JP2000173988A - Substrate holder and plasma treating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate holder making it possible to more reduce the sample contamination with metals (Al) due to sputtering on the surface of a focus ring and realize the uniformity of the sample treatment. SOLUTION: The substrate holder comprises an electrode 33 applied to a high frequency power for mounting a substrate to be a work, a focus ring 30 of an insulator surrounding and covering the substrate (W) mounted on the electrode, an edge ring 35 which is made of a material having a conductivity not less than that of the substrate and disposed outside the substrate on the electrode, and a cover 36 which is disposed outside the edge ring above the focus ring through a space. The cover 36 is constituted to prevent a plasma from being irradiated on the focus ring and made of a material not contaminating the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for generating plasma in a processing vessel using microwaves, and etching, ashing, or the like of an object to be processed such as a semiconductor substrate or a glass substrate for a liquid crystal display by the generated plasma. CV
The present invention relates to a substrate holder used in a plasma processing apparatus for performing a process such as D (Chemical Vapor Deposition), and to this plasma processing apparatus.

[0002]

2. Description of the Related Art In a conventional plasma processing apparatus, a substrate holding table 103 on which a sample S such as a substrate is placed has a microwave introduction window hermetically sealed by a microwave introduction plate 104 as shown in FIG. It is provided in the processing container 101. The microwave oscillated from the microwave oscillator 120 travels from the waveguide 121 through the derivative line 114, passes through the microwave introduction plate 104, and is introduced into the processing container 101.

A high frequency power is applied to the substrate holding table 103 by a high frequency power supply 107 so that a stable bias voltage is applied to the surface of the sample S when the sample S is processed. As a result, the energy of the ions in the plasma can be controlled, and the ions of the appropriate energy can be irradiated to the surface of the sample S.

[0004] The side surface of the substrate holder 103 is covered with a focus ring 130 for shielding plasma. The substrate holder 103 has a structure in which alumina (Al ₂ O ₃ ) is thermally sprayed on the surface of an electrode 133 made of aluminum. Alumina (Al ₂ O ₃ ) is used as a material of the focus ring 130.

[0005] As shown in FIG.
The microwave oscillated by 0 is incident on the end of the dielectric line 141 by the waveguide 121. The planar shape of the dielectric line 141 is a substantially pentagon in which one side of a rectangle is combined with the base of a substantially isosceles triangle having a length equal to the one side, and is equivalent to the vertex of the substantially isosceles triangle. The waveguide 121 is connected to the end to be introduced, and microwaves are introduced.

[0006] The two isosceles of the substantially isosceles triangle form a tapered portion 141A.
Following the tapered portion 141A, it is evenly spread in the width direction and propagates throughout the dielectric line 141, and
1, a standing wave is formed. Since the standing wave can be formed uniformly by the tapered portion 141A, the microwave introduced into the processing container 101 can be made uniform even when the diameter of the processing container 101 becomes large. In addition, a large-diameter sample S can be uniformly plasma-processed.

[0007]

According to the above-described plasma processing apparatus, the surface of the focus ring is sputtered by the plasma, which causes metal contamination (aluminum contamination) on the sample. Further, the electric field concentrates on the outer edge of the processed surface of the sample, which hinders uniform processing of the sample. In addition, the concentrated electric field wraps around the electrode and may destroy the electrode.

In addition, the tapered portion of the dielectric line provided to uniformly spread the microwave incident on the dielectric line from the waveguide to the dielectric line projects horizontally from the processing container. . Therefore, in order to install the apparatus as shown in FIG. 5, in addition to the space corresponding to the size of the processing container, an extra space is required for storing the protruding tapered portion.

Therefore, the present invention can further reduce metal contamination of a sample due to sputtering on the surface of a focus ring, can realize uniform processing of a sample, and hold a substrate without causing electrode destruction. It is an object to provide a table and a plasma processing apparatus provided with the substrate holding table. Another object of the present invention is to provide a plasma processing apparatus that can be installed in a smaller space.

[0010]

In order to achieve the above object, a substrate holding table 3 according to the first aspect of the present invention is provided with an electrode to which a high frequency power is applied and a substrate W is placed, as shown in FIG. 33; a focus ring 30 of an insulator disposed around the electrode 33 so as to surround the electrode 33; and disposed outside the substrate W placed on the electrode 33 and having the same degree or the substrate W as the substrate W. An edge ring 35 formed of the above-mentioned conductive material; a cover component 36 disposed outside the edge ring 35 and disposed above the focus ring 30 via a gap 37;
Is characterized in that the plasma is not irradiated to the focus ring 30 and is made of a material that does not cause contamination of the substrate W.

With this configuration, since high-frequency power is applied to the electrode on which the substrate is mounted, a bias potential is generated at the electrode. The bias potential is controlled by controlling the high-frequency power, and the energy of ions in the plasma is reduced. By independently controlling, the processability of the substrate can be improved. Alternatively, since the substrate holder is provided with a focus ring, it is possible to prevent a high-frequency electric field of high-frequency power applied to the electrode from leaking in a horizontal circumferential direction of the electrode, and the high-frequency power works effectively on the substrate, Can be improved in workability.

Since the substrate holder has an edge ring,
Concentration of the electric field by the high-frequency power is caused at the outer edge of the edge ring, not at the outer edge of the substrate.Electric field components are equal at the outer edge of the substrate and the inner portion of the substrate, and the plasma is uniformly irradiated on the substrate. Thus, the substrate can be uniformly processed. Further, since the substrate holding base is provided with the cover component, plasma generated directly above the focus ring is not irradiated to the focus ring, so that the focus ring can be prevented from being shaved by the plasma.

Since the cover component is disposed above the focus ring via a gap, heat is transmitted from the cover component to the focus ring, making it difficult to escape, and the cover component is easily heated by plasma irradiation. When the temperature of the cover component is higher, the reaction product is less likely to adhere to the cover component itself, so that particles generated when the reaction product attached to the cover component peels off again can be reduced.

According to a second aspect of the present invention, there is provided a substrate holding table,
2. The substrate holder according to claim 1, wherein the edge ring is made of silicon (Si) or silicon carbide (Si).
C) and said cover part is made of silicon (S
i), characterized by being formed of silicon carbide (SiC) or silicon oxide (SiO ₂ ).

Since the edge ring is formed of a semiconductor material such as silicon or silicon carbide having a conductivity equal to or higher than that of the substrate, the potentials of the substrate surface and the edge ring surface outside the substrate are made substantially equal, and the outer edge of the substrate is formed. The concentration of the electric field can be prevented, and the uniformity of the processing of the substrate can be achieved. Further, deposition of reaction products and particles on the same surface as the substrate can be reduced. Since the cover component is formed of silicon, silicon carbide or silicon oxide, deposition of reaction products and particles on the surface of the substrate can be reduced.

According to a third aspect of the present invention, there is provided a plasma processing apparatus comprising: a substrate holding table according to the first or second aspect;
A processing chamber provided with the substrate holding table and having a gas supply port for supplying a reaction gas; and a microwave introduction unit for introducing microwaves into the processing chamber.

A substrate is placed on a substrate holding table in a processing chamber, a reaction gas is supplied from a gas supply port, and microwaves oscillated from a microwave oscillator are introduced into the processing chamber by microwave introduction means. A plasma is generated and the substrate is processed by the plasma.

According to a fourth aspect of the present invention, in the plasma processing apparatus according to the third aspect, the microwave introducing means includes: a microwave for sealing the processing chamber and transmitting the microwave; An introduction plate; an annular tubular member attached to a surface of the microwave introduction plate opposite to the processing chamber, the introduction port for introducing the microwave being opened on a peripheral side surface, and an annular tubular member for transmitting the microwave; A slit plate provided between the tubular member and the microwave introduction plate, facing the tubular member and the microwave introduction plate, and provided with a predetermined slit through which the microwave passes. It is characterized by the following.

The annular tubular member is typically a donut-shaped channel-shaped member having a partly opened longitudinal section formed in an annular shape, and a slit plate closes the open portion. It is configured as follows. The slit plate may be formed integrally with the annular tubular member, or may be formed as a separate member. When integrally formed, a tubular member having a closed cross section is constituted by a tubular member and a slit plate having a part of the vertical cross section opened. An antenna is configured including the annular tubular member and the slit plate.

Microwaves entering the annular tubular member from the inlet become traveling waves traveling in opposite directions in the tubular member and propagate through the tubular member, and both traveling waves enter the inlet of the tubular member. At the opposing positions, they collide with each other to form a standing wave.

Due to the standing wave, a current that reaches a maximum at predetermined intervals flows through the wall surface of the tubular member. Under the tubular member, a slit is formed in a slit plate provided opposite to the sealing member and the tubular member, and a potential difference is generated between the inside and outside of the tubular member with the slit interposed therebetween due to the above-described current, and this potential difference is generated. As a result, an electric field is emitted from the slit to the sealing member. That is, the microwave propagates from the tubular member to the sealing member. The microwave passes through the sealing member and is introduced into the processing chamber, and plasma is generated by the microwave.

Since the microwave can be directly incident on the inside of the tubular member in this manner, the tubular member does not protrude from the processing vessel defining the processing chamber, and thus the horizontal dimension of the plasma processing apparatus is reduced. Can be smaller. On the other hand, since the microwave is guided from the tubular member to substantially the entire region of the processing chamber and is radiated from the slit, the microwave can be uniformly introduced into the processing chamber.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic front sectional view showing the structure of the plasma processing apparatus according to the first embodiment of the present invention. FIG. 2 is a schematic plan view of the plasma processing apparatus shown in FIG. As shown in FIGS. 1 and 2, the plasma processing apparatus of the present embodiment includes a processing vessel 1 having a bottomed cylindrical shape entirely made of aluminum. The processing chamber 1 defines a processing chamber 2 in which the processing of the substrate W is performed. A microwave introduction window is opened in a vertically upper part of the processing container 1, and the microwave introduction window is hermetically sealed by a microwave introduction plate 4. The microwave introduction plate 4 is formed of a dielectric material such as quartz glass or alumina having heat resistance and microwave permeability and low dielectric loss. The processing container 1 is electrically grounded.

A part of the upper surface and the outer peripheral side surface of the above-described microwave introduction plate 4 are covered with a cover member 10 formed by shaping a conductive metal into an annular lid. It is fixed on the top. The cover member 10 has a shape in which the center of the portion corresponding to the upper surface of the microwave introduction plate is hollowed out in a circular shape. An antenna 11 for introducing microwaves into the processing chamber 1 is provided on an upper surface of the cover member 10. The antenna 11 is connected to the cover member 10.
And an annular waveguide-type antenna unit 12 as a tubular member formed in an annular shape. A plurality of slits 15, 15,... Are formed in a portion of the cover member 10 facing the annular waveguide antenna section 12.
Therefore, the cover member 10 also serves as a slit plate.

The annular waveguide antenna section 12 is provided slightly inside the inner peripheral surface of the processing container 1 and concentric with the central axis of the processing container 1. Further, an introduction portion 13 for introducing microwaves into the annular waveguide type antenna portion 12 is arranged at an introduction port 13A provided on the outer peripheral surface thereof in a diametric direction of the annular waveguide type antenna portion 12 so as to be annular. It is connected to the waveguide antenna unit 12. The antenna 11 is configured to include the annular waveguide antenna unit 12, the introduction unit 13, and the slit 15. Introducing section 13 and annular waveguide antenna section 12
Inside, a dielectric 14 such as a fluororesin such as Teflon (registered trademark), a polyethylene resin, or a polystyrene resin (preferably Teflon) is charged almost entirely in the internal space. A horizontally arranged waveguide 21 is connected to the introduction section 13, and a microwave oscillator 20 is connected to the waveguide 21.

The microwave oscillated by the microwave oscillator 20 enters the introduction section 13 of the antenna 11 via the waveguide 21. This incident wave is introduced from the introduction unit 13 to the annular waveguide antenna unit 12. The microwave introduced into the annular waveguide type antenna unit 12 travels in the annular waveguide type antenna unit 12 in the opposite directions to each other and travels through the dielectric 14 in the annular waveguide type antenna unit 12. Propagate. Both traveling waves are introduced into the inlet 13A of the annular waveguide antenna unit 12.
And a standing wave is generated.

Due to the standing wave, a current having a maximum value flows through the inner surface of the annular waveguide type antenna section 12 at predetermined intervals. The electric current causes a potential difference between the inside and outside of the annular waveguide antenna section 12 across the slits 15, 15,..., And an electric field is radiated from the slits 15, 15,. That is, an electric field is radiated from the annular waveguide antenna section 12 to the microwave introduction plate 4. When a current flows through the inner surface of the annular waveguide antenna section 12, the mode of the microwave propagating in the annular waveguide antenna section 12 is changed to a rectangular TE which is a basic propagation mode.
The size of the annular waveguide antenna unit 12 is determined in accordance with the microwave frequency of 2.45 GHz so as to make 10. The microwave in this mode is a single fundamental mode and propagates through the dielectric 14 in the annular waveguide antenna unit 12 with little loss of energy.

The circumferential length of a circle C (see FIG. 3) connecting the widthwise center of the annular waveguide antenna section 12 is determined by the wavelength of the microwave propagating in the annular waveguide antenna section 12. It is approximately an integral multiple. Therefore, the microwave resonates in the annular waveguide type antenna unit 12, and the above-mentioned standing wave becomes a high voltage / low current at the antinode position, and becomes a low voltage / high current at the node position. Is improved. That is, the amplitude of the standing wave formed in the antenna 11 increases, and the microwave having a high electric field intensity is passed through the slits 15, 15,.
Radiated to

FIG. 3 shows the slit 1 shown in FIGS.
It is explanatory drawing explaining 5, 15, .... As shown in FIG. 3, the rectangular (rectangular) slits 15, 15,... Have their lengths extending in the diametrical direction of the annular waveguide antenna unit 12, ie, inside the annular waveguide antenna unit 12. It is opened so as to be orthogonal to the traveling direction of the microwave propagating through.

Each of the slits 15, 15,...
An extension line L extending the center line in the longitudinal direction of
From the intersection point P _1, which is the side separated from the introduction portion 13, in the two directions along the circle C.
g / 4 (λg is the wavelength of the microwave propagating in the antenna), two slits 15, 15 are opened. From both slits 15, 15, in both directions along a circle C, Multiple other slits 1 at intervals of λg / 2
5, 15, ... have been established respectively. In this way, a plurality of regions having a strong electric field strength are formed on the dielectric 14 so as to be symmetrical with respect to the center of the ring of the annular waveguide antenna unit 12 and the longitudinal center line of the introduction unit 13 which is a rod. You.

Each of the above-mentioned slits 15, 15,... Is located between adjacent regions where the electric field intensity is strong, and an electric field of a strong electric field intensity leaks out from each of the slits 15, 15,. The light passes through the wave introduction plate 4 and is introduced into the processing container 1. That is, microwaves for generating plasma are introduced into the processing chamber 1. As described above, each slit 1
Are provided substantially radially on the cover member 10, so that the microwaves are uniformly introduced into the entire region in the processing container 1.

As shown in FIG. 1, the antenna 11 is provided on the cover member 10 having the same diameter as the processing container 1 without protruding from the periphery of the cover member 10.
Even if the diameter of the processing container 1 is large, the size of the plasma processing apparatus other than the processing container 1 can be reduced. Therefore, the plasma processing apparatus can be installed in a small space.

At substantially the center of the cover member 10, a pipe through hole is formed through the cover member 10 and the microwave introduction plate 4, and a gas introduction pipe 5 is attached to the tube through hole. A required gas is introduced into the processing chamber 2 from the gas introduction pipe. At the center of the bottom wall 1B of the processing chamber 2, a substrate holding table 3 on which the substrate W is placed is provided. Alternatively, an exhaust port 18 is provided in the bottom wall 1B of the processing container 1 so that the gas in the processing chamber 2 is exhausted from the exhaust port 18.

Referring to FIG. 4, the structure of the substrate holder 3 will be described in more detail. The central portion of the bottom wall 1B of the processing vessel 1 is hollowed out in a circular shape, and a cylindrical inner wall 1C having the same inner peripheral radius as the circular radius is formed on the upper side (the processing vessel 1 side) of the hollowed out circular portion. It is formed parallel to 1A. A ring-shaped insulating ring 31 is provided above the inner wall 1C. A base 32 is provided above the insulating ring 31. The vertically lower side of the base 32 is fitted into the insulating ring 31. A cooling water passage 38 is formed inside the base 32, and cooling water is supplied from a cooling water supply device (not shown).

On the base 32, there is provided an electrode 33 having a shape in which three disks having different radii are stacked with their central axes aligned. Large disk portion 3 having the largest radius at the bottom of electrode 33
The radius of 3A is substantially equal to the upper radius of the base 32. The electrode 33 further includes a middle disk portion 33B having a slightly smaller radius than the large disk portion 33A on the large disk portion 33A.
A small disk portion 33C having the smallest radius is provided on 3B.

The high frequency power supply 7 is connected to the electrode 33 via the matching box 16, and further the DC power supply 8 is connected. Therefore, the substrate W placed on the substrate holding table 3
A bias potential is generated, and the bias potential is controlled by controlling the power of the high-frequency power supply 7 to independently control the energy of ions in the plasma, thereby improving the processability (etching shape and the like) of the substrate W. it can. Alternatively, the electrode 33 also serves as an electrostatic chuck electrode for electrostatically attracting the substrate W to the substrate holding table 3.

The upper part of the insulating ring 31 and the base 32
In addition, a ring-shaped focus ring 30 is provided so as to surround the horizontal circumference of the large disk portion 33A and the middle disk portion 33B of the electrode 33, respectively.

The upper and side surfaces of the electrode 33 are covered with an insulating film 34. An upper surface 30A of the focus ring 30;
The ring-shaped upper surface 34A of the insulating film 34, which covers the ring-shaped upper surface 33D of the middle disk portion 33B of the electrode 33, is substantially flush.

On the ring-shaped upper surface 34A of the insulating film 34 covering the ring-shaped upper surface 33D of the middle disk portion 33B of the electrode 33 and on the inner edge of the upper surface 30A of the focus ring 30, three ring-shaped An edge ring 35 having a shape in which the thin plates are stacked with their central axes aligned is provided. The edge ring 35 is separate from the focus ring 30.

The inner peripheral radius of the vertically lowermost disk portion 35A of the edge ring 35 and the second lowermost disk portion 35B
Has the same length as the inner radius, and the outer radius of the disk portion 35A is longer than the outer radius of the disk portion 35B. Edge ring 3
5, the inner circumference radius of the uppermost disk portion 35C is equal to the disk portion 35B.
, The outer radius of the disk portion 35C is the same as the outer radius of the disk portion 35B. The inner peripheral side surfaces of the disk portion 35A and the disk portion 35B are both in contact with the insulating film 34.

The inner radius of the disk portion 35C is equal in length to the outer radius of the substrate W.
C, on the insulating film 34 existing on the upper surface
5C is placed inside in the horizontal direction.

When the edge ring 35 is formed of a semiconductor having a conductivity substantially equal to or higher than that of the substrate W, the edge ring 35 and the substrate W provided on the electrode 33 have substantially the same potential. The upper electric field does not concentrate on the outer peripheral portion of the substrate W, and becomes substantially uniform over the entire surface of the substrate W.

A cover component 36 separate from the focus ring 30 is disposed above the disc portion 35A and horizontally outside the disc portions 35B and 35C. Cover parts 3
6 has the same length as the outer radius of the disc portion 35B and the outer radius of the disc portion 35C, the outer radius of the cover component 36 is substantially equal to the outer radius of the focus ring 30,
Is equal to the sum of the thicknesses of the disk portion 35B and the disk portion 35C. A gap 37 is present outside the disc portion 35A in the horizontal direction, and the thickness of the gap 37 is equal to the thickness of the disc portion 35A. The gap 37 exists below the cover component 36 and vertically sandwiched between the cover component 36 and the focus ring 30. In addition,
The edge ring 35 and the cover component 36 may be made of the same material and integrally formed.

To perform, for example, an etching process on the surface of the substrate W using such a plasma processing apparatus, the exhaust port 1
After evacuating the inside of the processing chamber 2 to a desired pressure by evacuating from the chamber 8, a reaction gas is supplied from the gas introduction pipe 5 into the processing chamber 2.

Next, a microwave is oscillated from a microwave oscillator 20, and the oscillated microwave is transmitted through a waveguide 21 to an antenna 11.
To form a standing wave in the antenna 11. Due to this standing wave, the slits 15, 15,
The electric field radiated from the substrate passes through the microwave introduction plate 4 and is introduced into the processing chamber 2, and a uniform plasma is generated in the processing chamber 2, and the plasma uniformly etches the surface of the substrate W. .

The focus ring 30 is for preventing the high frequency electric field of the high frequency power applied to the electrode 33 by the high frequency power supply 7 from leaking in the direction of the side wall of the electrode 33, and effectively acting in the direction of the substrate W. It must be made of an insulator such as alumina (Al ₂ O ₃ ) having a thickness (width). On the other hand, the edge ring 35 is provided with a member having conductivity equal to or higher than that of the substrate W on the outer side in the horizontal direction of the substrate W, so that the outer periphery of the edge ring 35 (the disk portion 35B and the disk portion 35C). This is to prevent the electric field from being concentrated on the outer peripheral portion of the substrate W by causing the electric field to concentrate on the outer peripheral portion. This makes it possible to make the plasma irradiation uniform over the entire surface of the substrate W and to uniformly perform the plasma processing on the substrate W. Further, by disposing the edge ring 35, the electric field concentrated on the outer peripheral portion of the substrate W does not go around the electrode 33 to cause destruction, so that the life of the electrode 33 can be extended.

For example, the edge ring 35 is made of silicon (S
i), formed of a semiconductor such as silicon carbide (SiC). The edge ring 35 prevents the electric field from concentrating on the outer peripheral portion of the substrate W.
Of the electrode 33 (the insulating film 34 near the edge that covers the edge of the electrode 33 because the electrode 33 is covered with the insulating film). Become.

Since the cover component 36 is disposed above the focus ring 30 via the gap 37, the upper surface of the focus ring 30 formed of alumina (Al ₂ O ₃ ) is prevented from being sputtered by plasma. This prevents metal contamination (aluminum contamination) due to alumina (Al ₂ O ₃ ) on the upper surface of the substrate W. The cover component 36 is formed as thin as possible (preferably, 1 mm to 5 mm).

Further, a gap 37 is provided between the cover component 36 and the focus ring 30 so that heat given to the cover component 36 is prevented from being transmitted to the focus ring 30 and escaped as much as possible.

Thus, the heat capacity of the cover component 36 is reduced, and the cover component 36 itself is easily heated by plasma irradiation during the plasma processing of the substrate W. When the temperature of the cover component 36 is higher, the reaction product is less likely to adhere to the cover component 36 itself.

When the reaction product adheres to the cover component 36, the deposited reaction product is peeled off and becomes particles, which adheres as foreign matter on the substrate, and the product substrate becomes defective. It is necessary to prevent adhesion to the component 36.

The cover component 36 is formed of silicon (Si), silicon carbide (SiC), silicon oxide (SiO ₂ ), or the like, which does not cause contamination of the substrate W. Since the cover component 36 and the edge ring 35 are formed separately, the respective components can be easily manufactured.

A plasma processing apparatus (case A) including a silicon (Si) edge ring, a silicon carbide (SiC) cover part, and an alumina (Al ₂ O ₃ ) focus ring, and an edge ring and a cover part The substrate was treated with a plasma processing apparatus (case B) equipped with a focus ring made of alumina (Al ₂ O ₃ ) without a substrate, and a comparative experiment was performed.

The conditions of the comparative experiment are as follows. Experimental substrate: silicon (Si) wafer (bare wafer) Processing chamber pressure: 20 mTorr Microwave (2.45 GHz) power: 1.6 kW RF (400 kHz) power: 1.4 kW Processing gas: Ar gas (flow rate 320 sccm) Processing time: 120 seconds

After the above treatment, the aluminum contamination on the wafer was analyzed by the atomic absorption method. As a result, the alumina on the wafer surface after the treatment was as follows: Case A: Aluminum 5 × 10 ¹² atoms / cm ² Case B: Aluminum It was 5 × 10 ¹³ atoms / cm ² . Therefore, it is understood that aluminum contamination is reduced in case A.

[0057]

As described above, according to the present invention, an edge ring having the same or higher conductivity as the substrate is provided outside the substrate, and a gap is provided outside the edge ring and above the focus ring. Since the cover parts were provided through
It is possible to prevent the concentration of an electric field from occurring on the outer peripheral portion of the substrate, realize uniform processing of the substrate, and reduce metal contamination of the substrate due to sputtering of the surface of the focus ring.

Further, since the reaction products can be prevented from adhering to the cover component itself, particles generated by the separation of the reaction products can be reduced. Further, if an antenna having an annular tubular member and a slit plate provided with a slit is provided, parts of the apparatus other than the processing container can be miniaturized.

[Brief description of the drawings]

FIG. 1 is a schematic front sectional view of a plasma treatment apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic front view of the plasma processing apparatus shown in FIG.

3 is an explanatory view of a slit of a cover member of the plasma processing apparatus shown in FIG.

FIG. 4 is a schematic view of a substrate holder of the plasma processing apparatus shown in FIG.

FIG. 5 is a schematic front sectional view of a conventional microwave plasma processing apparatus.

FIG. 6 is a schematic plan view of a conventional microwave plasma processing apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Processing container 1A Side wall 1B Bottom wall 1C Inner wall 2 Processing chamber 3 Substrate holder 4 Microwave introduction plate 5 Gas introduction pipe 6 Gas nozzle 7 High frequency power supply 8 DC power supply 10 Cover member 11 Antenna 12 Ring waveguide antenna section 13 Introduction section Reference Signs List 13A Inlet 14 Dielectric 15 Slit 18 Exhaust port 20 Microwave transmitter 21 Waveguide 30 Focus ring 31 Insulating ring 32 Base 33 Electrode 33A Large disc part 33B Middle disc part 33C Small disc part 33D Upper surface 34 Insulation Membrane 34A Upper surface 35 Edge ring 35A-C Disk portion 36 Cover part 37 Gap 38 Cooling channel C circle L Extension line P ₁ intersection W Substrate

Continued on the front page F term (reference) 4K030 CA04 DA04 FA01 GA02 KA14 KA20 KA30 KA32 KA45 KA46 4K057 DA20 DD01 DM06 DM18 DM29 DN01 5F004 AA16 BA20 BB11 BB23 BB29 BD01 BD04 DA23

Claims (4)

[Claims] An electrode to which a high-frequency power is applied and on which a substrate as an object to be processed is mounted; a focus ring of an insulator disposed around the electrode so as to surround the electrode; An edge ring formed of a material having the same or higher conductivity as the substrate and disposed outside the substrate on which the substrate is placed; and a gap disposed outside the edge ring and above the focus ring. And a cover component disposed through the cover ring, wherein the cover component is configured to prevent the plasma from being irradiated to the focus ring, and is formed of a material that does not cause contamination to the substrate. Substrate holding table. 2. The semiconductor device according to claim 1, wherein said edge ring is formed of silicon (Si) or silicon carbide (SiC), and said cover component is formed of silicon (Si), silicon carbide (SiC) or silicon oxide (SiO ₂ ). The substrate holder according to claim 1, wherein: 3. A substrate holder according to claim 1 or 2, a processing chamber provided with the substrate holder, and having a gas supply port for supplying a reaction gas; A microwave introducing means for introducing a wave; a plasma processing apparatus. 4. The microwave introduction means: a microwave introduction plate for sealing the processing chamber and transmitting the microwave; and a microwave introduction plate attached to a surface of the microwave introduction plate opposite to the processing chamber. An annular tubular member for transmitting the microwave, the inlet for introducing the microwave being opened on a peripheral side surface; and the tubular member and the microwave between the tubular member and the microwave introduction plate. 4. The plasma processing apparatus according to claim 3, further comprising: a slit plate disposed opposite to the wave introduction plate and having a predetermined slit through which the microwave passes.