TW202306440A - Plasma treatment device - Google Patents

Abstract

The disclosed plasma treatment device is provided with a chamber, a substrate support portion, a first high-frequency power source, and a second high-frequency power source. The substrate support portion includes first and second bases and first and second support regions. The first and second bases have conductivity. The second base is separate from the first base, and surrounds the outer periphery of the first base. The first support region is formed from a dielectric and provided above the first base, and supports a substrate mounted thereon. The second support region is formed from a dielectric and provided above the second base, and supports an edge ring mounted thereon. The first and second high-frequency power sources are configured to supply high-frequency power to the first and second bases, respectively.

Description

Plasma treatment device

An exemplary embodiment of the present invention relates to a plasma processing apparatus.

Plasma treatment equipment is used for plasma treatment of substrates. As one type of plasma processing apparatus, a capacitive coupling type plasma processing apparatus is known. A capacitively coupled plasma processing apparatus has a chamber, a substrate support, and a radio frequency power source. The substrate supporting part is arranged in the chamber to support the substrate and the edge ring. The radio frequency power supply supplies radio frequency power to generate plasma from the gas within the chamber. RF power is supplied to a base station such as a substrate support. Patent Document 1 below discloses such a plasma processing apparatus. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2020-96176

[Problem to be solved by the invention]

The present invention provides a technique capable of suppressing in-plane deviations in plasma treatment of substrates. [Means to solve the problem]

In an exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus has a chamber, a substrate support unit, a first radio frequency power source, and a second radio frequency power source. The substrate supporting part is arranged in the chamber. The substrate support unit includes a first base, a second base, a first support area, and a second support area. The first abutment and the second abutment are conductive. The second base and the first base are separated from each other and extend around the outer periphery of the first base. The first support area is formed by a dielectric body, is arranged above the first base, and supports the substrate placed thereon. The second support region is formed of a dielectric body, is provided above the second base, and supports the edge ring placed thereon. The first radio frequency power supply supplies radio frequency power for plasma generation to the first base station. The second RF power supply supplies RF power for plasma generation to the second base station. [Effect of Invention]

According to an exemplary embodiment, in-plane variation in plasma processing of a substrate can be suppressed.

[Mode for Carrying Out the Invention]

Hereinafter, various exemplary embodiments will be described.

In an exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus has a chamber, a substrate support unit, a first radio frequency power source, and a second radio frequency power source. The substrate supporting part is arranged in the chamber. The substrate support unit includes a first base, a second base, a first support area, and a second support area. The first abutment and the second abutment are conductive. The second base and the first base are separated from each other and extend around the outer periphery of the first base. The first support area is formed by a dielectric body, is arranged above the first base, and supports the substrate placed thereon. The second support region is formed of a dielectric body, is provided above the second base, and supports the edge ring placed thereon. The first radio frequency power supply supplies radio frequency power for plasma generation to the first base station. The second RF power supply supplies RF power for plasma generation to the second base station.

In the above embodiment, the radio frequency power from the first radio frequency power source is supplied to the plasma via the first base, the first support region, and the substrate. In addition, the radio frequency power from the second radio frequency power supply is supplied to the plasma via the second base station, the second support area and the edge ring. That is, the RF power supplied to the plasma on the substrate and the RF power supplied to the plasma on the edge ring can be individually adjusted. Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate and the radio frequency power per unit area supplied to the plasma on the edge ring can be reduced. Therefore, according to the above-described embodiment, in-plane variation in plasma processing of the substrate can be suppressed.

In an exemplary embodiment, the position of the top surface of the second base may be lower than the position of the top surface of the first base. The thickness of the second support region may be thinner than that of the first support region. The substrate supporting part may further include a dielectric part provided between the second supporting region and the second base and on the top surface of the second base. In this embodiment, the difference between the capacitance between the first base and the substrate and the capacitance between the second base and the edge ring can be reduced by the dielectric body.

In an exemplary embodiment, the dielectric part may be a ceramic thermal sprayed film formed on the top surface of the second base.

In an exemplary embodiment, the second supporting region may also be fixed to the second base by the bonding member and the dielectric body. The joining member is provided between the dielectric body part and the second support region, and fixes the second support region to the dielectric body part.

In an exemplary embodiment, the plasma processing device may further have a bias power supply and an adjustment power supply. The bias power supply supplies bias energy for introducing ions from the plasma to the substrate to the first base. Adjusting the power supply to apply voltage to the edge ring to adjust the position of the upper end of the plasma sheath in the height direction above the edge ring.

In an exemplary embodiment, a dielectric region for supplying a part of the bias energy from the first submount to the second submount may be provided between the first submount and the second submount.

In an exemplary embodiment, the plasma processing apparatus may further include a first bias power supply and a second bias power supply. The first bias power supply supplies bias energy for introducing ions from the plasma to the substrate to the first base. The second bias power supply supplies bias energy for introducing ions from the plasma to the edge ring to the second submount.

In an exemplary embodiment, the capacitance per unit area between the second base and the edge ring may be 0.8 times or more and 1.2 times or less the capacitance per unit area between the first base and the substrate.

In another exemplary embodiment, a plasma processing device is also provided. The plasma processing device has a chamber, a substrate supporting part, a radio frequency power source, and an impedance circuit. The substrate supporting part is arranged in the chamber. The substrate support unit includes a first base, a second base, a first support area, and a second support area. The first abutment and the second abutment are conductive. The second base and the first base are separated from each other and extend around the outer periphery of the first base. The first support area is formed by a dielectric body, is arranged above the first base, and supports the substrate placed thereon. The second support region is formed of a dielectric body, is provided above the second base, and supports the edge ring placed thereon. The radio frequency power supply generates radio frequency power for plasma generation. The impedance circuit is connected between the radio frequency power source and the first base station or the second base station.

In the above embodiment, the RF power supplied to the plasma on the substrate and the RF power supplied to the plasma on the edge ring can be adjusted by an impedance circuit. Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate and the radio frequency power per unit area supplied to the plasma on the edge ring can be reduced. Therefore, according to the above-described embodiment, in-plane variation in plasma processing of the substrate can be suppressed.

In an exemplary embodiment, the plasma processing apparatus may further include a first bias power supply and a second bias power supply. The first bias power supply supplies bias energy for introducing ions from the plasma to the substrate to the first base. The second bias power supply supplies bias energy for introducing ions from the plasma to the edge ring to the second submount.

In an exemplary embodiment, the plasma processing device may further include a bias power supply and another impedance circuit. A bias power supply generates bias energy for introducing ions from the plasma to the substrate and edge ring. The impedance circuit is connected between the bias power supply and the first base or the second base.

In an exemplary embodiment, the electrostatic capacitance per unit area between the radio frequency power supply and the edge ring may be more than 0.8 times and less than 1.2 times the electrostatic capacitance per unit area between the radio frequency power supply and the substrate.

In yet another exemplary embodiment, a plasma processing device is also provided. The plasma processing device has a chamber, a substrate supporting part, a radio frequency power supply and an adjustment power supply. The substrate supporting part is arranged in the chamber. The substrate supporting part includes a base, a first supporting area, and a second supporting area. The base has a first part and a second part extending in the circumferential direction outside the first part. The first supporting region is formed by a dielectric body, is arranged above the first part, and supports the substrate placed thereon. The second supporting region is formed of a dielectric body, is provided above the second part, and supports the edge ring placed thereon. The RF power supply supplies RF power for plasma generation to the base station. Adjusting the power supply to apply voltage to the edge ring to adjust the position of the upper end of the plasma sheath in the height direction above the edge ring. The position of the top surface of the second part is lower than the position of the top surface of the first part. The thickness of the second supporting region is thinner than that of the first supporting region. The substrate support part further includes a dielectric part disposed between the second support region and the second part and on the top surface of the second part.

Regulatory power can apply voltage to the edge ring through an electrical path that does not include the submount and the second support region.

In the above embodiment, the radio frequency power from the radio frequency power supply is supplied to the plasma via the first part, the first support region, and the substrate, and is supplied to the plasma via the second part, the second support region and the edge ring. In this embodiment, the difference between the capacitance between the first part and the substrate and the capacitance between the second part and the edge ring is reduced by the dielectric part. Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate and the radio frequency power per unit area supplied to the plasma on the edge ring can be reduced. Therefore, according to the above-described embodiment, in-plane variation in plasma processing of the substrate can be suppressed.

In an exemplary embodiment, the dielectric part may also be a thermally sprayed ceramic film formed on the top surface of the second part.

In an exemplary embodiment, the second supporting region may also be fixed to the second part by the bonding member and the dielectric body. The joining member is provided between the dielectric body part and the second support region, and fixes the second support region to the dielectric body part.

In an exemplary embodiment, the plasma processing device may further have a bias power supply. The bias power supplies the submount with bias energy for introducing ions from the plasma to the substrate and the edge ring.

In an exemplary embodiment, the capacitance per unit area between the second part and the edge ring may be 0.8 times or more and 1.2 times or less the capacitance per unit area between the first part and the substrate.

In the various exemplary embodiments described above, the first support region and the second support region may be individual electrostatic chucks separated from each other. Alternatively, the first supporting area and the second supporting area can also be integrated with each other to form a single electrostatic chuck.

Hereinafter, various exemplary embodiments will be described in detail with reference to the drawings. In addition, in each drawing, the same code|symbol is attached|subjected to the same or equivalent part.

FIG. 1 is a diagram schematically showing a plasma processing apparatus according to an exemplary embodiment. The plasma treatment device 1 shown in FIG. 1 has a chamber 10 . Fig. 2 is a diagram showing the structure in a chamber of a plasma processing apparatus according to an exemplary embodiment. As shown in FIG. 2 , the plasma processing device 1 may be a capacitively coupled plasma processing device.

The chamber 10 provides an internal space 10s therein. The central axis of the inner space 10s is the axis AX extending in the vertical direction. In one embodiment, the chamber 10 includes a chamber body 12 . The chamber body 12 has a roughly cylindrical shape. The inner space 10s is provided inside the chamber body 12 . The chamber body 12 is formed of, for example, aluminum. The chamber body 12 is electrically grounded. A plasma-resistant film is formed on the inner wall of the chamber body 12, that is, the wall defining the inner space 10s. This film may be a ceramic film such as a film formed by anodic oxidation or a film formed of yttrium oxide.

A passage 12p is formed on the side wall of the chamber body 12 . The substrate W passes through the passage 12p when being conveyed between the internal space 10s and the outside of the chamber 10 . To open and close the passage 12p, a gate valve 12g is provided along the side wall of the chamber body 12.

The plasma processing apparatus 1 further includes a substrate support unit 16 . The substrate support unit 16 supports the substrate W placed thereon inside the chamber 10 . The substrate W has a substantially disc shape. The substrate support unit 16 may also be supported by the support unit 17 . The support portion 17 extends upward from the bottom of the chamber body 12 . The support portion 17 has a substantially cylindrical shape. The support portion 17 is formed of an insulating material such as quartz.

The substrate supporting part 16 further supports the edge ring ER placed thereon. The edge ring ER is a roughly ring-shaped plate. The edge ring ER can also be conductive. The edge ring ER is formed of, for example, silicon or silicon carbide. The substrate W is placed on the substrate support portion 16 in the chamber 10 and in a region surrounded by the edge ring ER. The substrate W and the edge ER are mounted on the substrate support portion 16 such that their central axes coincide with the axis AX.

The plasma processing device 1 may further have an outer peripheral portion 28 and an outer peripheral portion 29 . The outer peripheral portion 28 extends upward from the bottom of the chamber body 12 . The outer peripheral portion 28 has a substantially cylindrical shape and extends along the outer periphery of the support portion 17 . The outer peripheral portion 28 is formed of a conductive material and has a substantially cylindrical shape. The peripheral portion 28 is electrically grounded. A film having plasma resistance is formed on the surface of the outer peripheral portion 28 . This film may be a ceramic film such as a film formed by anodic oxidation or a film formed of yttrium oxide.

The outer peripheral portion 29 is provided on the outer peripheral portion 28 . The outer peripheral portion 29 is formed of an insulating material. The outer peripheral portion 29 is formed of ceramics such as quartz. The outer peripheral portion 29 has a substantially cylindrical shape. The outer peripheral portion 29 extends along the outer periphery of the substrate support portion 16 .

The plasma processing device 1 further has an upper electrode 30 . The upper electrode 30 is provided above the substrate supporting portion 16 . The upper electrode 30 together with the member 32 closes the upper opening of the chamber body 12 . Member 32 is insulating. The upper electrode 30 is supported on the upper part of the chamber body 12 by the member 32 .

The upper electrode 30 may also include a top plate 34 and a support 36 . The bottom surface of the top plate 34 defines an internal space 10s. The top plate 34 provides a plurality of air holes 34a. A plurality of air holes 34a respectively penetrate the top plate 34 in the plate thickness direction (vertical direction). The plurality of air holes 34a open toward the internal space 10s. The top plate 34 is formed of, for example, silicon. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is provided on the surface of the aluminum member. This film may be a ceramic film such as a film formed by anodic oxidation or a film formed of yttrium oxide.

The support body 36 supports the top plate 34 in a detachable manner. The support body 36 is formed of a conductive material such as aluminum. The support body 36 provides a gas diffusion chamber 36a inside it. The support 36 further provides a plurality of pores 36b. A plurality of air holes 36b extend downward from the gas diffusion chamber 36a. The plurality of air holes 36b communicate with the plurality of air holes 34a respectively. The support body 36 further provides a gas inlet 36c. The gas introduction port 36c is connected to the gas diffusion chamber 36a. The gas supply pipe 38 is connected to the gas introduction port 36c.

The gas source group 40 is connected to the gas supply pipe 38 through a valve group 41 , a flow controller group 42 , and a valve group 43 . The gas source group 40, the valve group 41, the flow controller group 42, and the valve group 43 constitute a gas supply unit. The gas source group 40 includes a plurality of gas sources. The valve group 41 and the valve group 43 each include a plurality of valves (for example, switching valves). The flow controller group 42 includes a plurality of flow controllers. The plurality of flow controllers in the flow controller group 42 are mass flow controllers or pressure-controlled flow controllers. The plurality of gas sources of the gas source group 40 are respectively connected to the gas supply pipe 38 through the corresponding valves of the valve group 41 , the corresponding flow controllers of the flow controller group 42 , and the corresponding valve groups of the valve group 43 . The plasma processing apparatus 1 can supply the gas from one or more gas sources selected from the plurality of gas sources in the gas source group 40 to the internal space 10s at an individually adjusted flow rate.

A baffle 48 is disposed between the outer peripheral portion 28 and the sidewall of the chamber body 12 . The baffle 48 may be constructed by, for example, an aluminum member coated with a ceramic such as yttrium oxide. A plurality of through holes are formed in the baffle plate 48 . Below the baffle 48 , an exhaust pipe 52 is connected to the bottom of the chamber body 12 . The exhaust device 50 is connected to the exhaust pipe 52 . The exhaust device 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.

In one embodiment, the plasma processing apparatus 1 may further include a control unit MC. The control unit MC is a computer having 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 the control program stored in the memory device, and controls each part of the plasma processing apparatus 1 according to the recipe data recorded in the memory device. Under the control of the control unit MC, the program specified by the recipe data is executed in the plasma processing device 1 .

Hereinafter, the board|substrate support part 16 is demonstrated in detail. As shown in FIG. 1 , the substrate support unit 16 includes a first base 181 , a second base 182 , a first support area 201 , and a second support area 202 .

The first base 181 and the second base 182 are conductive. The first base 181 and the second base 182 may also be formed of a conductive material such as aluminum. The first base 181 has a substantially disc shape. The central axis of the first base 181 approximately coincides with the axis AX. The second base 182 is separated from the first base 181 and extends to surround the outer periphery of the first base 181 . The second base 182 may have a substantially ring shape in plan view. The central axis of the second abutment 182 approximately coincides with the axis AX. The position in the height direction of the top surface of the second base 182 may be lower than the position in the height direction of the top surface of the first base 181 .

The first support region 201 is formed of a dielectric. The first supporting area 201 is set above the first base 181 . The first support region 201 supports the substrate W placed thereon. The first supporting region 201 may also be fixed on the top surface of the first base 181 by a bonding member 191 such as an adhesive.

The first supporting area 201 may also include a main body 201m and a chuck electrode 201a. The body 201m is formed of a dielectric such as alumina, aluminum nitride. The main body 201m is roughly disc-shaped. The central axis of the main body 201m is approximately coincident with the axis AX.

The chuck electrode 201a is disposed inside the body 201m. The chuck electrode 201a may be a film formed of a conductive material. The chuck electrode 201a may have a substantially circular planar shape. The center of the chuck electrode 201a is located on the axis AX. The chuck electrode 201a is connected to a DC power source 51p through a switch 51s. When a DC voltage from the DC power supply 51p is applied to the chuck electrode 201a, an electrostatic attraction force is generated between the first support region 201 and the substrate W. The substrate W is attracted to the first support region 201 by the generated electrostatic attraction, and is held by the first support region 201 .

The second support region 202 is formed of a dielectric. The second support area 202 is provided above the second base 182 . The second support area 202 supports the edge ring ER placed thereon. The second supporting region 202 may also be fixed to the top surface of the second base 182 or the top surface of the dielectric body portion 22 described later by a bonding member 192 such as an adhesive.

The second support region 202 may also include a body 202m, a chuck electrode 202a, and a chuck electrode 202b. The body 202m is formed of a dielectric such as alumina, aluminum nitride. The main body 202m extends in the circumferential direction to surround the first supporting area 201 . The body 202m may be approximately annular. The central axis of the main body 202m is approximately coincident with the axis AX.

The chuck electrodes 202a and 202b are disposed inside the body 202m. Each of the chuck electrodes 202a and 202b may be a film formed of a conductive material. The chuck electrodes 202a and 202b extend circumferentially around the axis AX. The chuck electrode 202b extends outside the chuck electrode 202a. The chuck electrodes 202a and 202b may be approximately ring-shaped. The respective centers of the chuck electrodes 202a and 202b are located on the axis AX. The chuck electrode 202a is connected to a DC power source 521p through a switch 521s. The chuck electrode 202b is connected to a DC power source 522p through a switch 522s. When the DC voltages from the DC power sources 521p and 522p are applied to the chuck electrodes 202a and 202b, electrostatic attraction is generated between the second support region 202 and the edge ring ER. The edge ring ER is attracted to the second support region 202 by the generated electrostatic attraction, and is held by the second support region 202 .

The plasma processing apparatus 1 further has a first radio frequency power source 61 and a second radio frequency power source 62 . The first radio frequency power supply 61 supplies radio frequency power for plasma generation to the first base station 181 . The first radio frequency power supply 61 is electrically connected to the first base station 181 through a matching device 61m. The radio frequency power generated by the first radio frequency power supply 61 has a frequency in the range of 27-100 MHz, for example, 40 MHz or 60 MHz. The matching unit 61m has a matching circuit for matching the impedance of the load of the first radio frequency power supply 61 with the output impedance of the first radio frequency power supply 61 .

The second RF power supply 62 supplies RF power for plasma generation to the second base station 182 . The second radio frequency power supply 62 is electrically connected to the second base station 182 through a matching device 62m. The radio frequency power generated by the second radio frequency power source 62 may have the same frequency as that of the radio frequency power generated by the first radio frequency power source 61 . The matching unit 62m has a matching circuit for matching the impedance of the load of the second radio frequency power supply 62 with the output impedance of the second radio frequency power supply 62 .

In the plasma processing apparatus 1 , a radio frequency electric field is generated in the chamber 10 by the radio frequency power from the first radio frequency power source 61 and the radio frequency power from the second radio frequency power source 62 . The gas in the chamber 10 is excited by the generated radio frequency electric field. As a result, plasma is generated within the chamber 10 . The substrate W is treated with chemical species such as ions and/or free radicals from the generated plasma. For example, the substrate W is etched with chemical species from a plasma.

The plasma processing device 1 may further have a bias power supply 71 . The bias power supply 71 is electrically connected to the first base 181 . The bias power supply 71 generates bias energy for introducing ions into the substrate W. As shown in FIG. The bias energy has a bias frequency. The bias frequency can be a frequency in the range of 50kHz~13.56MHz.

In one embodiment, the bias energy can also be radio frequency bias power with a bias frequency. In this embodiment, the bias power supply 71 is electrically connected to the first base 181 through a matcher 71m. The matching unit 71 m has a matching circuit for matching the impedance of the load of the bias power supply 71 and the output impedance of the bias power supply 71 .

In another embodiment, the bias energy can also be a pulse of voltage. A voltage pulse is periodically generated at a time interval (that is, a bias cycle) that is the inverse of the bias frequency, and is applied to the first base 181 . The pulse of the voltage can also be in any waveform like a rectangular wave or a triangular wave.

In the plasma processing apparatus 1 , RF power from the first RF power source 61 is supplied to the plasma via the first base 181 , the first support region 201 , and the substrate W. In addition, the radio frequency power from the second radio frequency power source 62 is supplied to the plasma via the second base station 182, the second support region 202, and the edge ring ER. That is, in the plasma processing apparatus 1 , the RF power supplied to the plasma on the substrate W and the RF power supplied to the plasma on the edge ring ER can be individually adjusted. Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate W and the radio frequency power per unit area supplied to the plasma on the edge ring can be reduced. Therefore, according to the plasma processing apparatus 1 , in-plane variation of the plasma processing on the substrate W can be suppressed.

As shown in FIG. 1 , in one embodiment, the position of the top surface of the second base 182 may be lower than the position of the top surface of the first base 181 . The thickness of the second supporting region 202 may also be thinner than that of the first supporting region 201 . The substrate supporting portion 16 may further include a dielectric portion 22 . The dielectric part 22 is provided between the second support region 202 and the second base 182 and on the top surface of the second base 182 . The dielectric body portion 22 is formed of a dielectric body such as alumina or aluminum nitride. The dielectric part 22 may also be a thermally sprayed ceramic film formed on the top surface of the second base 182 . In this embodiment, the difference between the capacitance between the first base 181 and the substrate W and the capacitance between the second base 182 and the edge ring ER is reduced by the dielectric part 22 .

In one embodiment, the plasma processing apparatus 1 may further include an adjustable power supply 80 . The adjustment power supply 80 applies a voltage to the edge ring ER to adjust the height direction position of the upper end of the plasma sheath above the edge ring ER.

In one embodiment, the dielectric region 24 may also be disposed between the first base 181 and the second base 182 . The dielectric body region 24 is formed of a dielectric body. The dielectric region 24 is provided to supply part of the bias energy from the first submount 181 to the second submount 182 . That is, the first base 181 and the second base 182 are capacitively coupled via the dielectric region 24 .

In one embodiment, the capacitance per unit area between the second base 182 and the edge ring ER may be 0.8 times or more or 1.2 times the capacitance per unit area between the first base 181 and the substrate W. the following. According to this embodiment, the difference between the radio frequency power per unit area supplied to the plasma on the substrate W and the radio frequency power per unit area supplied to the plasma on the edge ring can be further reduced.

In addition, in the example shown in FIG. 1 , the first support region 201 and the second support region 202 are separate electrostatic chucks separated from each other. However, the first support area 201 and the second support area 202 can also be integrated with each other, and can also form a single electrostatic chuck.

Hereinafter, refer to FIG. 3 . Fig. 3 is a diagram schematically showing a plasma processing apparatus according to another exemplary embodiment. The difference between the plasma processing apparatus 1B shown in FIG. 3 and the plasma processing apparatus 1 will be described below.

The plasma processing apparatus 1B further has a bias power supply 72 . The bias power supply 72 (second bias power supply) generates the same bias energy as that generated by the bias power supply 71 (first bias power supply). The bias power supply 72 is electrically connected to the second base 182 . When the bias energy generated by the bias power supply 72 is used as the RF bias power, the bias power supply 72 is electrically connected to the second base station 182 through the matching device 72m. The matching unit 72m has a matching circuit for matching the impedance of the load of the bias power supply 72 and the output impedance of the bias power supply 72 .

In the substrate support portion 16B of the plasma processing apparatus 1B, the dielectric region 24B is provided between the first base 181 and the second base 182 . The dielectric region 24B has a relatively small capacitance in the respective frequency bands of radio frequency power and bias energy, so as to electrically separate the first base 181 and the second base 182 from each other.

Hereinafter, refer to FIG. 4 . Fig. 4 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. Hereinafter, differences between the plasma processing apparatus 1C shown in FIG. 4 and the plasma processing apparatus 1B will be described.

The plasma processing apparatus 1C does not have the second radio frequency power supply 62 . In addition, in the plasma processing apparatus 1C, the substrate support portion 16C may not have the dielectric body portion 22 , and the second support region 202 may be placed on the second base 182 via the bonding member 192 . In addition, the position in the height direction of the top surface of the second base 182 may be substantially the same as the position in the height direction of the top surface of the first base 181 .

The plasma processing apparatus 1C further includes an impedance circuit 91 and an impedance circuit 92 . The impedance circuit 91 is connected between the output of the first radio frequency power supply 61 (output of radio frequency power) and the first base 181 . The impedance circuit 91 may also have variable impedance. The impedance circuit 91 may also include a variable capacitor connected between the output of the first radio frequency power source 61 and the first base 181 . The impedance circuit 92 is connected between the output of the first radio frequency power supply 61 (output of radio frequency power) and the second base station 182 . The impedance circuit 92 may also have variable impedance. The impedance circuit 92 may also include a variable capacitor connected between the output of the first radio frequency power source 61 and the second base 182 . In the plasma processing apparatus 1C, the first radio frequency power source 61 is electrically connected to the first base 181 through the matching device 61m and the impedance circuit 91 . In addition, the first radio frequency power supply 61 is electrically connected to the second base station 182 through the matching device 62m and the impedance circuit 92 .

In the plasma processing device 1C, the electrostatic capacity per unit area between the output of the first radio frequency power source 61 (the output of the radio frequency power) and the edge ring ER can also be the output of the first radio frequency power source 61 (the output of the radio frequency power) and The capacitance per unit area between the substrates W is 0.8 times or more and 1.2 times or less. The capacitance between the output of the first RF power supply 61 and the edge ring ER is the capacitance of the electrical path of the RF power from the first RF power supply 61 to the edge ring ER, including the capacitance component of the impedance circuit 92 . The capacitance between the output of the first RF power supply 61 and the substrate W is the capacitance of the electrical path of the RF power from the first RF power supply 61 to the substrate W, including the capacitance component of the impedance circuit 91 .

In the plasma processing apparatus 1C, radio frequency power is supplied to the plasma from the first radio frequency power supply 61 through the impedance circuit 91 , the first base 181 , the first support region 201 , and the substrate W. In addition, radio frequency power is supplied to the plasma from the first radio frequency power source 61 through the impedance circuit 92, the second base 182, the second support region 202, and the edge ring ER. That is, the RF power supplied to the plasma on the substrate W and the RF power supplied to the plasma on the edge ring ER can be individually adjusted by the impedance circuit 91 and the impedance circuit 92 . Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate W and the radio frequency power per unit area supplied to the plasma on the edge ring ER can be reduced. Therefore, according to the plasma processing apparatus 1C, in-plane variation of the plasma processing on the substrate can be suppressed. In addition, the plasma processing apparatus 1C may have only one of the impedance circuit 91 and the impedance circuit 92 . At this time, the capacitance per unit area between the output of the first radio frequency power supply 61 and the edge ring ER may be 0.8 times or more than the capacitance per unit area between the output of the first radio frequency power supply 61 and the substrate W. 1.2 times or less.

Hereinafter, refer to FIG. 5 . Fig. 5 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. Hereinafter, differences between the plasma processing apparatus 1D shown in FIG. 5 and the plasma processing apparatus 1C will be described.

The plasma processing apparatus 1D does not have the bias power supply 72 . The plasma processing apparatus 1D further includes an impedance circuit 93 and an impedance circuit 94 . The impedance circuit 93 is connected between the output of the bias power supply 71 (output of bias energy) and the first base 181 . The impedance circuit 93 may also have variable impedance. The impedance circuit 93 may also include a variable capacitor connected between the output of the bias power supply 71 and the first base 181 . The impedance circuit 94 is connected between the output of the bias power supply 71 (output of bias energy) and the second base 182 . The impedance circuit 94 may also have variable impedance. The impedance circuit 94 may also include a variable capacitor connected between the output of the bias power supply 71 and the second base 182 .

In the plasma processing apparatus 1D, bias energy is supplied to the first base 181 from the bias power supply 71 through the impedance circuit 93 . Also, bias energy is supplied to the second base 182 from the bias power supply 71 via the impedance circuit 94 . That is, the bias energy from the bias power supply 71 is distributed to the first base 181 and the second base 182 at a distribution ratio adjusted by the impedance circuit 93 and the impedance circuit 94 .

In the plasma processing device 1D, the electrostatic capacity per unit area between the output of the first radio frequency power supply 61 (the output of radio frequency power) and the edge ring ER can also be the output of the first radio frequency power supply 61 (the output of radio frequency power) and The capacitance per unit area between the substrates W is 0.8 times or more and 1.2 times or less. The capacitance between the output of the first RF power supply 61 and the edge ring ER is the capacitance of the electrical path of the RF power from the first RF power supply 61 to the edge ring ER, including the capacitance component of the impedance circuit 92 . The capacitance between the output of the first RF power supply 61 and the substrate W is the capacitance of the electrical path of the RF power from the first RF power supply 61 to the substrate W, including the capacitance component of the impedance circuit 91 . In addition, the plasma processing apparatus 1D may have only one of the impedance circuit 91 and the impedance circuit 92 . At this time, the capacitance per unit area between the output of the first radio frequency power supply 61 and the edge ring ER may be 0.8 times or more than the capacitance per unit area between the output of the first radio frequency power supply 61 and the substrate W. 1.2 times or less.

Also, in the plasma processing device 1D, the electrostatic capacitance per unit area between the output of the bias power supply 71 (output of bias energy) and the edge ring ER can also be the output of the bias power supply 71 (output of bias energy) ) and the substrate W between 0.8 times and 1.2 times the capacitance per unit area. The capacitance between the output of the bias power supply 71 and the edge ring ER is the capacitance of the electrical path of the bias energy from the bias power supply 71 to the edge ring ER, including the capacitance component of the impedance circuit 94 . The capacitance between the output of the bias power supply 71 and the substrate W is the capacitance of the electrical path of the bias energy from the bias power supply 71 to the substrate W, including the capacitance component of the impedance circuit 93 . In addition, the plasma processing apparatus 1D may have only one of the impedance circuit 93 and the impedance circuit 94 . At this time, the capacitance per unit area between the output of the bias power supply 71 and the edge ring ER may be 0.8 times or more or 1.2 times the capacitance per unit area between the output of the bias power supply 71 and the substrate W. the following.

Hereinafter, refer to FIG. 6 . Fig. 6 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. The difference between the plasma processing apparatus 1E shown in FIG. 6 and the plasma processing apparatus 1 will be described below.

The plasma processing apparatus 1E has a substrate support unit 16E instead of the substrate support unit 16 . The substrate support unit 16E includes a base 18E, a first support region 20a, and a second support region 20b.

The base 18E is conductive. Submount 18E may also be formed of a conductive material such as aluminum. The base 18E includes a first portion 18a and a second portion 18b. The first part 18a has a substantially disc shape. The central axis of the first portion 18a approximately coincides with the axis AX. The second part 18b extends around the outer periphery of the first part 18a. The second part 18b may have a substantially ring shape when viewed from above. The central axis of the second portion 18b approximately coincides with the axis AX. The first part 18a and the second part 18b are integrated with each other.

In the plasma processing apparatus 1E, the first radio frequency power supply 61 is electrically connected to the base 18E through a matching device 61m. The bias power supply 71 is also electrically connected to the base 18E.

The first support region 20a is formed of a dielectric. The first support area 20a is provided above the first portion 18a. The first support region 20a supports the substrate W placed thereon. The first supporting region 20a may also be fixed to the top surface of the first part 18a by a bonding member 19 such as an adhesive. The first support region 20a may also include the main body 201m and the chuck electrode 201a similarly to the first support region 201 .

The second support region 20b is formed of a dielectric. The second support area 20b is provided above the second portion 18b. The second support area 20b supports the edge ring ER placed thereon. The second supporting region 20b may also be fixed to the top surface of the dielectric body portion 22 described later by the bonding member 19 . The second support region 20b may also include a main body 202m, a chuck electrode 202a, and a chuck electrode 202b similarly to the second support region 202 .

The position of the top surface of the second portion 18b may be lower than the position of the top surface of the first portion 18a. The thickness of the second support region 20b may be thinner than the thickness of the first support region 20a. The substrate supporting portion 16E further includes a dielectric portion 22 . The dielectric body portion 22 is provided between the second supporting region 20b and the second portion 18b and on the top surface of the second portion 18b. The dielectric body portion 22 is formed of a dielectric body similarly to the dielectric body portion 22 of the substrate support portion 16 .

In the plasma processing apparatus 1E, the adjustment power supply 80 applies a voltage to the edge ring ER to adjust the position of the upper end of the plasma sheath in the height direction above the edge ring ER. The adjustment power supply 80 can apply a voltage to the edge ring through an electrical path that does not include the submount 18E and the second support region 20b.

In the plasma processing apparatus 1E, the radio frequency power from the first radio frequency power source 61 is supplied to the plasma through the first part 18a, the first supporting region 20a, and the substrate W, and then passes through the second part 18b, the second supporting region 20b and the edge Ring ER, supply to plasma. In the plasma processing apparatus 1E, the difference between the capacitance between the first portion 18a and the substrate W and the capacitance between the second portion 18b and the edge ring ER can be reduced by the dielectric body. Therefore, the difference between the radio frequency power per unit area supplied to the plasma on the substrate W and the radio frequency power per unit area supplied to the plasma on the edge ring ER can be reduced. Therefore, according to the plasma processing apparatus 1E, in-plane variation of the plasma processing on the substrate W can be suppressed.

In the plasma processing apparatus 1E, the capacitance per unit area between the second part 18b and the edge ring ER may be 0.8 times or more or 1.2 times the capacitance per unit area between the first part 18a and the substrate W. the following.

In addition, in FIG. 6 , the first supporting region 20a and the second supporting region 20b are integrated with each other to form a single electrostatic chuck, and the first supporting region 20a and the second supporting region 20b may also be separated from each other.

In the following, the experiments conducted to evaluate the plasma processing equipment will be described. In the experiment, a plurality of plasma processing apparatuses having different capacitance ratios were used as the plasma processing apparatus having the same structure as the plasma processing apparatus 1E, and a sample substrate was etched to form a plurality of holes distributed in the plane. The capacitance ratio is a value obtained by dividing the capacitance per unit area between the base 18E and the edge ring ER by the capacitance per unit area between the base 18E and the sample substrate.

In the experiment, the roundness of the hole formed on the edge of the sample substrate was determined. The roundness is the value of the short diameter of the hole divided by the long diameter of the hole. The results of the experiment are shown in FIG. 7 . In FIG. 7, the horizontal axis shows the capacitance ratio of the plural plasma processing devices used in the experiment. In Fig. 7, the vertical axis shows the roundness. As shown in FIG. 7 , it was confirmed that when the capacitance ratio is 0.8 or more and 1.2 or less, holes with high roundness can be formed at the edge of the sample substrate. Therefore, it was confirmed that the electrostatic capacitance per unit area between the base (the second base 182 or the second part 18b) and the edge ring ER was equal to the difference between the base (the first base 181 or the first part 18a) and the substrate W. It is ideal to be 0.8 times or more and 1.2 times or less of the electrostatic capacity per unit area between them.

As above, various exemplary embodiments have been described, and various additions, omissions, substitutions, and changes are possible without being limited to the above-described exemplary embodiments. In addition, the requirements of different embodiments can be combined to form other embodiments.

From the above description, it should be understood that various embodiments of the present invention are described in this specification for the purpose of illustration, and that various changes can be made without departing from the scope and spirit of the present invention. Therefore, the various embodiments disclosed in this specification are not intended to be limited, and the true scope and spirit can be shown in the appended claims.

1: Plasma treatment device 1B: Plasma treatment device 1C: Plasma treatment device 1D: Plasma treatment device 1E: Plasma treatment device 10: chamber 10s: Internal space 12: Chamber body 12p: access 16: Substrate support part 16B: Substrate support part 16C: Substrate support part 16E: Substrate support part 17: Support Department 18E: Abutment 18a: Part 1 18b: Part 2 20a: 1st support area 20b: Second support area 22: Dielectric body 24:Dielectric body area 24B: Dielectric body region 28: Peripheral part 29: peripheral part 30: Upper electrode 34: top plate 36: Support body 36a: Gas diffusion chamber 36b: gas 36c: gas inlet 38: Gas supply pipe 40: Gas source group 41: valve group 42:Flow controller group 43: valve group 48: Baffle 50: exhaust device 51p: DC power supply 51s: switch 52: exhaust pipe 61: The first RF power supply 61m: Matcher 62: The second RF power supply 62m: matcher 71: Bias power supply 71m: Matcher 72: Bias power supply 72m: matcher 80:Adjust the power supply 91: Impedance circuit 92: Impedance circuit 93: Impedance circuit 94: Impedance circuit 181: The first abutment 182: The second abutment 191: Joining components 192: Joining components 201: 1st support area 201a: Sucker electrode 201m: Body 202: Second support area 202a: suction cup electrode 202b: suction cup electrode 202m: Body 521p: DC power supply 521s: switch 522p: DC power supply 522s: switch AX: axis ER: Edge Ring MC: Control Department W: Substrate

FIG. 1 is a diagram schematically showing a plasma processing apparatus according to an exemplary embodiment. Fig. 2 is a diagram showing the structure in a chamber of a plasma processing apparatus according to an exemplary embodiment. Fig. 3 is a diagram schematically showing a plasma processing apparatus according to another exemplary embodiment. Fig. 4 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. Fig. 5 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. Fig. 6 is a diagram schematically showing a plasma processing apparatus according to yet another exemplary embodiment. Fig. 7 is a graph showing the experimental results.

1: Plasma treatment device

10: chamber

10s: Internal space

16: Substrate support part

22: Dielectric body

24:Dielectric body area

51p: DC power supply

51s: switch

61: The first RF power supply

61m: Matcher

62: The second RF power supply

62m: matcher

71: Bias power supply

71m: Matcher

80:Adjust the power supply

181: The first abutment

182: The second abutment

191: Joining components

192: Joining components

201: 1st support area

201a: Sucker electrode

201m: Body

202: Second support area

202a: suction cup electrode

202b: suction cup electrode

202m: Body

521p: DC power supply

521s: switch

522p: DC power supply

522s: switch

ER: Edge Ring

W: Substrate

Claims (18)

A plasma treatment device, comprising: Chamber; The substrate supporting part is arranged in the chamber and includes: a first base with conductivity; a second base with conductivity, which is separated from the first base and surrounds the outer periphery of the first base and extend; the first support area is formed by a dielectric body, and is disposed above the first base and supports the substrate placed thereon; and the second support area is formed by a dielectric body, and is disposed on the first base The edge ring on the top of the second abutment and supported on it; a first radio frequency power supply for supplying radio frequency power for plasma generation to the first base station; and The second radio frequency power supply supplies radio frequency power for plasma generation to the second base station. The plasma processing device according to claim 1, wherein, The position of the top surface of the second abutment is lower than the position of the top surface of the first abutment, The thickness of the second support region is thinner than the thickness of the first support region, The substrate supporting portion further includes a dielectric portion disposed between the second supporting region and the second base and on the top surface of the second base. The plasma treatment device as claimed in claim 2, wherein, The dielectric part is a thermally sprayed ceramic film formed on the top surface of the second base. The plasma treatment device according to claim 2 or 3, wherein, The second support region is fixed to the second base by the bonding member provided between the dielectric body portion and the second support region and the dielectric body portion. The plasma treatment device according to any one of Claims 1 to 4 further has: a bias power supply for supplying bias energy for introducing ions from plasma to the substrate to the first base; Adjust the power supply and apply voltage to the edge ring to adjust the position of the upper end of the plasma sheath in the height direction above the edge ring. Such as the plasma treatment device of claim 5, wherein, Between the first base and the second base, a dielectric region is provided for supplying part of the bias energy from the first base to the second base. The plasma treatment device according to any one of Claims 1 to 4 further has: a first bias power supply for supplying bias energy for introducing ions from the plasma to the substrate to the first base; A second bias power supply supplies bias energy for introducing ions from the plasma to the edge ring to the second submount. The plasma treatment device according to any one of claims 1 to 7, wherein, The capacitance per unit area between the second base and the edge ring is not less than 0.8 times and not more than 1.2 times the capacitance per unit area between the first base and the substrate. A plasma treatment device, comprising: Chamber; The substrate supporting part is arranged in the chamber and includes: a first base, which is conductive; a second base, which is conductive, and is separated from the first base and surrounds the first base The outer periphery extends; the first support area is formed by a dielectric body, and is arranged above the first base, and supports the substrate placed thereon; and the second support area is formed by a dielectric body, and is set above the second abutment and supporting the edge ring placed thereon; A radio frequency power source that generates radio frequency power for plasma generation; and An impedance circuit is connected between the radio frequency power source and the first base station or the second base station. As the plasma treatment device of claim 9, it further has: a first bias power supply, which supplies bias energy for introducing ions from the plasma to the substrate to the first base; A second bias power supply supplies bias energy for introducing ions from the plasma to the edge ring to the second submount. As the plasma treatment device of claim 9, it further has: a bias power supply that generates bias energy for introducing ions from the plasma to the substrate and the edge ring; Another impedance circuit is connected between the bias power supply and the first base or the second base. The plasma treatment device according to any one of claims 9 to 11, wherein, The electrostatic capacitance per unit area between the radio frequency power supply and the edge ring is more than 0.8 times and less than 1.2 times the electrostatic capacitance per unit area between the radio frequency power supply and the substrate. A plasma treatment device, comprising: Chamber; The substrate supporting part is arranged in the chamber and includes: a base, which is conductive, and has a first part and a second part extending circumferentially outside the first part; the first supporting area is composed of a dielectric body formed, and arranged above the first part, and supports the substrate placed thereon; the edge ring on it; a radio frequency power supply, which supplies radio frequency power for plasma generation to the abutment; and Adjusting the power supply, which applies voltage to the edge ring to adjust the height direction position of the upper end of the plasma sheath above the edge ring; the position of the top surface of the second part is lower than the position of the top surface of the first part, The thickness of the second support region is thinner than the thickness of the first support region, The substrate support portion further includes a dielectric portion disposed between the second support region and the second portion on the top surface of the second portion. The plasma treatment device according to claim 13, wherein, The dielectric part is a thermally sprayed ceramic film formed on the top surface of the second part. The plasma treatment device according to claim 13 or 14, wherein, The second support region is fixed to the second portion by the bonding member provided between the dielectric body portion and the second support region and the dielectric body portion. The plasma treatment device according to any one of Claims 13 to 15, which further has: A bias power supply supplies bias energy to the submount for introducing ions from the plasma to the substrate and the edge ring. The plasma treatment device according to any one of claims 13 to 16, wherein, The capacitance per unit area between the second portion and the edge ring is not less than 0.8 times and not more than 1.2 times the capacitance per unit area between the first portion and the substrate. The plasma treatment device according to any one of claims 1 to 17, wherein, The first support area and the second support area are separate electrostatic chucks, or are integrated with each other to form a single electrostatic chuck.

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