KR20090108738A - Plasma processing apparatus - Google Patents

Abstract

[PROBLEMS] To eliminate abnormal discharge onto an inner surface of an ejection port on a ground electrode of a plasma processing apparatus. [MEANS FOR SOLVING PROBLEMS] A dielectric member (60) is arranged on a discharge surface (42), which is of a ground electrode (40) of a plasma processing apparatus and facing an electric field applying electrode (30). On the dielectric member (60), an ejection guide hole (62) continuous to a discharge space (1p) between the electrodes is formed, and on the ground electrode (40), an ejection port (41) continuous to the ejection guide hole (62) is formed. An inner surface of the ejection guide hole (62) on the dielectric member (60) is protruded from an inner surface of the ejection port (41) on the ground electrode (40). On the dielectric member (60), a step surface (64) is extended as the same surface from an abutting surface (63) which abuts to the ground electrode (40).

Description

Plasma Processing Equipment {PLASMA PROCESSING APPARATUS}

The present invention relates to a plasma processing apparatus.

For example, Patent Document 1 below describes a plasma processing apparatus in which a pair of electrodes is disposed to face up and down. The upper electrode is connected to a power source to form an electric field application electrode. The lower electrode is electrically grounded to form a ground electrode. An electric field is applied between these electrodes to generate atmospheric glow discharge, and at the same time, a processing gas is introduced to make plasma. The slit-shaped jet opening is formed in the lower ground electrode. The processing gas is jetted downward from the jet port. The to-be-processed object is arrange | positioned under the ground electrode. The processing gas from the jet port is sprayed on the object to be treated, and the surface treatment is performed.

On the upper surface of the ground electrode (opposed to the electric field applying electrode), a solid dielectric layer containing a thermal sprayed coating of alumina is formed.

Patent Document 1: Japanese Patent Application Laid-Open No. 2004-006211

<Start of invention>

Problems to be Solved by the Invention

In the plasma processing apparatus of the above structure, if the inner surface of the ejection port of the ground electrode made of metal is exposed, an arc may be generated there. In particular, an electric field was concentrated at the end edge of the electrode application electrode side of the ejection opening, and a discharge with stronger emission intensity occurred at the end edge thereof, or an arc occurred therein. Then, there was a problem that metal contamination or particles are generated and adhered to the workpiece.

Means for solving the problem

MEANS TO SOLVE THE PROBLEM In order to solve the said subject, this invention is the apparatus which plasma-processes and discharges a process gas in a discharge space, and makes plasma surface treatment by making it contact a to-be-processed object arrange | positioned in the to-be-processed object placement part of the said discharge space. ,

An electric field applying electrode (hot electrode) connected to a power supply,

An electrically grounded ground electrode (earth electrode) having a discharge surface facing the electric field application electrode and a processing surface facing the object placement portion;

A dielectric member on the ground side made of a solid dielectric that contacts the discharge surface of the ground electrode and simultaneously partitions the discharge space facing the field applying electrode.

The dielectric member is provided with a spray coating continuous to the discharge space.

The ground electrode is provided with a jet port which is continuous with the jet coating and penetrates from the discharge surface to the processing surface,

An inner surface of the jet coating in the dielectric member protrudes radially inward of the jet port from an end edge of the discharge surface side of the internal surface of the jet port in the ground electrode,

The dielectric member has a contact surface in contact with the discharge surface of the ground electrode and a step surface extending from the contact surface to the same surface to form a step between the inner surface of the spray coating and the inner surface of the spray port. do.

As a result, abnormal discharge such as an arc can be prevented from occurring at the edge of the discharging surface side of the inner surface of the ejection opening in the ground electrode, and the occurrence of metal contamination and particles can be prevented, and these metal contents can be prevented. Nation or particles can be prevented from adhering to the workpiece.

The size and shape of the jet port may be constant in the penetrating direction (thickness direction of the ground electrode) of the jet port. As a result, the ejection opening can be easily formed, and abnormal discharge such as an arc can be prevented from occurring at any portion of the inner surface as well as the end edge of the discharge side of the inner surface of the ejection opening.

The size and shape of the jet coating may be constant in the penetration direction (thickness direction of the dielectric member) of the jet coating. Thereby, spray coating can be formed easily.

The magnitude | size at the edge part of the said process surface side of the said jet port may be smaller than the magnitude | size at the edge part at the said discharge surface side. As a result, an abnormal discharge such as an arc can be prevented from occurring at the end edge of the discharge surface side of the inner surface of the ejection opening at the ground electrode, and an intervention of an external atmosphere into the ejection opening can be prevented. The blowing moment of can be ensured, and the processing efficiency can be improved.

As the size of the jet port is close to the treatment surface, it may be gradually decreased. Thereby, electric field concentration can be prevented from occurring on the inner surface of the jet port, and it can reliably prevent abnormal discharge from occurring.

The size and shape at the end of the jetting port at the treatment surface side may substantially match the size and shape of the jetting coating. As a result, the intervention of the external atmosphere can be sufficiently prevented, the momentum of the processing gas can be sufficiently secured, and the abnormal discharge can be reliably prevented from occurring on the inner surface of the jet port.

It is preferable to further include position regulating means for positioning the dielectric member while allowing an error in a plane parallel to the discharge surface with respect to the ground electrode. Accordingly, the dielectric member and the ground electrode can be thermally expanded independently of each other, so that the dielectric member can be prevented from being damaged due to the expansion difference between them.

It is preferable that the width | variety along the said protrusion direction of the said step surface in the state which positioned the said dielectric member in a normal position is larger than the allowable amount of the said error. As a result, even if there is a positioning error of the dielectric member, it is possible to reliably prevent the occurrence of abnormal discharge.

The dielectric member may be formed of an insulator separate from the dielectric member, and may further include a covering member provided to cover the inner surface of the blowout port of the ground electrode. As a result, it is possible to more reliably prevent the occurrence of abnormal discharge on the inner surface of the jet port.

It is preferable that the thickness of the covering member is approximately equal to the width along the protruding direction of the stepped surface. As a result, the inner surface of the dielectric spraying coating and the inner wall of the covering member can be the same surface, and defects such as corners of the covering member can be reliably prevented, and generation of particles can be prevented.

The present invention is suitable for plasma treatment at about atmospheric pressure (at normal pressure). Here, the near atmospheric pressure (almost normal pressure) refers to the range of 1.013 × 10 ⁴ to 50.663 × 10 ⁴ Pa, and considering the ease of pressure adjustment and the simplified device configuration, 1.333 × 10 ⁴ to 10.664 × 10 ⁴ Pa Is preferable and 9.331 * 10 <^4> -10.397 * 10 <^4> Pa is more preferable.

Effect of the Invention

According to the present invention, occurrence of abnormal discharge such as an arc can be prevented from occurring at the end edge of the discharge surface side of the inner surface of the ejection port on the ground electrode, thereby preventing the generation of particles.

1 is a side sectional view showing an atmospheric pressure plasma processing apparatus according to a first embodiment of the present invention along the line I-I of FIG. 2.

FIG. 2 is a front sectional view of a processing head of the atmospheric pressure plasma processing apparatus along the line II-II of FIG. 1.

3 is an exploded perspective view of the processing head.

4 is a front sectional view showing the electrode part of the processing head in an enlarged manner, and (b) is a plan view along the line IVb-1Vb of (a).

FIG. 5 shows a case where the ground-side dielectric member is displaced in FIG. 4 by a solid line, and shows a normal position by an imaginary line, (a) is an enlarged sectional view of the electrode portion, and (b) is (a) It is a top view along the Vb-Vb line of this.

Fig. 6 (a) is a bottom view showing an example of an arrangement structure of the jet port and the jet coating of the processing head.

Fig. 6 (b) is a bottom view showing an example of an arrangement structure of the jet port and the jet coating of the processing head.

FIG. 7: shows the modification of the ejection opening of the said electrode part, (a) is an expanded sectional view, (b) is a top view along the Vlb-Vlb line of (a).

8 is an enlarged cross-sectional view showing a modification of the jet port of the electrode portion.

9 is an enlarged cross-sectional view showing a modification of the jet port of the electrode portion.

10 is a cross-sectional view showing a modification of the jet structure of the treatment head.

It is a bottom view which shows the modification of the shape of the jet opening of the said process head, and jet coating.

It is a bottom view which shows the modification of the ejection opening and ejection coating of the said processing head.

Fig. 13 is a bottom view showing a modification of the jet port and the jet coating of the treatment head.

Fig. 14 is a bottom view showing a modification of the jet port and the jet coating of the treatment head.

Explanation of the sign

W: To-be-processed object

1: treatment head

1a: processing space

1p: discharge space

2: object to be processed

3: power

20: frame (position control means)

30: field applied electrode

40: bottom plate (grounding electrode)

41: spout

41a: end edge of the discharge surface of the jet port

41b: end edge of the treated surface side of the jet port

42: discharge surface

43: treatment surface

60: grounding dielectric member

62: blowout coating

63: contact surface

64: step surface

70: covering member

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described according to drawing.

1 to 3 show a first embodiment of the present invention. The atmospheric pressure plasma processing apparatus is provided with the process head 1 and the to-be-processed object part 2. The to-be-processed object placement part 2 is comprised by the stage and conveyor, and the to-be-processed object W is arrange | positioned above it. The to-be-processed object W is a glass substrate or a semiconductor substrate, for example.

The to-be-processed object placement part 2 is able to convey the to-be-processed object W to the orthogonal direction of the paper of FIG. The to-be-processed object W may be fixed in position, and the process head 1 may be made to move in the orthogonal direction of the paper of FIG.

The processing head 1 is supported by the mount which is not shown in figure, and is located in the upper side of the to-be-processed object placement part 2. As shown in FIG. The processing head 1 includes an upper cover member 10, a frame 20, an electric field applying electrode 30, and a bottom plate 40, and has one direction (left-right direction in FIG. 1 and paper-orthogonal direction in FIG. 2). Extends.

The upper lid member 10 is made of a resin (insulator) having high corrosion resistance and extends in the longitudinal direction of the treatment head 1.

As shown in FIG. 3, the frame 20 has a pair of long side frame portions 21 and a pair of short side frame portions 22, and is rectangular in plan view with an open inside. The long side frame portion 21 constitutes the long side of the processing head 1. The short side frame portion 22 constitutes a short side of the processing head 1. The peripheral part of the upper lid member 10 is placed on the upper surface of the frame 20. As shown in FIG. 2, the short bolt 91 penetrates the upper lid member 10 vertically and is twisted into the frame 20. The upper cover member 10 and the frame 20 are connected by the bolt 91. The upper lid member 10 blocks the internal space of the frame 20 from above.

The gas introduction passage 20a is formed in the pair of long side frame portions 21, respectively. The gas introduction passage 20a extends in the longitudinal direction of the processing head 1. The gas supply passage 4a from the processing gas source 4 is continuous at one end of the gas introduction passage 20a. The gas introduction port 20b branches off from the side of the gas introduction passage 20a. The gas inlet 20b is provided in multiple numbers at intervals in the extending direction (the orthogonal direction of the paper surface of FIG. 2) of the gas introduction path 20a. Each gas inlet 20b reaches the inner side surface of the long side frame part 21, and is open.

In addition, the processing gas source 4 stores a processing gas suitable for the processing purpose.

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

An electric field application side dielectric member 50 is provided inside the processing head 1. The dielectric member 50 has the bottom plate part 51 and a pair of side wall parts 52 and 52 integrally. The bottom plate part 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. These bottom plate portions 51 and side wall portions 52 and 52 are combined to form a substantially U-shaped cross section of the dielectric member 50.

The bottom plate portion 51 is disposed on the discharge generating surface of the electrode 30 and serves as a dielectric layer for stabilizing the discharge, and is separated from the electrode 30 separately.

As shown in FIG. 2, a pair of side gaps 1c are formed between the pair of side wall portions 52 and the long side frame portion 21. The gas inlet 20b is continuous in the upper end part of each side clearance gap 1c.

The bolt 93 (FIG. 2) penetrates the upper lid member 10 vertically and is screwed into the side wall portion 52. The upper cover member 10 and the dielectric member 50 are connected by the bolt 93.

The electric field application electrode 30 is accommodated in the dielectric member 50. The electrode 30 is comprised with metals, such as stainless steel and aluminum. The electrode 30 has a flat plate shape in which the long direction is oriented in the left and right direction (the same direction as the long direction of the processing head 1) in FIG. 1 and the short direction is in the orthogonal direction of the paper in FIG. As shown in FIG. 2, the electrode 30 is connected to the power supply 3 via the feed line 3a. This electrode 30 is placed on the upper surface of the bottom plate portion 51 of the dielectric member 50. As a result, the lower surface (the electric field application side discharge surface) of the electrode 30 is covered with the plate portion 51 as a solid dielectric layer.

An electric field application side cooling path 32c is formed inside the electrode 30. The cooling path 32c extends in the longitudinal direction of the electrode 30. In the cooling path 32c, a cooling medium from a cooling medium supply means (not shown) passes. For example, water is used as the cooling medium.

As shown in FIG. 1, the end piece 35 is provided between the both ends of the longitudinal direction of the electrode 30, and the short side frame part 22. As shown in FIG. The end piece 35 is made of a 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 end face 35 of the longitudinal direction of the electrode 30 and the end piece 35 to allow elongation deformation of the electrode 30. The joint between the end piece 35 and the field application side dielectric member 50 is completely caulked with an adhesive or the like.

As shown in FIG. 2, both side surfaces in the short direction of the electrode 30 face the side wall portion 52 of the dielectric member 50. The side insulation clearance gap 1d is formed between these electrodes 30 and the side wall portion 52.

The upper lid member 10 is covered on the upper side of the electrode 30. An upper insulating gap 1e is formed between the electrode 30 and the upper lid member 10. The upper insulation gap 1e and the side insulation gap 1d are continuous with each other.

1 to 3, the bottom plate 40 is provided at the bottom of the processing head 1. The bottom plate 40 has a flat plate shape in which the long direction is directed in the left and right direction (the same direction as the long direction of the processing head 1) in FIG. 1 and the short direction is in the orthogonal direction of the paper in FIG. While the periphery of the bottom plate 40 is in contact with the lower surface of the frame 20, a slightly longer bolt 92 (FIG. 2) vertically penetrates the top cover member 10 and the frame 20 so that the bottom plate 40 Is twisted around the periphery. The bottom plate 40 is connected to the frame 20 by bolts 92. The bottom plate 40 blocks the internal space of the frame 20 from below.

The bottom plate 40 is made of a metal having high heat resistance and corrosion resistance, such as stainless steel. The bottom plate 40 is electrically grounded through the ground wire 3b (FIG. 2). As a result, the bottom plate 40 serves as a ground electrode for the electric field application electrode 30. Hereinafter, the bottom plate 40 is appropriately referred to as "ground electrode 40".

The upper surface of the ground electrode 40 is a ground-side discharge surface 42 facing the electric field application electrode 30 (a surface on which discharge must be generated between the electric field application electrode 30).

The ground electrode 40 faces the object to be processed portion 2 and further, the object W, and forms a processing space 1a between the object W. The lower surface of the ground electrode 40 (the surface opposite to the discharge surface 42) is the treatment surface 43 facing the object W (the surface where the treatment space 1a should be partitioned between the object W). It is.

The ground side dielectric member 60 is provided on the discharge surface (upper surface) 42 of the ground electrode 40. The dielectric member 60 is made of a 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 covers the discharge surface 42 of the ground electrode 40 and serves as a dielectric layer to stabilize the discharge.

The dielectric member 60 is housed inside the frame 20. Clearance is formed between the outer periphery of the dielectric member 60 and the inner peripheral surface of the frame 20 to allow expansion of the dielectric member 60 or to accommodate the dielectric member 60 in the frame 20. have. The magnitude d1 of the clearance is such as to allow the accommodation operation of the dielectric member 60, for example, d1 = less than 1 mm. The frame 20 is a position regulating means for regulating the position of the dielectric member 60 with respect to the upper surface 42 of the ground electrode 40. The position of the dielectric member 60 allows an error of the minute corresponding to the clearance size d1 (<1 mm) (see Fig. 5).

As shown in FIG. 1, the convex part 61 which protrudes upward is formed in the edge of the both ends of the longitudinal direction of the dielectric member 60, respectively. The convex portion 61 extends along the longitudinal edge of the dielectric member 60. Both ends of the longitudinal direction of the bottom plate part 51 of the said electric field application side dielectric member 50 are mounted in these convex parts 61.

A narrow lower gap 1b is formed between the bottom plate portion 51 of the 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 the discharge space 1p. The upper surface of the ground side dielectric member 60 faces the field application side dielectric member 50, and further, the field application electrode 30. The upper surface of the ground-side dielectric member 60 is a partition formation surface for partitioning the discharge space 1p. As shown in FIG. 2, the both ends of the short direction of the lower clearance gap 1b continue in the lower end part of the side clearance gap 1c, respectively.

The ejection structure of the processing head 1 is demonstrated.

A plurality of blowout coatings 62 are formed in the ground-side dielectric member 60. The jet coating 62 penetrates in the thickness direction from the upper surface of the dielectric member 60 (the partitioning surface of the discharge space 1p) to the lower surface (surface covered by the ground electrode 40). The spray coating 62 is continuous in the discharge space 1p. The size and shape of the spray coating 62 is constant in the penetrating direction (up and down direction). For example, the spray coating 62 has a circular cross section of a constant size of about 1 mm in diameter.

The ground electrode 40 is provided with a plurality of jet holes 41. The jet port 41 penetrates from the upper surface (discharge surface 42) of the ground electrode 40 to the lower surface (processing surface 43) in the thickness direction. The size and shape of the jet port 41 are constant in the penetrating direction (up and down direction). For example, the jet port 41 has a circular cross section of a constant size of about 3 mm in diameter. The jet port 41 is arranged in one-to-one correspondence with the jet coating 62 of the ground-side dielectric member 60, and is continuous to the corresponding jet coating 62, respectively, and is continuous to the processing space 1a.

The jet port 41 and the jet coating 62 are regularly arranged. For example, as shown in Fig. 6A, the jet port 41 and the jet coating 62 may be arranged in a square grid shape. Alternatively, as shown in Fig. 6B, the jet port 41 and the jet coating 62 may be arranged in a triangular grid or the like.

As shown in an enlarged view in FIG. 4A, each jet port 41 is larger than the jet coating 62. The inner surface of the jetting coating 62 protrudes inward in the radial direction of the jetting opening 41 than the inner surface of the jetting opening 41. The lower surface of the dielectric member 60 includes a contact surface 63 and a stepped surface 64. The contact surface 63 is a portion of the lower surface of the dielectric member 60 that contacts and contacts the discharge surface 42 of the ground electrode 40. The step surface 64 constitutes the same plane as the contact surface 63, and extends from the contact surface 63 to the same surface inward in the radial direction of the jet port 41. The stepped surface 64 forms a step between the inner surface of the spray coating 62 and the inner surface of the spray port 41. The stepped surface 64 has an annular shape along the periphery of the jet port 41 and the jet coating 62. As shown in FIG. 4 (b), when viewed from the upper side (side of the electric field applying electrode 30), the peripheral portion of the jet coating 62 of the dielectric member 60 is formed of the jet opening 41 of the ground electrode 40. The upper edge 41a (the edge of the edge on the discharge face 42 side) is covered over the entire circumference.

The diameter of the jet port 41 is preferably about 0.5 to 4 mm larger than the diameter of the jet coating 62, and more preferably about 2 mm larger.

The width w1 (protrusion amount from the end edge of the jet port 41) of the step surface 64 is about w1 = 1 mm. The width w1 of the step surface 64 is larger than the allowable amount d1 (<1 mm) of the positioning error of the dielectric member 60 (w1> d1).

The assembling procedure of the treatment 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 housed inside the frame 20. The dielectric member 60 is placed on the upper surface 42 of the ground electrode 40. As a result, the ejection coating 62 of the dielectric member 60 and the ejection opening 41 of the ground electrode 40 communicate with each other. The inner surface of the spray coating 62 protrudes inward from the inner surface of the spray opening 41, and a step 64 is formed between the inner surface of the spray coating 62 and the inner surfaces of the spray opening 41. A clearance is set between the dielectric member 60 and the frame 20, so that the dielectric member 60 can be easily accommodated. Since this clearance is very small (d1 <1 mm), the dielectric member 60 can be positioned almost accurately with respect to the ground electrode 40. As shown in Fig. 5 (a), even if there is a positioning error of the dielectric member 60, the allowable amount d1 of the error is smaller than the width w1 (Fig. 4 (a)) of the stepped surface 64 in the normal positioning state. Therefore, the entire circumference of the inner surface of the ejection coating 62 necessarily protrudes inwardly from the inner surface of the ejection opening 41 (d1 <w1). Therefore, as shown in FIG. 5 (b), the entire circumference of the upper edge 41a of the jet port 41 as seen from the upper side is necessarily covered with the peripheral edge of the jet coating 62 of the dielectric member 60.

In addition, the electric field application side dielectric member 50 is inserted into the frame 20. Both ends of the longitudinal direction of this electric field application side dielectric member 50 are mounted on the convex part 61. The field application electrode 30 is placed on the bottom plate portion 51 of the 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 joint between the end piece 35 and the field application side dielectric member 50 is completely caulked with an adhesive or the like.

Subsequently, the top cover member 10 is covered over the members 20, 30, 50, the frame 20 is fixed to the top cover member 10 with a short bolt 91, and the ground electrode ( 40 is fixed to the frame 20, and the electric field applying side dielectric member 50 is fixed to the upper cover member 10 with a bolt 93 of a medium length. Since these bolts 91, 92, and 93 are all oriented in the same direction (vertical), there is no need to tighten them in parallel, and bolts can be easily tightened in any order.

When surface treatment is performed in the plasma processing apparatus having the above-described configuration, the workpiece W is set on the workpiece placement unit 2.

Then, the processing gas from the processing gas source 4 is supplied to the gas introduction passage 20a of the processing head 1 via the gas supply passage 4a. This processing gas is uniformly introduced into the side gap 1c from the plurality of gas inlets 20b and is also introduced into the lower gap 1b.

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

The plasma-processed processing gas is blown out from the blowing port 41 to the processing space 1a of the lower side via the blowing coating 62, and it contacts the to-be-processed object W. FIG. Thereby, reaction occurs on the surface of the to-be-processed object W, and desired surface treatment is performed. Moreover, the whole to-be-processed object W can be processed by scanning the to-be-processed object placement part 2 from side to side.

Since the inner surface of the spray coating 62 of the ground-side dielectric member 60 protrudes inwardly than the inner surface of the spray port 41 of the ground electrode 40, the dielectric member 60 is viewed from the field application electrode 30 side. ), The periphery of the spray coating 62 covers the inner surface of the spray opening 41. For this reason, abnormal discharge, such as an arc, can be prevented from generate | occur | producing in especially the upper-edge edge 41a of the inner surface of the blower outlet 41. FIG. As shown in FIG. 5, even if there is a positioning error of the dielectric member 60, the entire circumference of the upper edge 41a of the jet port 41 can be covered with the dielectric member 60. Therefore, abnormal discharge can be reliably prevented. Thereby, generation | occurrence | production of metal contamination and particle | grains can be prevented, and these metal contamination or particle | grains can be prevented from adhering to the to-be-processed object W. FIG.

Next, another embodiment of the present invention will be described. In the following embodiment, about the structure already mentioned above, the same code | symbol is attached | subjected to drawing, and description is abbreviate | omitted suitably.

7 shows a modification of the shape of the jet port 41. As shown in the figure (a), in this modification, the inner diameter of the upper edge 41a of the blower outlet 41 in the ground electrode 40 becomes larger than the inner diameter of the blower coating 62, and the blower outlet 41 is lowered. It has a tapered shape whose diameter is reduced toward. Therefore, as the size of the jet port 41 approaches the lower surface (processing surface 43) of the ground electrode 40, it becomes small gradually. The inner diameter of the lower end edge 41b of the jet port 41 (the size of the end on the treatment surface 43 side) is smaller than the inner diameter of the upper end edge 41a (the size of the end on the discharge surface 42 side).

In addition, as shown in FIG.7 (b), the inner diameter of the lower end edge 41b of the spray port 41 is made the same as the inner diameter of the spray coating 62. As shown in FIG. That is, the magnitude | size and shape of the edge part 41b of the process surface side of the jet port 41 correspond substantially with the magnitude | size and shape of the jet coating 62. As shown in FIG.

As a result, abnormal discharge such as an arc can be prevented from occurring at the upper and lower end edges 41a and 41b of the inner surface of the ejection opening 41, and at the same time, the intervention of an external atmosphere into the ejection opening 41 can be prevented. have. Further, the processing gas that has been plasma-formed in the discharge space 1p gradually tightens when passing through the spray port 41 through the spray coating 62, so that the spray gas can be ejected from the spray port 41 with high force. As a result, processing efficiency can be improved.

As shown in FIG. 8, instead of making the ejection opening 41 into a taper hole, the part 44 of the upper side (discharge surface side) of the ejection opening 41 is made into large diameter, and the lower side (processing surface side) of the ejection opening 41 is shown. By making the part 45 of () a small diameter, the step 46 can be formed between the upper part 44 and the lower part 45, and the jet port 41 can be stepped. The upper portion 44 has a larger diameter than the spray coating 62. The lower portion 45 has a diameter substantially the same as that of the spray coating 62.

In the modification shown in FIG. 9, the covering member 70 (bush) is provided in the inner surface of the jet nozzle 41 similar to 1st Embodiment (FIGS. 1-5). The covering member 70 is comprised from the insulator separate from the ground side dielectric member 60. As shown in FIG. It is preferable that the insulator used as the coating member 70 is a material with high plasma resistance and heat resistance, for example, a fluorine resin, quartz, glass, etc. are preferable.

The covering member 70 has comprised the cylinder shape. The outer peripheral surface of the covering member 70 is in close contact with the inner surface of the jet port 41.

The thickness of the coating member 70 is equal to the width w1 of the step surface 64. Therefore, the inner peripheral surface of the coating member 70 is the same surface as the inner surface of the spray coating 62. The internal space of the covering member 70 in the jet port 41 is continuous with the jet coating 62. The processing gas plasma-formed in the discharge space 1p is ejected through the internal space of the coating member 70 via the spray coating 62.

According to this aspect, since the inner surface made of the metal of the jet port 41 of the ground electrode 40 is covered with the covering member 70, abnormal discharge can be prevented more reliably. Since the inner circumferential surface of the coating member 70 is flush with the inner surface of the spray coating 62, particles can be prevented from being generated from the upper edge of the inner circumferential surface of the covering member 70 or the like.

As shown in FIG. 10, the jet port 41 and the jet coating 62 can be provided only in the center part of the width direction of the ground electrode 40 and the dielectric member 60, respectively.

The cross-sectional shape of the jet port 41 is preferably a round shape in consideration of workability and the like, but is not limited thereto, and may be an elliptical shape, an oblong shape, a polygonal shape such as a square shape, or a slit shape.

In the embodiment shown in FIG. 11, the jet port 41 and the jet coating 62 have a long hole shape. The major diameters of the jet port 41 and the jet coating 62 face each other in the same direction (here, the longitudinal direction of the processing head 1). The major diameter of the jet port 41 is larger than the major diameter of the jet coating 62. The short diameter of the jet port 41 is larger than the short diameter of the jet coating 62. The entire inner space of the spray coating 62 is continuous to the spray opening 41. A stepped surface 64 is formed between the inner surface of the jet port 41 and the inner surface of the jet coating 62. The stepped surface 64 has an elongated annular shape along the periphery of the jet port 41 and the jet coating 62. A plurality of long hole ejection openings 41 and ejection coating 62 are arranged in a line in the longitudinal direction of the processing head 1. Although the rows of the jetting port 41 and the jetting ball 62 adjacent to the short direction of the processing head 1 are shifted in the long direction of the processing head 1, these rows are arranged in the long direction of the processing head 1. Can be gathered

In the embodiment shown in FIG. 12, the ejection opening 41 and the ejection coating 62 have a slit shape extending longer in the longer direction of the treatment head 1 than the long hole ejection opening 41 and the ejection coating 62 of FIG. 11. It is. The length of the slit-shaped jet port 41 is larger than the length of the slit-shaped jet coating 62. The width of the slit-shaped jet port 41 is larger than the width of the slit-shaped jet coating 62. The entire internal space of the slit-shaped spray coating 62 is continuous to the slit-shaped spray opening 41. A stepped surface 64 is formed between the inner surface of the slit-shaped spray port 41 and the inner surface of the slit-shaped spray coating 62. The stepped surface 64 has a long annular shape along the periphery of the slit-shaped jet port 41 and the jet coating 62.

Only one set of the slit-shaped jet port 41 and the jet coating 62 is arranged at the center of the processing head 1 in the short direction, but the slit-shaped jet port 41 and the jet coating 62 are the processing head. It may be arranged at intervals in the short direction of (1).

As shown in FIG. 13, the long hole type or the slit type ejection port 41 and the ejection coating 62 may extend in the short direction of the treatment head 1. In FIG. 13, the plurality of jet ports 41 and the jet coating 62 extend in the short direction of the treatment head 1, respectively, and are arranged at intervals in the longitudinal direction of the treatment head 1.

As shown in Fig. 14, the long hole or slit-shaped jet port 41 and the jet coating 62 may extend obliquely with respect to the long direction and the short direction of the treatment head 1. In FIG. 14, a plurality of inclined jetting ports 41 and jetting coatings 62 are arranged at intervals in the longitudinal direction of the treatment head 1.

The present invention is not limited to the above embodiment, and various modifications can be made within a range apparent to those skilled in the art.

For example, the cross-sectional shape of the spray coating 62 is preferably similar to the cross-sectional shape of the spray opening 41, but as long as the ground electrode 40 is not exposed inside the spray coating 62 in plan view, The jet coating 62 may have a shape different from the jet port 41.

Instead of using the frame 20 as the position regulating means of the dielectric member 60, a convex portion or the like is provided in the ground electrode 40 or the dielectric member 50, and the convex portion regulates the position of the dielectric member 60. It can also be used as a position regulating means, or a dedicated member for regulating the position of the dielectric member 60 in the processing head 1 can be assembled as the position regulating means.

A plurality of embodiments can be combined with each other. For example, the long-hole or slit-shaped spout 41 shown in Figs. 11 to 14 may be made narrower in width, as in the embodiment of Fig. 7. Steps may be formed on the inner surface of the long hole or slit jet port 41 as in the embodiment of FIG. 8. The long annular insulating coating member (see Fig. 9) may be inserted into the long hole-type or slit-shaped jet opening 41, and the entire circumference of the inner circumferential surface of the long annular coating member may be a long-shaped or slit-shaped jet. It may be the same surface as the inner peripheral surface of the coating 62.

The present invention is applicable to various surface treatments such as cleaning, surface modification (hydrophilization, water repellency, etc.), etching, and film formation. It is not limited to the plasma process in the vicinity of atmospheric pressure, but it is applicable also to the plasma process in vacuum.

This invention is applicable to the surface treatment in the manufacturing process of the glass substrate and semiconductor substrate for flat display, for example.

Claims (8)

An apparatus for performing plasma surface treatment by causing a processing gas to be plasma-discharged in a discharge space and contacting a workpiece disposed on an object to be disposed outside of the discharge space to perform a plasma surface treatment. An electric field applying electrode connected to a power supply, An electrically grounded ground electrode having a discharge surface facing the electric field application electrode and a processing surface facing the object placement portion; A dielectric member made of a solid dielectric in contact with the discharge surface of the ground electrode and partitioning the discharge space facing the field applying electrode. The dielectric member is provided with a spray coating continuous to the discharge space. The ground electrode is provided with a jet port which is continuous with the jet coating and penetrates from the discharge surface to the processing surface, An inner surface of the jetting coating in the dielectric member protrudes radially inward of the jetting port from an end edge of the discharge surface side of the inner surface of the jetting hole in the ground electrode; The dielectric member has a contact surface in contact with the discharge surface of the ground electrode and a step surface extending from the contact surface to the same surface to form a step between the inner surface of the spray coating and the inner surface of the spray port. Plasma processing device. The plasma processing apparatus of claim 1, wherein a size and a shape of the jet port are constant in a penetration direction of the jet port. The plasma processing apparatus according to claim 1, wherein a size at an end of the processing surface of the jet port is smaller than a size at an end of the discharge surface side. 4. The plasma processing apparatus of claim 3, wherein the size of the jet port is gently reduced as it approaches the processing surface. The plasma processing apparatus according to claim 3 or 4, wherein the size and shape at the end of the jetting port at the end of the processing surface side substantially coincide with the size and shape of the jetting coating. A position regulating means according to any one of claims 1 to 5, further comprising a position regulating means for positioning the dielectric member while allowing an error in a plane parallel to the discharge surface with respect to the ground electrode, And a width along the protruding direction of the stepped surface in a state where the dielectric member is positioned at a normal position is larger than an allowable amount of the error. The plasma processing apparatus according to claim 1, further comprising a coating member made of an insulator separate from the dielectric member and provided to cover an inner surface of the blowout port of the ground electrode. 8. The plasma processing apparatus of claim 7, wherein a thickness of the covering member is approximately equal to a width along the protruding direction of the stepped surface.

Images