Plasma processing equipment

Abstract

To provide a technique which suppresses the fluctuation of the spread in the radial direction of plasma in a cycle of electric bias energy supplied to a bias electrode of a substrate support unit of a plasma processing apparatus.SOLUTION: In the disclosed plasma processing apparatus, an edge ring is arranged so as to surround a substrate on a substrate support unit in a plasma processing chamber. A ring electrode is arranged so as to surround the edge ring. A first bias RF power source is configured to supply a first bias RF power to the bias electrode. The first bias RF power has a first frequency and a first power level. A second bias RF power source is configured to supply a second bias RF power to the ring electrode. The second bias RF power has the first frequency and a second power level and is synchronized with the first bias RF power.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a plasma processing apparatus and a plasma processing method.

Background Art

[0002] A plasma processing apparatus is used for plasma processing of a substrate. The plasma processing apparatus includes a chamber, an electrostatic chuck, and a lower electrode. The electrostatic chuck and the lower electrode are provided in the chamber. The electrostatic chuck is provided on the lower electrode. The electrostatic chuck supports an edge ring placed thereon. The edge ring may be called a focus ring. The electrostatic chuck supports a substrate disposed within a region surrounded by the edge ring. When plasma processing is performed in the plasma processing apparatus, a gas is supplied into the chamber. Also, high-frequency power is supplied to the lower electrode. Plasma is formed from the gas in the chamber. The substrate is processed by chemical species such as ions and radicals from the plasma.

[0003] When plasma processing is executed, the edge ring is consumed and the thickness of the edge ring becomes smaller. When the thickness of the edge ring becomes smaller, the position of the upper end of the plasma sheath (hereinafter referred to as "sheath") above the edge ring becomes lower. The position of the upper end of the sheat above the edge ring in the vertical direction should be equal to the position of the upper end of the sheat above the substrate in the vertical direction. Japanese Patent Application Laid-Open No. 2008-227063 (hereinafter referred to as "Patent Document 1") discloses a plasma processing apparatus capable of adjusting the position of the upper end of the sheat above the edge ring in the vertical direction. The plasma processing apparatus described in Patent Document 1 is configured to apply a DC voltage to the edge ring. Also, the plasma processing apparatus described in Patent Document 1 is configured to adjust the power level of the high-frequency power supplied to the lower electrode when a DC voltage is applied to the edge ring.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2008-227063 [Overview of the project] [Problems that the invention aims to solve]

[0005] This disclosure provides a technique for suppressing fluctuations in the radial spread of plasma within the period of the electrical bias energy supplied to the bias electrode of a substrate support of a plasma processing apparatus. [Means for solving the problem]

[0006] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus comprises a plasma processing chamber, a substrate support, an RF power supply, an edge ring, a ring electrode, a first bias RF power supply, and a second bias RF power supply. The substrate support is located within the plasma processing chamber and includes a bias electrode. The RF power supply is configured to generate RF power to generate plasma within the chamber. The edge ring is positioned to surround a substrate on the substrate support. The ring electrode is positioned to surround the edge ring. The first bias RF power supply is configured to supply a first bias RF power to the bias electrode. The first bias RF power has a first frequency and a first power level. The second bias RF power supply is configured to supply a second bias RF power to the ring electrode. The second bias RF power has a first frequency and a second power level. The second bias RF power is synchronized with the first bias RF power. [Effects of the Invention]

[0007] According to one exemplary embodiment, it is possible to suppress fluctuations in the radial spread of the plasma within the period of the electrical bias energy supplied to the bias electrode of the substrate support of the plasma processing apparatus. [Brief explanation of the drawing]

[0008] [Figure 1] This figure schematically shows a plasma processing apparatus according to one exemplary embodiment. [Figure 2] This figure shows a substrate support and multiple power supplies in a plasma processing apparatus according to one exemplary embodiment. [Figure 3] Figures 3(a) and 3(b) show examples of the electrical bias energy supplied to the bias electrode and the electrical bias energy supplied to the ring electrode, respectively. [Figure 4] This figure shows a substrate support and multiple power supplies according to another exemplary embodiment. [Figure 5] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 6] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 7] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 8] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 9] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 10] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 11] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 12] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 13] This figure shows a substrate support and multiple power supplies according to yet another exemplary embodiment. [Figure 14] This is a flowchart of a plasma processing method according to one exemplary embodiment. [Modes for carrying out the invention]

[0009] Hereinafter, various exemplary embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals.

[0010] FIG. 1 is a diagram schematically showing a plasma processing apparatus according to one exemplary embodiment. FIG. 2 is a diagram showing a substrate support and a plurality of power supplies of the plasma processing apparatus according to one exemplary embodiment. The plasma processing apparatus 1 shown in FIG. 1 is a capacitively coupled plasma processing apparatus. The plasma processing apparatus 1 includes a chamber 10 (plasma processing chamber). The chamber 10 provides an internal space 10s therein. The central axis of the internal space 10s is an axis AX extending in the vertical direction.

[0011] In one embodiment, the chamber 10 may include a chamber body 12. The chamber body 12 has a substantially cylindrical shape. The internal space 10s is provided inside the chamber body 12. The chamber body 12 is made of, for example, aluminum. The chamber body 12 is electrically grounded. A plasma-resistant film is formed on the inner wall surface of the chamber body 12, that is, the wall surface defining the internal space 10s. This film can be a ceramic film such as a film formed by an anodic oxidation process or a film formed from yttrium oxide.

[0012] The side wall of the chamber body 12 provides a passage 12p. The substrate W passes through the passage 12p when being transported between the internal space 10s and the outside of the chamber 10. A gate valve 12g is provided along the side wall of the chamber body 12 for opening and closing the passage 12p.

[0013] As shown in FIGS. 1 and 2, the plasma processing apparatus 1 further includes a substrate support 16. The substrate support 16 is surrounded by a dielectric part 7. The dielectric part 7 extends in the circumferential direction outside the substrate support 16 in the radial direction with respect to the axis AX. The dielectric part 7 is formed of a dielectric such as quartz. The dielectric part 7 may support the substrate support 16.

[0014] The substrate supporter 16 is configured to support the substrate W placed thereon in the chamber 10. The substrate W has a substantially disk shape. The substrate W is placed on the substrate supporter 16 such that its center is located on the axis AX. The substrate supporter 16 is further configured to support an edge ring ER. The edge ring ER has an annular shape. The edge ring ER is formed from a material selected according to the plasma treatment performed in the plasma processing apparatus 1. The edge ring ER is formed from, for example, silicon or silicon carbide. The edge ring ER is placed on the substrate supporter 16 such that its central axis coincides with the axis AX. The substrate W is disposed on the substrate supporter 16 and within the region surrounded by the edge ring ER. That is, the edge ring ER is disposed so as to surround the substrate W. Note that the outer edge portion of the edge ring ER may be placed on the dielectric portion 17.

[0015] The substrate supporter 16 may include a base 18 and an electrostatic chuck 20. The base 18 and the electrostatic chuck 20 are provided in the chamber 10. The base 18 is formed from a conductive material such as aluminum and has a substantially disk shape. The central axis of the base 18 is the axis AX.

[0016] The base 18 provides a flow path 18f therein. The flow path 18f is a flow path for a heat exchange medium. The heat exchange medium is, for example, a refrigerant. The flow path 18f is connected to a supply device 22 for the heat exchange medium. The supply device 22 is provided outside the chamber 10. The flow path 18f receives the heat exchange medium supplied from the supply device 22. The heat exchange medium supplied to the flow path 18f is returned to the supply device 22.

[0017] The electrostatic chuck 20 is provided on a base 18. The electrostatic chuck 20 may be fixed to the base 18 via a bonding member 19 such as an adhesive. The electrostatic chuck 20 includes a first region 20R1 and a second region 20R2. The first region 20R1 is a region that holds the substrate W placed on it and has a substantially disc shape. The central axis of the first region 20R1 substantially coincides with the axis AX. The second region 20R2 is a region that holds the edge ring ER placed on it. In plan view, the second region 20R2 has a substantially annular shape and extends radially outward from the first region 20R1 in the circumferential direction. The upper surface of the first region 20R1 extends at a position higher in the height direction than the upper surface of the second region 20R2 in the height direction.

[0018] The electrostatic chuck 20 has a body 20m and a chuck electrode 20a. The body 20m is made of a dielectric material such as aluminum oxide or aluminum nitride. The body 20m has a substantially disc shape. The central axis of the electrostatic chuck 20 and the body 20m is axis AX. The chuck electrode 20a is provided inside the body 20m in a first region 20R1. The chuck electrode 20a is a film made of a conductive material. The chuck electrode 20a may have a substantially circular planar shape. The center of the chuck electrode 20a may be located on axis AX. The chuck electrode 20a is electrically connected to a DC power supply 50p via a switch 50s. When a voltage from the DC power supply 50p is applied to the chuck electrode 20a, an electrostatic attraction force is generated between the electrostatic chuck 20 and the substrate W. Due to the generated electrostatic attraction force, the substrate W is attracted to the electrostatic chuck 20 and held by the electrostatic chuck 20.

[0019] The electrostatic chuck 20 may further have chuck electrodes 20b and 20c. The chuck electrodes 20b and 20c are provided within the body 20m in a second region 20R2. Each of the chuck electrodes 20b and 20c is a film formed from a conductive material. The chuck electrodes 20b and 20c extend circumferentially around the axis AX. The chuck electrode 20c extends radially outward relative to the chuck electrode 20b. Each of the chuck electrodes 20b and 20c may have an annular shape. The chuck electrode 20b is electrically connected to a DC power supply 51p via a switch 51s. The chuck electrode 20c is electrically connected to a DC power supply 52p via a switch 52s. When voltages from the DC power supply 51p and 52p are applied to the chuck electrodes 20b and 20c, respectively, an electrostatic attraction force is generated between the electrostatic chuck 20 and the edge ring ER. Due to the generated electrostatic attraction, the edge ring ER is attracted to the electrostatic chuck 20 and held by the electrostatic chuck 20.

[0020] The plasma processing apparatus 1 further comprises a ring electrode DR. The ring electrode DR extends radially outward from the edge ring ER. The ring electrode DR may have a substantially ring shape in plan view. In the embodiment of Figure 2, the ring electrode DR extends so as to surround the edge ring ER. The ring electrode DR may be disposed on the dielectric portion 17. In the embodiment of Figure 2, the ring electrode DR is formed from a conductive material such as silicon, silicon carbide, nickel, or Hastelloy.

[0021] As shown in Figure 1, the plasma processing apparatus 1 may provide a gas supply line 24. The gas supply line 24 supplies a heat transfer gas, such as He gas, from a gas supply mechanism into the gap between the upper surface of the electrostatic chuck 20 and the back surface (bottom surface) of the substrate W.

[0022] The plasma processing apparatus 1 further comprises an upper electrode 30. The upper electrode 30 is provided above the substrate support 16. The upper electrode 30, together with a member 32, closes the upper opening of the chamber body 12. The member 32 is insulating. The upper electrode 30 is supported on the upper part of the chamber body 12 via the member 32.

[0023] The upper electrode 30 may include a top plate 34 and a support 36. The lower surface of the top plate 34 defines an internal space 10s. The top plate 34 provides a plurality of gas holes 34a. Each of the plurality of gas holes 34a penetrates the top plate 34 in the direction of its thickness (vertical direction). The top plate 34 is formed from, for example, silicon. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is provided on the surface of an aluminum member. This film may be a ceramic film, such as a film formed by anodizing or a film formed from yttrium oxide.

[0024] The support 36 detachably supports the top plate 34. The support 36 is formed from a conductive material such as aluminum. The support 36 provides a gas diffusion chamber 36a within it. The support 36 further provides a plurality of gas holes 36b. The plurality of gas holes 36b extend downward from the gas diffusion chamber 36a and communicate with each of the plurality of gas holes 34a. The support 36 further provides a gas introduction port 36c. The gas introduction port 36c is connected to the gas diffusion chamber 36a. A gas supply pipe 38 is connected to the gas introduction port 36c.

[0025] A gas source group 40 is connected to the gas supply pipe 38 via a valve group 41, a flow controller group 42, and a valve group 43. The gas source group 40, valve group 41, flow controller group 42, and valve group 43 constitute a gas supply unit. The gas source group 40 includes multiple gas sources. Each of the valve group 41 and valve group 43 includes multiple valves (e.g., on / off valves). The flow controller group 42 includes multiple flow controllers. Each of the multiple flow controllers in the flow controller group 42 is a mass flow controller or a pressure-controlled flow controller. Each of the multiple gas sources in the gas source group 40 is connected to the gas supply pipe 38 via a corresponding valve in the valve group 41, a corresponding flow controller in the flow controller group 42, and a corresponding valve in the valve group 43. The plasma processing apparatus 1 is capable of supplying gas from one or more selected gas sources from the multiple gas sources of the gas source group 40 to the internal space 10s at individually adjusted flow rates.

[0026] The plasma processing apparatus 1 may further include a baffle member 48. The baffle member 48 extends between the dielectric portion 17 and the side wall of the chamber body 12. The baffle member 48 may be constructed, for example, by coating an aluminum member with a ceramic such as yttrium oxide. The baffle member 48 provides a plurality of through holes. The space above the baffle member 48 and the space below the baffle member 48 are connected through the plurality of through holes in the baffle member 48.

[0027] The plasma processing apparatus 1 may further include an exhaust system 50. The exhaust system 50 is connected to the bottom of the chamber body 12 via an exhaust pipe 52 below the baffle member 48. The exhaust system 50 has a pressure controller such as an automatic pressure control valve and a vacuum pump such as a turbomolecular pump, and can reduce the pressure in the internal space 10s.

[0028] As shown in Figures 1 and 2, the plasma processing apparatus 1 further comprises a high-frequency power supply 61 (RF power supply). The high-frequency power supply 61 generates high-frequency power RF (RF power) supplied to the high-frequency electrode to generate plasma above the substrate support 16. The high-frequency power RF has a frequency in the range of 27 to 100 MHz, for example, 40 MHz or 60 MHz. In one embodiment, the high-frequency electrode is a base 18. That is, in one embodiment, the base 18 provides a lower electrode which is the high-frequency electrode.

[0029] The high-frequency power supply 61 is connected to the base 18 via a matching circuit 61m. The matching circuit 61m has a matching circuit configured to match the impedance on the load side (base 18 side) of the high-frequency power supply 61 to the output impedance of the high-frequency power supply 61. In one embodiment, the high-frequency power supply 61 may be connected to the base 18 via the matching circuit 61m and a filter 61f. The filter 61f is a filter having a frequency characteristic that selectively passes high-frequency power RF and has the characteristic of blocking or reducing the electrical bias energy, which will be described later. The high-frequency power supply 61 may be electrically connected to the upper electrode 30 of the substrate support 16 instead of the high-frequency electrode. That is, in another embodiment, the high-frequency electrode may be the upper electrode 30.

[0030] The plasma processing apparatus 1 further includes a bias power supply 62 (first bias power supply). The bias power supply 62 is electrically coupled to the bias electrode of the substrate support 16 and is configured to generate electrical bias energy BE supplied to the bias electrode of the substrate support 16. In the embodiment shown in Figure 2, the bias electrode of the substrate support 16 is the base 18. The electrical bias energy BE is used to attract ions into the substrate W. The electrical bias energy BE has a bias frequency. The bias frequency may be different from or the same as the frequency of the high-frequency power RF. The bias frequency may be lower than the frequency of the high-frequency power RF. In one embodiment, the bias frequency is a frequency in the range of 50 kHz to 27 MHz, for example, 400 kHz.

[0031] Hereafter, Figures 1 and 2 will be discussed along with Figures 3(a) and 3(b). Figures 3(a) and 3(b) are examples of the electrical bias energy supplied to the bias electrode and the electrical bias energy supplied to the ring electrode, respectively.

[0032] In one embodiment, the bias power supply 62 (first bias power supply or first bias RF power supply) may generate high-frequency power, i.e., high-frequency bias power (first bias RF power), as electrical bias energy BE, as shown in Figure 3(a). The high-frequency bias power (and its voltage waveform) as electrical bias energy BE is a sine wave having a bias frequency. The reciprocal of the bias frequency is the time length of the period CP (repetition period).

[0033] The bias power supply 62 (first bias power supply or first bias RF power supply) is connected to the bias electrode (base 18 in the embodiment of Figure 2) via a matching circuit 62m and a filter 62f to supply high-frequency bias power to the bias electrode. The matching circuit 62m has a matching circuit configured to match the load-side impedance of the bias power supply 62 to the output impedance of the bias power supply 62. The filter 62f has a frequency characteristic that selectively passes electrical bias energy BE and has the characteristic of blocking or reducing high-frequency power RF.

[0034] In another embodiment, the bias power supply 62 (first bias power supply or first voltage pulse power supply) may be configured to periodically apply a voltage pulse as electrical bias energy BE to the bias electrode (base 18 in the embodiment of Figure 2), as shown in Figure 3(b). That is, the electrical bias energy BE may be a first DC pulse signal or a sequence of DC voltage pulses. The voltage pulse is applied to the bias electrode (base 18 in the embodiment of Figure 2) at time intervals (i.e., period CP) that are the reciprocal of the bias frequency. The voltage pulse may be a negative voltage pulse or a negative DC voltage pulse. The voltage pulse may have any waveform, such as a triangular wave or a square wave.

[0035] The plasma processing apparatus 1 may further include a high-frequency power supply 63 (RF power supply). The high-frequency power supply 63 generates high-frequency power RF2 (RF power) to generate plasma above the substrate support 16. The high-frequency power RF2 may have the same frequency as the high-frequency power RF. The high-frequency power supply 63 is electrically connected to the ring electrode DR via a matching circuit 63m and a filter 63f. The matching circuit 63m has a matching circuit configured to match the load-side impedance of the high-frequency power supply 63 to the output impedance of the high-frequency power supply 63. The filter 63f has the characteristic of selectively passing the high-frequency power RF2 and has the characteristic of blocking or reducing the electrical bias energy BE2, which will be described later.

[0036] The plasma processing apparatus 1 further includes a bias power supply 64 (second bias power supply). The bias power supply 64 is electrically coupled to the ring electrode DR and is configured to generate electrical bias energy BE2 supplied to the ring electrode DR. The electrical bias energy BE2 has the same bias frequency as the electrical bias energy BE.

[0037] As shown in Figure 3(a), the electrical bias energy BE2 may be high-frequency bias power (second bias RF power), similar to the electrical bias energy BE. In this case, the bias power supply 64 (second bias power supply or second bias RF power supply) is connected to the ring electrode DR via a matching circuit 64m and a filter 64f. The matching circuit 64m has a matching circuit configured to match the load-side impedance of the bias power supply 64 to the output impedance of the bias power supply 64. The filter 64f has a frequency characteristic that selectively passes the electrical bias energy BE2 and has the characteristic of blocking or reducing the high-frequency power RF2.

[0038] As shown in Figure 3(b), the electrical bias energy BE2 may be a sequence of voltage pulses, similar to the electrical bias energy BE. That is, the electrical bias energy BE2 generated by the bias power supply 64 (second bias power supply or second voltage pulse power supply) may be a second DC pulse signal or a sequence of DC voltage pulses. The voltage pulses of the electrical bias energy BE2 are applied periodically to the ring electrode DR at time intervals (i.e., period CP) that are the reciprocal of the bias frequency. The voltage pulses may be negative voltage pulses or negative DC voltage pulses. The voltage pulses may have any waveform, such as a triangular wave or a square wave.

[0039] As shown in Figures 3(a) and 3(b), one period (period CP or repeating period) of the electrical bias energy BE consists of a positive phase period PP (second period) and a negative phase period PN (first period). Similarly, one period (period CP or repeating period) of the electrical bias energy BE2 consists of a positive phase period PP (fourth period) and a negative phase period PN (third period). During the negative phase period PN, each of the electrical bias energy BE and BE2 has a voltage lower than its average voltage within one period (period CP). During the positive phase period PP, each of the electrical bias energy BE and BE2 has a voltage greater than or equal to its average voltage within one period (period CP).

[0040] The negative phase period PN of the electrical bias energy BE2 generated by the bias power supply 64 at least partially overlaps with the negative phase period PN of the electrical bias energy BE generated by the bias power supply 62. As shown in Figures 3(a) and 3(b), the negative phase period PN of the electrical bias energy BE2 may coincide with the negative phase period PN of the electrical bias energy BE. That is, the phase of the electrical bias energy BE2 may be synchronized with the phase of the electrical bias energy BE.

[0041] Furthermore, if the electrical bias energies BE and BE2 are the first and second bias RF powers, respectively, the first and second power levels of the first and second bias RF powers may be the same as or different from each other. The second power level may be greater than or less than the first power level.

[0042] If the electrical bias energy BE is a first voltage pulse signal, the first voltage pulse signal has a first voltage level in the first period and a second voltage level in the second period. The absolute value of the first voltage level is greater than the absolute value of the second voltage level. Also, if the electrical bias energy BE2 is a second voltage pulse signal, the second voltage pulse signal has a third voltage level in the third period and a second voltage level in the fourth period. The absolute value of the third voltage level is greater than the absolute value of the fourth voltage level. The first and third voltage levels may be negative. The third voltage level may be the same as the first voltage level, and the fourth voltage level may be the same as the second voltage level. Alternatively, the third voltage level may be different from the first voltage level.

[0043] If the electrical bias energies BE and BE2 are the first and second voltage pulse signals, respectively, the first period may have the same length as the second period. Alternatively, the first period may have a different length than the second period. The length of the first period may be longer or shorter than the length of the second period.

[0044] In one embodiment, the plasma processing apparatus 1 may further include a control unit MC. The control unit MC is a computer equipped with a processor, a memory device, an input device, a display device, etc., and controls each part of the plasma processing apparatus 1. Specifically, the control unit MC executes a control program stored in the memory device and controls each part of the plasma processing apparatus 1 based on recipe data stored in the memory device. Through the control by the control unit MC, the process specified by the recipe data is executed in the plasma processing apparatus 1.

[0045] During the positive phase period PP described above, the sheath thickness on the substrate W is small, and the impedance between the substrate W and the plasma is small, so a relatively large amount of high-frequency power RF is coupled to the plasma above the substrate W. On the other hand, during the negative phase period PN, the sheath thickness on the substrate W is large, and the impedance between the substrate W and the plasma is large. In the plasma processing apparatus 1, in the negative phase period PN, electrical bias energy BE2 is supplied to the ring electrode DR to increase the sheath thickness radially outside the edge of the substrate W and to increase the impedance between the ring electrode DR and the plasma. Therefore, high-frequency power RF coupled to the plasma above the ring electrode DR during the negative phase period PN is suppressed. As a result, fluctuations in the radial spread of the plasma within the period CP of the electrical bias energy BE supplied to the bias electrode are suppressed. Furthermore, it becomes possible to suppress abnormal shapes formed on and near the edge of the substrate W due to etching.

[0046] Refer to Figure 4 below. Figure 4 shows a substrate support and multiple power supplies according to another exemplary embodiment. The differences between the embodiment in Figure 4 and the embodiment in Figure 2 will be explained below.

[0047] The substrate support 16B in the embodiment shown in Figure 4 can be used as a substrate support for the plasma processing apparatus 1. In the embodiment shown in Figure 4, the ring electrode DRB extends radially outward from the edge ring ER. The ring electrode DRB may have a substantially ring shape in plan view. The ring electrode DRB extends so as to surround the edge ring ER and is positioned on the dielectric portion 17. The ring electrode DRB is formed from a conductive material such as silicon or silicon carbide.

[0048] In the substrate support 16B, the auxiliary electrode 71 is provided in the dielectric portion 17 below the ring electrode DRB. The auxiliary electrode 71 may have a ring shape and extend circumferentially around the axis AX. The other configurations of the substrate support 16B are the same as the corresponding configuration of the substrate support 16 shown in Figure 2. In the embodiment of Figure 4, the high-frequency power supply 63 and the bias power supply 64 are electrically connected to the auxiliary electrode 71 and capacitively coupled to the ring electrode DRB via the auxiliary electrode 71.

[0049] Refer to Figure 5 below. Figure 5 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 4 and the embodiment in Figure 3 will be explained below.

[0050] The substrate support 16C in the embodiment shown in Figure 5 can be used as a substrate support for the plasma processing apparatus 1. In the embodiment shown in Figure 5, the ring member 72 extends radially outward from the edge ring ER. The ring member 72 may have a substantially ring shape in plan view. The ring member 72 extends so as to surround the edge ring ER and is positioned on the dielectric portion 17. The ring member 72 is formed from a dielectric material such as quartz or aluminum oxide.

[0051] In the substrate support 16C, the ring electrode DRC is provided within the ring member 72. The ring electrode DRC may have a ring shape and extend circumferentially around the axis AX. Other configurations of the substrate support 16C are the same as the corresponding configuration of the substrate support 16B. In the embodiment shown in Figure 5, the high-frequency power supply 63 and the bias power supply 64 are electrically connected to the ring electrode DRC. The ring electrode DRC may be provided in a region away from the ring member 72, for example, within the dielectric portion 17.

[0052] Refer to Figure 6 below. Figure 6 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 6 and the embodiment in Figure 2 will be explained below.

[0053] In the embodiment shown in Figure 6, the plasma processing apparatus 1 further comprises a bias power supply 66. The bias power supply 66 is electrically coupled to the edge ring ER and is configured to generate electrical bias energy BE3 supplied to the edge ring ER. The electrical bias energy BE3 may have the same bias frequency as the electrical bias energy BE.

[0054] The electrical bias energy BE3 may also be high-frequency bias power (third bias RF power), similar to the electrical bias energy BE. In this case, the bias power supply 66 is connected to the edge ring ER via a matching circuit 66m and a filter 66f. The matching circuit 66m has a matching circuit configured to match the load-side impedance of the bias power supply 66 to the output impedance of the bias power supply 66 (third bias RF power supply). The filter 66f has a frequency characteristic that selectively passes the electrical bias energy BE3 and has the characteristic of blocking or reducing high-frequency power RF.

[0055] Alternatively, the electrical bias energy BE3 may be a sequence of voltage pulses or a third voltage pulse signal, similar to the electrical bias energy BE. The voltage pulses of the electrical bias energy BE3 are applied periodically to the ring electrode DR at time intervals (i.e., period CP) that are the reciprocal of the bias frequency.

[0056] According to the embodiment shown in Figure 6, the thickness of the sheath on the edge ring ER can be independently controlled by independently controlling the electrical bias energy supplied to the edge ring ER. In addition, the bias power supply 66 may also be electrically coupled to the edge ring ER in each of the substrate supporters 16B and 16C.

[0057] Refer to Figure 7 below. Figure 7 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 7 and the embodiment in Figure 6 will be explained below.

[0058] The substrate support 16D shown in Figure 7 can be used as a substrate support for the plasma processing apparatus 1. The electrostatic chuck 20D of the substrate support 16D further includes an electrode 20e. Other components of the substrate support 16D are the same as the corresponding components of the substrate support 16 shown in Figure 6. The electrode 20e is a film formed from a conductive material and is provided within the body 20m in a second region 20R2. The electrode 20e may have an annular shape or extend circumferentially around the axis AX. In the embodiment of Figure 7, the bias power supply 66 is electrically connected to the electrode 20e and capacitively coupled to the edge ring ER via the electrode 20e.

[0059] In addition, in each of the substrate supporters 16B and 16C, the bias power supply 66 may be electrically coupled to the edge ring ER via the electrode 20e. Furthermore, the bias power supply 66 may be electrically connected to the chuck electrode 20b and chuck electrode 20c. In this case, the substrate supporter does not need to include the electrode 20e.

[0060] Refer to Figure 8 below. Figure 8 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 8 and the embodiment in Figure 7 will be explained below.

[0061] The substrate support 16E shown in Figure 8 can be used as a substrate support for the plasma processing apparatus 1. The electrostatic chuck 20E of the substrate support 16E further includes an electrode 20f. Other components of the substrate support 16E are the same as the corresponding components of the substrate support 16D. The electrode 20f is a film formed from a conductive material and is provided within the main body 20m in the first region 20R1. The electrode 20f may have a substantially circular shape, and its center may be located on the axis AX. In the embodiment of Figure 8, the bias power supply 62 is electrically connected to the electrode 20f. That is, the electrode 20f constitutes a bias electrode in the substrate support 16E.

[0062] In addition, the bias power supply 62 may be electrically connected to the electrode 20f in both the substrate support 16B and the substrate support 16C. Alternatively, the bias power supply 62 may be electrically connected to the chuck electrode 20a. In this case, the chuck electrode 20a constitutes the bias electrode. In this case, the substrate support does not need to include the electrode 20f.

[0063] Refer to Figure 9 below. Figure 9 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 9 and the embodiment in Figure 8 will be explained below.

[0064] In the embodiment shown in Figure 9, the high-frequency power supply 61 and the bias power supply 62 are electrically connected to the electrode 20f. That is, the electrode 20f constitutes the high-frequency electrode and the bias electrode in the substrate support 16E.

[0065] Furthermore, in the embodiment shown in Figure 9, the plasma processing apparatus 1 further includes a high-frequency power supply 65. The high-frequency power supply 65 generates high-frequency power RF3 (RF power) to generate plasma above the substrate support 16. The high-frequency power RF3 may have the same frequency as the high-frequency power RF. The high-frequency power supply 65 is electrically connected to the electrode 20e via a matching circuit 65m and a filter 65f. The matching circuit 65m has a matching circuit configured to match the load-side impedance of the high-frequency power supply 65 to the output impedance of the high-frequency power supply 65. The filter 65f has the characteristic of selectively passing the high-frequency power RF3 and has the characteristic of blocking or reducing the electrical bias energy BE3.

[0066] Furthermore, in each of the substrate supporters 16B and 16C, the high-frequency power supply 61 and the bias power supply 62 may be electrically connected to the electrode 20f. Also, in each of the substrate supporters 16B and 16C, the high-frequency power supply 65 and the bias power supply 66 may be electrically connected to the electrode 20e.

[0067] Refer to Figure 10 below. Figure 10 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 10 and the embodiment in Figure 2 will be explained below.

[0068] In the embodiment shown in Figure 10, the plasma processing apparatus 1 does not include a high-frequency power supply 63 and a bias power supply 64. In the embodiment shown in Figure 10, the high-frequency power supply 61 is electrically connected to the ring electrode DR in addition to the high-frequency electrodes of the substrate support 16 (base 18 in the embodiment shown in Figure 10). In the embodiment shown in Figure 10, the high-frequency power RF is distributed to the high-frequency electrodes of the substrate support 16 and the ring electrode DR. The distribution ratio of the high-frequency power RF between the high-frequency electrodes of the substrate support 16 and the ring electrode DR is adjusted by an impedance adjuster 61i. The impedance adjuster 61i is connected between a node on the electrical path connecting the high-frequency power supply 61 and the high-frequency electrodes of the substrate support 16 and the ring electrode DR. The impedance adjuster 61i has a variable impedance. The impedance adjuster 61i may include, for example, a variable capacitance capacitor.

[0069] Furthermore, in the embodiment of Figure 10, the bias power supply 62 is electrically connected to the ring electrode DR in addition to the bias electrode of the substrate support 16 (base 18 in the embodiment of Figure 10). That is, in the embodiment of Figure 10, a single bias RF power supply 62 serves as both the first bias RF power supply and the second bias RF power supply. In the embodiment of Figure 10, the electrical bias energy BE is distributed to the bias electrode of the substrate support 16 and the ring electrode DR. The distribution ratio of the electrical bias energy BE between the bias electrode of the substrate support 16 and the ring electrode DR is adjusted by an impedance adjuster 62i. The impedance adjuster 62i is connected between a node on the electrical path connecting the bias power supply 62 and the bias electrode of the substrate support 16 and the ring electrode DR. The impedance adjuster 62i has a variable impedance. The impedance adjuster 62i may include, for example, a variable capacitance capacitor.

[0070] In the embodiment shown in Figure 10, electrical bias energy BE from a single bias power supply 62 is distributed to the bias electrode and ring electrode DR of the substrate support 16. Therefore, the phase of the electrical bias energy supplied to the bias electrode of the substrate support 16 and the phase of the electrical bias energy supplied to the ring electrode DR are synchronized with each other. Consequently, high-frequency power RF coupled to the plasma above the ring electrode DR during the negative phase period PN is suppressed. As a result, fluctuations in the radial spread of the plasma within the period of the electrical bias energy BE supplied to the bias electrode of the substrate support 16 are suppressed.

[0071] Furthermore, similar to the embodiment in Figure 10, in the substrate support 16B, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRB of the substrate support 16. Also, similar to the embodiment in Figure 10, in the substrate support 16B, the electrical bias energy BE from the bias power supply 62 may be distributed to the bias electrode and ring electrode DRB of the substrate support 16. Also, similar to the embodiment in Figure 10, in the substrate support 16C, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRC of the substrate support 16. Also, similar to the embodiment in Figure 10, in the substrate support 16C, the electrical bias energy BE from the bias power supply 62 may be distributed to the bias electrode and ring electrode DRC of the substrate support 16.

[0072] Refer to Figure 11 below. Figure 11 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 11 and the embodiment in Figure 10 will be described below.

[0073] In the embodiment shown in Figure 11, the plasma processing apparatus 1 includes a substrate support 16D. The substrate support 16D is identical to the substrate support 16D shown in Figure 7. In the embodiment shown in Figure 11, the bias power supply 62 is further electrically connected to the electrode 20e. In the embodiment of Figure 11, the electrical bias energy BE is distributed to the bias electrode, ring electrode DR, and electrode 20e of the substrate support 16. The distribution ratio of the electrical bias energy BE to the bias electrode, ring electrode DR, and electrode 20e of the substrate support 16 is adjusted by impedance adjusters 62i and 62j. The impedance adjuster 62j is connected between a node on the electrical path connecting the bias power supply 62 and the bias electrode of the substrate support 16 and the electrode 20e. The impedance adjuster 62j has a variable impedance. The impedance adjuster 62j may include, for example, a variable capacitance capacitor.

[0074] Furthermore, similar to the embodiment in Figure 11, in the substrate support 16B, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRB of the substrate support 16. Also, similar to the embodiment in Figure 11, in the substrate support 16B, the electrical bias energy BE from the bias power supply 62 may be distributed to the bias electrode, ring electrode DRB, and electrode 20e of the substrate support 16. Also, similar to the embodiment in Figure 11, in the substrate support 16C, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRC of the substrate support 16. Also, similar to the embodiment in Figure 11, in the substrate support 16C, the electrical bias energy BE from the bias power supply 62 may be distributed to the bias electrode, ring electrode DRC, and electrode 20e of the substrate support 16.

[0075] Refer to Figure 12 below. Figure 12 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 12 and the embodiment in Figure 11 will be described below.

[0076] In the embodiment shown in Figure 12, the plasma processing apparatus 1 is equipped with a substrate support 16E. The substrate support 16E is the same as the substrate support 16E shown in Figure 8. In the embodiment shown in Figure 12, the bias power supply 62 is electrically connected to the electrode 20f.

[0077] Furthermore, similar to the embodiment in Figure 12, in the substrate support 16B, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRB of the substrate support 16. Also, similar to the embodiment in Figure 12, in the substrate support 16B, the electrical bias energy BE from the bias power supply 62 may be distributed to the electrode 20f, ring electrode DRB, and electrode 20e. Also, similar to the embodiment in Figure 12, in the substrate support 16C, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the high-frequency electrode and ring electrode DRC of the substrate support 16. Also, similar to the embodiment in Figure 11, in the substrate support 16C, the electrical bias energy BE from the bias power supply 62 may be distributed to the electrode 20f, ring electrode DRC, and electrode 20e.

[0078] Refer to Figure 13 below. Figure 13 shows a substrate support and multiple power supplies according to yet another exemplary embodiment. The differences between the embodiment in Figure 13 and the embodiment in Figure 12 will be described below.

[0079] In the embodiment shown in Figure 13, the high-frequency power supply 61 is electrically connected to electrode 20f and further electrically connected to electrode 20e. In the embodiment of Figure 13, the high-frequency power RF is distributed to electrode 20f, ring electrode DR, and electrode 20e. The distribution ratio of the high-frequency power RF to electrode 20f, ring electrode DR, and electrode 20e is adjusted by impedance adjusters 61i and 61j. The impedance adjuster 61j is connected between a node on the electrical path connecting the high-frequency power supply 61 and electrode 20f and electrode 20e. The impedance adjuster 61j has a variable impedance. The impedance adjuster 61j may include, for example, a variable capacitance capacitor.

[0080] Furthermore, similar to the embodiment in Figure 13, in the substrate support 16B, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the electrode 20f, the ring electrode DRB, and the electrode 20e. Also, similar to the embodiment in Figure 13, in the substrate support 16B, the electrical bias energy BE from the bias power supply 62 may be distributed to the electrode 20f, the ring electrode DRB, and the electrode 20e. Also, similar to the embodiment in Figure 13, in the substrate support 16C, the high-frequency power RF from the high-frequency power supply 61 may be distributed to the electrode 20f, the ring electrode DRC, and the electrode 20e. Also, similar to the embodiment in Figure 13, in the substrate support 16C, the electrical bias energy BE from the bias power supply 62 may be distributed to the electrode 20f, the ring electrode DRC, and the electrode 20e.

[0081] Refer to Figure 14 below. Figure 14 is a flowchart of a plasma treatment method according to one exemplary embodiment. The plasma treatment method shown in Figure 14 (hereinafter referred to as "Method MT") can be performed using any of the various plasma treatment devices described above.

[0082] Method MT begins with step STa. In step STa, the substrate W is placed on the substrate support of the plasma processing apparatus 1. In step STa, the substrate W is positioned within the region enclosed by the edge ring ER. Method MT further includes steps STb to STd. Steps STb to STd are performed with the substrate W placed on the substrate support.

[0083] In step STb, high-frequency power RF is supplied to generate plasma above the substrate support. In plasma processing apparatus 1 equipped with a high-frequency power supply 63, high-frequency power RF2 may be supplied further. In plasma processing apparatus 1 equipped with a high-frequency power supply 65, high-frequency power RF3 may be supplied further. In method MT, steps STc and STd are performed during the period in which step STb is being performed, i.e., during the period in which plasma is being generated in the chamber 10.

[0084] In process STc, electrical bias energy BE is supplied to the bias electrode of the substrate support (base 18, electrode 20f, or chuck electrode 20a). In process STd, electrical bias energy (BE or BE2) is supplied to the ring electrode (DR, DRB, or DRC).

[0085] In step STd of one embodiment, electrical bias energy BE2 is supplied to the ring electrode. The negative phase period PN of the electrical bias energy BE2 at least partially overlaps with the negative phase period PN of the electrical bias energy BE supplied to the bias electrode of the substrate support. The negative phase period PN of the electrical bias energy BE2 may coincide with the negative phase period PN of the electrical bias energy BE supplied to the bias electrode of the substrate support. The phase of the electrical bias energy BE2 may be synchronized with the phase of the electrical bias energy BE supplied to the bias electrode of the substrate support.

[0086] In steps STc and STd of another embodiment, electrical bias energy BE from a single bias power supply 62 is distributed to the bias electrode and ring electrode of the substrate support. Therefore, the negative phase period PN of the electrical bias energy supplied to the ring electrode coincides with the negative phase period PN of the electrical bias energy supplied to the bias electrode of the substrate support. That is, the phase of the electrical bias energy supplied to the ring electrode coincides with the phase of the electrical bias energy supplied to the bias electrode of the substrate support.

[0087] Herein, various exemplary embodiments included in this disclosure are described in [E1] to [E12] and [F1] to [F19] below.

[0088] [E1] Chamber and, A substrate support is provided within the aforementioned chamber and is configured to support a substrate placed thereon and an edge ring placed thereon so as to surround the substrate, and includes a bias electrode. A high-frequency power supply configured to generate high-frequency power to generate plasma above the substrate support, A ring electrode extending radially outward from the edge ring, A first bias power supply electrically coupled to the bias electrode, A second bias power supply electrically coupled to the ring electrode, Equipped with, Each of the first bias power supply and the second bias power supply is configured to generate electrical bias energy having a bias frequency. One period of the electrical bias energy having a time length that is the reciprocal of the bias frequency includes a negative phase period in which the electrical bias energy has a voltage lower than its average voltage within that period. The negative phase period of the electrical bias energy generated by the second bias power supply overlaps at least partially with the negative phase period of the electrical bias energy generated by the first bias power supply. Plasma processing equipment.

[0089] One cycle of the electrical bias energy includes the negative phase period and the positive phase period described above. During the positive phase period, the electrical bias energy has a voltage greater than or equal to its average voltage within one cycle. During the positive phase period, the sheath thickness on the substrate is small, and the impedance between the substrate and the plasma is small, so a relatively large amount of high-frequency power is coupled to the plasma above the substrate. On the other hand, during the negative phase period, the sheath thickness on the substrate is large, and the impedance between the substrate and the plasma is large. In the above embodiment, in order to increase the sheath thickness radially outside the edge of the substrate during the negative phase period and to increase the impedance between the ring electrode and the plasma, electrical bias energy generated by a second bias power supply is supplied to the ring electrode. Therefore, the high-frequency power coupled to the plasma above the ring electrode during the negative phase period is suppressed. As a result, according to the above embodiment, fluctuations in the radial spread of the plasma within the cycle of the electrical bias energy supplied to the bias electrode are suppressed.

[0090] [E2] The plasma processing apparatus according to [E1], wherein the phase of the electrical bias energy generated by the second bias power supply is synchronized with the phase of the electrical bias energy generated by the first bias power supply.

[0091] [E3] The plasma processing apparatus according to [E1] or [E2], wherein the electrical bias energy generated by each of the first bias power supply and the second bias power supply is high-frequency power having the bias frequency, or pulses of voltage generated periodically at time intervals that are the reciprocal of the bias frequency.

[0092] [E4] A plasma processing apparatus according to any one of [E1] to [E3], wherein the first bias power supply, the second bias power supply, or another bias power supply that generates electrical bias energy having the bias frequency is electrically coupled to the edge ring.

[0093] [E5] Chamber and, A substrate support is provided within the aforementioned chamber and is configured to support a substrate placed thereon and an edge ring placed thereon so as to surround the substrate, and includes a bias electrode. A high-frequency power supply configured to generate high-frequency power to generate plasma above the substrate support, A ring electrode extending radially outward from the edge ring, A bias power supply is electrically coupled to the bias electrode and the ring electrode to generate electrical bias energy having a bias frequency and to distribute the electrical bias energy to the bias electrode and the ring electrode, A plasma processing device equipped with the following features.

[0094] In the above embodiment, electrical bias energy from a single bias power supply is distributed to the bias electrode and ring electrode of the substrate support. Therefore, the phase of the electrical bias energy supplied to the bias electrode of the substrate support and the phase of the electrical bias energy supplied to the ring electrode are synchronized with each other. Consequently, high-frequency power coupled to the plasma above the ring electrode during the negative phase period is suppressed. As a result, according to the above embodiment, fluctuations in the radial spread of the plasma within the period of electrical bias energy supplied to the bias electrode are suppressed.

[0095] [E6] The plasma processing apparatus according to [E5], wherein the electrical bias energy is either high-frequency power having the bias frequency or a pulse of voltage periodically generated at time intervals that are the reciprocal of the bias frequency.

[0096] [E7] The plasma processing apparatus according to [E5] or [E6], wherein the bias power supply or another bias power supply that generates electrical bias energy having the bias frequency is electrically coupled to the edge ring.

[0097] [E8] The plasma processing apparatus according to any one of [E1] to [E7], wherein the high-frequency power supply is electrically connected to the bias electrode or another electrode provided in the substrate support and is configured to supply the high-frequency power to the bias electrode or the other electrode.

[0098] [E9] A plasma processing apparatus according to any one of [E1] to [E8], wherein another high-frequency power supply configured to generate high-frequency power for generating plasma above the high-frequency power supply or the substrate support is electrically coupled to the ring electrode.

[0099] [E10] The ring electrode extends so as to surround the edge ring, the plasma processing apparatus according to any one of [E1] to [E9].

[0100] [E11] (a) A step of placing a substrate on a substrate support provided in the chamber of a plasma processing apparatus, wherein the substrate support includes a bias electrode, and the substrate is placed within a region surrounded by an edge ring placed on the substrate support, (b) A step of supplying high-frequency power to generate plasma above the substrate support, (c) A step of supplying electrical bias energy from a first bias power supply to the bias electrode, (d) A step of supplying electrical bias energy to a ring electrode from a second bias power supply, wherein the ring electrode extends radially outward from the edge ring, and the step is as follows: Includes, The electrical bias energy generated by the first bias power supply and the second bias power supply each has a bias frequency. Each period of the electrical bias energy generated by the first bias power supply and the second bias power supply has a time length that is the reciprocal of the bias frequency and includes a negative phase period in which the electrical bias energy has a voltage lower than its average voltage within that period. The negative phase period of the electrical bias energy generated by the second bias power supply overlaps at least partially with the negative phase period of the electrical bias energy generated by the first bias power supply. Plasma treatment method.

[0101] [E12] (a) A step of placing a substrate on a substrate support provided in the chamber of a plasma processing apparatus, wherein the substrate support includes a bias electrode, and the substrate is placed within a region surrounded by an edge ring placed on the substrate support, (b) A step of supplying high-frequency power to generate plasma above the substrate support, (c) A step of supplying electrical bias energy to the bias electrode, (d) A step of supplying electrical bias energy to a ring electrode, wherein the ring electrode extends radially outward from the edge ring, and the step of supplying electrical bias energy to the ring electrode, Includes, A plasma processing method in which, in (c) and (d) above, electrical bias energy generated by a single bias power supply is distributed to the bias electrode and the ring electrode.

[0102] [F1] Plasma processing chamber and A substrate support, including a bias electrode, is placed inside the plasma processing chamber. An RF power supply configured to generate RF power to generate plasma in the chamber, An edge ring is arranged to surround the substrate on the substrate support, A ring electrode is arranged to surround the edge ring, A first bias RF power supply configured to supply a first bias RF power to the bias electrode, wherein the first bias RF power has a first frequency and a first power level, and the first bias RF power supply and A second bias RF power supply configured to supply a second bias RF power to the ring electrode, wherein the second bias RF power has the first frequency and the second power level, and the second bias RF power is synchronized with the first bias RF power, and A plasma processing apparatus equipped with the following features.

[0103] [F2] The plasma processing apparatus according to [F1], wherein the second power level is the same as the first power level.

[0104] [F3] The plasma processing apparatus described in [F1], wherein the second power level is different from the first power level.

[0105] [F4] The plasma processing apparatus according to [F3], wherein the second power level is greater than the first power level.

[0106] [F5] The plasma processing apparatus according to [F3], wherein the second power level is smaller than the first power level.

[0107] [F6] A plasma processing apparatus according to any one of items [F1] to [F5], wherein a single bias RF power supply serves as both the first bias RF power supply and the second bias RF power supply.

[0108] [F7] Plasma processing chamber and A substrate support, including a bias electrode, is placed inside the plasma processing chamber. An RF power supply configured to generate RF power to generate plasma in the chamber, An edge ring is arranged to surround the substrate on the substrate support, A ring electrode is arranged to surround the edge ring, A first voltage pulse power supply configured to apply a first voltage pulse signal to the bias electrode, wherein the first voltage pulse signal has a first voltage level that is lower than a first average voltage of the first voltage pulse signal during a first period within the repetition period, and a second voltage level that is higher than the first average voltage during a second period within the repetition period, and the absolute value of the first voltage level is greater than the absolute value of the second voltage level, A second voltage pulse power supply configured to apply a second voltage pulse signal to the ring electrode, wherein the second voltage pulse signal has a third voltage level lower than the second average voltage of the second voltage pulse signal during the first period, and a fourth voltage level higher than the second average voltage during the second period, and the absolute value of the third voltage level is greater than the absolute value of the fourth voltage level, A plasma processing apparatus equipped with the following features.

[0109] [F8] The plasma processing apparatus according to [F7], wherein the first voltage level and the third voltage level have negative polarity.

[0110] [F9] The plasma processing apparatus according to [F7] or [F8], wherein the third voltage level is the same as the first voltage level, and the fourth voltage level is the same as the second voltage level.

[0111] [F10] The plasma processing apparatus according to [F9], wherein a single voltage pulse power supply serves as both the first voltage pulse power supply and the second voltage pulse power supply.

[0112] [F11] The plasma processing apparatus according to [F7] or [F8], wherein the third voltage level is different from the first voltage level.

[0113] [F12] A plasma processing apparatus according to any one of [F7] to [F11], wherein the first period has the same length as the second period.

[0114] [F13] A plasma processing apparatus according to any one of [F7] to [F11], wherein the first period has a length different from the length of the second period.

[0115] [F14] A plasma processing apparatus according to any one of [F7] to [F11], wherein the first period is longer than the length of the second period.

[0116] [F15] The plasma processing apparatus according to any one of [F7] to [F11], wherein the first period is shorter than the length of the second period.

[0117] [F16] Chamber and, A substrate support, including a bias electrode, is placed inside the chamber. An RF power supply configured to generate RF power to generate plasma in the chamber, An edge ring is arranged to surround the substrate on the substrate support, A ring electrode is arranged to surround the edge ring, A first bias power supply electrically connected to the bias electrode, A second bias power supply electrically connected to the ring electrode, Equipped with, Each of the first bias power supply and the second bias power supply is configured to generate electrical bias energy having a bias frequency. One period of the electrical bias energy having a time length that is the reciprocal of the bias frequency includes a negative phase period in which the electrical bias energy has a voltage lower than its average voltage within that period. The negative phase period of the electrical bias energy generated by the second bias power supply overlaps at least partially with the negative phase period of the electrical bias energy generated by the first bias power supply. Plasma processing equipment.

[0118] [F17] The plasma processing apparatus according to [F16], wherein the phase of the electrical bias energy generated by the second bias power supply is synchronized with the phase of the electrical bias energy generated by the first bias power supply.

[0119] [F18] The plasma processing apparatus according to [F16] or [F17], wherein the electrical bias energy generated by each of the first bias power supply and the second bias power supply is either RF power having the bias frequency or a sequence of DC voltage pulses periodically generated at time intervals that are the reciprocal of the bias frequency.

[0120] [F19] A plasma processing apparatus according to any one of [F16] to [F18], wherein the first bias power supply, the second bias power supply, or another bias power supply configured to generate electrical bias energy having the bias frequency is coupled to the edge ring.

[0121] Although various exemplary embodiments have been described above, the invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and modifications may be made. Furthermore, it is possible to combine elements from different embodiments to form other embodiments.

[0122] From the above description, it will be understood that the various embodiments of this disclosure are described herein for illustrative purposes and can be modified in various ways without departing from the scope and spirit of this disclosure. Accordingly, the various embodiments disclosed herein are not intended to limit the scope and spirit, and the true scope and spirit are shown by the appended claims. [Explanation of Symbols]

[0123] 1...Plasma processing apparatus, 10...Chamber, 16...Substrate support, 18...Base, 20...Electrostatic chuck, 61, 63...High-frequency power supply, 62, 64...Bias power supply, W...Substrate, ER...Edge ring, DR...Ring electrode.

Claims

1. Plasma processing chamber and A substrate support, including a bias electrode, is placed inside the plasma processing chamber. A first RF power supply configured to generate first RF power for generating plasma in the plasma processing chamber, A second RF power supply configured to generate a second RF power for generating plasma in the plasma processing chamber, An edge ring is arranged to surround the substrate on the substrate support, A ring electrode is arranged to surround the edge ring, A first bias RF power supply configured to supply a first bias RF power having a first frequency and a first power level to the bias electrode, A second bias RF power supply configured to supply a second bias RF power having the first frequency and second power level to the ring electrode, A third bias RF power supply configured to supply a third bias RF power to the edge ring, Equipped with, The first RF power is supplied to the high-frequency electrode or the bias electrode to generate plasma above the substrate support. The second bias RF power and the second RF power are applied to the ring electrode. The third bias RF power applied to the edge ring is different from the second bias RF power applied to the ring electrode. Plasma processing equipment.

2. The plasma processing apparatus according to claim 1, wherein the second power level is the same as the first power level.

3. The plasma processing apparatus according to claim 2, wherein a single bias RF power supply functions as both the first bias RF power supply and the second bias RF power supply.

4. The plasma processing apparatus according to claim 1, wherein the second power level is different from the first power level.

5. The plasma processing apparatus according to claim 4, wherein the second power level is greater than the first power level.

6. The plasma processing apparatus according to claim 4, wherein the second power level is smaller than the first power level.

7. The plasma processing apparatus according to claim 1, wherein the first bias RF power and the first RF power are different from the second bias RF power and the second RF power applied to the ring electrode.

8. The plasma processing apparatus according to claim 1, wherein the ring electrode is located on a dielectric component.

9. The plasma processing apparatus according to claim 1, wherein the ring electrode is directly connected to the second bias RF power supply and the second RF power supply.

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