portion 113d in the central portion of the electrostatic chuck 113 and the material of the dielectric portion 113d in the peripheral portion of the electrostatic chuck 113. The region 113e may be formed by thermal spraying. Alternatively, the region 113e may be a space. In addition, in the plasma processing apparatus 1L, the central portion and the peripheral portion of the electrostatic chuck 113 may be formed of different dielectric materials. Note that, in each of the plasma processing apparatuses according to the various exemplary embodiments described above, the electrostatic chuck 113 may also include the region 113e between its central portion and its peripheral portion.

[0085] Hereinafter, a plasma processing method according to one exemplary embodiment will be described with reference to Fig. 16. Fig. 16 is a flow chart of the 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 apparatus according to the various exemplary embodiments described above.

[0086] 16, the method MT starts with step STa. In step STa, a substrate is placed on a substrate support 11. Next, in the method MT, steps STb and STc are performed in parallel. During the period in which steps STb and STc are performed, gas is supplied from the gas supply unit 20 into the chamber 10. Also, during the period in which steps STb and STc are performed, the pressure in the chamber 10 is reduced to a designated pressure by the exhaust system 40.

[0087] In step STb, high frequency powers RF1 and RF2 are supplied to generate plasma from the gas in the chamber 10. In step STc, electric bias energy BE1 is supplied to the substrate W, and electric bias energy BE2 is supplied to the edge ring ER. In the method MT, in a first period T1, the power level P of the high frequency power RF1 is adjusted 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. RF1 Or the power level P of the high frequency power RF2 RF2 is set.

[0088] In addition, in order to reduce the difference between the top end position of the sheath on the substrate W and the top end position of the sheath on the edge ring ER within the period CY, the level L of the electrical bias energy BE2 is BE2 Also, in the second period T2, the power level P RF1 and / or the power level P of the radio frequency power RF2 RF2 The level L of the electrical bias energy BE2 can be adjusted. BE2 is adjusted, and the power level P of the high frequency power RF1 is adjusted. RF1 and / or the power level P of the radio frequency power RF2 RF2 For the adjustment, please refer to the above description of the plasma processing apparatus 1.

[0089] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. In addition, elements in different embodiments can be combined to form other embodiments.

[0090] Various exemplary embodiments included in the present disclosure are now described in [E1] to [E16] below.

[0091] [E1] A chamber; a substrate support disposed within the chamber and configured to support a substrate and an edge ring; at least one RF power source configured to generate a first RF power that is coupled through the substrate to a plasma above the substrate and a second RF power that is coupled through the edge ring to a plasma above the edge ring; at least one bias power supply configured to generate a first electrical bias energy delivered to the substrate and a second electrical bias energy delivered to the edge ring; Equipped 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first 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. Plasma processing equipment.

[0092] In the second period, the thickness of the sheath on the substrate and the thickness of the sheath on the edge ring are mainly determined by the level of the first electric bias energy and the level of the second electric bias energy. In the second period, it is possible to reduce the difference between the top end position of the sheath on the substrate and the top end position of the sheath on the edge ring by adjusting the level of the second electric bias energy. On the other hand, the thickness of the sheath on the substrate and the thickness of the sheath on the edge ring are mainly determined 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], 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 end position of the sheath on the substrate and the top end position of the sheath on the edge ring in the first period. Therefore, it is possible to reduce the difference between the top end position of the sheath on the substrate and the top end position of the sheath on the edge ring in the first period. Therefore, according to the embodiment of [E1], it is possible to reduce the difference between the top end position of the sheath on the substrate and the top end position of the sheath on the edge ring within a period of electrical bias energy supplied to the edge ring.

[0093] [E2] The plasma processing apparatus according to [E1], wherein the level of the second electrical bias energy is set to increase in response to a decrease in the thickness of the edge ring.

[0094] [E3] The plasma processing apparatus described in [E2], wherein a power level of the second high frequency power supplied during the first period when the thickness of the edge ring is greater than a predetermined value is set to a power level lower than a reference power level of the second high frequency power that should be set during the first period when the thickness of the edge ring is the predetermined value.

[0095] [E4] The plasma processing apparatus described in [E3], wherein a power level of the second high frequency power supplied during the second period when the thickness of the edge ring is greater than the predetermined value is set to a power level higher than a reference power level of the second high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

[0096] [E5] The plasma processing apparatus described in [E2], wherein a power level of the first high frequency power supplied during the first period when the thickness of the edge ring is greater than a predetermined value is set to a power level higher than a reference power level of the first high frequency power that should be set during the first period when the thickness of the edge ring is the predetermined value.

[0097] [E6] The plasma processing apparatus described in [E5], wherein a power level of the first high frequency power supplied during the second period when the thickness of the edge ring is greater than the predetermined value is set to a power level lower than a reference power level of the first high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

[0098] [E7] The plasma processing apparatus described in [E2], wherein a power level of the second high frequency power supplied during the first period when the thickness of the edge ring is smaller than a predetermined value is set to a power level higher than a reference power level of the second high frequency power that should be set during the first period when the thickness of the edge ring is the predetermined value.

[0099] [E8] The plasma processing apparatus described in [E7], wherein a power level of the second high frequency power supplied during the second period when the thickness of the edge ring is smaller than the specified value is set to a power level lower than a reference power level of the second high frequency power that should be set during the second period when the thickness of the edge ring is the specified value.

[0100] [E9] The plasma processing apparatus described in [E2], wherein a power level of the first high frequency power supplied during the first period when the thickness of the edge ring is smaller than a predetermined value is set to a power level lower than a reference power level of the first high frequency power that should be set during the first period when the thickness of the edge ring is the predetermined value.

[0101] [E10] The plasma processing apparatus described in [E9], wherein a power level of the first high frequency power supplied during the second period when the thickness of the edge ring is smaller than the specified value is set to a power level higher than a reference power level of the first high frequency power that should be set during the second period when the thickness of the edge ring is the specified value.

[0102] [E11] The plasma processing apparatus according to any one of [E1] to [E10], comprising, as the at least one high frequency power supply, a first high frequency power supply configured to generate the first high frequency power and a second high frequency power supply configured to generate the second high frequency power.

[0103] [E12] The at least one high frequency power source includes a single high frequency power source, Further comprising an adjuster configured to adjust a distribution ratio of the high frequency power generated by the single high frequency power source to the first high frequency power and the second high frequency power. The plasma processing apparatus according to any one of [E1] to [E10].

[0104] [E13] The plasma processing apparatus according to any one of [E1] to [E12], comprising, as the at least one bias power supply, a first bias power supply configured to generate the first electrical bias energy and a second bias power supply configured to generate the second electrical bias energy.

[0105] [E14] The at least one bias power supply comprises a single bias power supply; The plasma processing apparatus according to any one of [E1] to [E12], further comprising an adjuster configured to adjust a distribution ratio of the electric bias energy generated by the single high frequency power supply to the first electric bias energy and the second electric bias energy.

[0106] [E15] The plasma processing apparatus according to any one of [E1] to [E14], wherein each of the first electrical bias energy and the second electrical bias energy is a high-frequency bias power or a voltage pulse generated periodically at a time interval having a time length of the inverse of the bias frequency.

[0107] [E16] placing a substrate on a substrate support in a chamber of a plasma processing apparatus, the substrate support having an edge ring mounted thereon; providing a first RF power that couples through the substrate to a plasma above the substrate and a second RF power that couples through the edge ring to a plasma above the edge ring; providing 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first 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. Plasma treatment method.

[0108] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0109] Reference Signs List 1: plasma processing apparatus, 10: chamber, 11: substrate support, 31, 32: high frequency power supplies, 41, 42: bias power supplies, W: substrate, ER: edge ring.

Claims

1. A chamber; a substrate support disposed within the chamber and configured to support a substrate and an edge ring; at least one RF power source configured to generate a first RF power that is coupled through the substrate to a plasma above the substrate and a second RF power that is coupled through the edge ring to a plasma above the edge ring; at least one bias power supply configured to generate a first electrical bias energy delivered to the substrate and a second electrical bias energy delivered to the edge ring; Equipped 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first period, a power level of the first radio frequency power or a power level of the second radio 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; the second electrical bias energy level is set to increase in response to a decrease in thickness of the edge ring; a power level of the second high frequency power supplied in the first period when the thickness of the edge ring is greater than a predetermined value is set to a power level lower than a reference power level of the second high frequency power that should be set in the first period when the thickness of the edge ring is the predetermined value. Plasma processing equipment.

2. 2. The plasma processing apparatus of claim 1, wherein a power level of the second high frequency power supplied during the second period when the thickness of the edge ring is greater than the predetermined value is set to a power level higher than a reference power level of the second high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

3. A chamber, a substrate support disposed within the chamber and configured to support a substrate and an edge ring; at least one RF power source configured to generate a first RF power that is coupled through the substrate to a plasma above the substrate and a second RF power that is coupled through the edge ring to a plasma above the edge ring; at least one bias power supply configured to generate a first electrical bias energy delivered to the substrate and a second electrical bias energy delivered to the edge ring; Equipped 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first period, a power level of the first radio frequency power or a power level of the second radio 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; the second electrical bias energy level is set to increase in response to a decrease in thickness of the edge ring; a 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 set to a power level higher than a reference power level of the first high frequency power that should be set in the first period when the thickness of the edge ring is the predetermined value; Plasma processing equipment.

4. 4. The plasma processing apparatus of claim 3, wherein a power level of the first high frequency power supplied during the second period when the thickness of the edge ring is greater than the predetermined value is set to a power level lower than a reference power level of the first high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

5. A chamber, a substrate support disposed within the chamber and configured to support a substrate and an edge ring; at least one RF power source configured to generate a first RF power that is coupled through the substrate to a plasma above the substrate and a second RF power that is coupled through the edge ring to a plasma above the edge ring; at least one bias power supply configured to generate a first electrical bias energy delivered to the substrate and a second electrical bias energy delivered to the edge ring; Equipped 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first period, a power level of the first radio frequency power or a power level of the second radio 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; the second electrical bias energy level is set to increase in response to a decrease in thickness of the edge ring; a power level of the second high frequency power supplied in the first period when the thickness of the edge ring is smaller than a predetermined value is set to a power level higher than a reference power level of the second high frequency power that should be set in the first period when the thickness of the edge ring is the predetermined value. Plasma processing equipment.

6. 6. The plasma processing apparatus of claim 5, wherein a power level of the second high frequency power supplied during the second period when the thickness of the edge ring is smaller than the predetermined value is set to a power level lower than a reference power level of the second high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

7. A chamber; a substrate support disposed within the chamber and configured to support a substrate and an edge ring; at least one RF power source configured to generate a first RF power that is coupled through the substrate to a plasma above the substrate and a second RF power that is coupled through the edge ring to a plasma above the edge ring; at least one bias power supply configured to generate a first electrical bias energy delivered to the substrate and a second electrical bias energy delivered to the edge ring; Equipped 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first period, a power level of the first radio frequency power or a power level of the second radio 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; the second electrical bias energy level is set to increase in response to a decrease in thickness of the edge ring; a 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 set to a power level lower than a reference power level of the first high frequency power that should be set in the first period when the thickness of the edge ring is the predetermined value; Plasma processing equipment.

8. 8. The plasma processing apparatus of claim 7, wherein a power level of the first high frequency power supplied during the second period when the thickness of the edge ring is smaller than the predetermined value is set to a power level higher than a reference power level of the first high frequency power that should be set during the second period when the thickness of the edge ring is the predetermined value.

9. 9. The plasma processing apparatus according to claim 1, comprising, as the at least one high frequency power supply, a first high frequency power supply configured to generate the first high frequency power and a second high frequency power supply configured to generate the second high frequency power.

10. The at least one high frequency power source includes a single high frequency power source, further comprising an adjuster configured to adjust a distribution ratio of the high frequency power generated by the single high frequency power source to the first high frequency power and the second high frequency power, The plasma processing apparatus according to any one of claims 1 to 8.

11. 9. The plasma processing apparatus according to claim 1, wherein the at least one bias power supply comprises a first bias power supply configured to generate the first electrical bias energy and a second bias power supply configured to generate the second electrical bias energy.

12. The at least one bias power supply comprises a single bias power supply; The plasma processing apparatus according to any one of claims 1 to 8, further comprising an adjuster configured to adjust a distribution ratio of the electrical bias energy generated by the single bias power supply to the first electrical bias energy and the second electrical bias energy.

13. 9. The plasma processing apparatus according to claim 1, wherein each of the first electrical bias energy and the second electrical bias energy is a high-frequency bias power or a voltage pulse generated periodically at a time interval having a time length equal to the inverse of the bias frequency.

14. placing a substrate on a substrate support in a chamber of a plasma processing apparatus, the substrate support having an edge ring mounted thereon; providing a first RF power that couples through the substrate to a plasma above the substrate and a second RF power that couples through the edge ring to a plasma above the edge ring; providing 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 inverse of a bias frequency; the cycle includes a first period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a positive level relative to an average value of the voltage within the cycle, and a second period during which the voltage of each of the first electrical bias energy and the second electrical bias energy has a negative level relative to the average value; during the first period, a power level of the first radio frequency power or a power level of the second radio 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; the second electrical bias energy level is set to increase in response to a decrease in thickness of the edge ring; a power level of the second high frequency power supplied in the first period when the thickness of the edge ring is greater than a predetermined value is set to a power level lower than a reference power level of the second high frequency power that should be set in the first period when the thickness of the edge ring is the predetermined value. Plasma treatment method.

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