JP2010073910A - Plasma processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an abnormal discharge to an inner surface of a skirt hole at the earth electrode of a plasma processing device to prevent an uneven processing. <P>SOLUTION: A dielectric member 60 is arranged on a discharge surface 42 facing an electric field applied electrode 30 of the earth electrode 40 of the plasma processing device. A plurality of skirt introduction holes 61 are formed to the dielectric member 60. A skirt hole 41 having an opening area larger than the total opening area of the plurality of skirt introduction holes 61 is formed to the earth electrode 40. The plurality of skirt introduction holes 61 are commonly connected to the skirt hole 41. Preferably, the skirt hole 41 is formed in a long-hole-shaped extending to the arrangement direction of the skirt introduction holes 61. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a plasma processing apparatus.

For example, Patent Document 1 describes a plasma processing apparatus in which a pair of electrodes are arranged to face each other in the vertical direction. The upper electrode is connected to a power source and serves as an electric field application electrode. The lower electrode is electrically grounded and serves as a ground electrode. An electric field is applied between these electrodes to generate an atmospheric pressure glow discharge, and a processing gas is introduced into plasma. The lower ground electrode is formed with a slit-like jet port. The processing gas is blown downward from the jet port. An object to be processed is disposed below the ground electrode. A processing gas from the jet port is blown onto the object to be processed so that the surface treatment is performed.
A solid dielectric layer made of a sprayed alumina film is formed on the upper surface of the ground electrode (the surface facing the electric field application electrode).
JP 2004006211 A

  In the plasma processing apparatus having the above-described structure, if the inner surface of the jet port of the ground electrode made of metal is exposed, there is a possibility that an arc may fall on the inner surface. In particular, the electric field was concentrated on the edge of the jet nozzle on the electrode application electrode side, and a discharge having a higher light emission intensity occurred at the edge, or an arc fell on the edge. In this case, there is a problem that metal contamination and particles are generated and adhere to the object to be processed.

In order to solve the above-mentioned problems, the inventor performs plasma surface treatment by converting the processing gas into plasma in the discharge space and ejecting the gas, and bringing the processing gas into contact with the object disposed in the object disposition portion outside the discharge space. In the device
An electric field applying electrode connected to a power source;
A grounding electrode having a discharge surface facing the electric field applying electrode and a processing surface facing the workpiece placement portion, and being electrically grounded;
A dielectric member made of a solid dielectric that is in contact with the discharge surface of the ground electrode and faces the electric field application electrode to define the discharge space;
The dielectric member is formed with an ejection guide hole continuous to the discharge space,
The ground electrode is formed with a jet port that is continuous with the jet guide hole and penetrates from the discharge surface to the treatment surface.
The inner surface of the ejection guide hole in the dielectric member protrudes radially inward of the ejection port from the edge on the discharge surface side of the inner surface of the ejection port in the ground electrode,
The dielectric member forms a step between the contact surface that contacts the discharge surface of the ground electrode and the inner surface of the ejection guide hole and the inner surface of the ejection port that are extended flush with the contact surface. A plasma processing apparatus having a step surface has been proposed (International Application No. PCT / JP2008 / 055278).
As a result, it is possible to prevent abnormal discharges such as arcs from falling on the inner surface of the jet nozzle in the ground electrode, and to prevent the generation of metal contamination and particles, and prevent these metal contamination and particles from adhering to the workpiece. it can.
As a specific structure, for example, it has been proposed to make the inner diameter of the ejection guide hole smaller than the inner diameter of the ejection port ((inner diameter of ejection ejection hole) <(inner diameter of ejection port)).

  It is preferable to form a plurality of ejection guide holes in the dielectric member. The ejection guide hole and the ejection port may correspond one-to-one. However, if the pitch of the ejection guide holes is too large, processing loss tends to occur. Therefore, it is preferable to make the pitch of the ejection guide holes as small as possible from the viewpoint of prevention of processing loss. On the other hand, assuming that (inner diameter of the ejection guide hole) <(inner diameter of the ejection port), if the pitch of the ejection guide holes is less than or equal to the pitch of the ejection port, adjacent ejection ports interfere with each other.

The present invention has been made on the basis of such considerations, and the processing gas is made into plasma in the discharge space and ejected, and is brought into contact with the object to be processed disposed in the object disposition portion outside the discharge space. In an apparatus for performing surface treatment,
An electric field applying electrode connected to a power source;
A grounding electrode having a discharge surface facing the electric field applying electrode and a processing surface facing the workpiece placement portion, and being electrically grounded;
A dielectric member made of a solid dielectric having an abutting surface applied to the discharge surface of the ground electrode and an defining surface that faces the electric field applying electrode and defines the discharge space;
The dielectric member is formed with a plurality of ejection guide holes penetrating from the defining surface to the contact surface, and the ground electrode is formed with an ejection port penetrating from the discharge surface to the processing surface. The opening area of the ejection port to the discharge surface is larger than the total opening area of the plurality of ejection guide holes to the contact surface, and the plurality of ejection guide holes are all connected to one ejection port. It is the characteristic which claims this.
As a result, the peripheral portion of the ejection guide hole of the dielectric member protrudes inside the opening to the discharge surface of the discharge port of the ground electrode, and an arc is formed at the edge of the opening of the discharge port, particularly to the discharge surface. It is possible to prevent the abnormal discharge such as falling and prevent the generation of particles. In addition, the arrangement interval of the ejection guide holes can be narrowed, and processing unevenness can be prevented.

It is preferable that the plurality of ejection guide holes are arranged in a row, and the ejection port has an elongated hole shape extending in the direction in which the plurality of ejection guide holes are arranged.
Thereby, a plurality of ejection guide holes can be surely connected to one ejection port.

It is preferable that the pitch of the ejection guide holes is equal to or less than the dimension in the width direction orthogonal to the extending direction of the opening of the ejection port to the discharge surface.
Thereby, the arrangement | positioning space | interval of an ejection guide hole can be narrowed sufficiently, and a process nonuniformity can be prevented more reliably.

It is preferable that the dimension in the width direction orthogonal to the extending direction of the opening to the discharge surface of the ejection port is larger than the dimension in the same direction as the width direction of the opening to the contact surface of the ejection guide hole.
Thereby, the peripheral part of the ejection guide hole of the dielectric member can be surely positioned inside the opening to the discharge surface of the ejection port, and an arc or the like is formed on the inner edge of the ejection port, particularly at the edge of the opening to the discharge surface. It is possible to reliably prevent the abnormal discharge from falling.

The difference between the dimension in the width direction orthogonal to the extending direction of the opening to the discharge surface of the ejection port and the dimension in the same direction as the width direction of the opening to the contact surface of the ejection guide hole is preferably It is 0.1-5 mm, More preferably, it is about 2 mm.
As a result, the width of the spout can be made moderately large, the area of the ground electrode can be secured, and the discharge between the ground electrode and the electric field applying electrode can be secured, and the inside of the opening to the discharge surface of the spout can be secured. In addition, it is possible to reliably prevent an abnormal discharge such as an arc from falling on the edge of the inner surface of the ejection port, particularly the opening to the discharge surface, by reliably projecting the peripheral portion of the ejection guide hole of the dielectric member.

It is preferable that the center of each ejection guide hole is disposed at the center in the width direction orthogonal to the extending direction of the ejection port.
As a result, the peripheral portion of the ejection guide hole of the dielectric member can be surely positioned inside the opening to the discharge surface of the ejection port, and an arc or the like can be formed on the inner surface of the ejection port, particularly at the edge of the opening to the discharge surface. The abnormal discharge can be prevented more reliably.

The vicinity of atmospheric pressure refers to a range of 1.013 × 10 ^{4 to} 50.663 × 10 ⁴ Pa, and 1.333 × 10 ^{4 to} 10.664 considering the ease of pressure adjustment and the simplification of the apparatus configuration. × 10 ⁴ Pa is preferable, and 9.331 × 10 ^{4 to} 10.9797 × 10 ⁴ Pa is more preferable.

  According to the present invention, it is possible to prevent an abnormal discharge such as an arc from falling on the inner surface of the ejection port of the ground electrode, particularly at the edge of the opening to the discharge surface, and to prevent the generation of particles. In addition, the arrangement interval of the ejection guide holes can be narrowed, and processing unevenness can be prevented.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 5 and 6 (a) show a first embodiment of the present invention. The atmospheric pressure plasma processing apparatus includes a processing head 1 and a workpiece placement unit 2. The processing object placement unit 2 includes a stage and a conveyor, and the processing object 9 is arranged on the upper side thereof. The workpiece 9 is, for example, a glass substrate or a semiconductor substrate.

  The workpiece placement unit 2 can transport the workpiece 9 in the direction perpendicular to the plane of FIG. The position of the workpiece 9 may be fixed, and the processing head 1 may be moved in the direction perpendicular to the plane of FIG.

  The processing head 1 is supported by a gantry (not shown) and is located above the workpiece placement unit 2. The processing head 1 includes an upper lid member 10, a frame 20, an electric field application electrode 30, and a ground electrode 40, and extends in one direction (the left-right direction in FIG. 1 and the direction perpendicular to the plane of FIG. 2).

  The upper lid member 10 is made of a highly corrosion-resistant resin (insulator) and extends in the longitudinal direction of the processing head 1.

  As shown in FIG. 4, the frame 20 has a pair of long side frame portions 21 and a pair of short side frame portions 22, and has a rectangular shape in plan view with an inside opened. The long side frame portion 21 constitutes the long side of the processing head 1. The short side frame portion 22 constitutes the short side of the processing head 1. The periphery of the upper lid member 10 is placed on the upper surface of the frame 20. The upper lid member 10 is connected to the frame 20 with bolts (not shown). The upper lid member 10 closes the internal space of the frame 20 from above.

As shown in FIG. 2, a gas introduction path 20 a is formed in each of the pair of long side frame portions 21. The gas introduction path 20 a extends in the longitudinal direction of the processing head 1. A gas supply path 4a from the processing gas source 4 is connected to one end of the gas introduction path 20a. A gas introduction port 20b is branched from a side portion of the gas introduction path 20a. Although detailed illustration is omitted, a plurality of gas introduction ports 20b are provided at intervals in the extending direction of the gas introduction passage 20a (the direction orthogonal to the plane of FIG. 2). Each gas inlet 20b reaches the inner side surface of the long side frame portion 21 and is opened.
The processing gas source 4 stores a processing gas corresponding to the processing purpose.

  A ground side cooling path 20 c is formed below the gas introduction path 20 a inside the frame 20. A cooling medium from a cooling medium supply means (not shown) is passed through the ground side cooling path 20c. For example, water is used as the cooling medium.

  As shown in FIGS. 2 and 4, an electric field application side dielectric member 50 is provided inside the processing head 1. The dielectric member 50 integrally includes a bottom plate portion 51 and a pair of side wall portions 52 and 52. The bottom plate portion 51 extends in the longitudinal direction of the processing head 1. The pair of side wall portions 52 and 52 protrude upward from the edges on both sides in the short direction of the bottom plate portion 51. The bottom plate portion 51 and the side wall portions 52 and 52 are combined, and the dielectric member 50 has a substantially U-shaped cross section.

  The bottom plate portion 51 plays a role as a dielectric layer provided on the discharge generation surface (lower surface) of the electrode 30 in order to stabilize the discharge. The bottom plate portion 51 is separate from the electrode 30 and can be separated.

  As shown in FIG. 2, the upper end surface of the side wall portion 52 is brought into contact with the lower surface of the upper lid member 10. The side wall 52 is connected to the upper lid member 10 by bolts (not shown).

  A side gap 1 c is formed between the outer side surface of each side wall portion 52 and the inner side surface of the long side frame portion 21. A gas inlet 20b is connected to the upper end of the side gap 1c.

  The electric field application electrode 30 is accommodated in the dielectric member 50. The electrode 30 is made of a metal such as stainless steel or aluminum. The electrode 30 has a flat plate shape in which the longitudinal direction is in the left-right direction in FIG. 1 (the same direction as the longitudinal direction of the processing head 1) and the short direction is in the direction perpendicular to the plane of FIG. As shown in FIG. 2, the electrode 30 is connected to the power supply 3 via the feeder 3a. The electrode 30 is placed on the upper surface of the bottom plate portion 51 of the dielectric member 50. Thereby, the lower surface (electric field application side discharge surface) of the electrode 30 is covered with the plate part 51 as a solid dielectric layer.

  As shown in FIG. 2, an electric field application side cooling path 32 c is formed inside the electrode 30. The cooling path 32 c extends in the longitudinal direction of the electrode 30. A cooling medium from a cooling medium supply means (not shown) is passed through the cooling path 32c. For example, water is used as the cooling medium.

  As shown in FIG. 1, end pieces 35 are provided between both end faces in the longitudinal direction of the electrode 30 and the short side frame portion 22. The end piece 35 is made of ceramic (insulator) such as alumina. The electrode 30 and the frame 20 are insulated by the end piece 35.

  A slight clearance is provided between the both end faces of the electrode 30 in the longitudinal direction and the end piece 35 to allow the electrode 30 to stretch and deform. The joint between the end piece 35 and the electric field application side dielectric member 50 is completely caulked with an adhesive or the like.

  As shown in FIG. 2, both side surfaces of the electrode 30 in the short direction face the side wall portions 52 of the dielectric member 50. A side insulating gap 1 d is formed between the electrode 30 and the side wall 52.

  The upper lid member 10 is placed over the electrode 30. An upper insulating gap 1 e is formed between the electrode 30 and the upper lid member 10. The upper insulating gap 1e and the side insulating gap 1d are connected to each other.

  As shown in FIGS. 1 to 4, a ground electrode 40 is provided on the bottom of the processing head 1. The ground electrode 40 has a flat plate shape in which the longitudinal direction is in the left-right direction in FIG. 1 (the same direction as the longitudinal direction of the processing head 1) and the short direction is in the direction perpendicular to the plane of FIG. The ground electrode 40 blocks the internal space of the frame 20 from below. The ground electrode 40 also serves as the bottom plate of the processing head 1. The peripheral portion of the ground electrode 40 is in contact with the lower surface of the frame 20. The frame 20 and the ground electrode 40 are connected by a bolt (not shown). The bolt connecting the frame 20 and the ground electrode 40 preferably has a head portion facing upward and a leg portion screwed into the ground electrode 40.

The ground electrode 40 is made of a metal having high heat resistance and corrosion resistance such as stainless steel. The ground electrode 40 is electrically grounded via the ground line 3b (FIG. 2).
The upper surface of the ground electrode 40 is a ground-side discharge surface 42 facing the electric field application electrode 30 (surface to generate a discharge with the electric field application electrode 30).
The ground electrode 40 faces the workpiece placement portion 2 and thus the workpiece 9, and forms a treatment space 1 a between the ground electrode 40 and the workpiece 9. The lower surface of the ground electrode 40 (surface opposite to the discharge surface 42) is a processing surface 43 facing the workpiece 9 (surface on which the processing space 1a is to be defined with the workpiece 9).

  A ground-side dielectric member 60 is provided above the ground electrode 40. The dielectric member 60 is made of ceramic (solid dielectric) such as alumina. The dielectric member 60 has a flat plate shape extending in the same direction as the ground electrode 40. The dielectric member 60 is placed on the ground electrode 40. The lower surface of the dielectric member 60 is a contact surface 63 that contacts the discharge surface 42 (upper surface) of the ground electrode 40. The dielectric member 60 covers the discharge surface 42 of the ground electrode 40 and serves as a dielectric layer that stabilizes the discharge.

  As shown in FIGS. 1 and 2, the dielectric member 60 is accommodated inside the frame 20. A sufficient clearance is formed between the outer peripheral edge of the dielectric member 60 and the inner peripheral surface of the frame 20 to allow expansion of the dielectric member 60 and to accommodate the dielectric member 60 in the frame 20. The size d1 of the clearance is a level that enables the accommodating operation of the dielectric member 60, and is, for example, less than d1 = 1 mm. The frame 20 serves as a position restricting means for restricting the horizontal position of the dielectric member 60 with respect to the ground electrode 40. The position of the dielectric member 60 is allowed to have an error corresponding to the clearance size d1 (<1 mm). When the dielectric member 60 is disposed at a regular position, a gap having a width that is exactly half the clearance is formed between the peripheral end surface of the dielectric member 60 and the inner peripheral surface of the frame 20. The

  As shown in FIG. 1 and FIG. 4, convex portions 64 projecting upward are formed at both end edges in the longitudinal direction of the dielectric member 60. The convex portion 64 extends along the edge of the dielectric member 60. Both ends in the longitudinal direction of the bottom plate portion 51 of the electric field application side dielectric member 50 are placed on the convex portions 64.

  As shown in FIGS. 1 and 2, a narrow lower gap 1 b is formed between the bottom plate portion 51 of the electric field application side dielectric member 50 and the ground side dielectric member 60. As will be described later, the central portion of the lower gap 1b becomes a discharge space 1p. The upper surface of the ground side dielectric member 60 faces the electric field application side dielectric member 50 and thus the electric field application electrode 30. The upper surface of the ground-side dielectric member 60 is an defining surface 62 that defines the discharge space 1p. As shown in FIG. 2, both ends in the short direction of the lower gap 1b are respectively connected to the lower ends of the side gaps 1c.

The ejection structure of the processing head 1 will be described.
As shown in FIGS. 1 to 4, a plurality of ejection guide holes 61 are formed in the ground side dielectric member 60. As shown in FIG. 5, each ejection guide hole 61 penetrates in the thickness direction from the upper surface (the defined surface 62 of the discharge space 1 p) of the dielectric member 60 to the lower surface (the contact surface 63 with the ground electrode 40). Yes. The upper end portion of the ejection guide hole 61 is continuous with the discharge space 1p. The inner surface of the ejection guide hole 61 is a cylindrical surface having a diameter of about φ = 0.1 mm to 2 mm, for example.

  As shown in FIG. 3, the plurality of ejection guide holes 61 are arranged in a line at equal intervals in the longitudinal direction of the processing head 1. These rows of the ejection guide holes 61 are arranged at the center in the width direction of the processing head 1. The pitch P of the ejection guide holes 61 is, for example, about P = 2 mm to 12 mm.

As shown in FIGS. 1 to 4, the ground electrode 40 has a single jet port 41. The ejection port 41 is disposed at the center in the width direction of the processing head 1 and has a slit shape (long hole shape) extending in the longitudinal direction of the processing head 1, that is, in the arrangement direction of the ejection guide holes 61. As shown in FIG. 5, the jet nozzle 41 penetrates the ground electrode 40 from the upper surface (discharge surface 42) to the lower surface (treatment surface 43) in the thickness direction. The lower end of the spout 41 is connected to the processing space 1a.
As shown in FIG. 3, the width W (dimension in the direction orthogonal to the extending direction) of the ejection port 41 is, for example, about W = 0.3 mm to 7 mm.

As shown in FIGS. 1 and 3, all (plural) ejection guide holes 41 of the dielectric member 60 are all connected to one slit-shaped ejection port 41. The opening area of the ejection port 41 is larger than the total opening area of all (a plurality of) ejection guide holes 61.
The opening area (cross-sectional area) of the ejection port 41 is constant regardless of the position of the ground electrode 40 in the thickness direction. The opening area (cross-sectional area) of the ejection guide hole 61 is constant regardless of the position of the dielectric member 60 in the thickness direction.

  Both end portions in the longitudinal direction of the slit-like ejection ports 41 extend outward from the row of ejection guide holes 41 in the longitudinal direction (the direction in which the ejection guide holes 41 are arranged). As shown in FIG. 3, all (a plurality of) ejection guide holes 41 are arranged inside the ejection port 41 in a bottom view. That is, as shown in FIGS. 3 and 5, the peripheral portion of the ejection guide hole 41 of the dielectric member 60 is disposed inside the edge of the ejection port 41. When viewed from above (on the side of the electric field application electrode 30), the dielectric member 60 covers the edge of the ejection port 41 of the ground electrode 40 over the entire circumference. As shown in FIG. 5, a stepped surface 63 b orthogonal to the inner surface of the ejection port 41 is formed by the peripheral portion of the ejection guide hole 41 of the dielectric member 60.

As shown in FIGS. 3 and 6A, when the dielectric member 60 is accurately positioned with respect to the ground electrode 40, the center of each ejection guide hole 61 is on the center line L of the slit-shaped ejection port 41 ( It is arranged at the center of the direction intersecting with the arrangement direction. As shown in FIG. 6A, the dimension W in the width direction of the slit-shaped ejection port 41 is larger than the same dimension in the ejection guide hole 61, that is, the diameter φ of the ejection guide hole 61.
W> φ Formula (1)
The difference Δ (= W−φ) between the width W of the ejection port 41 and the diameter φ of the ejection guide hole 61 is preferably about Δ = 0.1 to 5 mm, and more preferably about Δ = 2 mm. The dimensional difference Δ is preferably larger than twice the tolerance d1 (<1 mm) of the positioning error of the dielectric member 60.
Δ> 2 × d1 Formula (2)

Further, in FIG. 6A, the width W of the ejection port 41 is larger than the pitch P of the ejection guide holes 61 and satisfies the following equation.
W ≧ P Formula (3)
The pitch P of the ejection guide holes 61 is naturally larger than the diameter φ (P> φ).

The reason why the expression (3) can be satisfied is that the correspondence relationship between the ejection port 41 and the ejection guide hole 61 is not one-to-one but one-to-multiple. As shown in FIG. 6 (b), when the ejection port 41 ′ and the ejection guide hole 61 ′ have a one-to-one correspondence, the pitch P ′ of the ejection guide hole 61 ′ is equal to the diameter W ′ ( It is necessary to make it larger than the width W)). Otherwise, as shown by the phantom line in FIG. 6 (a), the adjacent jet nozzles 41 ′ and 41 ′ interfere with each other.
Note that the formula (3) is not necessarily satisfied. The pitch P of the ejection guide holes 61 may be larger than the width of the ejection guide holes 41 (P> W or P ≧ W). In the case of a surface treatment such as cleaning where uniformity is not strictly required, it is sufficient if the expression (1) is satisfied.

A procedure for assembling the processing head 1 will be described.
The frame 20 is disposed on the bottom plate, that is, the ground electrode 40. The ground side dielectric member 60 is accommodated inside the frame 20 and placed on the upper surface 42 of the ground electrode 40. Then, all (a plurality of) the ejection guide holes 61 communicate with one slit-shaped ejection port 41. Since an extremely small clearance (d1 <1 mm) is formed between the dielectric member 60 and the frame 20, the dielectric member 60 can be easily accommodated in the frame 20, and can be positioned almost accurately with respect to the ground electrode 40. Can do. Even if there is a positioning error of the dielectric member 60, all of the difference (Δ> 2 × d1) between the dimensional difference Δ between the width W of the ejection port 41 and the diameter φ of the ejection guide hole 61 and the clearance d1 (Δ> 2 × d1). The entire circumference of the plurality of ejection guide holes 61 can be always located inside one slit-like ejection port 41. Therefore, the dielectric member 60 can always cover the entire periphery of the upper end edge 41a of the ejection port 41 of the ground electrode 40 when viewed from above (the electric field application electrode 30 side).

  Subsequently, the electric field application side dielectric member 50 is inserted into the frame 20. Both end portions in the longitudinal direction of the electric field application side dielectric member 50 are placed on the convex portion 64. The electric field application electrode 30 is placed on the bottom plate portion 51 of the electric field application side dielectric member 50. End pieces 35 are disposed at both ends of the electric field applying electrode 30 in the longitudinal direction. The seam between the end piece 35 and the electric field application side dielectric member 50 is completely caulked with an adhesive or the like. Next, the upper lid member 10 is placed on the members 20, 30 and 50. And each member is bolted and connected.

  When performing the surface treatment with the plasma processing apparatus having the above-described configuration, the workpiece 9 is set on the placement unit 2. Then, the processing gas from the processing gas source 4 is supplied to the gas introduction path 20a of the processing head 1 through the gas supply path 4a. This processing gas uniformly flows into the side gap 1c from the plurality of gas inlets 20b and is further introduced into the lower gap 1b.

  In parallel, a voltage is supplied from the power source 3 to the electric field applying electrode 30. As a result, an atmospheric pressure glow discharge is generated between the electric field applying electrode 30 and the ground electrode 40, the central portion of the lower gap 1b becomes the discharge space 1p, and the processing gas in the space 1p is turned into plasma (decomposition, excitation, activation) Including radicalization, ionization).

  The plasma-ized processing gas is ejected from the ejection port 41 to the lower processing space 1 a through the ejection guide hole 61 and comes into contact with the workpiece 9. As a result, a reaction occurs on the surface of the workpiece 9 and a desired surface treatment is performed. Furthermore, by moving the placement unit 2 relative to the processing head 1, the entire workpiece 9 can be processed.

  When viewed from the side (upper side) of the electric field applying electrode 30, the ejection port 41 of the ground electrode 40 is hidden by the dielectric member 60 around the ejection guide hole 61. It can prevent falling to 41a. Thereby, generation | occurrence | production of a metal contamination and a particle can be blocked | prevented, and it can prevent that these metal contamination and a particle adhere to the to-be-processed object 9. FIG.

  The plurality of ejection guide holes 61 inside one ejection port 41 can sufficiently reduce the pitch P. As shown in Expression (2), the pitch P of the ejection guide holes 61 can be made smaller than the width W of the ejection ports 41. As derived from the equations (2) and (3), the pitch P of the ejection guide holes 61 can be increased by 2 mm of the diameter φ to be equal to or less. Therefore, processing omission or processing unevenness can be sufficiently prevented. Even when the relative movement speed of the workpiece 9 with respect to the processing head 1 is a low speed of, for example, 1 mm / min or less, uneven processing can be reliably prevented.

Next, another embodiment of the present invention will be described. Regarding the configurations described in the following embodiments, the same reference numerals are given to the drawings, and description thereof will be omitted as appropriate.
As shown in FIG. 7, the ground electrode 40 may be provided with a plurality of slit-shaped (long hole-shaped) ejection ports 41. The longitudinal direction of the slit-shaped ejection port 41 may intersect the longitudinal direction of the processing head 1.

  In the second embodiment shown in FIG. 7, a plurality of slit-shaped ejection ports 41 are arranged at regular intervals in the longitudinal direction of the processing head 1. The longitudinal direction of the slit-shaped ejection port 41 is inclined with respect to the longitudinal direction of the processing head 1. A plurality of ejection guide holes 61 are arranged in a row at a short pitch inside each ejection port 41. The arrangement direction of the ejection guide holes 61 coincides with the longitudinal direction of the ejection port 41.

  In 3rd Embodiment shown in FIG. 8, the length of the longitudinal direction of the jet nozzle 41 is smaller than above-mentioned embodiment (FIG. 3, FIG. 7). A large number (a plurality) of the ejection ports 41 are formed in the ground electrode 40. The ejection ports 41 are arranged in a line in the longitudinal direction of the processing head 1 and are arranged in a line in a direction oblique to the longitudinal direction of the processing head 1. The longitudinal direction of each ejection port 41 coincides with the longitudinal direction of the processing head 1. Two (plural) ejection guide holes 61 are arranged inside each ejection port 41. The two ejection guide holes 61 are separated in the major axis direction of the ejection port 41.

The present invention is not limited to the above embodiment, and various modifications can be made.
For example, the pitch P of the ejection guide holes 61 may be larger than the width W of the ejection ports 41 (P> W). The intervals between the ejection guide holes 61 need not be equal.
The plurality of jet nozzles 41 may be arranged at intervals in the width direction perpendicular to the longitudinal direction of the processing head 1 with the longitudinal direction thereof directed to the longitudinal direction of the processing head 1.
In FIG. 7, the plurality of jet nozzles 41 may be arranged with their longitudinal directions straight in the width direction of the processing head 1 and spaced apart from each other in the longitudinal direction of the processing head 1.
In FIG. 8, the longitudinal direction of each ejection port 41 may be oblique or orthogonal to the longitudinal direction of the processing head 1, and the plurality of ejection ports 41 may be arranged in a square lattice shape or a triangular lattice shape. .
The spout 41 does not need to extend linearly over the entire length, may be bent, or may be curved.

The ejection guide holes 61 are not limited to one line and may be arranged in two or more lines inside the one ejection port 41. The ejection guide holes 61 may be randomly arranged inside one ejection port 41.
The shape of the ejection guide hole 61 is not limited to a perfect circle, but may be an oval, a polygon, or an arbitrary shape.

  The spout 41 may be oval. The jet nozzle 41 is not limited to the shape of a long hole (including a slit shape and an elliptical shape) as long as a plurality of jet nozzles 41 are arranged on the inner side thereof, and may be a perfect circle or a polygon. It may have an arbitrary shape.

It is only necessary that the openings of at least the contact surfaces 63 of the plurality of ejection guide holes 61 are accommodated at least inside the opening of the ejection port 41 to the discharge surface 42. It is only necessary that the opening area of at least the discharge surface 42 of the ejection port 41 is larger than the total opening area of at least the contact surface 43 of the plurality of ejection guide holes 61. In the first embodiment, the inner peripheral surface of the ejection port 41 is vertical throughout the thickness direction of the ground electrode 41, and the width of the ejection port 41 is constant throughout the thickness direction of the ground electrode 41. However, the present invention is not limited to this, and the inner peripheral surface of the ejection port 41 may be a slope so that the width of the ejection port 41 becomes wider or narrower downward. A step may be formed on the inner peripheral surface of the ejection port 41 in the middle of the thickness direction of the ground electrode 41. The inner peripheral surface of the ejection guide hole 61 is not limited to a vertical cylindrical surface, and may have a tapered shape that increases or decreases in diameter downward. A step may be formed midway in the penetration direction of the ejection guide hole 61.
The axis of the ejection guide hole 61 is not limited to being orthogonal to the contact surface, and may be inclined.

  An insulating covering member (bush) may be provided on the inner peripheral surface of the jet nozzle 41.

  The present invention can be applied to various surface treatments such as cleaning, surface modification (hydrophilization, water repellency, etc.), etching, and film formation. The present invention is not limited to plasma processing near atmospheric pressure, and can also be applied to plasma processing under vacuum.

  The present invention is applicable to, for example, surface treatment in a manufacturing process of a glass substrate for a flat panel display or a semiconductor substrate.

It is side surface sectional drawing which shows the atmospheric pressure plasma processing apparatus which concerns on 1st Embodiment of this invention along the II line | wire of FIG. It is front sectional drawing of the processing head of the said atmospheric pressure plasma processing apparatus which follows the II-II line of FIG. FIG. 3 is a bottom view of the processing head taken along line III-III in FIG. 2. It is a disassembled perspective view of the said processing head. It is front sectional drawing which expands and shows the process gas ejection structure of the said process head. (A) is an enlarged bottom view of the process gas ejection structure of the said process head. (B) is an enlarged bottom view of the ejection structure of the reference form in which the ejection port and the ejection guide hole are in one-to-one correspondence. It is a bottom view of the processing head concerning a 2nd embodiment of the present invention. It is a bottom view of the processing head concerning a 3rd embodiment of the present invention.

Explanation of symbols

9 Processed object 1 Processing head 1a Processing space 1b Lower clearance 1c Side clearance 1d Side insulating clearance 1e Upper insulating clearance 1p Discharge space 2 Processed object placement section 3 Power supply 3a Feed line 3b Grounding wire 4 Processing gas source 10 Upper cover member 20 Frame 20a Gas introduction path 20b Gas introduction port 20c Ground side cooling path 21 Long side frame part 22 Short side frame part 30 Electric field application electrode 32c Electric field application side cooling path 35 End piece 40 Ground electrode 41 Jet port 41a Discharge surface of jet port Side edge 42 discharge surface 43 treatment surface 50 electric field application side dielectric member 51 bottom plate portion 52 side wall portion 60 dielectric member 61 ejection guide hole 62 defining surface 63 contact surface 63b step 64 convex portion d1 clearance (allowable positioning error)
φ Diameter of jet guide hole P Pitch of jet guide hole W Width of jet port L Center line of jet port

Claims (6)

In an apparatus for performing plasma surface treatment by forming a processing gas into plasma in a discharge space and ejecting the gas, bringing it into contact with an object disposed in an object disposition portion outside the discharge space,
An electric field applying electrode connected to a power source;
A grounding electrode having a discharge surface facing the electric field applying electrode and a processing surface facing the workpiece placement portion, and being electrically grounded;
A dielectric member made of a solid dielectric having an abutting surface applied to the discharge surface of the ground electrode and an defining surface that faces the electric field applying electrode and defines the discharge space;
The dielectric member is formed with a plurality of ejection guide holes penetrating from the defining surface to the contact surface, and the ground electrode is formed with an ejection port penetrating from the discharge surface to the processing surface. The opening area of the ejection port to the discharge surface is larger than the total opening area of the plurality of ejection guide holes to the contact surface, and the plurality of ejection guide holes are all connected to one ejection port. A plasma processing apparatus.   2. The plasma processing apparatus according to claim 1, wherein the plurality of ejection guide holes are arranged in a row, and the ejection port has an elongated hole shape extending in an arrangement direction of the plurality of ejection guide holes.   The plasma processing apparatus according to claim 2, wherein a pitch of the ejection guide holes is equal to or less than a dimension in a width direction orthogonal to an extending direction of the opening of the ejection port to the discharge surface.   The width direction dimension orthogonal to the extending direction of the opening to the discharge surface of the ejection port is larger than the dimension in the same direction as the width direction of the opening to the contact surface of the ejection guide hole. The plasma processing apparatus according to claim 2 or 3.   The plasma processing apparatus according to claim 4, wherein a difference between the two dimensions is 0.1 to 5 mm.   The plasma processing apparatus according to claim 1, wherein the center of each ejection guide hole is disposed at the center in the width direction orthogonal to the extending direction of the ejection port.

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