JP2002184756A - Plasma processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the consumption of the susceptor of an electrode for supporting a wafer and the consumption of the cover of the electrode to thereby elongate their lives, and to prevent foreign matters from being produced. SOLUTION: In a plasma processing apparatus for processing a specimen by applying a high frequency bias to it, a protective member which is made of an insulating material and protects a specimen base from plasma damage, and an annular member which is made of a conductive material and to which the high frequency bias is applied, as is the specimen, are disposed on the outer peripheral surface of the specimen supporting surface of the specimen base, and a high frequency resistance member made of an insulating material is disposed on the outermost peripheral side surface of the annular member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plasma processing apparatus, and more particularly to a plasma processing apparatus suitable for a plasma etching process.

[0002]

2. Description of the Related Art Silicon oxide films (hereinafter simply referred to as "oxide films")
) Or an insulating film such as a silicon nitride film or a film made of a low dielectric constant material (a so-called Low-k material).
Conventional techniques relating to an etching apparatus and an etching method for these are collectively referred to as an “insulating film”.
As described in JP-A-114444, sputter etching using freon gas as a main etching gas is basically performed. In addition, as the etching gas, a gas species composed of fluorine, carbon, hydrogen, oxygen, etc. diluted with argon is generally used, and various etching methods using these etching gas species with an optimal composition have been proposed. ing.

[0003] Etching of an oxide film proceeds by reacting silicon with fluorine to form silicon fluoride, but requires selective etching of polysilicon or silicon nitride which is the base of the oxide film. Therefore, the oxide film etching proceeds, but the etching of the underlying material must be stopped. One solution is to etch with CF radicals and ions. On the surface of the oxide film, fluorine F in the CF radical reacts with silicon and is vaporized. Further, carbon C of the CF radical reacts with oxygen in the oxide film and is removed. On the other hand, on the surface of the polysilicon or silicon nitride film, fluorine F and silicon in the CF radical react with each other and vaporize, but since these films do not contain an element which reacts with carbon C and vaporizes, carbon C remains on the surface as a deposited film. Etching is suppressed by the deposited film, and selective etching of the oxide film and the base material can be performed.

In the oxide film etching, since such an etching mechanism is used, CF radicals,
It is important to control F radicals and ions. Generally, since the F radicals in the plasma become excessive, a method has been proposed in which the F radicals are forcibly consumed (scavenged) and controlled. For example, as described in Japanese Patent No. 2519383, in a plasma etching of an oxide film formed on a silicon nitride film, there is a method of installing a silicon material in a processing chamber in order to scavenge F radicals. In addition, JP-A-63-9120 discloses that
It is disclosed to place a scavenge material on the wafer stage for radicals that etch the resist. Japanese Patent Application Laid-Open No. Hei 5-234696 discloses a method in which a silicon nitride, which is a scavenging material, is provided on the outer periphery of a wafer to apply a bias. Regarding bias application, as disclosed in Japanese Patent Application Laid-Open No. 5-335283, there is known a method in which a conductor (lower resistance than the wafer, for example, SiC, carbon) is provided around the wafer to make the bias uniform. ing. As described above, it is widely known that a material that scavenges F radicals is provided on an electrode or the like. However, as for a method of applying a bias to a scavenging material or a conductor member provided around the electrode, it is simply disclosed that bias is applied. There is only.

[0005]

In the above-mentioned prior art, no special consideration has been given to the wear and the generation of foreign matter due to the application of a bias to the conductor and the scavenge material provided on the outer peripheral portion of the wafer mounting surface.

[0006] That is, when a conductor member or a scavenge member is placed on an electrode and a bias is applied, ions are incident on these members. However, the incident ions are incident not only on the upper surfaces of these members but from all directions. That is, ions are incident not only in the direction perpendicular to the surface of the sample stage but also in the direction inside the surface of the sample stage (in the direction of the wall surface of the processing chamber) if conditions are met. Therefore, it is conceivable to provide a cover made of an insulating material in order to limit the incidence of ions on these members. However, normally, a high-frequency bias is also applied to the surface of the cover, and the cover is worn out by ion irradiation, and a deposit may be attached to another portion by sputtering to generate foreign matter. Therefore, in consideration of these, it is necessary to suppress the consumption of the members installed on the outer peripheral portion of the wafer mounting surface to extend the life and to provide a structure of the electrode peripheral portion in which the generation of foreign matters is suppressed.

An object of the present invention is to suppress the amount of ions incident on a sample stage supporting a wafer, to prevent the sample stage from being sputtered and consumed, and to prevent the sputtered film adhered to the inner wall of the plasma processing apparatus. An object of the present invention is to provide a plasma processing apparatus capable of preventing a source of foreign matter from being generated and improving the life of components and the operation rate of the plasma processing apparatus.

[0008]

The object of the present invention is to hold a sample electrostatically on an electrode provided in a processing chamber, and apply a high-frequency bias to the sample independently of generation of plasma in the processing chamber to cause the sample to be removed. In a plasma processing apparatus for processing, an annular member having an annular plasma component adjusting function is positioned on the outer periphery of a sample on a dielectric film for electrostatic adsorption provided on an electrode, and the annular member is statically placed on the electrode. This can be achieved by arranging the high-frequency resistance member on the outer peripheral end surface of the annular member while arranging the high-frequency resistance member so as to be capable of being held by electroadsorption.

The above object is also achieved by providing a vacuum processing chamber, a sample stage on which a sample to be processed in the vacuum processing chamber is mounted, gas supply means for supplying a plasma generation gas into the vacuum processing chamber, In a plasma processing apparatus having plasma generating means for converting a gas supplied into a processing chamber into plasma, and bias applying means for applying a high-frequency bias to a sample independently of the plasma generating means, the sample stage has a substantially flat surface for supporting the sample. A protective member made of an insulator for protecting the sample table from plasma damage and an annular member made of a conductor are installed on the outer peripheral surface. A high-frequency circuit is formed such that a high-frequency bias is also applied to the annular member when a bias is applied, and a high-frequency resistance member made of an insulating material is provided on the outermost peripheral side surface of the annular member By installing, it is achieved.

That is, an annular member (scavenge member) such as silicon, which is replaceable and made of a conductor, is provided on the outer periphery of the sample stage.
Is installed, and a bias is applied to the annular member at the same time as applying a bias to the sample (wafer). Further, a high frequency resistance member (susceptor) made of an insulating material such as quartz is provided on the outer peripheral portion of the annular member. This high-frequency resistance member has an arrangement or structure that covers the outer peripheral side surface of the annular member, and is installed so that the high-frequency impedance between the annular member and the inner wall of the plasma processing chamber is increased.

Further, a cover (electrode cover) is provided below the high-frequency resistance member so that even if the electrode moves up and down, a reactive substance or plasma does not flow inside the electrode. That is, a plurality of cylindrical covers having different diameters are placed one on top of the other so as to prevent the cover function from being impaired even if the electrodes move up and down.
The end face of the cover is made to enter the inside of the high-frequency resistance member made of quartz or the like so as not to be directly exposed to plasma.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing a configuration of a plasma etching apparatus to which the present invention is applied, which is a plasma processing apparatus to which electron cyclotron resonance is applied.

A coil 2 for generating a magnetic field for electron cyclotron resonance (ECR) is provided around an etching chamber 1 as a vacuum vessel. The etching chamber 1 is provided in an upper opening of the vacuum chamber 15, and a wafer mounting electrode attached to a lower part of the vacuum chamber 15 is located in the vacuum chamber. A gas supply plate 4 is provided above the etching chamber 1 so as to face the wafer mounting electrode. The etching gas is supplied through a gas supply pipe 3 and is supplied from a gas supply plate 4 made of silicon, silicon carbide, or glassy carbon provided with about several hundred fine holes having a diameter of about 0.4 to 0.5 mm. It is introduced into the etching chamber 1.

Above the gas supply plate 4, a disk-shaped antenna 5 for radiating microwaves in the UHF band is provided.
The microwave is supplied from the power source 6 to the antenna 5 via the matching circuit 7 and the introduction shaft 8, and furthermore, the resonance electric field in the space above the antenna 5 passes through the dielectric 9 and the etching chamber 1.
Will be introduced. The frequency of the microwave is selected in a band that can lower the electron temperature of the plasma from about 0.25 eV to about 1 eV, and is in a range of 300 MHz to 1 GHz, in this case, 450 MHz.

Although the dielectric 9 is made of quartz, other than quartz, a ceramic such as alumina or aluminum nitride or a heat-resistant polymer such as polyimide having a small dielectric loss can be used. The temperature of the antenna 5 is adjusted by supplying a coolant whose temperature is adjusted by a coolant supply system and a coolant channel (not shown).

A wafer mounting electrode 1 is provided below the gas supply plate 4.
0 is provided, and the wafer 11 is supported by electrostatic attraction. Reference numeral 12 denotes a power supply for applying a DC high voltage for electrostatic attraction. In addition, a high-frequency bias is applied to the wafer mounting electrode 10 from the high-frequency power supply 13 in order to draw ions in the plasma into the wafer 11.

The wafer mounting electrode 10 has an up-and-down mechanism (not shown) for setting a wafer transfer operation and an inter-electrode distance (distance between the gas supply plate 4 and the wafer mounting electrode 10). Further, the wafer mounting electrode 10 is provided with a coolant temperature controller (not shown) for controlling the temperature and a flow path (not shown) for flowing the coolant.

The temperature of the inner wall 14 of the etching chamber is controlled to a constant temperature, in this case, 30 ° C. by introducing a temperature-controlled coolant to the inner wall 14.

A vacuum chamber 15 connected to the etching chamber 1 is provided with a turbo molecular pump 16 having a pumping speed of about 2000 to 3000 L / s. At the opening of the turbo-molecular pump 16, a pressure adjusting valve 17 for adjusting an exhaust speed is installed, and the exhaust speed is adjusted to achieve a flow rate and a pressure suitable for etching. Further, a stop valve 18 for isolating the turbo molecular pump while operating when the chamber is opened to the atmosphere, and a vacuum gauge 19 for measuring the pressure of the etching chamber 1 and controlling the pressure are provided.

Next, FIG. 2 shows details of the wafer mounting electrode portion of the plasma etching apparatus. The wafer mounting electrode 10
Electrode base 101, electrode insulating plate 102, electrode ground plate 1
03. The electrode base 101 has
A coolant circulation channel (not shown) is provided to control the temperature. A high voltage or a high frequency bias for electrostatic attraction is applied from the power supply 12 or the high frequency power supply 13.
Further, an insulating film 104 for electrostatic attraction is formed on the wafer mounting surface 101a of the electrode base 101. The insulating film 104 is also formed on the outer peripheral portion of the wafer mounting surface 101a and functions as a protective member for the electrode, and the ring 105 and the susceptor 106 are provided.

A ring 105, which is an annular member, is disposed on the susceptor 106 and the electrode base 101
Is fixed on the outer peripheral surface 101b by electrostatic attraction.
Accordingly, the ring 105 is firmly fixed at the time of processing, and the ring 105 need not be fixed at the time of assembly, thereby simplifying the device configuration. An insulating ring 107 is provided inside the susceptor 106, and an electrode cover 108 is provided so as to be sandwiched between the insulating ring 107 and the susceptor 106. In this embodiment, the end face of the electrode cover 108 is designed to enter the inside of the susceptor 106, so that the end face is not directly exposed to plasma.

The ring 105 is made of silicon, silicon nitride or glassy carbon in order to provide an effect of scavenging excess fluorine in the plasma.
Made of silicon. Various materials can be used for the susceptor 106 as long as it is an insulating material. However, in this embodiment, the susceptor 106 is consumed by being exposed to plasma, and when fluorine is contained in the plasma, aluminum fluoride is generated when alumina is used. The susceptor 106 is made of quartz in consideration of the possibility that the susceptor may become a foreign substance. The insulating ring 107 is made of an insulating material, here, alumina. The electrode cover 108 is made of an electric conductor such as an aluminum alloy.
An anodic oxide film is formed on the surface of the electrode cover to be electrically connected to the electrode ground plate 103 and prevent plasma damage. As a protective film for preventing plasma damage, it is also effective to use a polyimide coating or a thermal spraying to form an alumina oxide film in addition to the anodic oxide film.

Next, an example of plasma etching using this embodiment will be described. A silicon oxide film is formed on the surface of the wafer 11, the base is silicon nitride, and the mask is a photoresist. Ar and C as etching gases
₄ A mixed gas of F ₈ and O ₂ is used, and the gas flow rate is 5
It is 00, 10, 5 mL / min. The pressure is 2 Pa. The output of the UHF microwave power supply 6 is 1 kW, and the output of the high frequency power supply 13 for bias application to the wafer 11 is 60 kW.
0 W.

First, the wafer 11 is loaded into the etching chamber 1 evacuated to a high vacuum by a transfer arm (not shown) in a transfer chamber, and is transferred onto the wafer mounting electrode 10. The transfer arm is retracted and the etching chamber 1
After the valve between the wafer and the transfer chamber is closed, the wafer mounting electrode 1
0 rises and stops at a position suitable for etching. The stop position can set the distance (inter-electrode distance) between the wafer 11 and the gas supply plate 4 between 30 mm and 120 mm, for example, 70 mm.

Next, the coil 2 is energized to generate a resonance magnetic field 0.016T of the UHF microwave of 450 MHz between the gas supply plate 4 and the wafer mounting electrode 10. Microwave power supply 6
Is operated, electron cyclotron resonance causes EC
Strong plasma is generated in the R region.

In order to make the etching characteristics uniform, it is necessary to make the ion density incident on the wafer 11 uniform.
Since the CR position can be freely adjusted by the magnetic field coil 2, an optimum ion density distribution can be obtained. In the present embodiment, the shape of the ECR region was adjusted to be convex toward the wafer 11, and the ECR region was formed at a position 50 mm from the gas supply plate 4 (20 mm from the wafer 11).

After the plasma is generated by the UHF microwave, a high voltage is applied to the wafer mounting electrode 10 from the DC power supply 12 for electrostatic chuck, and the wafer 11 is electrostatically chucked. Helium gas is introduced to the back surface of the wafer 11 electrostatically adsorbed, and the temperature of the wafer is adjusted via the helium gas between the wafer mounting surface 101a of the wafer mounting electrode 10 and the wafer whose temperature has been adjusted by the coolant. In this case, the coolant temperature of the wafer mounting electrode 10 is set to 50 ° C.

Next, the high-frequency power supply 13 is operated to apply a high-frequency bias to the wafer mounting electrode 10. Thereby, ions are vertically incident on the wafer 11 from the plasma. In the oxide film etching, high energy ion incidence is indispensable. In this case, the high frequency bias voltage Vpp (voltage between the maximum peak and the minimum peak) is set to 1400V.

Etching is started at the same time when the bias voltage is applied to the wafer 11. After the oxide film is etched and over-etching is appropriately added, the power supply of the high-frequency power supply 13 is stopped to terminate the etching. In this case, the case where the etching is completed in a predetermined etching time or, although not shown, the change in plasma emission intensity of the reaction product is monitored to determine the etching end point, and after performing appropriate over-etching, the etching is performed. There are both cases of ending.

Next, a step of detaching the electrostatically attracted wafer 11 from the wafer mounting electrode 10 is required. As the charge removing gas, argon or a gas species actually used for etching is used. After the supply of the electrostatic chucking voltage is stopped and the power supply line is connected to the ground, a static elimination time of about 10 seconds is provided while maintaining the microwave discharge. As a result, the charges on the wafer 11 are discharged to the ground via the plasma, and the electrostatic attraction force is lost. In this state, wafer 1
1 can be detached. When the neutralization step is completed, the supply of the neutralization gas is stopped, and the microwave power supply 6 is also stopped. Further, the power supply to the coil 2 is stopped. Next, the height of the wafer mounting electrode 10 is lowered to the wafer transfer position.

After the supply of the charge removing gas is stopped, the etching chamber 1 is evacuated to a high vacuum with the pressure adjusting valve 17 fully opened. When the high vacuum evacuation is completed, the valve between the transfer chamber and the transfer chamber is opened, the transfer arm is inserted, and the wafer 11 is received and unloaded. If there is the next etching, a new wafer is loaded and the etching is performed again according to the above-described procedure.

The above is a typical flow of the etching process, and this process is repeatedly performed. As the number of processed wafers increases, a deposition film is formed inside the etching chamber 1 (such as an inner wall) and on the wafer mounting electrode 10. In addition, since ions in the plasma are incident on a location where a bias is applied, the formation of a deposited film is promoted by ion assist. Alternatively, the surface of the member may be sputtered and consumed without forming the deposition film.

In the wafer mounting electrode 10, the susceptor 10
Reference numeral 6 denotes a member which is easily damaged by plasma. Also, the electrode cover may be subject to plasma damage. However, not the entire area of the electrode cover 108 but the upper end face is most easily sputtered by the plasma. This is because the sheath tends to concentrate on the portion where the tip protrudes, and the ions also concentrate and enter. Therefore, the electrode cover 108
It is necessary to prevent the end face on which the sheath is concentrated from being exposed to plasma, and the upper end of the electrode cover 108 is made of an insulating susceptor as shown in this embodiment. The structure covered by 106 is effective as a measure against plasma. In the case of the present embodiment, the electrode cover 108
Since the end faces of the electrodes are not worn, the service life is extended, and the effect of damaging the surface of the electrode cover and becoming a foreign substance is also suppressed.

In the etching of the oxide film, excess fluorine is scavenged by a ring 105 made of silicon. Therefore, a high-frequency bias similar to that of the wafer 11 is applied to the ring 105. Therefore, ions are vertically incident on the surface of the ring 105, but at the end face of the ring 105,
Ions are also incident from the horizontal direction in FIGS. The high frequency bias acts through the insulator even if an insulator such as quartz or alumina exists between the member and the plasma. In the case of the conventional electrode, since the end face of the electrode cover that causes the scavenging action is exposed to the plasma, a high-frequency bias is also applied to the end face, and a bias circuit is easily formed via the plasma.

On the other hand, the end face of the ring 105 of this embodiment is
Covered by susceptor 106 and not directly exposed to plasma. Therefore, the impedance between the ring 105 and the inner wall 14 is large. Therefore, a bias high-frequency circuit is formed between the ring 105 and the antenna 5 (including the gas supply plate 4). As a result, the wafer 11
The same level of bias is also applied to the ring 105,
It is possible to prevent the bias from becoming non-uniform in the outer peripheral portion of the wafer. Further, the end face of the ring 105 is hardly consumed and the life is long. Also, since a weak bias is applied to the susceptor 106, no deposition film is formed,
There is also an effect that generation of foreign matter is suppressed.

FIG. 3 shows another embodiment of the present invention. In this drawing, the same reference numerals as those in FIG. 2 denote the same members, and a description thereof will be omitted. This drawing differs from FIG. 2 in that the end face of the susceptor 106a is aligned with the end face of the susceptor 105, and covers 109 are provided on both end faces of the susceptor 105 and the susceptor 106a. Another point is that the inner rear surface of the susceptor 105 is electrically connected via a bias adjustment ring 110.

Since the cover 109 is likely to be sputter-damaged by the plasma, the cover 109 is made of quartz.
09 has the following advantages. When the susceptor 106a is worn out and needs to be replaced, in the embodiment of FIG. 2, the susceptor 106a must be replaced.
The price of parts is high. Even if most of the susceptor 106a is not worn, it must be replaced.
By employing 9, only the worn part can be replaced. The cover 109 is lower in price than the susceptor 105.

The bias applied to the ring 105 is
The load is not applied directly from the electrode base 101 but is applied via the bias adjustment ring 110. If the bias adjustment ring 110 is made of a metal conductor, it becomes the same as the direct bias application shown in FIG. However, if the ring 105 is made of a dielectric material such as alumina, the applied bias to the ring 105 is reduced as compared with the direct bias application. Further, the level varies depending on the dielectric constant and thickness of the bias adjustment ring 110. That is, the amount of bias applied to the ring 105 can be adjusted.

As described above, when the bias application circuit for the ring 105 is formed between the inner wall 14 and the inner wall 14, plasma damage to the inner wall 14 is likely to occur. Therefore, the ring 10
The bias to 5 is necessary to effectively perform fluorine scavenging, but the structure must be such that the inner wall 14 and the bias circuit are difficult to form. Ring 105 of the present embodiment
The structure of the susceptors 106 and 106a is in line with the gist thereof, and it is important to suppress damage to the end face of the electrode cover 108 from the viewpoint of reducing foreign matter.

In this embodiment, the UHF-ECR plasma etching apparatus has been described as an example. However, there is no problem with other plasma sources, and the present invention is not limited to the UHF-ECR plasma etching apparatus. Therefore, the present invention can be applied to any plasma processing apparatus that applies a high-frequency bias to the wafer mounting electrode regardless of the plasma generation method.

[0041]

As described above, according to the present invention, it is possible to suppress the consumption of the susceptor of the wafer mounting electrode and the consumption of the electrode cover, thereby extending the life and suppressing the generation of foreign matter. Further, the susceptor structure in which the impedance between the ring to which the high-frequency bias is applied and the inner wall is increased has the effect of suppressing damage to the inner wall.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a plasma etching apparatus to which the present invention is applied.

FIG. 2 is a partial longitudinal sectional view showing details of a wafer mounting electrode section of the apparatus of FIG. 1;

FIG. 3 is a partial longitudinal sectional view showing another embodiment of the wafer mounting electrode section of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Etching chamber, 2 ... Coil, 3 ... Gas supply pipe, 4 ...
Gas supply plate, 5: antenna, 6: power supply, 7: matching circuit, 8: introduction axis, 9: dielectric, 10: wafer mounting electrode, 11: wafer, 12: power supply, 13: high frequency power supply, 1
4 ... inner wall, 15 ... vacuum chamber, 16 ... pump, 17 ... pressure regulating valve, 18 ... stop valve, 19 ... vacuum gauge, 10
DESCRIPTION OF SYMBOLS 1 ... Electrode base, 101a ... Wafer mounting surface, 101b ...
Outer peripheral surface, 102: electrode insulating plate, 103: electrode ground plate,
104: insulating film, 105: ring, 106, 106a ...
Susceptor, 107: insulating ring, 108: electrode cover, 10
9 ... Cover, 110 ... Bias adjustment ring.

Claims (11)

[Claims] 1. A plasma processing apparatus for processing a sample by electrostatically holding a sample on an electrode provided in a processing chamber and applying a high-frequency bias to the sample independently of generation of plasma in the processing chamber. Positioning an annular member having an annular plasma component adjusting function on the outer periphery of the sample on the dielectric film for electrostatic adsorption provided on the electrode, and electrostatically adsorbing the annular member on the electrode; A plasma processing apparatus, wherein the high-frequency resistance member is arranged so as to be capable of being held and an outer peripheral end surface of the annular member. 2. A vacuum processing chamber, a sample stage for mounting a sample to be processed in the vacuum processing chamber, gas supply means for supplying a gas for generating plasma into the vacuum processing chamber, In a plasma processing apparatus, comprising: a plasma generation unit configured to convert a gas supplied into a chamber into plasma; and a bias application unit configured to apply a high-frequency bias to the sample independently of the plasma generation unit, wherein the sample stage supports the sample. A protective member made of an insulator for protecting the sample stage from plasma damage and an annular member made of a conductor are provided on the outer peripheral surface. A high-frequency circuit is formed so that a high-frequency bias is also applied to the annular member when a high-frequency bias is applied to the sample; A plasma processing apparatus comprising a high-frequency resistance member made of an edge material. 3. The plasma processing apparatus according to claim 2, wherein the processing of the sample is a plasma etching processing.
The plasma generating gas is a gas containing carbon, oxygen, and fluorine, and the sample is a single layer or a laminated film of silicon oxide or silicon nitride or a low dielectric constant material formed on the surface of a silicon wafer. A plasma processing apparatus, wherein the member is made of quartz. 4. The plasma processing apparatus according to claim 2, wherein said annular member is made of any one of silicon, silicon carbide, and glassy carbon. 5. The plasma processing apparatus according to claim 2, wherein said annular member is mounted on a conductor or insulator member provided on an outer periphery of said sample stage. Processing equipment. 6. The plasma processing apparatus according to claim 2, wherein the processing of the sample is a plasma etching processing.
The plasma generating gas is a gas containing carbon, oxygen and fluorine, and the sample is a single layer or a laminated film of silicon oxide or silicon nitride or a low dielectric constant material formed on the surface of a silicon wafer. Plasma processing equipment. 7. The plasma processing apparatus according to claim 2, wherein a cover for preventing diffusion of plasma and reaction products generated by the plasma processing is provided below the high-frequency resistance member. apparatus. 8. The plasma processing apparatus according to claim 7, wherein an end face of the cover is provided on an inner peripheral side of the high-frequency resistance member, and direct contact between the end face of the cover and the plasma is prevented. Plasma processing equipment. 9. The plasma processing apparatus according to claim 2, wherein said sample stage is movable up and down. 10. The plasma processing apparatus according to claim 9, wherein said cover comprises a plurality of cylindrical members, said plurality of covers being arranged concentrically on one another, and at least one of said plurality of covers is provided. Is electrically connected to and fixed to the bottom surface of the vacuum processing chamber to which the sample stage is fixed, and the other cover of the plurality of covers is electrically connected to the ground potential portion of the vertically moving sample stage. A plasma processing apparatus which is connected and fixed. 11. The plasma processing apparatus according to claim 7, wherein the cover is made of an aluminum alloy,
A plasma processing apparatus comprising an anodic oxide film, an alumina coating film, or a heat-resistant polymer material coating film formed on the surface.