WO2022259793A1 - 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 processing equipment

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

A plasma processing apparatus is used for plasma processing of substrates. A capacitively coupled plasma processing apparatus is known as one type of plasma processing apparatus. A capacitively coupled plasma processing apparatus includes a chamber, a substrate support, and a high frequency power supply. A substrate support is provided within the chamber and supports the substrate and the edge ring. A radio frequency power supply provides radio frequency power to generate a plasma from the gas within the chamber. High-frequency power is supplied, for example, to the base of the substrate support. Patent Document 1 below discloses such a plasma processing apparatus.

JP 2020-96176 A

The present disclosure provides a technique for suppressing in-plane variations in plasma processing on a substrate.

In one exemplary embodiment, a plasma processing apparatus is provided. A plasma processing apparatus includes a chamber, a substrate support, a first RF power supply, and a second RF power supply. A substrate support is provided within the chamber. The substrate support includes a first base, a second base, a first support area, and a second support area. The first base and the second base have conductivity. The second base is separated from the first base and extends to surround the outer periphery of the first base. A first support region is formed from a dielectric material, is disposed above the first base, and is configured to support a substrate placed thereon. A second support region is formed from a dielectric material and is disposed above the second base and configured to support an edge ring resting thereon. The first high-frequency power supply is configured to supply high-frequency power for plasma generation to the first base. The second high frequency power supply is configured to supply high frequency power for plasma generation to the second base.

According to one exemplary embodiment, it is possible to suppress in-plane variations in the plasma processing of the substrate.

1 schematically illustrates a plasma processing apparatus according to one exemplary embodiment; FIG. It is a figure which shows the structure in the chamber of the plasma processing apparatus which concerns on one exemplary embodiment. FIG. 2 schematically illustrates a plasma processing apparatus according to another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; FIG. 4 schematically illustrates a plasma processing apparatus according to yet another exemplary embodiment; It is a figure which shows the result of experiment.

Various exemplary embodiments are described below.

In one exemplary embodiment, a plasma processing apparatus is provided. A plasma processing apparatus includes a chamber, a substrate support, a first RF power supply, and a second RF power supply. A substrate support is provided within the chamber. The substrate support includes a first base, a second base, a first support area, and a second support area. The first base and the second base have conductivity. The second base is separated from the first base and extends to surround the outer periphery of the first base. A first support region is formed from a dielectric material, is disposed above the first base, and is configured to support a substrate placed thereon. A second support region is formed from a dielectric material and is disposed above the second base and configured to support an edge ring resting thereon. The first high-frequency power supply is configured to supply high-frequency power for plasma generation to the first base. The second high frequency power supply is configured to supply high frequency power for plasma generation to the second base.

In the above embodiment, high-frequency power from the first high-frequency power supply is supplied to the plasma through the first base, the first support region, and the substrate. Also, high frequency power from the second high frequency power supply is supplied to the plasma via the second base, the second support region, 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 adjusted independently. Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate and the RF power per unit area supplied to the plasma on the edge ring. Therefore, according to the above embodiment, it is possible to suppress in-plane variations in the plasma processing of the substrate.

In one 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 less than the thickness of the first support region. The substrate support may further include a dielectric portion provided between the second support region and the second base and on the upper surface of the second base. In this embodiment, the difference in capacitance between the first pedestal and substrate and the second pedestal and edge ring is reduced by the dielectric portion.

In one exemplary embodiment, the dielectric portion may be a thermally sprayed ceramic film formed on the upper surface of the second base.

In one exemplary embodiment, the second support area may be fixed to the second base through the joining member and the dielectric portion. A bonding member is provided between the dielectric portion and the second support region to secure the second support region to the dielectric portion.

In one exemplary embodiment, the plasma processing apparatus may further include a bias power supply and a regulated power supply. A bias power supply is configured to supply bias energy to the first pedestal for drawing ions from the plasma to the substrate. The adjustment power supply is configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring.

In one exemplary embodiment, between the first base and the second base is provided for delivering a portion of the bias energy from the first base to the second base. A dielectric region may be provided.

In one exemplary embodiment, the plasma processing apparatus may further include a first bias power supply and a second bias power supply. A first bias power supply is configured to supply bias energy to the first pedestal for drawing ions from the plasma to the substrate. A second bias power supply is configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring.

In one exemplary embodiment, the capacitance per unit area between the second pedestal and the edge ring is 0.00% of the capacitance per unit area between the first pedestal and the substrate. It may be 8 times or more and 1.2 times or less.

A plasma processing apparatus is also provided in another exemplary embodiment. A plasma processing apparatus includes a chamber, a substrate support, a high frequency power supply, and an impedance circuit. A substrate support is provided within the chamber. The substrate support includes a first base, a second base, a first support area, and a second support area. The first base and the second base have conductivity. The second base is separated from the first base and extends to surround the outer periphery of the first base. A first support region is formed from a dielectric material, is disposed above the first base, and is configured to support a substrate placed thereon. A second support region is formed from a dielectric material and is disposed above the second base and configured to support an edge ring resting thereon. A radio frequency power source is electrically coupled to the first base and the second base and is configured to generate radio frequency power for plasma generation. An impedance circuit is connected between the high frequency power source and the first base or the second base.

In the above embodiment, the high frequency power supplied to the plasma on the substrate and the high frequency power supplied to the plasma on the edge ring can be adjusted by the impedance circuit. Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate and the RF power per unit area supplied to the plasma on the edge ring. Therefore, according to the above embodiment, it is possible to suppress in-plane variations in the plasma processing of the substrate.

In one exemplary embodiment, the plasma processing apparatus may further include a first bias power supply and a second bias power supply. A first bias power supply is configured to supply bias energy to the first pedestal for drawing ions from the plasma to the substrate. A second bias power supply is configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring.

In one exemplary embodiment, the plasma processing apparatus may further comprise a bias power supply and another impedance circuit. A bias power supply is configured to generate bias energy for drawing ions from the plasma to the substrate and edge ring. An impedance circuit is connected between the bias power supply and the first base or the second base.

In one exemplary embodiment, the capacitance per unit area between the RF power supply and the edge ring is at least 0.8 times the capacitance per unit area between the RF power supply and the substrate,1. It may be twice or less.

A plasma processing apparatus is also provided in yet another exemplary embodiment. A plasma processing apparatus includes a chamber, a substrate support, a radio frequency power supply, and a regulated power supply. A substrate support is provided within the chamber. The substrate support includes a base, a first support area, and a second support area. The base has a first portion and a second portion extending circumferentially outside the first portion. A first support region is formed from a dielectric material, overlies the first portion, and is configured to support a substrate resting thereon. A second support region is formed from a dielectric material and overlies the second portion and is configured to support an edge ring resting thereon. The high frequency power supply is configured to supply high frequency power for plasma generation to the base. The adjustment power supply is configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring. The position of the top surface of the second portion is lower than the position of the top surface of the first portion. The thickness of the second support region is less than the thickness of the first support region. The substrate support further includes a dielectric portion disposed between the second support region and the second portion and on top of the second portion.

A regulated power supply may apply voltage to the edge ring via an electrical path that does not include the base and the second support area.

In the above embodiment, RF power from the RF power source is supplied to the plasma through the first portion, the first support region, and the substrate, and through the second portion, the second support region, and the edge ring. supplied to the plasma. In this embodiment, the difference in capacitance between the first portion and the substrate and between the second portion and the edge ring is reduced by the dielectric portion. Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate and the RF power per unit area supplied to the plasma on the edge ring. Therefore, according to the above embodiment, it is possible to suppress in-plane variations in the plasma processing of the substrate.

In one exemplary embodiment, the dielectric portion may be a thermally sprayed ceramic film formed on the upper surface of the second portion.

In one exemplary embodiment, the second support region may be fixed to the second portion via the joining member and the dielectric portion. A joining member is provided between the dielectric portion and the second support region, and fixes the second support region to the dielectric portion.

In one exemplary embodiment, the plasma processing apparatus may further include a bias power supply. A bias power supply is configured to provide bias energy to the pedestal for drawing ions from the plasma to the substrate and edge ring.

In one exemplary embodiment, the capacitance per unit area between the second portion and the edge ring is 0.8 times the capacitance per unit area between the first portion and the substrate. It may be greater than or equal to 1.2 times or less.

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

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

FIG. 1 is a diagram schematically showing a plasma processing apparatus according to one exemplary embodiment. A plasma processing apparatus 1 shown in FIG. 1 includes a chamber 10 . FIG. 2 is a diagram showing the configuration inside the chamber of the plasma processing apparatus according to one exemplary embodiment. As shown in FIG. 2, the plasma processing apparatus 1 may be a capacitively coupled plasma processing apparatus.

The chamber 10 provides an internal space 10s therein. The center axis of the internal space 10s is the axis AX extending in the vertical direction. In one embodiment, chamber 10 includes a chamber body 12 . The chamber body 12 has a substantially cylindrical shape. An interior space 10 s is provided within the chamber body 12 . The chamber body 12 is made of aluminum, for example. The chamber body 12 is electrically grounded. A plasma-resistant film is formed on the inner wall surface of the chamber main body 12, that is, on the wall surface defining the internal space 10s. The membrane can be a ceramic membrane, such as a membrane formed by an anodizing process or a membrane formed from yttrium oxide.

A passage 12p is formed in the side wall of the chamber main body 12. The substrate W passes through the passage 12p when being transported between the interior space 10s and the outside of the chamber 10. As shown in FIG. A gate valve 12g is provided along the side wall of the chamber body 12 for opening and closing the passage 12p.

The plasma processing apparatus 1 further includes a substrate support section 16 . The substrate support 16 is configured to support a substrate W placed thereon within the chamber 10 . The substrate W has a substantially disk shape. The substrate support portion 16 may be supported by the support portion 17 . The support portion 17 extends upward from the bottom portion of the chamber body 12 . The support portion 17 has a substantially cylindrical shape. The support portion 17 is made of an insulating material such as quartz.

The substrate support portion 16 is configured to further support the edge ring ER placed thereon. The edge ring ER is a plate having a substantially ring shape. The edge ring ER may have conductivity. The edge ring ER is made of silicon or silicon carbide, for example. A substrate W is placed in the chamber 10 on the substrate support 16 and within the area surrounded by the edge ring ER. The substrate W and edge ring ER are mounted on the substrate support 16 such that their central axes coincide with the axis AX.

The plasma processing apparatus 1 may further include 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 made of a conductive material and has a substantially cylindrical shape. The outer peripheral portion 28 is electrically grounded. A plasma-resistant film is formed on the surface of the outer peripheral portion 28 . The membrane can be a ceramic membrane, such as a membrane formed by an anodizing process or a membrane formed from yttrium oxide.

The outer peripheral portion 29 is provided on the outer peripheral portion 28 . The outer peripheral portion 29 is made of an insulating material. The outer peripheral portion 29 is made of ceramic 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 apparatus 1 further includes an upper electrode 30. The upper electrode 30 is provided above the substrate support portion 16 . The upper electrode 30 closes the upper opening of the chamber body 12 together with the member 32 . The member 32 has insulation. The upper electrode 30 is supported above the chamber body 12 via this member 32 .

The upper electrode 30 may include a top plate 34 and a support 36. A 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 plate thickness direction (vertical direction). The plurality of gas holes 34a are open toward the internal space 10s. The top plate 34 is made of silicon, for example. Alternatively, the top plate 34 may have a structure in which a plasma-resistant film is provided on the surface of an aluminum member. The membrane can be a ceramic membrane, such as a membrane formed by an anodizing process or a membrane formed from yttrium oxide.

The support 36 detachably supports the top plate 34 . The support 36 is made of a conductive material such as aluminum. The support 36 provides a gas diffusion chamber 36a therein. Support 36 further provides a plurality of gas holes 36b. A plurality of gas holes 36b extend downward from the gas diffusion chamber 36a. The multiple gas holes 36b communicate with the multiple gas holes 34a, respectively. Support 36 further provides gas inlet 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.

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, the valve group 41, the flow controller group 42, and the valve group 43 constitute a gas supply section. Gas source group 40 includes a plurality of gas sources. Each of the valve group 41 and the valve group 43 includes a plurality of valves (eg open/close valves). The flow controller group 42 includes a plurality of flow controllers. Each of the plurality of flow controllers in the flow controller group 42 is a mass flow controller or a pressure-controlled flow controller. Each of the plurality of gas sources of the gas source group 40 is connected to the gas supply pipe 38 via a corresponding valve of the valve group 41, a corresponding flow controller of the flow controller group 42, and a corresponding valve of the valve group 43. It is connected. The plasma processing apparatus 1 is capable of supplying gas from one or more gas sources selected from a plurality of gas sources in the gas source group 40 to the internal space 10s at individually adjusted flow rates. .

A baffle plate 48 is provided between the outer peripheral portion 28 and the side wall of the chamber body 12 . The baffle plate 48 can be configured by coating an aluminum member with ceramic such as yttrium oxide, for example. A large number of through holes are formed in the baffle plate 48 . An exhaust pipe 52 is connected to the bottom of the chamber body 12 below the baffle plate 48 . An exhaust device 50 is connected to the exhaust pipe 52 . The evacuation 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 controller MC. The controller MC is a computer including a processor, storage device, input device, display device, etc., and controls each part of the plasma processing apparatus 1 . Specifically, the controller MC executes a control program stored in the storage device, and controls each part of the plasma processing apparatus 1 based on the recipe data stored in the storage device. A process specified by the recipe data is executed in the plasma processing apparatus 1 under the control of the controller MC.

The substrate support portion 16 will be described in detail below. As shown in FIG. 1, the substrate support 16 includes a first base 181, a second base 182, a first support area 201, and a second support area 202. As shown in FIG.

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

The first support region 201 is made of a dielectric. The first support area 201 is provided above the first base 181 . The first support area 201 is configured to support a substrate W placed thereon. The first support area 201 may be fixed to the top surface of the first base 181 via a bonding member 191 such as an adhesive.

The first support region 201 may include a body 201m and a chuck electrode 201a. Body 201m is made of a dielectric such as aluminum oxide or aluminum nitride. The main body 201m has a substantially disk shape. The central axis of the main body 201m substantially coincides with the axis AX.

The chuck electrode 201a is provided inside the main body 201m. The chuck electrode 201a can be a membrane made of a conductive material. The chuck electrode 201a can have a substantially circular planar shape. The center of the chuck electrode 201a is positioned on the axis AX. The chuck electrode 201a is connected to a DC power supply 51p via a switch 51s. When the DC voltage from the DC power supply 51p is applied to the chuck electrode 201a, electrostatic attraction is generated between the first support region 201 and the substrate W. As shown in FIG. Due to the generated electrostatic attraction, the substrate W is attracted to the first support area 201 and held by the first support area 201 .

The second support region 202 is made of a dielectric. A second support area 202 is provided above the second base 182 . The second support area 202 is configured to support an edge ring ER resting thereon. The second support region 202 may be fixed to the top surface of the second base 182 or the top surface of the dielectric section 22 described below via a bonding member 192 such as an adhesive.

The second support region 202 may include a body 202m, a chuck electrode 202a, and a chuck electrode 202b. Body 202m is formed from a dielectric such as aluminum oxide or aluminum nitride. The body 202m extends circumferentially to surround the first support area 201 . Body 202m may have a generally annular shape. A central axis of the main body 202m substantially coincides with the axis AX.

The chuck electrodes 202a and 202b are provided in the main body 202m. Each of chuck electrodes 202a and 202b can be a membrane formed from a conductive material. The chuck electrodes 202a and 202b extend circumferentially around the axis AX. Chuck electrode 202b extends outside of chuck electrode 202a. Chuck electrodes 202a and 202b may have a generally annular shape. The center of each of chuck electrodes 202a and 202b is located on axis AX. The chuck electrode 202a is connected to a DC power supply 521p via a switch 521s. The chuck electrode 202b is connected to a DC power supply 522p via a switch 522s. When DC voltages from DC power sources 521p and 522p are applied to chuck electrodes 202a and 202b, respectively, electrostatic attraction is generated between second support region 202 and edge ring ER. Due to the generated electrostatic attraction, the edge ring ER is attracted to the second support area 202 and held by the second support area 202 .

The plasma processing apparatus 1 further includes a first high frequency power supply 61 and a second high frequency power supply 62 . The first high-frequency power supply 61 is configured to supply high-frequency power for plasma generation to the first base 181 . The first high frequency power supply 61 is electrically connected to the first base 181 via a matching box 61m. The high-frequency power generated by the first high-frequency power supply 61 has a frequency within the range of 27-100 MHz, eg, 40 MHz or 60 MHz. The matching unit 61m has a matching circuit for matching the load impedance of the first high frequency power supply 61 with the output impedance of the first high frequency power supply 61 .

The second high-frequency power supply 62 is configured to supply high-frequency power for plasma generation to the second base 182 . The second high frequency power supply 62 is electrically connected to the second base 182 via a matching box 62m. The high frequency power generated by the second high frequency power supply 62 can have the same frequency as the frequency of the high frequency power generated by the first high frequency power supply 61 . The matching device 62m has a matching circuit for matching the impedance of the load of the second high frequency power supply 62 with the output impedance of the second high frequency power supply 62 .

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

The plasma processing apparatus 1 may further include a bias power supply 71. A bias power supply 71 is electrically connected to the first base 181 . A bias power supply 71 generates the bias energy used to attract ions to the substrate W. FIG. The bias energy has a bias frequency. The bias frequency can be a frequency within the range of 50 kHz to 13.56 MHz.

In one embodiment, the bias energy may be radio frequency bias power having a bias frequency. In this embodiment, the bias power supply 71 is electrically connected to the first base 181 via a matching device 71m. The matching unit 71m has a matching circuit for matching the impedance of the load of the bias power supply 71 with the output impedance of the bias power supply 71 .

In another embodiment, the bias energy may be a pulse of voltage. Pulses of voltage are generated and applied to the first base 181 periodically at intervals of time (ie, bias period) having a time length that is 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 square wave or a triangular wave.

In the plasma processing apparatus 1, high-frequency power from the first high-frequency power supply 61 is supplied to the plasma through the first base 181, the first support region 201, and the substrate W. Also, high frequency power from the second high frequency power supply 62 is supplied to the plasma via the second base 182, the second support region 202, and the edge ring ER. That is, in the plasma processing apparatus 1, the high frequency power supplied to the plasma on the substrate W and the high frequency power supplied to the plasma on the edge ring ER can be individually adjusted. Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate W and the RF power per unit area supplied to the plasma on the edge ring. Therefore, according to the plasma processing apparatus 1, it is possible to suppress in-plane variations in the plasma processing of the substrate W. FIG.

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 support region 202 may be thinner than the thickness of the first support region 201 . The substrate support portion 16 may further include a dielectric portion 22 . The dielectric portion 22 is provided between the second support region 202 and the second base 182 and on the upper surface of the second base 182 . Dielectric portion 22 is made of a dielectric such as aluminum oxide or aluminum nitride. The dielectric portion 22 may be a thermally sprayed ceramic film formed on the upper surface of the second base 182 . In this embodiment, the difference in capacitance between the first base 181 and the substrate W and the second base 182 and the edge ring ER is reduced by the dielectric portion 22. be.

In one embodiment, the plasma processing apparatus 1 may further include a regulated power supply 80. The adjustment power supply 80 is configured to apply a voltage to the edge ring ER to adjust the heightwise position of the upper end of the plasma sheath above the edge ring ER.

In one embodiment, a dielectric region 24 may be provided between the first base 181 and the second base 182 . Dielectric region 24 is formed of a dielectric. Dielectric region 24 is provided to deliver a portion of the bias energy from first base 181 to second base 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 pedestal 182 and the edge ring ER is less than the capacitance per unit area between the first pedestal 181 and the substrate W. It may be 0.8 times or more and 1.2 times or less. According to this embodiment, it is possible to further reduce the difference between the RF power per unit area supplied to the plasma on the substrate W and the RF power per unit area supplied to the plasma on the edge ring.

Note that in the example shown in FIG. 1, the first support area 201 and the second support area 202 are separate electrostatic chucks separated from each other. However, the first support region 201 and the second support region 202 may be integrated together and form a single electrostatic chuck.

See Figure 3 below. FIG. 3 is a schematic diagram of a plasma processing apparatus according to another exemplary embodiment. Differences of the plasma processing apparatus 1B shown in FIG. 3 from the plasma processing apparatus 1 will be described below.

The plasma processing apparatus 1B further includes a bias power supply 72. Bias power supply 72 (second bias power supply) generates bias energy similar to the bias energy generated by bias power supply 71 (first bias power supply). A bias power supply 72 is electrically connected to the second base 182 . When the bias energy generated by the bias power supply 72 is high frequency bias power, the bias power supply 72 is electrically connected to the second base 182 via the matching box 72m. The matching device 72m has a matching circuit for matching the impedance of the load of the bias power supply 72 with the output impedance of the bias power supply 72 .

A dielectric region 24B is provided between a first base 181 and a second base 182 in the substrate support portion 16B of the plasma processing apparatus 1B. Dielectric region 24B has a relatively low capacitance to electrically isolate first base 181 and second base 182 from each other in the respective frequency bands of high frequency power and bias energy.

See Figure 4 below. FIG. 4 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1C shown in FIG. 4 from the plasma processing apparatus 1B will be described below.

The plasma processing apparatus 1C does not include the second high frequency power supply 62. Further, in the plasma processing apparatus 1C, the substrate supporting portion 16C does not have to have the dielectric portion 22, and the second supporting region 202 is placed on the second base 182 via the bonding member 192. may be placed. The position of the upper surface of the second base 182 in the height direction may be substantially the same as the position of the upper surface of the first base 181 in the height direction.

The plasma processing apparatus 1C further includes impedance circuits 91 and 92 . The impedance circuit 91 is connected between the output of the first high frequency power supply 61 (output of high frequency power) and the first base 181 . Impedance circuit 91 may have a variable impedance. Impedance circuit 91 may include a variable capacitor connected between the output of first high frequency power supply 61 and first base 181 . The impedance circuit 92 is connected between the output of the first high frequency power supply 61 (output of high frequency power) and the second base 182 . Impedance circuit 92 may have a variable impedance. Impedance circuit 92 may include a variable capacitor connected between the output of first high frequency power supply 61 and second base 182 . In the plasma processing apparatus 1C, the first high frequency power supply 61 is electrically connected to the first base 181 via the matching box 61m and the impedance circuit 91. As shown in FIG. Also, the first high-frequency power supply 61 is electrically connected to the second base 182 via the matching device 62m and the impedance circuit 92 .

In the plasma processing apparatus 1C, the capacitance per unit area between the output of the first high-frequency power supply 61 (output of high-frequency power) and the edge ring ER is equal to the output of the first high-frequency power supply 61 (output of high-frequency power ) and the substrate W may be 0.8 times or more and 1.2 times or less of the capacitance per unit area. The capacitance between the output of the first high frequency power supply 61 and the edge ring ER is the capacitance of the electrical path of the high frequency power from the first high frequency power supply 61 to the edge ring ER. Contains a capacitive component. The capacitance between the output of the first high-frequency power source 61 and the substrate W is the capacitance of the electrical path of the high-frequency power from the first high-frequency power source 61 to the substrate W, and the capacitance of the impedance circuit 91 Contains ingredients.

In the plasma processing apparatus 1C, high-frequency power is supplied from the first high-frequency power supply 61 to the plasma through the impedance circuit 91, the first base 181, the first support region 201, and the substrate W. Also, high frequency power is supplied to the plasma from the first high frequency power source 61 via the impedance circuit 92, the second base 182, the second support region 202, and the edge ring ER. That is, the high frequency power supplied to the plasma on the substrate W and the high frequency power supplied to the plasma on the edge ring ER can be individually adjusted by the impedance circuits 91 and 92 . Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate W and the RF power per unit area supplied to the plasma on the edge ring ER. Therefore, according to the plasma processing apparatus 1C, it is possible to suppress in-plane variations in the plasma processing of the substrate. In addition, the plasma processing apparatus 1</b>C may include only one of the impedance circuit 91 and the impedance circuit 92 . Even in this case, the capacitance per unit area between the output of the first high-frequency power supply 61 and the edge ring ER is equal to the static capacitance per unit area between the output of the first high-frequency power supply 61 and the substrate W. It may be 0.8 times or more and 1.2 times or less of the electric capacity.

See Figure 5 below. FIG. 5 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1D shown in FIG. 5 from the plasma processing apparatus 1C will be described below.

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

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

In the plasma processing apparatus 1D, the capacitance per unit area between the output of the first high-frequency power supply 61 (output of high-frequency power) and the edge ring ER is equal to the output of the first high-frequency power supply 61 (output of high-frequency power ) and the substrate W may be 0.8 times or more and 1.2 times or less of the capacitance per unit area. The capacitance between the output of the first high frequency power supply 61 and the edge ring ER is the capacitance of the electrical path of the high frequency power from the first high frequency power supply 61 to the edge ring ER. Contains a capacitive component. The capacitance between the output of the first high-frequency power source 61 and the substrate W is the capacitance of the electrical path of the high-frequency power from the first high-frequency power source 61 to the substrate W, and the capacitance of the impedance circuit 91 Contains ingredients. The plasma processing apparatus 1D may include only one of the impedance circuit 91 and the impedance circuit 92. FIG. Even in this case, the capacitance per unit area between the output of the first high-frequency power supply 61 and the edge ring ER is equal to the static capacitance per unit area between the output of the first high-frequency power supply 61 and the substrate W. It may be 0.8 times or more and 1.2 times or less of the electric capacity.

In the plasma processing apparatus 1D, the capacitance per unit area between the output of the bias power supply 71 (output of bias energy) and the edge ring ER is the output of the bias power supply 71 (output of bias energy) and the substrate W It may be 0.8 times or more and 1.2 times or less of the capacitance per unit area between. The capacitance between the output of bias power supply 71 and edge ring ER is the capacitance of the electrical path of the bias energy from bias power supply 71 to edge ring ER and includes the capacitive component of impedance circuit 94 . The capacitance between the output of bias power supply 71 and substrate W is the capacitance of the electrical path of the bias energy from bias power supply 71 to substrate W and includes the capacitive component of impedance circuit 93 . Note that the plasma processing apparatus 1D may include only one of the impedance circuit 93 and the impedance circuit 94. FIG. Even in this case, the capacitance per unit area between the output of the bias power supply 71 and the edge ring ER is 0.8 of the capacitance per unit area between the output of the bias power supply 71 and the substrate W. It may be more than twice and less than 1.2 times.

See Figure 6 below. FIG. 6 is a schematic diagram of a plasma processing apparatus according to yet another exemplary embodiment. Differences of the plasma processing apparatus 1E shown in FIG. 6 from the plasma processing apparatus 1 will be described below.

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

The base 18E has conductivity. The base 18E may be made of a conductive material such as aluminum. The base 18E includes a first portion 18a and a second portion 18b. The first portion 18a has a substantially disk shape. The central axis of the first portion 18a substantially coincides with the axis AX. The second portion 18b extends to surround the outer circumference of the first portion 18a. The second portion 18b may have a substantially annular shape in plan view. The central axis of the second portion 18b substantially coincides with the axis AX. The first portion 18a and the second portion 18b are integrated with each other.

In the plasma processing apparatus 1E, the first high frequency power supply 61 is electrically connected to the base 18E via a matching box 61m. A bias power supply 71 is also electrically connected to the base 18E.

The first support region 20a is made of a dielectric. A first support area 20a is provided above the first portion 18a. The first support area 20a is configured to support a substrate W placed thereon. The first support area 20a may be secured to the top surface of the first portion 18a via a bonding member 19 such as an adhesive. First support region 20a, like first support region 201, may include body 20m and chuck electrode 201a.

The second support region 20b is made of a dielectric. A second support area 20b is provided above the second portion 18b. The second support area 20b is configured to support an edge ring ER resting thereon. The second support region 20b may be fixed to the upper surface of the dielectric portion 22, which will be described later, via the joint member 19. As shown in FIG. Second support region 20b, like second support region 202, may include body 20m, chuck electrode 202a, and chuck electrode 202b.

The position of the upper surface of the second portion 18b may be lower than the position of the upper 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 support portion 16E further includes a dielectric portion 22. As shown in FIG. The dielectric portion 22 is provided between the second support region 20b and the second portion 18b and on the upper surface of the second portion 18b. The dielectric portion 22 is made of a dielectric material, like the dielectric portion 22 of the substrate support portion 16 .

In the plasma processing apparatus 1E, the adjustment power supply 80 is configured to apply a voltage to the edge ring ER in order to adjust the height direction position of the upper end of the plasma sheath above the edge ring ER. Regulated power supply 80 may apply voltage to the edge ring via an electrical path that does not include base 18E and second support region 20b.

In the plasma processing apparatus 1E, high-frequency power from the first high-frequency power supply 61 is supplied to the plasma through the first portion 18a, the first support region 20a, and the substrate W, and the second portion 18b, the second is supplied to the plasma via the support region 20b of the and the edge ring ER. In the plasma processing apparatus 1E, the difference in capacitance between the first portion 18a and the substrate W and between the second portion 18b and the edge ring ER is reduced by the dielectric portion 22. . Therefore, it is possible to reduce the difference between the RF power per unit area supplied to the plasma on the substrate W and the RF power per unit area supplied to the plasma on the edge ring ER. Therefore, according to the plasma processing apparatus 1E, it is possible to suppress in-plane variations in the plasma processing of the substrate W. FIG.

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

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

The following describes the experiments conducted to evaluate the plasma processing equipment. In the experiment, a plurality of plasma processing apparatuses having the same structure as the plasma processing apparatus 1E and having different capacitance ratios were used to etch the sample substrate so as 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 holes formed on the edge of the sample substrate was determined. The circularity is a value obtained by dividing the short diameter of the hole by the long diameter of the hole. FIG. 7 shows the results of the experiment. In FIG. 7, the horizontal axis indicates capacitance ratios of a plurality of plasma processing apparatuses used in the experiment. In FIG. 7, the vertical axis indicates the circularity. As shown in FIG. 7, it was confirmed that holes with high roundness can be formed even at the edge of the sample substrate when the capacitance ratio is 0.8 or more and 1.2 or less. Therefore, the capacitance per unit area between the base (second base 182 or second portion 18b) and the edge ring ER is ) and the substrate W is preferably 0.8 times or more and 1.2 times or less of the capacitance per unit area.

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

Various exemplary embodiments included in the present disclosure are now described in [E1] to [E18] below.

[E1]
a chamber;
A substrate support provided in the chamber,
a conductive first base;
a second electrically conductive base spaced apart from the first base and extending around the circumference of the first base;
a first support region formed from a dielectric and disposed above the first base and configured to support a substrate mounted thereon;
a second support region formed from a dielectric and disposed above the second base and configured to support an edge ring resting thereon;
the substrate support comprising
a first high frequency power supply configured to supply high frequency power for plasma generation to the first base;
a second high frequency power supply configured to supply high frequency power for plasma generation to the second base;
A plasma processing apparatus comprising:

[E2]
the position of the upper surface of the second base is lower than the position of the upper surface of the first base;
the thickness of the second support region is thinner than the thickness of the first support region;
The substrate support further includes a dielectric part provided between the second support region and the second base and on the upper surface of the second base,
The plasma processing apparatus according to [E1].

[E3]
The plasma processing apparatus according to [E2], wherein the dielectric section is a thermally sprayed ceramic film formed on the upper surface of the second base.

[E4]
The second support region is fixed to the second base via a joint member provided between the dielectric portion and the second support region and the dielectric portion, [E2 ] or the plasma processing apparatus as described in [E3].

[E5]
a bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
an adjustment power supply configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring;
The plasma processing apparatus according to any one of [E1] to [E4], further comprising:

[E6]
a dielectric region between the first base and the second base for supplying a portion of the bias energy from the first base to the second base; is provided, the plasma processing apparatus according to [E5].

[E7]
a first bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
a second bias power supply configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring;
The plasma processing apparatus according to any one of [E1] to [E4], further comprising:

[E8]
the capacitance per unit area between the second base and the edge ring is 0.8 times or more the capacitance per unit area between the first base and the substrate; The plasma processing apparatus according to any one of [E1] to [E7], which is 1.2 times or less.

[E9]
a chamber;
A substrate support provided in the chamber,
a conductive first base;
a second electrically conductive base spaced apart from the first base and extending around the circumference of the first base;
a first support region formed from a dielectric and disposed above the first base and configured to support a substrate mounted thereon;
a second support region formed from a dielectric and disposed above the second base and configured to support an edge ring resting thereon;
the substrate support comprising
a radio frequency power source electrically coupled to the first base and the second base and configured to generate radio frequency power for plasma generation;
an impedance circuit connected between the high-frequency power source and the first base or the second base;
A plasma processing apparatus comprising:

[E10]
a first bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
a second bias power supply configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring;
The plasma processing apparatus according to [E9], further comprising:

[E11]
a bias power supply configured to generate bias energy for drawing ions from a plasma into the substrate and the edge ring;
another impedance circuit connected between the bias power supply and the first base or the second base;
The plasma processing apparatus according to [E9], further comprising:

[E12]
The capacitance per unit area between the high-frequency power supply and the edge ring is 0.8 times or more and 1.2 times or less the capacitance per unit area between the high-frequency power supply and the substrate. The plasma processing apparatus according to any one of [E9] to [E11].

[E13]
a chamber;
A substrate support provided in the chamber,
an electrically conductive base having a first portion and a second portion extending circumferentially outside the first portion;
a first support region formed from a dielectric and disposed above the first portion and configured to support a substrate resting thereon;
a second support region formed from a dielectric material overlying the second portion and configured to support an edge ring resting thereon;
the substrate support comprising
a high-frequency power source configured to supply high-frequency power for plasma generation to the base;
an adjustment power supply configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring;
with
the position of the top surface of the second portion is lower than the position of the top surface of the first portion;
the thickness of the second support region is thinner than the thickness of the first support region;
the substrate support further includes a dielectric portion provided between the second support region and the second portion and on the upper surface of the second portion;
Plasma processing equipment.

[E14]
The plasma processing apparatus according to [E13], wherein the dielectric section is a thermally sprayed ceramic film formed on the upper surface of the second portion.

[E15]
The second support region is fixed to the second portion via a bonding member provided between the dielectric portion and the second support region and the dielectric portion, [E13] Or the plasma processing apparatus according to [E14].

[E16]
The plasma of any one of [E13]-[E15], further comprising a bias power supply configured to supply bias energy to the base for drawing ions from the plasma into the substrate and the edge ring. processing equipment.

[E17]
1. the capacitance per unit area between the second portion and the edge ring is 0.8 times or more the capacitance per unit area between the first portion and the substrate; The plasma processing apparatus according to any one of [E13] to [E16], which is twice or less.

[E18]
The first support region and the second support region are separate electrostatic chucks separated from each other or integrated with each other to form a single electrostatic chuck, [E1]-[ E17].

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

Reference Signs List 1 plasma processing apparatus 10 chamber 181 first base 182 second base 201 first support region 202 second support region 61 first high-frequency power supply 62 . . . second high-frequency power supply;

Claims (18)

a chamber;
A substrate support provided in the chamber,
a conductive first base;
a second electrically conductive base spaced apart from the first base and extending around the circumference of the first base;
a first support region formed from a dielectric and disposed above the first base and configured to support a substrate mounted thereon;
a second support region formed from a dielectric and disposed above the second base and configured to support an edge ring resting thereon;
the substrate support comprising
a first high frequency power supply configured to supply high frequency power for plasma generation to the first base;
a second high frequency power supply configured to supply high frequency power for plasma generation to the second base;
A plasma processing apparatus comprising: the position of the upper surface of the second base is lower than the position of the upper surface of the first base;
the thickness of the second support region is thinner than the thickness of the first support region;
The substrate support further includes a dielectric part provided between the second support region and the second base and on the upper surface of the second base,
The plasma processing apparatus according to claim 1. 3. The plasma processing apparatus according to claim 2, wherein said dielectric portion is a ceramic sprayed film formed on said upper surface of said second base. 3. The second support region is fixed to the second base via a joint member provided between the dielectric portion and the second support region and the dielectric portion. 3. The plasma processing apparatus according to 2. a bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
an adjustment power supply configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring;
The plasma processing apparatus according to any one of claims 1 to 4, further comprising: a dielectric region between the first base and the second base for supplying a portion of the bias energy from the first base to the second base; 6. The plasma processing apparatus of claim 5, further comprising: a first bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
a second bias power supply configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring;
The plasma processing apparatus according to any one of claims 1 to 4, further comprising: the capacitance per unit area between the second base and the edge ring is 0.8 times or more the capacitance per unit area between the first base and the substrate; 5. The plasma processing apparatus according to any one of claims 1 to 4, which is 1.2 times or less. a chamber;
A substrate support provided in the chamber,
a conductive first base;
a second electrically conductive base spaced apart from the first base and extending around the circumference of the first base;
a first support region formed from a dielectric and disposed above the first base and configured to support a substrate mounted thereon;
a second support region formed from a dielectric and disposed above the second base and configured to support an edge ring resting thereon;
the substrate support comprising
a radio frequency power source electrically coupled to the first base and the second base and configured to generate radio frequency power for plasma generation;
an impedance circuit connected between the high-frequency power source and the first base or the second base;
A plasma processing apparatus comprising: a first bias power supply configured to supply bias energy to the first pedestal for drawing ions from a plasma to the substrate;
a second bias power supply configured to supply bias energy to the second pedestal for drawing ions from the plasma into the edge ring;
10. The plasma processing apparatus of claim 9, further comprising: a bias power supply configured to generate bias energy for drawing ions from a plasma into the substrate and the edge ring;
another impedance circuit connected between the bias power supply and the first base or the second base;
10. The plasma processing apparatus of claim 9, further comprising: The capacitance per unit area between the high-frequency power supply and the edge ring is 0.8 times or more and 1.2 times or less the capacitance per unit area between the high-frequency power supply and the substrate. A plasma processing apparatus according to any one of claims 9 to 11. a chamber;
A substrate support provided in the chamber,
an electrically conductive base having a first portion and a second portion extending circumferentially outside the first portion;
a first support region formed from a dielectric and disposed above the first portion and configured to support a substrate resting thereon;
a second support region formed from a dielectric material overlying the second portion and configured to support an edge ring resting thereon;
the substrate support comprising
a high-frequency power source configured to supply high-frequency power for plasma generation to the base;
an adjustment power supply configured to apply a voltage to the edge ring to adjust the heightwise position of the upper end of the plasma sheath above the edge ring;
with
the position of the top surface of the second portion is lower than the position of the top surface of the first portion;
the thickness of the second support region is thinner than the thickness of the first support region;
the substrate support further includes a dielectric portion provided between the second support region and the second portion and on the upper surface of the second portion;
Plasma processing equipment. 14. The plasma processing apparatus according to claim 13, wherein said dielectric portion is a ceramic sprayed film formed on said upper surface of said second portion. 13. The second support region is fixed to the second portion via a bonding member provided between the dielectric portion and the second support region and the dielectric portion. 3. The plasma processing apparatus according to . 16. The plasma processing apparatus of any one of claims 13 to 15, further comprising a bias power supply configured to supply bias energy to the base for drawing ions from the plasma into the substrate and the edge ring. . 1. the capacitance per unit area between the second portion and the edge ring is 0.8 times or more the capacitance per unit area between the first portion and the substrate; 16. The plasma processing apparatus according to any one of claims 13 to 15, which is two times or less. Claims 1-4, wherein the first support region and the second support region are separate electrostatic chucks separated from each other or integrated with each other to form a single electrostatic chuck. , 9-11, and 13-15.

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