JP4871028B2 - Plasma processing equipment - Google Patents

Description

  The present invention relates to an apparatus for plasma processing a processing object by converting a processing gas into plasma in a discharge space, blowing it out, and hitting the processing gas disposed on the outside of the discharge space.

For example, the plasma processing apparatus described in Patent Document 1 includes a pair of electrodes held by an insulating holder, and a pair of dielectric plates respectively provided on opposing surfaces of these electrodes. A voltage is applied between the pair of electrodes to form a discharge, and a processing gas is introduced into a passage between the pair of dielectric plates to form plasma. The plasma-treated processing gas is blown downward and applied to the object to be processed to perform surface treatment of the object to be processed. The electrode is connected to the upper side of the holder and one side by a bolt and supported. A narrow gap is formed between the side end surface and the lower end surface of the electrode opposite to the bolt connection side and the holder to absorb the difference in thermal expansion between each other.
Patent Document 2 describes that a plurality of L-shaped pieces are arranged apart from each other in the longitudinal direction of the electrodes, and these L-shaped pieces are applied to the back and bottom surfaces of the electrodes to support the electrodes. . An insulating space is formed at the back and bottom of the electrode between adjacent L-shaped pieces.
JP 09-92493 A JP 2006-49262 A (paragraph 0038)

In this type of plasma processing apparatus, abnormal discharge such as creeping discharge is likely to occur between the electrode and a holder made of an insulator that holds the electrode. Such an abnormal discharge not only causes damage and deterioration of device components such as holders and electrodes, but also tends to cause particles.
The narrow gaps between the side and lower end surfaces of the electrode and the holder in Patent Document 1 can absorb the difference in thermal expansion, but are insufficient to prevent abnormal discharge such as creeping discharge. In particular, the abnormal discharge tends to run from the side end surface of the electrode toward the side end surface of the other electrode.
If the insulating member on the back portion of the electrode is omitted and an insulating space is provided between the electrode back portion and the metal side wall as in Patent Document 2, creeping discharge on the electrode back portion can be prevented. There is no description on preventing abnormal discharge. Further, since the L-shaped piece is applied to the back surface of the electrode to support the electrode, abnormal discharge may occur on this contact surface.

In order to solve the above problems, the present invention performs plasma processing by passing a processing gas in a first direction of a discharge space to an object to be disposed outside the discharge space on the downstream side in the first direction. In the device
(A) a first electrode and a second electrode facing the second direction intersecting the first direction and forming the discharge space therebetween;
(B) a metal case surrounding the first electrode and the second electrode as viewed from the first direction;
(C) a dielectric member made of a solid dielectric provided on a surface of the first electrode facing the second electrode;
With
Both end portions of the dielectric member intersecting the first direction and the second direction and not existing in a plane defined by the first direction and the second direction extend from the first electrode, Constituting a pair of third direction extending portions,
And the facing surface opposite the back surface and the end surface and other end surface of one of the third direction of the first electrode, and the housing, by said pair of third direction extending portion, the first A side insulating space that insulates one electrode from the housing is defined , and the side insulating space is defined between the back surface, the wall surface facing in the second direction, and the back surface of the housing. A space portion on the back side, a space portion on one end side defined between the one end surface of the housing, the wall surface facing the first direction, and the one end surface, and the other end surface of the housing. And a space portion on the other end side defined between the wall surface facing the first direction and the other end surface,
One end portion in the second direction of the space portion on the one end side is defined by one of the third direction extending portions, and the other end portion in the second direction of the space portion on the one end side is the back portion. The one end in the third direction of the space portion on the side,
One end portion in the second direction of the space portion on the other end side is defined by the other third direction extending portion, and the other end portion in the second direction of the space portion on the other end side is defined as It is connected to the other end portion in the third direction of the space portion on the back side .
Thereby, it is not necessary to arrange a member for insulating the first electrode between the back portion of the first electrode and both ends in the third direction and the housing, and creeping discharge is generated between the insulating member and the first electrode. It can be prevented from occurring. In addition, abnormal discharge can be prevented from flying from the end of the first electrode in the third direction toward the second electrode by the third direction extension of the dielectric member. Thereby, damage to the first and second electrodes can be prevented, maintenance frequency can be reduced, and generation of particles can be prevented.

It is preferable that an upstream insulating member made of an insulating material is provided between the upstream end of the first electrode in the first direction and the housing.
It is preferable that the first electrode is connected to the upstream insulating member so as to hang substantially the entire weight.
Accordingly, only the upstream end portion of the first electrode can be connected to and supported by the casing via the upstream insulating member. Between the back of the first electrode and both ends in the third direction and the housing, it is not necessary to arrange a member that insulates and supports the first electrode, a side insulating space can be formed reliably, and abnormal discharge occurs. As a result, generation | occurrence | production of a particle can be prevented reliably.

It is preferable that the dielectric member has an upstream extending portion that extends to the upstream side in the first direction from the first electrode.
Thus, it is possible to prevent abnormal discharge from flying from the upstream end of the first electrode to the second electrode.
It is preferable that the upstream extending portion is connected to the upstream insulating member such that substantially the entire weight of the dielectric member is applied to the upstream insulating member.
Accordingly, only the upstream extension portion of the dielectric member can be connected to and supported by the housing via the upstream insulating member.
It is preferable to use an adhesive as a joining means between the upstream insulating member and the dielectric member.

It is preferable that a downstream conductive member made of metal is provided at the downstream end of the housing in the first direction. This downstream conductive member is preferably electrically grounded.
This prevents abnormal discharge from flying from the first electrode to the object to be processed, avoids damage to the object to be processed, and allows the first electrode and thus the discharge space to approach the object to be processed. It is possible to reliably reach the object to be processed before the generated active species are deactivated. As a result, the processing rate can be improved.
It is preferable that the dielectric member has a downstream extending portion that extends downstream from the first electrode in the first direction.
The first electrode is insulated from the downstream member by the downstream end portion of the first electrode in the first direction, the downstream conductive member, and the downstream extension portion, and the side insulation. It is preferable that a downstream insulating space connected to the space is defined.
This eliminates the need to dispose a member that insulates the first electrode between the first electrode and the downstream conductive member, and prevents creeping discharge from occurring between the insulating member and the downstream side surface of the first electrode. Can be prevented. Furthermore, abnormal discharge can be prevented from flying from the downstream end of the first electrode to the second electrode by the downstream extension of the dielectric member. This can more reliably prevent damage to the first and second electrodes and the generation of particles.

It is preferable that the downstream conductive member is formed with a blowout port that is continuous with the discharge space.
It is preferable that the end of the downstream extending portion of the dielectric member is disposed so as not to protrude from the downstream member in the vicinity of the outlet.
Accordingly, the downstream conductive member can protect the dielectric member from being damaged.

The present invention is suitable for generating plasma and performing surface treatment near atmospheric pressure. The vicinity of atmospheric pressure (substantially normal pressure) refers to a range of 1.013 × 10 ^{4 to} 50.663 × 10 ⁴ Pa, and considering the ease of pressure adjustment and the simplification of the apparatus configuration, 1.333 × 10 6. ^{4 to} 10.664 × 10 ⁴ Pa (100 to 800 Torr) is preferable, and 9.331 × 10 ^{4 to} 10.9797 × 10 ⁴ Pa (700 to 780 Torr) is more preferable.

  According to the present invention, creeping discharge at the back portion of the first electrode and both ends in the third direction can be prevented, and abnormal discharge can be prevented from flying from the end portion in the third direction toward the second electrode. it can. Thereby, damage to the first and second electrodes can be prevented, maintenance frequency can be reduced, and generation of particles can be prevented.

Hereinafter, a first embodiment of the present invention will be described.
1 to 3 show an atmospheric pressure plasma processing apparatus. The apparatus includes a processing head 1. The processing head 1 is supported by a gantry (not shown). As shown in FIG. 2, an object to be processed W such as a liquid crystal glass substrate or a semiconductor substrate is disposed at a processing position below the processing head 1. The workpiece W is moved, for example, forward (in the direction of the arrow in FIG. 2) by a transport mechanism (not shown). The processing head 1 may be moved while the workpiece W is stationary.

  The processing head 1 includes an upper rectification unit 2 and a lower plasma generation unit 3. The rectifying unit 2 extends in the left-right direction (direction orthogonal to the paper surface of FIG. 2). The rectification unit 2 is connected to the processing gas source G. In the processing gas source G, processing gas corresponding to the processing purpose is stored. The rectifying unit 2 is configured to uniformize the processing gas supplied from the processing gas source G in the longitudinal direction (left and right).

The plasma generation unit 3 of the processing head 1 includes a housing 10 and a pair of first electrode 31 and second electrode 32.
The housing 10 is made of a metal such as stainless steel and is electrically grounded. As shown in FIG. 1, the housing 10 includes a pair of long walls 11 and 12 on the front and rear sides and a pair of short walls 13 and 13 on the left and right sides, and is long in the left and right (third direction) in plan view. It has a rectangular shape.

  As shown in FIGS. 2 and 3, a bottom member 14 (downstream conductive member) made of a metal such as stainless steel is provided at the lower end portion of the housing 10. The bottom member 14 has a rectangular plate shape whose longitudinal direction is directed to the left and right, and closes the bottom of the housing 10. A low peripheral wall 14 a is integrally provided on the peripheral edge of the bottom member 14. The front and rear portions of the peripheral wall 14 a are abutted against the lower surfaces of the long walls 11 and 12. The left and right short walls 13, 13 are in contact with the left and right outer surfaces of the peripheral wall 14 a and are connected by bolts 15.

  The bottom member 14 is electrically grounded to the walls 11, 12, 13, and 13 of the housing 10 through a common or separate ground wire. The bottom member 14 prevents abnormal discharge such as arcing from the electrode 31 to the workpiece W. Thereby, while avoiding damage to the workpiece W, the electrode 31 and thus the discharge space 23 described later can be brought close to the workpiece W, and the active species generated in the discharge space 23 are not deactivated. It is possible to reliably reach W and improve the processing rate.

  As shown in FIG. 2, an outlet 24 is formed at the center of the bottom member 14. The outlet 24 has a slit shape and extends left and right.

  A pair of a first electrode 31 and a second electrode 32 are housed inside the housing 10. Each electrode 31 and 32 is comprised with metals, such as stainless steel. The electrodes 31 and 32 have a substantially rectangular cross section as shown in FIG. 2, and extend left and right (in the third direction) as shown in FIG. The lengths of the electrodes 31 and 32 are preferably larger than the dimension in the front-rear direction of the workpiece W to be processed.

  The first electrode 31 faces the one long wall 11 of the housing 10 in parallel, and the second electrode 32 faces the other long wall 12 in parallel. The left and right short walls 13, 13 are opposed to the left and right end faces (end faces in the third direction) of the electrodes 31, 32, respectively. The four walls 11, 12, 13, 13 surround the first and second electrodes 31, 32 in plan view (viewed from the first direction).

  The pair of electrodes 31 and 32 are arranged in parallel so as to face each other in the front-rear direction (second direction). Among these electrodes 31 and 32, a power supply terminal 36 is provided at the center in the longitudinal direction of one first electrode 31. The power supply terminal 36 passes through the long wall 11 facing the first electrode 31 of the housing 10 and is connected to the power source P. Thereby, the 1st electrode 31 is a power supply electrode (voltage application electrode).

  A ground terminal 37 is provided at the center in the longitudinal direction of the other second electrode 32 of the electrodes 31 and 32. The ground terminal 37 passes through the long wall 12 facing the second electrode 32 of the housing 10 and is connected to the ground line 38. As a result, the second electrode 32 is a ground electrode.

By supplying a voltage to the power supply electrode 31, an electric field is applied between the pair of electrodes 31 and 32 to generate an atmospheric pressure plasma discharge.
The applied voltage is preferably about Vpp = 10 to 30 kV, for example, and the frequency is preferably about 1 to 200 kHz, for example.

  As shown in FIGS. 2 and 3, a cooling path (temperature control path) 39 is formed inside each of the electrodes 31 and 32. The cooling path 39 extends in the longitudinal direction (left-right direction) of the electrodes 31 and 32. Both end portions of the cooling path 39 are bent to the back portion (opposite to the facing surface) slightly before the left and right end surfaces (end surfaces in the third direction) of the electrodes 31 and 32 and are opened on the back surface. Although illustration is omitted, a refrigerant supply path is connected to one of the openings at both ends of the cooling path 39, and a discharge path is connected to the other. Thus, the refrigerant is passed through the cooling passage 39, and the electrodes 31 and 32 are cooled (temperature controlled). For example, water is used as the refrigerant (temperature control medium).

A dielectric member 51 is provided on the surface of the first electrode 31 facing the second electrode 32. Similarly, a dielectric member 52 is provided on the surface of the second electrode 32 facing the first electrode 31. These dielectric members 51 and 52 are formed of a solid dielectric such as ceramics including alumina (Al ₂ O ₃ ), the longitudinal direction is directed to the left and right, and the lateral direction is directed to the top and bottom (first direction). It has a thin rectangular plate shape. As shown in FIG. 3, the dielectric members 51 and 52 have a larger area than the electrodes 31 and 32, and four peripheral portions on the top, bottom, left, and right extend beyond the electrodes 31 and 32. That is, the left and right ends of the dielectric members 51 and 52 constitute a third direction extending portion 53 that extends left and right (third direction) from the electrodes 31 and 32, and the upper ends of the dielectric members 51 and 52 are electrodes. The upstream side extension part 54 that extends upward from the electrodes 31 and 32 is configured, and the lower end part forms the downstream side extension part 55 that extends downward from the electrodes 31 and 32.

  As shown in FIG. 2, the lower end portions of the dielectric members 51 and 52 (end portions of the downstream-side extending portions 55) are located at substantially the same height as the upper surface of the bottom member 14 and face the blowout port 24. The lower end portions of the dielectric members 51, 52 may be slightly above the upper surface of the bottom member 14, and may be inserted into the outlet 24, but do not protrude below the outlet 24. Is preferred. Thus, when the processing head 1 is placed on the floor or the like, the dielectric members 51 and 52 can be protected without applying an excessive force to the lower ends of the dielectric members 51 and 52.

  As shown in FIGS. 1 and 2, a slit-like inter-dielectric member gas path 22 is formed between the pair of dielectric members 51 and 52. As shown in FIGS. 1 and 3, spacers 56 made of a dielectric material are sandwiched between the left and right sides between the pair of dielectric members 51 and 52. The spacer 56 ensures the thickness of the gas path 22 between the dielectric members. The spacer 56 and the dielectric members 51 and 52 are bonded to each other with an adhesive.

The portion corresponding to the height of the central electrodes 31 and 32 in the vertical direction of the gas path 22 between the dielectric members becomes a discharge space 23 by applying a voltage to the electrodes 31.
The lower end portion of the gas path 22 between the dielectric members is directly connected to the outlet 24.

The electrodes 31 and 32 and the dielectric members 51 and 52 are supported by the housing 10 as follows.
As shown in FIGS. 2 and 3, an upstream insulating member 60 is provided inside the housing 10. The upstream insulating member 60 is made of an insulator having high plasma resistance such as Unirate (registered trademark) and extends in the left-right direction. The upstream insulating member 60 is connected to the housing 10 with a bolt 61.

  The upper surfaces of the electrodes 31 and 32 are assigned to the lower surface of the upstream insulating member 60. The upstream insulating member 60 insulates the upper ends of the electrodes 31 and 32 from the housing 10. A bolt 62 is passed through the upstream insulating member 60, and the tip of the bolt 62 is screwed into the electrodes 31 and 32. As a result, the electrodes 31 and 32 are suspended from the upstream insulating member 60, almost the entire load is applied to the upstream insulating member 60, and supported by the housing 10 via the upstream insulating member 60. ing.

  As shown in FIGS. 2 and 3, a slit 60 a is formed in the central portion of the upstream insulating member 60. The slit 60a penetrates the upstream insulating member 60 up and down and extends left and right. As shown in FIG. 2, the upper ends of the pair of dielectric members 51 and 52 are inserted in the lower part of the slit 60a. The dielectric member 51 on the first electrode 31 side is bonded to one inner wall of the slit 60a with an adhesive, and the dielectric member 52 on the second electrode 32 side is bonded to the other inner wall of the slit 60a with an adhesive. Has been. As a result, the dielectric members 51 and 52 are suspended from the upstream insulating member 60, and the entire load is applied to the upstream insulating member 60 and supported by the casing 10 via the upstream insulating member 60. Has been.

  Lower portions of the inner walls on both sides of the slit 60a of the upstream insulating member 60 form sloped relief portions 60b and 60c that incline outwardly toward the lower surface of the upstream insulating member 60, respectively. A space having a triangular cross section is formed by one relief portion 60b, the upper surface of the electrode 31, and the upper end portion of the dielectric member 51. The escape portion 60 b prevents the upstream insulating member 60 from coming into contact with the corner formed by the upper surface of the electrode 31 and the upper end portion of the dielectric member 51. As a result, the occurrence of creeping discharge between the upstream insulating member 60 and the electrode 31 is prevented. Similarly, a space having a triangular section is formed by the other relief portion 60 c, the upper surface of the electrode 32, and the upper end portion of the dielectric member 52, and the upstream insulating member 60 is formed by the upper surface of the electrode 32 and the upper end portion of the dielectric member 52. It is designed not to touch the corner.

  The first electrode 31 and the dielectric member 51 are in contact with each other while being suspended from the upstream insulating member 60. Similarly, the second electrode 32 and the dielectric member 52 are in contact with each other while being suspended from the upstream insulating member 60.

  Bolts (pressing members) may be screwed horizontally into the long walls 11 and 12 of the housing 10 and the electrodes 31 and 32 may be pressed against the dielectric members 51 and 52 with these bolts. If it does so, the adhesive agent between the dielectric members 51 and 52 and the upstream insulating member 60 becomes unnecessary. The adhesive between the dielectric members 51 and 52 and the spacer 56 is also unnecessary. The bolt (pressing member) that presses the electrode 31 on the power supply side is preferably made of an insulating material such as resin or ceramic. It is preferable to use a metal bolt (pushing member) that presses the ground-side electrode 32, and it is more preferable to use this metal bolt as the ground electrode 32 or the ground terminal of the housing 10.

The upper portion of the slit 60 a of the upstream insulating member 60 constitutes a gas introduction hole 21 that continues to the rectifying unit 2. A gas path 22 between the dielectric members 51 and 52 is connected to the gas introduction hole 21.
The processing gas that has been made uniform in the left-right direction by the rectifying unit 2 is guided to the inter-dielectric member gas path 22 through the gas introduction hole 21, and the upper end portion (upstream end in the first direction) in the inter-dielectric member gas path 22 ) From below, and passing through the discharge space 23 on the way, it is turned into plasma (excited and activated). The plasma-treated processing gas is blown downward from the blowing port 24 through the dielectric member gas path 22 below the discharge space 23 (downstream in the first direction) and comes into contact with the surface of the workpiece W. And cause a reaction. Thereby, desired surface treatments such as cleaning, surface modification, etching, ashing, and film formation can be performed.

In the housing 10, only the upstream insulating member 60 is disposed as an insulating member for the electrodes 31 and 32, and the back portions (opposite surfaces opposite to each other), the left and right side portions, and the lower portion of the electrodes 31 and 32. There is no insulating member disposed on the surface.
As shown in FIG. 1, the first electrode 31 and the long wall 11 of the housing 10 are separated from each other by a distance that causes dielectric breakdown when voltage is applied to the first electrode 31 (hereinafter referred to as “dielectric breakdown distance”). Yes. Furthermore, the left and right ends of the electrode 31 and the left and right short walls 13 and 13 of the housing 10 are separated from each other by a distance greater than the dielectric breakdown distance. As a result, the side insulating space 71 is defined by the back portion and the left and right end portions of the electrode 31, the portion on the first electrode 31 side of the discharge space 23 of the housing 10, and the left and right extending portions 53 of the dielectric member 51. It is made. The left and right extending portions 53 of the dielectric member 51 define an end portion of the side insulating space 71 on the second electrode 32 side. The side insulating space 71 has a U-shape in plan view and covers the back portion and both left and right end portions of the electrode 31.

  The thickness of the side insulating space 71, that is, the separation distance between the back portion of the electrode 31 and the long wall 11, and the separation distance between the left and right end portions of the electrode 31 and the short wall 13 are, for example, about 10 to 20 mm. It is preferable that The reason why the thickness is about 10 mm or more is that if it is smaller than this, the insulation between the electrode 31 and the walls 11 and 13 may not be sufficiently maintained. The reason why it is set to about 20 mm or less is that if it is larger than this, the size of the processing head 1 becomes too large. If there is no problem in size, it may exceed 20 mm.

  As shown in FIGS. 2 and 3, the lower end portion of the first electrode 31 and the bottom member 14 are separated by a distance greater than the dielectric breakdown distance. Thereby, the lower end portion of the electrode 31, the lower portion of the long wall 11 and the left and right short walls 13, 13 of the housing 10, the bottom member 14, and the downstream side extended portion 55 of the dielectric member 51, the downstream side. An insulating space 72 is defined. The end portion on the long wall 11 side and the left and right end portions of the downstream insulating space 72 are integrally connected to the side insulating space 71. The downstream extension 55 of the dielectric member 51 defines the end of the downstream insulating space 72 on the second electrode 32 side.

  The thickness of the downstream insulating space 72, that is, the separation distance between the lower end portion of the electrode 31 and the bottom member 14, is preferably about 10 to 20 mm, for example. The reason why it is about 10 mm or more is that if it is smaller than this, the insulation between the electrode 31 and the bottom member 14 may not be sufficiently maintained. If it is about 20 mm or less, if it is larger than this, the distance from the discharge space 23 to the workpiece W will be too far, and it will be difficult to maintain the activity until the processing gas reaches the workpiece W, and the processing capacity will be reduced. It is because there is a possibility of doing.

  A space similar to the insulating spaces 71 and 72 around the first electrode 31 is formed between the second electrode 32 and the walls 12 and 13 and the bottom member 14 of the housing 10. The thickness of the space around the two electrodes 32 may be narrower than that of the first electrode 31, or such a space may be eliminated and the second electrode 32 and the walls 12, 13 may be brought into contact with each other, or an insulating member between them. May be sandwiched. The bottom member 14 may not be disposed below the second electrode 32.

According to the above configuration, the side insulating space 71 can insulate the first electrode 31 and the walls 11 and 13 of the housing 10 and prevent abnormal discharge such as creeping discharge along the back surface and the left and right end surfaces of the electrode 31. Can do. Further, the downstream insulating space 72 can insulate the first electrode 31 and the bottom member 14 and can prevent abnormal discharge such as creeping discharge along the lower end surface of the electrode 31.
The left and right extending portions 53 of the dielectric member 51 can prevent abnormal discharge such as creeping discharge or arc from being formed from the left and right end surfaces of the first electrode 31 to the second electrode 32 side. The upstream extending portion 54 can prevent abnormal discharge such as creeping discharge or arc from being formed from the upper and lower end surfaces of the first electrode 31 to the second electrode 32 side. Furthermore, the downstream extension 55 of the dielectric member 51 can prevent abnormal discharge such as creeping discharge or arc from being formed from the lower end surface of the first electrode 31 to the second electrode 32 side.
Thereby, deterioration and damage of the electrodes 31 and 32 can be prevented, and generation of particles can be suppressed. Further, since the insulating member 60 is disposed only above the electrodes 31 and 32 and no insulating member is disposed on the back, bottom, and left and right sides of the electrodes 31, 32, the insulating members on the back, bottom, and left and right sides. The problem of deterioration cannot occur, and the maintenance frequency can be reduced.

The present invention is not limited to the above embodiment, and various modifications can be made.
For example, instead of the upstream insulating member 60 and the bolts 61 and 62, an insulating bolt may be hung from the upper part of the housing 10, and the electrodes 31 and 32 may be suspended and supported by the insulating bolt.
The present invention is applicable to various plasma surface treatments such as cleaning, surface modification, etching, ashing, and film formation.

  The present invention can be used for plasma surface treatment of glass substrates for flat panels such as liquid crystal panels and silicon substrates in semiconductor manufacturing.

It is a plane sectional view which meets an II line of Drawing 2 of a processing head of an atmospheric pressure plasma processing apparatus concerning one embodiment of the present invention. It is side surface sectional drawing which follows the II-II line | wire of FIG. 1 of the said processing head. It is front sectional drawing which follows the III-III line | wire of FIG. 1 of the said processing head.

Explanation of symbols

W object G processing gas source P power source 1 processing head 2 rectifying unit 3 plasma generating unit 10 housing 14 bottom member (downstream conductive member)
23 discharge space 31 first electrode 32 second electrode 51 dielectric member 53 third direction extending portion 55 downstream extending portion 60 upstream insulating member 71 side insulating space 72 downstream insulating space

Claims (5)

In an apparatus for performing a plasma treatment by passing a processing gas in a first direction of a discharge space and hitting an object to be processed disposed downstream of the discharge space in the first direction,
(A) a first electrode and a second electrode facing the second direction intersecting the first direction and forming the discharge space therebetween;
(B) a metal case surrounding the first electrode and the second electrode as viewed from the first direction;
(C) a dielectric member made of a solid dielectric provided on a surface of the first electrode facing the second electrode;
With
Both end portions of the dielectric member intersecting the first direction and the second direction and not existing in a plane defined by the first direction and the second direction extend from the first electrode, Constituting a pair of third direction extending portions,
And the facing surface opposite the back surface and the end surface and other end surface of one of the third direction of the first electrode, and the housing, by said pair of third direction extending portion, the first A side insulating space that insulates one electrode from the housing is defined , and the side insulating space is defined between the back surface, the wall surface facing in the second direction, and the back surface of the housing. A space portion on the back side, a space portion on one end side defined between the one end surface of the housing, the wall surface facing the first direction, and the one end surface, and the other end surface of the housing. And a space portion on the other end side defined between the wall surface facing the first direction and the other end surface,
One end portion in the second direction of the space portion on the one end side is defined by one of the third direction extending portions, and the other end portion in the second direction of the space portion on the one end side is the back portion. The one end in the third direction of the space portion on the side,
One end portion in the second direction of the space portion on the other end side is defined by the other third direction extending portion, and the other end portion in the second direction of the space portion on the other end side is defined as The plasma processing apparatus, which is connected to the other end portion in the third direction of the space portion on the back side . An upstream insulating member made of an insulating material is provided between the upstream end of the first electrode in the first direction and the housing.
The plasma processing apparatus according to claim 1, wherein the first electrode is connected to the upstream insulating member so as to hang substantially the entire weight of the upstream insulating member. The dielectric member has an upstream extension extending from the first electrode to the upstream side in the first direction;
3. The plasma processing according to claim 2, wherein the upstream extending portion is connected to the upstream insulating member such that substantially the entire weight of the dielectric member is applied to the upstream insulating member. apparatus. A metal downstream conductive member is provided at the downstream end of the housing in the first direction,
The dielectric member has a downstream extension extending from the first electrode to the downstream side in the first direction;
The first electrode is insulated from the downstream member by the downstream end portion of the first electrode in the first direction, the downstream conductive member, and the downstream extension portion, and the side insulation. The plasma processing apparatus according to claim 1, wherein a downstream insulating space connected to the space is defined. The downstream conductive member is formed with a blowout port that continues to the discharge space,
5. The plasma processing apparatus according to claim 4, wherein an end portion of the downstream side extension portion of the dielectric member is disposed so as not to protrude from the downstream side member in the vicinity of the blowout port.

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