JP4246592B2 - Dry etching equipment - Google Patents

Description

  The present invention relates to a dry etching apparatus that enables high selective etching of silicon and silicon oxide.

Conventionally, there is a plasma etching apparatus using silicon as a material for an anode electrode (see Patent Documents 1 and 2).
By using such a plasma etching apparatus using silicon as an anode electrode, high-selectivity etching of SiO ₂ / Si is possible in the processing of silicon oxide using silicon as a mask material.

  Here, the plasma etching apparatus will be briefly described. As shown in FIG. 3, this plasma etching apparatus is a parallel plate type in which a metal chamber 301 is provided with an anode electrode 302 made of silicon and a cathode electrode 303 on which a substrate W to be processed is placed. It is a device. A high frequency can be applied to the anode electrode 302 by a high frequency power source 304, and the cathode electrode 303 is set to a ground potential.

  An etching gas is introduced from the gas introduction port 305, and the introduced gas is supplied to a space between the anode electrode 302 and the cathode electrode 303 through a plurality of holes provided in the anode electrode 302. Further, the inside of the chamber 301 is exhausted by an exhaust means (not shown) communicating with the exhaust port 306 so that a predetermined pressure (degree of vacuum) is obtained.

In the apparatus shown in FIG. 3, first, the chamber 301 is evacuated to a desired pressure, and then, for example, CF ₄ gas is introduced from the gas inlet 305, and a predetermined amount is provided between the anode electrode 302 and the cathode electrode 303. It is assumed that CF ₄ gas having a pressure of 1 is introduced. In this state, a high frequency of 13.56 MHz is applied from the high frequency power source 304 to the anode electrode 302, whereby the introduced CF ₄ gas plasma is generated between the anode electrode 302 and the cathode electrode 303.

  When the plasma is generated in this way, a plasma potential Vp of about several tens of eV is induced in both the anode electrode 302 and the cathode electrode 303, whereby the surface of the substrate W placed on the cathode electrode 303 is It will be etched. Here, since the plasma potential Vp is also induced in the anode electrode 302, the anode electrode 302 is also etched (sputtered), and silicon atoms constituting the anode electrode 302 are released into the plasma.

Part of the Si atoms released into the plasma in this way is combined with F atoms in the CF ₄ gas plasma to become SiF _n (n = 1, 2, 3, 4), and exhausted from the exhaust port 306. And removed from the inside of the chamber 301. Thus, the CF ₄ gas in the plasma being generated, F atoms decreases an etching species Si, an SiO ₂ etching species CF _n ⁺ _(n = 1,2,3) and CF _n (N = 1, 2, 3) radicals remain and are transported to the substrate W side, and contribute to etching on the substrate W.
As a result, SiO ₂ is selectively etched on the substrate W.

The applicant has not yet found prior art documents related to the present invention by the time of filing other than the prior art documents specified by the prior art document information described in this specification.
JP-A-8-107102 Japanese Patent Laid-Open No. 10-070105

However, some of the Si atoms sputtered by the plasma and jumped out of the anode electrode 302 reach the substrate W, and adhere to and accumulate on the surface to be etched of the substrate W. As a result, in the conventional apparatus shown in FIG. 3, for example, the deposited Si is used as a mask to be etched in a state different from the intended purpose, and the high selective etching of SiO ₂ / Si is hindered. The problem occurs.

The present invention has been made to solve the above-described problems, and enables high-selectivity etching of SiO ₂ / Si to be realized in a state where the influence on the substrate to be processed is suppressed. With the goal.

  A dry etching apparatus according to the present invention is disposed outside a surface of a plasma generation chamber in which plasma of a gas introduced into the chamber is generated, and supplies high frequency power to the plasma generation chamber. A high-frequency coil, a high-frequency power source that applies a high-frequency current to the high-frequency coil, a processing chamber that communicates with the plasma generation chamber via a communication hole, and an exhaust port of the processing chamber that communicates with the plasma generation chamber and the processing chamber. An evacuation unit that depressurizes the inside, a substrate stage on which a substrate to be processed is placed on a surface facing the communication hole of the processing chamber, a first power source that applies a potential to the substrate stage, and an inside of the plasma generation chamber At least a Si electrode made of a material containing Si and a second power source for applying a potential to the Si electrode, the Si electrode being other than the surface on which the high-frequency coil is arranged It is obtained as being located inside the surface of the plasma generation chamber.

In this apparatus, when plasma is generated in the plasma generation chamber, Si atoms sputtered from the Si electrode due to the impact of ions in the plasma are released into the plasma. As a result, F radicals in the plasma drawn out from the communication hole to the processing chamber are combined with the released Si atoms to become SiF _n (n = 1, 2, 3, 4).

  In the dry etching apparatus, the Si electrode may be disposed on the surface facing the communication hole in the plasma generation chamber. Further, the high frequency coil may be arranged outside the surface facing the communication hole in the plasma generation chamber.

  Another dry etching apparatus according to the present invention supplies a high-frequency power to a plasma generation chamber in which a plasma of a gas introduced into the plasma generation chamber is generated and outside of any surface of the plasma generation chamber. A high-frequency coil for applying a high-frequency current to the high-frequency coil, a processing chamber communicating with the plasma generation chamber via a communication hole, and a plasma generation chamber and a process communicating with the exhaust port of the processing chamber An exhaust means for reducing the pressure inside the chamber, a substrate stage on which a substrate to be processed is placed on a surface facing the communication hole of the processing chamber, a first power source for applying a potential to the substrate stage, and a communication with the substrate stage It includes at least a Si electrode disposed in the processing chamber between the hole and a second power source for applying a potential to the Si electrode, and the Si electrode is made of a material containing Si. One in which the.

In this apparatus, plasma is generated in the plasma generation chamber, and the generated plasma is drawn out from the communication hole to the processing chamber. When the plasma is drawn out to the processing chamber side, Si atoms sputtered from the Si electrode by the impact of ions in the plasma are released into the plasma. As a result, the F radicals in the plasma are combined with the released Si atoms to become SiF _n (n = 1, 2, 3, 4).

  In the dry etching apparatus described above, the first power source and the second power source are power sources for applying a high-frequency bias, and the high frequency power source, the first power source, and the second power source have different frequencies of power to be supplied. By doing so, plasma is generated more stably.

As described above, according to the present invention, since the plasma generation chamber and the processing chamber are provided, the atoms sputtered by the plasma and jumped out of the Si electrode reach the substrate stage on which the substrate is placed. To be suppressed. As a result, according to the present invention, high selective etching of SiO ₂ / Si can be realized in a state in which the influence on the substrate, such as the atoms protruding from the Si electrode being attached to the substrate to be processed, is reduced. An excellent effect is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment 1]
FIG. 1 is a schematic cross-sectional view showing a configuration example of a dry etching apparatus according to the first embodiment of the present invention. The dry etching apparatus shown in FIG. 1 includes a plasma generation chamber 101 and a processing chamber 102, and a high frequency coil 106 for forming an electric field in the plasma generation chamber 101 is provided around the plasma generation chamber 101. Yes. The side part of the plasma generation chamber 101 is made of an insulating material (dielectric material). A high frequency induction current is passed through the high frequency coil 106 by a high frequency power source 107.

  The plasma generation chamber 101 and the processing chamber 102 communicate with each other through a communication hole 108, and the processing chamber 102 is provided with a substrate stage 109 on which a substrate W to be processed is placed. For example, the substrate stage 109 is arranged at a distance of about 20 cm from the communication hole 108. A high frequency can be applied to the substrate stage 109 by a high frequency power source 110. In addition, the plasma generation chamber 101 is provided with a gas inlet 111 for introducing an etching gas, and a vacuum pump (exhaust means) 113 communicates with the processing chamber 102 via an exhaust port 112.

  In addition, in the apparatus of FIG. 1, a Si electrode 114 to which a bias is applied by a high frequency power supply 115 is disposed inside the plasma generation chamber 101. In the apparatus shown in FIG. 1, the Si electrode 114 is disposed on the upper surface of the plasma generation chamber 101 that is a surface facing the communication hole 108. The arrangement of the Si electrode 114 is not limited to the configuration shown in FIG. 1, and the Si electrode 114 may be arranged on the inner surface of the plasma generation chamber 101 other than the surface on which the high-frequency coil 106 is arranged.

  The Si electrode 114 is composed of, for example, a bias application electrode portion made of a metal material and a high-purity single crystal silicon structure fixed to the electrode portion. The Si electrode 114 only needs to be configured so that a bias supplied from the high-frequency power source 115 can be applied to the portion of single crystal silicon to be sputtered. In the apparatus shown in FIG. 1, the Si electrode 114 is composed of a single crystal silicon disk and a bias application electrode, a single crystal silicon disk is disposed on the side of the communication hole 108, and the single crystal silicon disk Between the upper surface of the plasma generation chamber 101, the above-described bias application electrode is disposed.

In the case where the portion that is sputtered and emits Si atoms is a semiconductor such as single crystal silicon, the high frequency power supply 115 may be a DC power supply, and a DC bias is applied to the sputtered single crystal silicon. May be.
Note that the portion of the Si electrode 114 that is sputtered and emits Si atoms is not limited to single crystal silicon, but may be made of a material containing Si, and may be made of silicon carbide or silicon nitride.

In the apparatus shown in FIG. 1, first, the inside of the processing chamber 102 and the plasma generation chamber 101 is evacuated by a vacuum pump 113 to a desired pressure (about 10 ⁻⁴ to 10 ⁻⁵ Pa), and then the gas introduction port For example, CF ₄ gas is introduced into the plasma generation chamber 101 from 111, and the inside of the plasma generation chamber 101 is maintained at a pressure of about 10 ⁻¹ to 10 ⁻² Pa.

In this state, when a high frequency induction current is supplied from the high frequency power source 107 to the high frequency coil 106 and a high frequency electric field is applied to the inside of the plasma generation chamber 101, plasma 120 is generated inside the plasma generation chamber 101. When CF ₄ gas is used as an etching gas, plasma composed of CF _n ⁺ (n = 1, 2, 3), CF _n (n = 1, 2, 3) radicals, and F atoms (F radicals) is generated. . A radical (free radical) is an atom or molecule having an unpaired electron and is an active species having a high chemical activity.

When a high frequency electric field is applied to the Si electrode 114 by the high frequency power supply 115 in a state where the plasma 120 is generated in this way, CF _n ⁺ (n = 1, 2, 3) ions in the plasma 120 are directed toward the Si electrode 114. Accelerated. The Si electrode 114 is sputtered by the accelerated CF _n ⁺ (n = 1, 2, 3) ions, and Si atoms are released from the Si electrode 114. A part of the Si atoms released into the plasma in this way is combined with F atoms in the plasma 120 to form SiF _n (n = 1, 2, 3, 4). It is exhausted from the exhaust port 112 via and is removed from the inside.
Thus, in the plasma 120 which is generated in the plasma generation chamber 101, F atoms decreases an etching species ^{_{Si, CF n + (n =}} 1,2,3 is an etching species SiO ₂ ) And CF _n (n = 1,2,3) radicals remain.

On the other hand, the generated plasma 120 is drawn out toward the processing chamber 102 having a lower pressure than the plasma generation chamber 101 and flows toward the substrate stage 109. When a high frequency is applied from the high frequency power supply 110 to the substrate stage 109, ions and electrons in the plasma generated in the plasma generation chamber 101 are moved in the direction of the substrate stage 109 by an electric field formed on the substrate stage 109. Transported. As a result, the CF _n ⁺ (n = 1, 2, 3) and CF _n (n = 1, 2, 3) radicals remaining in the plasma as described above were placed on the substrate stage 109. This contributes to etching on the substrate W, and can realize high selective etching of SiO ₂ / Si.

Here, the state on the surface of the substrate W will be described by taking as an example a case where a SiO ₂ film is formed on the substrate W to be processed and this film is etched using a mask pattern made of silicon.
As is well known, on the surface of the substrate W, CF _n (n = 1, 2, 3) radicals, which are precursors to be polymerized films, are transported. At the same time, since a high frequency is applied to the substrate stage 109 by the high frequency power supply 210, the surface of the substrate W is also subjected to the impact of CF _n ⁺ (n = 1, 2, 3) ions.

By this ion bombardment, oxygen is generated from the SiO ₂ film on the surface of the substrate W. For this reason, CF _n (n = 1, 2, 3) radicals transported to the surface of the substrate W are combined with the generated oxygen to become COF _n (n = 1, 2, 3), and are exhausted in a gaseous state. Will be. Therefore, on the surface of the SiO ₂ film on the substrate W, polymer deposition due to the radicals does not occur, and smooth etching proceeds.

Further, since F atoms which are Si etchants are removed from the plasma flowing to the substrate W, the Si mask pattern formed on the SiO ₂ film is hardly etched. Further, since the generation of oxygen as described above does not occur on the surface of the Si mask pattern, the flying CF _n (n = 1, 2, 3) radicals are polymerized to form a polymer film such as fluorocarbon. CF _n ⁺ (n = 1, 2, 3) ions flying into the Si mask pattern are consumed for etching these polymer films. Also in this respect, the Si mask pattern is hardly etched.

As described above, according to the dry etching apparatus shown in FIG. 1, Si is hardly etched, and SiO ₂ is selectively etched with a high selection ratio. In addition, according to the apparatus of FIG. 1, since the plasma generation chamber 101 and the processing chamber 102 are separated, a part of Si atoms sputtered by the plasma and jumped out of the Si electrode 114 reach the substrate W. It rarely happens. As a result, the above-described problem caused by the conventional apparatus shown in FIG. 3 is solved by the apparatus shown in FIG.

  By the way, in the apparatus shown in FIG. 1, the three high frequency power sources 107, 110, and 115 are operated, plasma is generated, the Si electrode 114 is sputtered, ions in the direction of the substrate stage 109, etc. We are transporting. When power of the same frequency is supplied from these three power sources, there is a case in which negotiations are made with each other, for example, discharge in the plasma generation chamber 101 becomes unstable, and a problem such that a desired bias voltage cannot be controlled may occur. is there.

  On the other hand, the power supplied from the high-frequency power source 107 is 13.56 MHz, the power supplied from the high-frequency power source 110 is 2 MHz, and the power supplied from the high-frequency power source 115 is 200 KHz. A desired bias voltage can be controlled. As described above, in the dry etching apparatus shown in FIG. 1, it is preferable that the frequencies of the power supplied from the three power sources are different from each other. The same applies to the apparatus shown in FIG. 2 described later.

[Embodiment 2]
Next, a second embodiment of the present invention will be described. FIG. 2 is a schematic cross-sectional view showing a configuration example of a dry etching apparatus according to the second embodiment of the present invention. The dry etching apparatus shown in FIG. 2 includes a plasma generation chamber 201 and a processing chamber 202, and a high frequency coil 206 for forming an electric field in the plasma generation chamber 201 is provided around the plasma generation chamber 201. Yes. The side part of the plasma generation chamber 201 is made of an insulating material (dielectric material). A high frequency induction current is passed through the high frequency coil 206 by a high frequency power source 207.

  The plasma generation chamber 201 and the processing chamber 202 communicate with each other through a communication hole 208, and the processing chamber 202 is provided with a substrate stage 209 on which a substrate W to be processed is placed. For example, the substrate stage 209 is arranged at a distance of about 20 cm from the communication hole 208. A high frequency can be applied to the substrate stage 209 by a high frequency power supply 210. The plasma generation chamber 201 is provided with a gas introduction port 211 for introducing an etching gas, and a vacuum pump (exhaust means) 213 communicates with the processing chamber 202 via an exhaust port 212.

  In addition, in the apparatus shown in FIG. 2, a high-frequency power source in which a Si electrode 214 made of high-purity silicon is disposed between the communication hole 208 and the substrate stage 209 and a high-frequency electric field (bias) is applied to the Si electrode 214. 215 is provided. The Si electrode 214 is composed of, for example, a bias application electrode portion made of a metal material and a single crystal silicon structure fixed to the electrode portion. The Si electrode 214 may be configured so that a bias supplied from the high-frequency power source 215 can be applied to a portion of single crystal silicon to be sputtered.

In addition, in the case where the portion that is sputtered and emits Si atoms is a semiconductor such as single crystal silicon, the high frequency power source 215 may be a DC power source, and a DC bias is applied to the sputtered single crystal silicon. May be.
Further, the portion of the Si electrode 214 that is sputtered to release Si atoms is not limited to single crystal silicon, but may be made of a material containing Si, and may be made of silicon carbide or silicon nitride.

  In the configuration example shown in FIG. 2, the Si electrode 214 is disposed in the vicinity of the communication hole 208 inside the processing chamber 202 and has a shape in which the cylinder is narrowed toward the substrate stage 209 (downward). In other words, the single crystal silicon structure constituting the Si electrode 214 has a shape obtained by partially cutting a cylinder that narrows in the direction of the substrate stage 209. Note that the Si electrode 214 (single-crystal silicon structure) may be a cylinder, or the cylinder may be widened toward the substrate stage 209.

First, the Si electrode 214 needs to be disposed in a space between the communication hole 208 and the substrate stage 209. The Si electrode 214 needs to be arranged in a state where plasma drawn from the communication hole 208 toward the processing chamber 202 can act.
Further, the Si electrode 214 is arranged so that the number of atoms emitted from the Si electrode 214 (single crystal silicon structure) by the action of plasma and scattered toward the substrate stage 209 is reduced. It is desirable.

  The particles sputtered from the Si electrode 214 are emitted according to the COSINE rule (reference: “Basics of sputtering”, published by the University of Tokyo). Therefore, if the surface to be sputtered of the Si electrode 214 is not facing the substrate stage 209 and parallel to the surface of the substrate stage 209, the substrate is sputtered from the Si electrode 214 as compared with the parallel plate type apparatus shown in FIG. The number of particles reaching the stage 209 can be reduced.

  In consideration of the COSINE rule, it is better to set the shape and arrangement of the Si electrode 214 such that the extended portion of the surface to be sputtered of the Si electrode 214 is outside the substrate stage 209. . For example, the Si electrode 214 having a shape narrowed in the direction of the substrate stage 209 may be used, and the Si electrode 214 may be disposed with the center of the opening of the Si electrode 214 aligned with the center of the communication hole 208. This is almost the state shown in FIG. With this configuration, it is possible to substantially suppress particles sputtered and emitted from the Si electrode 214 from reaching the substrate stage 209.

Next, the operation of the dry etching apparatus shown in FIG. 2 will be described. In the following, a case where a SiO ₂ film is formed on the substrate W to be processed and this film is etched with a mask pattern made of silicon is taken as an example.
First, the inside of the processing chamber 202 and the plasma generation chamber 201 is evacuated to a desired pressure (about 10 ⁻⁴ to 10 ⁻⁵ Pa) by a vacuum pump 213, and then an etching gas is plasma from a gas introduction port 211. It introduce | transduces in the production | generation chamber 201, and the inside of the plasma production chamber 201 is maintained at the pressure of about 10 ^{< -1} > -10 ^<-2 > Pa.

In such a state, when a high frequency current is passed from the high frequency power supply 207 to the high frequency coil 206 and a high frequency electric field is applied to the inside of the plasma generation chamber 201, an etching gas plasma 220 is generated in the plasma generation chamber 201. When CF ₄ gas is used as an etching gas, a plasma 220 composed of CF _n ⁺ (n = 1, 2, 3), CF _n (n = 1, 2, 3) radicals, and F atoms (F radicals) is generated. The Here, the processing chamber 202 that is directly evacuated and decompressed by the vacuum pump 213 has a lower pressure than the plasma generation chamber 201. As a result, the plasma generated as described above is drawn to the processing chamber 202 side, and the drawn plasma flows toward the substrate stage 209.

In these states, when a high frequency electric field (bias) is applied to the Si electrode 214 by the high frequency power source 215, ions in the plasma extracted from the communication hole 208 are attracted to the Si electrode 214 and cause sputtering. As a result, the Si electrode 214 emits Si atoms. Thus, the Si atoms released from the Si electrode 214 are mixed into the plasma drawn out from the communication hole 208 and combined with the F atoms in the plasma, and SiF _n (n = 1, 2, 3, 4). )

This SiF _n is exhausted from the exhaust port 212 and removed from the inside of the processing chamber 202. As a result, in the plasma drawn out from the communication hole 208 and flowing in the direction of the substrate stage 209, F atoms decrease, and CF _n ⁺ (n = 1, 2, 3) and CF _n (n = 1, 1). 2,3) The radical becomes dominant. When a high frequency is applied from the high frequency power supply 210 to the substrate stage 209, ions and electrons in the plasma are transported in the direction of the substrate stage 209 by an electric field formed on the substrate stage 209.

Therefore, CF _n ⁺ (n = 1, 2, 3) and CF _n (n = 1, 2, 3) radicals are mainly transported to the surface of the substrate W fixed on the substrate stage 209, As a result, the SiO ₂ film is selectively etched. On the other hand, in the apparatus shown in FIG. 2, since the surface of the Si electrode 214 that receives ion bombardment (sputtering) faces the communication hole, Si electrons emitted from the Si electrode 214 are emitted from the substrate stage 209. Never fly in the direction.

Further, according to the dry etching apparatus shown in FIG. 2, since the Si electrode 214 is not inside the plasma generation chamber 201, atoms jumping out from the sputtered Si electrode 214 adhere to the inner wall of the plasma generation chamber 201 and form a film. Since the formation is suppressed, the supply of high-frequency power is not hindered.
As described above, according to the dry etching apparatus shown in FIG. 2, high selective etching of Si and SiO ₂ can be performed.

  In the above description, plasma is generated in the plasma generation chamber by applying a high-frequency electric field to the inside of the plasma generation chamber by the high-frequency coil provided around the side of the plasma generation chamber. It is not limited. For example, the upper surface of the plasma generation chamber facing the communication hole communicating with the processing chamber may be made of an insulating material (dielectric material), and a spiral coil may be provided here.

  Even in this configuration, a high-frequency electric field can be applied to the inside of the plasma generation chamber by flowing a high-frequency induction current through the spiral coil. As a result, plasma can be generated inside the plasma generation chamber. However, in the plasma generation chamber having such a configuration, when the Si electrode is placed inside the plasma generation chamber, it is disposed other than the upper surface of the plasma generation chamber.

It is typical sectional drawing which shows the structural example of the dry etching apparatus in embodiment of this invention. It is typical sectional drawing which shows the other structural example of the dry etching apparatus in embodiment of this invention. It is typical sectional drawing which shows the structure of the conventional dry etching apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 ... Plasma generation chamber, 102 ... Processing chamber, 106 ... High frequency coil, 107 ... High frequency power supply, 108 ... Communication hole, 109 ... Substrate stage, 110 ... High frequency power supply, 111 ... Gas introduction port, 112 ... Exhaust port, 113 ... Vacuum Pump, 114 ... Si electrode, 115 ... high frequency power source, 120 ... plasma.

Claims (5)

A plasma generation chamber in which plasma of a gas introduced into the chamber is generated;
A high-frequency coil disposed outside any surface of the plasma generation chamber for supplying high-frequency power to the inside of the plasma generation chamber;
A high frequency power source for applying a high frequency current to the high frequency coil;
A processing chamber communicating with the plasma generation chamber via a communication hole;
Exhaust means for reducing the pressure inside the plasma generation chamber and the processing chamber in communication with the exhaust port of the processing chamber;
A substrate stage on which a substrate to be processed is placed on a surface of the processing chamber facing the communication hole;
A first power source for applying a potential to the substrate stage;
An Si electrode that is disposed inside the plasma generation chamber and is made of a material containing Si;
A second power source for applying a potential to the Si electrode;
The dry etching apparatus, wherein the Si electrode is disposed inside a surface of the plasma generation chamber other than a surface where the high-frequency coil is disposed. The dry etching apparatus according to claim 1,
The dry etching apparatus, wherein the Si electrode is disposed on a surface facing the communication hole in the plasma generation chamber. The dry etching apparatus according to claim 1,
The high frequency coil is disposed outside a surface facing the communication hole in the plasma generation chamber. A plasma generation chamber in which plasma of a gas introduced into the chamber is generated;
A high frequency coil disposed outside any surface of the plasma generation chamber for supplying high frequency power to the plasma generation chamber;
A high frequency power source for applying a high frequency current to the high frequency coil;
A processing chamber communicating with the plasma generation chamber via a communication hole;
Exhaust means for reducing the pressure inside the plasma generation chamber and the processing chamber in communication with the exhaust port of the processing chamber;
A substrate stage on which a substrate to be processed is placed on a surface of the processing chamber facing the communication hole;
A first power source for applying a potential to the substrate stage;
An Si electrode disposed inside the processing chamber between the substrate stage and the communication hole;
A second power source for applying a potential to the Si electrode;
The dry etching apparatus, wherein the Si electrode is made of a material containing Si. In the dry etching apparatus according to any one of claims 1 to 4,
The first power source and the second power source are power sources for applying a high-frequency bias,
The dry etching apparatus, wherein the high-frequency power source, the first power source, and the second power source have different frequencies of power to be supplied.

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