JP2010192262A - Plasma surface treatment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure treatment efficiency of a plasma surface treatment device by surely turning a treatment gas into plasma. <P>SOLUTION: An electrode 31 and a magnet 41 are alternately arrayed. A blowout channel 65 is formed between the magnet 41 and the electrode 31. A treated object 9 is supported by a support portion 21. Guide holes 63 of guide portions 11, 13 are connected to the blowout channel 65. The treatment gas is guided in from the guide holes 63 to the blowout channel 65. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an apparatus for converting a processing gas into plasma and bringing it into contact with an object to be processed, and to surface-treat the object to be processed.

  In the plasma surface treatment apparatus described in Patent Document 1, a plurality of flat electrodes are arranged in parallel in a vacuum chamber, and a magnet is disposed on the back side between adjacent electrodes. Plasma is generated by supplying AC voltages having different phases to a plurality of electrodes. Plasma diffusion is suppressed by the magnetic force of the magnet to increase the plasma density. Gas for generating plasma is put in the vacuum chamber.

JP 2007-193996 A

  The above-mentioned Patent Document 1 does not show how the gas for generating plasma is specifically put into the vacuum chamber or how the gas flows in the vacuum chamber. When the diffusion of plasma is suppressed by magnetic force, it may be considered that plasma formation becomes insufficient depending on how the gas flows.

The present invention has been made to solve the above-mentioned problems, and is an apparatus for converting a processing gas into a plasma and bringing it into contact with an object to be processed in a processing chamber to surface-treat the object to be processed,
A plurality of electrodes provided in the processing chamber;
One more magnet than the electrodes;
Support means for supporting the object to be processed on a virtual plane in the processing chamber;
An introduction part having an introduction hole for introducing a processing gas into the processing chamber;
The electrodes and the magnets are alternately arranged in a parallel direction parallel to the virtual plane and spaced apart from each other in a facing direction perpendicular to the virtual plane with respect to the virtual plane,
Each magnet is polarized in the opposite direction, and the magnetic poles of adjacent magnets sandwiching one electrode are opposite to each other,
A blowing path is formed between adjacent electrodes and magnets, and the introduction hole is connected to the side of the blowing path opposite to the virtual plane side.
An electric field is applied between the plurality of electrodes, and a plasma discharge is generated. This plasma discharge can be collected around each electrode by the magnetic field of the magnet to increase the plasma density. The processing gas passes through a blowing path between the magnet and the electrode and is supplied to the object to be processed. Therefore, it is possible to ensure that the processing gas passes through the inside of the plasma discharge portion around the electrode. Therefore, the processing gas can be reliably turned into plasma and brought into contact with the object to be processed. Thereby, processing efficiency is securable.

It is preferable that the outer peripheral surface of the electrode on the virtual plane side (processing object side) is a semi-cylindrical convex curved surface whose axis is directed in a direction orthogonal to the parallel direction and the opposing direction.
Thereby, at least a part of the processing gas flows so as to wrap around the outer peripheral surface of the electrode on the workpiece side from the blowing path, and the inside of the plasma discharge portion formed around the outer peripheral surface of the electrode on the workpiece side. pass. Therefore, the processing gas can be converted into plasma more fully. As a result, the processing efficiency can be further increased.

More preferably, the outer peripheral surface of the electrode is a cylindrical surface whose axis is oriented in a direction orthogonal to the parallel direction and the opposing direction.
Thus, the processing gas can flow along the peripheral surface of the electrode, and the processing gas can be made more fully plasma by the plasma discharge formed around the electrode. As a result, the processing efficiency can be further increased. An electrode can be comprised with a circular tube etc., and material cost can be reduced.

The introduction part has a surface facing the processing chamber and the introduction hole is opened, and a communication path is formed between the surface and the electrode to communicate the introduction hole and the blowing path. It is preferable that the introduction hole is disposed so as to face a central portion in the width direction of the electrodes (the parallel direction) in the facing direction.
The processing gas is blown from the introduction hole to the central portion of the peripheral surface of the electrode opposite to the object to be processed, and is divided into both sides in the width direction. The separated processing gas flows from the communication path to the blow-out path along the peripheral surface on the opposite side of the electrode, and further flows to the peripheral surface on the workpiece side of the electrode. In this process, the processing gas can surely pass through the inside of the plasma discharge portion around the electrode, and the processing gas can be sufficiently converted into plasma. The processing gas joins from both sides around the peripheral surface of the electrode on the workpiece side, and flows toward the workpiece. Thereby, the processing gas can be reliably brought into contact with the object to be processed, and the processing efficiency can be sufficiently increased.

It is preferable that the electrode and the magnet have a long shape whose longitudinal direction is oriented in a direction perpendicular to the parallel direction and the facing direction. It is preferable that the introduction holes are formed so as to be dispersed or extend in the longitudinal direction of each electrode.
Thereby, the said blowing path becomes slit shape extended in the said longitudinal direction. The process gas is made uniform and ejected in the longitudinal direction of the slit-like blowing path. Thereby, the processing degree along the said longitudinal direction of a to-be-processed object can be made uniform.

It is preferable that the introduction portion has a plate shape and supports an end portion of the magnet opposite to the virtual plane side.
Thereby, an introducing | transducing part serves as the support means of a magnet. An end of the blowing path opposite to the object to be processed can be closed by the introduction part. Alternatively, the communication path can be partitioned by a magnet.

It is preferable to include a processing container that can seal the processing chamber and a pressure adjusting unit that maintains the internal pressure of the processing chamber at a pressure in a viscous flow region lower than atmospheric pressure.
Accordingly, the processing gas can be reliably flowed along the peripheral surface of the electrode due to the viscosity, and the processing gas can surely pass through the inside of the plasma discharge portion around the electrode. Therefore, the processing gas can be sufficiently converted to plasma, and the processing efficiency can be reliably increased.
Here, the pressure range of the viscous flow region is preferably 10 to 150 Pa, and more preferably 50 to 150 Pa.

  According to the present invention, the processing gas can surely pass through the inside of the plasma discharge portion around the electrode, and the processing gas can be reliably converted into plasma and brought into contact with the object to be processed. Thereby, processing efficiency is securable.

It is a front view which shows the plasma surface treatment apparatus which concerns on one Embodiment of this invention in a closed state. It is a front view which shows the said plasma surface treatment apparatus in an open state. It is a top view of the said plasma surface treatment apparatus. It is a top view of the upper cover of the processing container of the said plasma surface treatment apparatus which follows the IV-IV line of FIG. FIG. 5 is a bottom view of the upper structure of the processing container along the line VV in FIG. 2. It is a top view of the lower side structure of the said processing container in alignment with the VI-VI line of FIG. It is side surface sectional drawing of the said plasma surface treatment apparatus which follows the VII-VII line of FIG. It is side surface sectional drawing which expands and shows the inside of the said processing container. FIG. 7 is a front cross-sectional view of a part of the processing container along the line IX-IX in FIG. 6. FIG. 10 is a cross-sectional plan view of a part of the processing container along line XX in FIG. 9. It is a plane sectional view of a portion on the opposite side to the left and right of FIG. It is a side sectional view of the inside of a processing container, showing a modification of the magnet shape.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 6, the workpiece 9 of this embodiment is configured by a rectangular glass substrate, for example. Although illustration is omitted, a metal film such as copper is formed on the surface of the glass substrate 9. Furthermore, an insulating film such as a silicon oxide film or a resin film such as a resist may be formed on the surface of the glass substrate 9. The surface of the glass substrate 9 is processed by the plasma surface processing apparatus 1. The plasma surface treatment apparatus 1 simultaneously performs surface treatment on both surfaces of the glass substrate 9.

  As shown in FIG. 1, the plasma surface treatment apparatus 1 includes an opening / closing support mechanism 2 and a processing container 10 (apparatus main body) supported by the opening / closing support mechanism 2. As shown in FIGS. 1 and 3, the opening / closing support mechanism 2 includes four (three or more) vertical columns 2a and an elevating cylinder 2b. The four struts 2a are arranged away from each other in the front / rear and left / right directions. An elevating cylinder 2b is disposed in the middle part of these columns 2a.

  As shown in FIG. 1, the processing container 10 includes an upper lid 11 and a container body 12. A processing chamber 10 a is defined inside the processing container 10 by an upper lid 11 and a container body 12.

  As shown in FIG. 3, the upper lid 11 is configured by a rectangular metal plate. As shown in FIG. 2, the upper lid 11 is horizontally supported by the upper ends of the four columns 2a.

As shown in FIG. 1, the container body 12 includes a bottom plate 13 and a peripheral wall 14. The bottom plate 13 is composed of a rectangular metal plate. The bottom plate 13 faces the processing chamber 10a and defines the bottom surface (lower inner surface) of the processing chamber 10a. As shown in FIG.2 and FIG.6, the surrounding wall 14 is comprised with the cyclic | annular metal member. The peripheral wall 14 is installed on the periphery of the upper surface of the bottom plate 13 and is connected to the bottom plate 13. An outer peripheral surface of the processing chamber 10 a is defined by the inner wall of the peripheral wall 14. As shown in FIG. 1, an observation window 14 a is provided on the peripheral wall 14. The inside of the processing chamber 10a can be observed by looking into the observation window 14a from the outside. As shown in FIG. 6, an O-ring 15 (seal member) is provided on the upper end surface of the peripheral wall 14. The O-ring 15 is disposed along the inner peripheral edge of the peripheral wall 14.
The O-ring 15 may be provided on the lower surface of the upper lid 11 instead of being provided on the upper end surface of the peripheral wall 14. As the seal member 15, a flat packing may be used instead of the O-ring.

  As shown in FIG.1 and FIG.2, the container main body 12 is supported by the support | pillar 2a so that a horizontal and vertical movement is possible. An elevating cylinder 2 b is connected to the center of the bottom surface of the container body 12. The container body 12 is moved up and down between the closed position (FIG. 1) and the open position (FIG. 2) by the lifting cylinder 2b.

  As shown in FIG. 1, when the container body 12 is in the closed position, the upper end surface of the peripheral wall 14 hits the lower surface of the upper lid 11. Thereby, the inside of the container main body 12 is closed by the upper lid 11, and the processing container 10 is closed. The bottom surface of the upper lid 11 faces the processing chamber 10a and defines the upper inner surface of the processing chamber 10a. The space between the upper lid 11 and the peripheral wall 14 is sealed by the O-ring 15. Thereby, the processing chamber 10a becomes a sealed space.

As shown in FIG. 2, the container body 12 in the open position is separated below the upper lid 11. Thereby, the upper surface of the processing chamber 10a is opened, and the processing container 10 is opened.
In the processing container 10, the position of the upper lid 11 is fixed, and the container main body 12 is opened and closed by moving up and down, but instead, the container main body 12 is fixed in position and the upper lid 11 is The processing container 10 may be opened and closed by moving up and down. The processing chamber 10a may be an integral box, and the side wall of the box may be opened and closed up and down like a shutter.

  As shown in FIGS. 2 and 6, the workpiece 9 is disposed in the processing chamber 10a. Inside the container main body 12, a support means 20 for the workpiece 9 is provided. The support means 20 includes a workpiece support part 21 and four (plural) insulation holding parts 22. The support portion 21 has a flat frame shape. The support part 21 is comprised, for example with metals, such as aluminum and stainless steel. As a material of the support portion 21, an insulator such as resin or ceramic may be used instead of metal.

  The insulating holding portions 22 are arranged at four locations on the front, rear, left and right in the processing chamber 10a. Each insulating holding portion 22 is fixed to the upper surface of the bottom plate 13. The insulation holding part 22 is comprised with insulators, such as a ceramic and resin. These insulating holding portions 22 hold the support portion 21 horizontally so as to be slidable in the front-rear direction (up and down in FIG. 6). As shown in FIG. 7, the support part 21 is arrange | positioned on the virtual plane PL of the height which bisects the process chamber 10a up and down.

  As shown in FIG. 9, a step-shaped latching portion 21 a is formed on the inner edge of the frame-shaped support portion 21. The outer peripheral portion of the workpiece 9 is hooked on the hook portion 21a. Thereby, the to-be-processed object 9 is supported in the state which was horizontal and both surfaces were exposed. The workpiece 9 supported by the support portion 21 is located on the virtual plane PL. An area in the virtual plane PL where the object 9 is disposed is a “processing area”.

  As shown in FIG. 6, a reciprocating mechanism 23 is provided behind the container body 12 (upper in FIG. 6). The reciprocating mechanism 23 is provided with a push / pull rod 24. The push-pull rod 24 extends straight in the front-rear direction (vertical direction in FIG. 6), and is advanced and retracted back and forth. The push-pull rod 24 penetrates the peripheral wall 14 and is inserted into the container body 12. A front end portion of the push-pull rod 24 is connected to the support portion 21 via a connecting member 25. By moving the push-pull rod 24 back and forth, the support portion 21 and the workpiece 9 are reciprocated back and forth.

  The connecting member 25 is made of an insulator such as resin. The connecting member 25 has such a size that creeping discharge is not transmitted between the support portion 21 and the push-pull rod 24. The support member 21 and the push / pull rod 24 are insulated by the connecting member 25.

  As shown in FIG. 7, a pressing tool 27 is placed on the upper surface of the support portion 21 and the upper surface of the outer peripheral portion of the workpiece 9. As shown by a two-dot chain line in FIG. 5, the presser 27 has a frame shape having the same shape and size as the support portion 21. The presser 27 is made of a metal such as aluminum or stainless steel, but may be made of an insulator such as resin or ceramic. The outer peripheral portion of the workpiece 9 is pressed from above by the presser 27, and the arrangement position is corrected.

  As shown in FIG. 7, an inverted L-shaped hook portion 27 a is provided on the outer peripheral portion of the presser 27. An L-shaped locking portion 26 is provided on the bottom surface of the upper lid 11 so as to hang down. As shown in FIG. 2, when the processing container 10 is in the open state, the hook portion 27 a is hooked on the locking portion 26. As a result, the presser 27 is supported so as to be hung away from the lower side of the upper lid 11.

As shown in FIG. 7, when the processing container 10 is in the closed state, the presser 27 is placed on the support portion 21 and the workpiece 9, and the hook portion 27 a is separated from the locking portion 26. At this time, the pressing tool 27 is not in contact with any member other than the support portion 21 and the workpiece 9. The support portion 21 is not in contact with any member other than the presser 27, the insulating holding portion 22, the insulating connecting member 25, and the workpiece 9. Therefore, the support part 21 and the pressing tool 27 are electrically floating. As a result, the workpiece 9 is in an electrically floating state (electrical float).
A column member may be provided on the bottom surface of the upper lid 11 and the pressing tool 27 may be fixed to the lower end of the column member. The column material is preferably made of an insulator such as ceramics. When the support part 21 moves back and forth during processing, a roller may be provided at the lower end of the column member, and the pressing tool 27 may be pressed by the roller.
The presser 27 may be omitted.

  As shown in FIG. 7, the processing container 10 is provided with a pair of upper and lower processing structure portions 10U and 10L. These processing structures 10U and 10L are vertically symmetric with respect to the horizontal plane on which the support 21 and thus the workpiece 9 is disposed.

  The upper and lower processing structures 10U and 10L are provided with an electrode group 30 and a magnet group 40, respectively. As shown in FIGS. 5 and 7, the electrode group 30 includes a plurality of electrodes 31. Each electrode 31 has a long cylindrical shape with its axis (longitudinal direction) directed to the left and right (first direction, left-right direction in FIG. 5, direction perpendicular to the plane of FIG. 7). Therefore, the outer peripheral surface of the electrode 31 is a cylindrical surface. In particular, the outer peripheral surface on the lower side (virtual plane PL side, that is, the workpiece side) of the electrode 31 of the upper structure portion 10U is a semi-cylindrical convex curved surface. The outer peripheral surface on the upper side (processing object side) of the electrode 31 of the lower structure portion 10L is a semi-cylindrical convex curved surface. The plurality of electrodes 31 of the electrode group 30 are arranged in parallel at intervals in the front-rear direction (parallel direction (vertical direction in FIG. 5, horizontal direction in FIG. 7)).

  The magnet group 40 includes a plurality of magnets 41. The number of magnets 41 is one more than the number of electrodes 31. Each magnet 41 is an elongated flat plate having a substantially rectangular cross section, the length direction is directed to the left and right (the left-right direction in FIG. 5, the direction orthogonal to the plane of FIG. 7), and the width direction is up and down (opposing direction (see FIG. 5 in the direction perpendicular to the plane of FIG. 5 (vertical direction in FIG. 7)), and the thickness direction is directed in the front-rear direction (parallel direction (vertical direction in FIG. 5, horizontal direction in FIG. 7)). Each magnet 41 may be a single body, or may be divided into a plurality of magnet pieces in the longitudinal direction, and these magnet pieces may be added in the longitudinal direction. As shown in FIG. 8, the magnet 41 is vertically polarized. The magnetic poles of two adjacent magnets 41 in the magnet group 40 are opposite to each other.

  The electrodes 31 and the magnets 41 are parallel to each other and are arranged alternately. Each electrode 31 is sandwiched between two magnets 41.

  As shown in FIG. 7, the workpiece 9 is arranged separately in the vertical direction (opposite direction) with respect to the upper and lower electrode groups 30 and the magnet group 40. The upper and lower electrode groups 30 and the magnet group 40 are arranged so as to sandwich the support portion 21 and the workpiece 9 from above and below.

The structure of the electrode group 30 and the magnet group 40 will be further described. Since the upper processing structure unit 10U and the lower processing structure unit 10L are vertically symmetrical, in the following description, the structure of the upper processing structure unit 10U will be described in detail, and the structure of the lower processing structure unit 10L will be described. Is simplified. First, the electrode support structure of the upper processing structure unit 10U will be described.
As shown in FIGS. 5 and 9, the electrode group 30 of the upper processing structure 10 </ b> U is attached to the upper lid 11. A pair of left and right electrode end support members 35, 35 are provided on the bottom surface of the upper lid 11. The electrode end support member 35 is detachably fixed to the upper lid 11 by screws 37 (fixing means). As shown in FIGS. 9 and 10, each electrode end support member 35 is a long cavity that opens into the upper surface and extends straight forward and backward (in the direction orthogonal to the plane of FIG. 9, the vertical direction in FIG. 10). It is box-shaped. The electrode end support member 35 is made of, for example, ceramic and has an insulating property. The electrode end support member 35 may be made of resin instead of ceramic. The electrode end support member 35 may be detachably attached to the upper lid 11 by other fixing means such as an elastic hook instead of the screw 37.

  As shown in FIGS. 9 to 11, a plurality of insertion holes 35 a are formed in the inner side walls (the walls on the side facing the electrode group 30) of the left and right electrode end support members 35. The insertion hole 35 a penetrates the inner wall of the electrode end support member 35 in the thickness direction, and the end on the back side communicates with the internal space of the electrode end support member 35. The plurality of insertion holes 35 a are arranged at intervals in the longitudinal direction of the electrode end support member 35 (the parallel direction of the electrodes 31). The insertion holes 35a and the electrodes 31 correspond one to one.

As shown in FIGS. 10 and 11, the outer circumferences of both end portions 31 a of the electrode 31 are reduced in diameter. An annular step 31b is formed between the outer peripheral surface of the end portion 31a of the electrode 31 and the outer peripheral surface on the inner side in the longitudinal direction from the end portion 31a.
The end 31 a of the electrode 31 may have the same outer diameter as the inner portion in the longitudinal direction from the end 31 a of the electrode 31.

  As shown in FIGS. 9 and 10, the left end 31 a of the corresponding electrode 31 is inserted into each insertion hole 35 a of the left electrode end supporting member 35. As shown in FIG. 11, the right end 31 a of the corresponding electrode 31 is inserted into each insertion hole 35 a of the right electrode end support member 35. The electrodes 31 are supported at both ends by the left and right electrode end support members 35. The left and right electrode end support members 35 connect the end portions 31a on the same side of the plurality of electrodes 31 to each other.

  A sufficient clearance is formed between the outer peripheral surface of the electrode end portion 31a and the inner peripheral surface of the insertion hole 35a. The distance between the left end step 31b (FIG. 10) and the right end step 31b (FIG. 11) of the electrode 31 is the distance between the right side of the left electrode end support member 35 and the left side of the right electrode end support member 35. For example, it is 1 to several mm smaller than the distance between them. As a result, the electrode 31 can be displaced in the longitudinal direction of the electrode 31 with both ends supported by the electrode end support members 35, 35.

  As shown in FIGS. 6 and 9, the electrode support structure of the lower processing structure portion 10L is the same as that of the upper processing structure portion 10U except that the electrode support structure is vertically inverted. In the lower processing structure portion 10 </ b> L, the electrode group 30 is attached to the bottom plate 13. A pair of left and right electrode end support members 35 are provided on the upper surface of the bottom plate 13, and the electrodes 31 are supported by these electrode end support members 35. The electrode end support member 35 of the lower processing structure portion 10L has a shape obtained by vertically inverting the electrode end support member 35 of the upper processing structure portion 10U.

A power feeding structure of the electrode group 30 will be described.
As shown in FIG. 3, the plasma surface treatment apparatus 1 includes a power source 3. The supply voltage of the power supply 3 may be an intermittent wave such as a pulse or a continuous wave such as an RF sine wave. A power supply line 3 extends from the power source 3 to the left side of the processing container 1.

A power feeding structure in the upper processing structure unit 10U will be described.
As shown in FIGS. 3 and 4, a power supply terminal 33 </ b> H is provided on the left side of the center of the upper plate 11. A plurality of power supply terminals 33H are arranged at intervals in the front and rear (up and down in FIG. 3). The feed line 3 is branched and connected to each feed terminal 33H. The left end portion of every other electrode 31 of the electrode group 30 is connected to the power supply terminal 33H, and thus connected to the power supply 3 via the power supply line 3h.

  As shown in FIGS. 3 and 4, a plurality of ground terminals 33 </ b> E are provided on the right side of the center of the upper lid 11. These ground terminals 33E are arranged at intervals in the front and rear (up and down in FIG. 3), and are shifted in the front and rear (up and down in FIG. 3) with respect to the power supply terminal 33H. The right ends of every other electrode 31 of the remaining electrode group 30 are connected to the ground terminal 33E, and thus are electrically grounded via a ground line 3e extending from the ground terminal 33E.

  Hereinafter, when the electrode 31 connected to the power source 3 and the grounded electrode 31 are distinguished from each other, the electrode 31 connected to the power source 3 is referred to as “hot electrode 31H”, and the grounded electrode 31 is referred to as “earth electrode”. 31E ". The hot electrodes 31H and the ground electrodes 31E are alternately arranged in the parallel direction (up and down in FIG. 5). A ground electrode 31 </ b> E is disposed on the outermost side of the electrode group 30.

  The connection position of the power supply terminal 33H in the hot electrode 31H and the connection position of the ground terminal 33E in the ground electrode 31E are arranged on opposite sides in the longitudinal direction of the electrode 31. That is, the power supply terminal 33H is connected to the left end portion of the electrode 31H. On the other hand, the ground terminal 33E is connected to the right end of the electrode 31E.

  As shown in FIG. 9, each terminal 33 includes a terminal main body 33 a and a spring 36. The terminal main body 33 a is pressed against the electrode 31 by the spring 36. Thereby, electrical communication between the terminal 33 and the electrode 31 is ensured. Even if the electrode 31 is extended by heat, electrical communication is ensured.

The power supply structure of the lower processing structure portion 10L is the same as that of the upper processing structure portion 10U except that the power supply structure is vertically inverted. Also in the electrode group 30 of the lower processing structure 10L, the hot electrodes 31H and the ground electrodes 31E are alternately arranged. As shown in FIG. 2, each terminal 33 of the lower processing structure 10 </ b> L is attached to the bottom plate 13.
In addition, as a terminal structure, it is not restricted above, Various structures are employable. For example, a terminal is provided on the outer side of the electrode end support member 35, and a thin metal plate or wire having elasticity is disposed along the surface of the electrode end support member 35 so that the electrode surface facing the processing space and the terminal are provided. You may connect with the said metal thin plate or a wire.

  As shown in FIGS. 7 and 8, the hot electrode 31H of the upper processing structure unit 10U and the hot electrode 31H of the lower processing structure unit 10L are vertically aligned in a one-to-one manner with the support unit 21 and the workpiece 9 interposed therebetween. The ground electrode 31E of the upper processing structure portion 10U and the ground electrode 31E of the lower processing structure portion 10L face each other straight and up and down.

As shown in FIG. 8, the outer peripheral surface on the upper side (opposite side of the workpiece) of each electrode 31 of the upper processing structure 10U is anodized to form an insulating film 32 made of an anodized film. . An insulating film 17 made of an alumite treatment film is formed on the lower surface of the upper lid 11. An insulating film 32 made of an alumite treatment film is formed on the outer peripheral surface of each electrode 31 of the lower processing structure portion 10L (on the side opposite to the object to be processed). An insulating film 17 made of an alumite treatment film is formed on the upper surface of the bottom plate 13.
The insulating film 32 of the electrode 31 is provided over the entire circumference of the outer peripheral surface of the electrode 31, but may be provided over a range less than or greater than a half circumference.
The insulating films 32 and 17 are not limited to the anodized film, and may be other insulating films such as a resin film.
The insulating film 32 may be omitted, and the entire metal portion of the outer peripheral surface of the electrode 31 may be exposed.

The plasma surface treatment apparatus 1 is provided with a temperature control (cooling) structure for each electrode 31.
Specifically, as shown in FIG. 3, a temperature adjustment medium introduction pipe 5 a extends from the temperature adjustment (cooling) medium source 5. As the temperature control medium (cooling medium) of the temperature control medium source 5, for example, fluoride water or water is used.

The upper electrode processing structure 10U incorporates the following electrode temperature control (cooling) structure.
As shown in FIGS. 3 and 4, in the upper processing structure unit 10 </ b> U, a temperature adjustment medium introduction port 51 is provided at one location (for example, the left rear side portion) of the upper lid 11. As shown in FIGS. 9 and 10, the temperature control medium introduction pipe 5 a is connected to the introduction port 51.

  The inner space of the left long box-like electrode end support member 35 is a temperature control medium introduction header path 52. The introduction header path 52 extends in the longitudinal direction of the electrode end support member 35 (the direction orthogonal to the plane of FIG. 9, the vertical direction in FIG. 10), and reaches the upper surface of the electrode end support member 35 and opens. The opening on the upper surface of the introduction header path 52 is closed by the upper lid 11. One end of the introduction header path 52 communicates with the introduction port 51.

  The internal space of each cylindrical electrode 31 is a temperature adjustment path 53 (cooling path). The temperature adjustment path 53 extends over the entire length in the longitudinal direction of the electrode 31 and reaches both end faces of the electrode 31. The left end portion (upstream end) of the temperature adjustment path 53 communicates with the side portion of the introduction header path 52.

  As shown in FIG. 11, the internal space of the right long box-like electrode end support member 35 is a temperature control medium outlet header path 54. The lead-out header path 54 extends in the longitudinal direction of the right electrode end support member 35 (up and down in FIG. 11). Although not shown in detail, the lead-out header path 54 reaches the upper surface of the right electrode end support member 35 (before the drawing in FIG. 11) and opens. The upper surface of the lead-out header path 54 is closed by the upper lid 11. The right end portion (downstream end) of the temperature adjustment path 53 of each electrode 31 communicates with the side portion of the lead-out header path 54.

  As shown in FIGS. 9 to 11, two (plural) O-rings 57 (electrode end seal members) are provided on the outer peripheral portion of the end 31 a of each electrode 31. The two O-rings 57 are arranged away from each other in the axial direction of the electrode end portion 31a (longitudinal direction of the electrode 31). The O-ring 57 seals between the inner peripheral surface of the insertion hole 35a and the outer peripheral surface of the electrode end portion 31a.

As shown in FIGS. 3 and 4, a temperature control medium outlet port 55 is provided at a position 180-degree rotationally symmetric with respect to the introduction port 51 of the upper lid 11. As shown in FIG. 11, the end of the derivation header path 54 is connected to the derivation port 55. The temperature control medium discharge pipe 5b is drawn out from the outlet port 55.
In addition, by providing a plurality of introduction ports 51 and outlet ports 55, the temperature adjustment medium may flow smoothly, and the temperature may be adjusted uniformly.

  As shown in FIGS. 2, 6, and 9, the electrode temperature adjustment structure of the lower processing structure portion 10 </ b> L is the same except that the electrode temperature adjustment structure of the upper processing structure portion 10 </ b> U is vertically inverted. ing. In the lower processing structure 10L, an introduction port 51 and a lead-out port 55 are provided on the bottom plate 13. Although illustration is omitted, the temperature control medium introduction pipe 5a is branched and connected to the introduction port 51 of the upper processing structure 10U and the introduction port 51 of the lower processing structure 10L.

Next, a support structure for the magnet group 40 will be described.
The magnet 41 of the upper processing structure 10U is connected to and supported by the upper lid 11 as follows.
As shown in FIG. 8, a magnet accommodation groove 42 is formed on the lower surface of the upper lid 11. The upper end of the magnet 41 (the end opposite to the object to be processed) is inserted into the accommodation groove 42. A pressing member 43 is pressed against one side of the upper end of the magnet 41. Thereby, the magnet 41 is pressed against the inner wall on the opposite side to the pressing member 43 side in the accommodation groove 42. A recess 45 for accommodating the pressing member 43 is formed on the upper surface of the upper lid 11. The pressing member 43 is fixed to the upper lid 11 with a set screw 44. The screw insertion hole 43b through which the set screw 44 of the pressing member 43 is passed is a long hole whose long axis is directed in the front-rear direction (left-right direction in FIG. 8). The pressing member 43 and the set screw 44 are arranged on the magnet 41, preferably on the ground electrode 31E side.
Although the magnets 41 are fixed to the lower surface of the upper lid 11 one by one, a structure in which a plurality of magnets 41 can be integrally attached and detached may be used.

  The support structure of the magnet 41 of the lower processing structure portion 10L is the same as that of the upper processing structure portion 10U except that it is inverted up and down. In the lower processing structure portion 10 </ b> L, the magnet 41 is attached to the upper surface of the bottom plate 13. A housing groove 42 and a recess 45 are formed on the upper surface of the bottom plate 13. The lower end portion of the magnet 41 is inserted into the accommodation groove 42.

  The magnet 41 of the upper processing structure unit 10U and the magnet 41 of the lower processing structure unit 10L are opposed to each other vertically in a one-to-one manner with the support unit 21 and the workpiece 9 interposed therebetween. The magnets 41 that are vertically opposed to each other have the same magnetic poles facing each other.

  As shown in FIG. 7, the plasma surface treatment apparatus 1 further includes a processing gas supply system 60 that supplies a processing gas to the object 9 to be processed in the processing chamber 10a. A processing gas source 6 is provided at the upstream end of the processing gas supply system 60. The processing gas source 6 sends out a processing gas containing components according to the processing purpose. For example, in the case of cleaning, ashing, or surface modification, oxygen is used as a processing gas.

  The processing gas supply system 60 of the plasma surface treatment apparatus 1 has two systems (a plurality of systems). Of the two processing gas supply systems 60, the first processing gas supply system 60A supplies the processing gas to the central portion (relatively inner portion) of the object 9 to be processed. The second processing gas supply system 60B supplies the processing gas to the outer peripheral portion of the workpiece 9 (the portion surrounding the inner portion). Details will be described below.

  The first processing gas supply system 60A includes a first supply path 6a extending from the processing gas source 6, and a first flow rate adjusting means 6va provided in the first supply path 6a. The second process gas supply system 60B includes a second supply path 6b extending from the process gas source 6 common to the first process gas supply system 60A, and second flow rate adjusting means 6vb provided in the second supply path 6b. have. Although detailed illustration is omitted, the first supply system 6a is bifurcated and extends to the upper processing structure 10U and the lower processing structure 10L of the processing vessel 10. Similarly, the second supply system 6b is bifurcated and extends to the upper processing structure 10U and the lower processing structure 10L of the processing container 10. The flow rate adjusting means 6va and 6vb are constituted by a mass flow controller or a flow rate control valve. The two flow rate adjusting means 6va and 6vb are operated in association with each other so that the supply flow rate of the first process gas supply system 60A is larger than the supply flow rate of the second process gas supply system 60B, for example.

A processing gas supply structure of the upper processing structure unit 10U will be described.
As shown in FIGS. 1 and 3, in the upper processing structure 10 </ b> U, a rectangular diffusion chamber defining plate 16 is provided in the center of the upper surface of the upper lid 11 in plan view. The diffusion chamber defining plate 16 covers the entire electrode group 30 in plan view. A plurality of process gas introduction ports 61 are provided on the upper surface of the diffusion chamber defining plate 16. These gas introduction ports 61 are classified into a plurality (for example, four) first gas introduction ports 61A and a plurality (for example, eight) second gas introduction ports 61B. The first gas introduction ports 61A are arranged in a distributed manner in the central portion (relatively inside) of the diffusion chamber defining plate 16. The first gas introduction port 61A is connected to the first supply path 6a and is an element of the first processing gas supply system 60A. The second gas introduction ports 61 </ b> B are distributed and arranged on the outer peripheral portion (relatively outside) of the diffusion chamber defining plate 16. The second gas introduction port 61B is connected to the second supply path 6b and is an element of the second processing gas supply system 60B.

  As shown in FIG. 7, a diffusion chamber 62 is defined between the diffusion chamber defining plate 16 and the upper lid 11 of the upper processing structure 10 </ b> U. The upper lid 11 is a partition that partitions the processing chamber 10 a and the diffusion chamber 62. The diffusion chamber 62 is a quadrangle having a spread that overlaps with the object 9 to be processed, that is, the entire processing area as viewed in a plan view, that is, when viewed from a direction orthogonal to the planar processing area in which the object 9 is disposed. ing. The gas introduction ports 61A and 61B are connected to the diffusion chamber 62. The central portion of the diffusion chamber 62 is an element of the first processing gas supply system 60A. The outer peripheral portion of the diffusion chamber 62 is an element of the second processing gas supply system 60B. The central portion and the outer peripheral portion of the diffusion chamber 62 are directly connected. An annular partition member that separates the central portion and the outer peripheral portion of the diffusion chamber 62 may be provided inside the diffusion chamber 62.

As shown in FIGS. 9 and 10, a large number (plural) of small processing gas introduction holes 63 are formed in the upper lid 11. The introduction holes 63 are arranged in a distributed manner in the surface of the upper lid 11. The introduction hole 63 penetrates from the upper surface to the lower surface of the upper lid 11. The diffusion chamber 62 and the processing chamber 10 a are connected by the introduction hole 63. As shown in FIG. 4, the introduction hole 63 is disposed at a position that overlaps each electrode 31 in plan view. In addition, the introduction hole 63 is disposed immediately above the upper end portion (the central portion in the width direction) of each electrode 31 and faces the upper end portion of the electrode 31 in the vertical direction (opposing direction). Furthermore, the introduction holes 63 are arranged at intervals in the longitudinal direction of the electrodes 31. The introduction hole 63 near the center of the upper lid 11 is an element of the first processing gas supply system 60A. The introduction hole 63 near the outer periphery of the upper lid 11 is an element of the second processing gas supply system 60B.
The introduction hole 63 may be formed in a slit shape extending in parallel with the longitudinal direction of the electrode 31 instead of a large number of small holes.

As shown in FIG. 8, a communication path 64 is formed between the electrode 31 of the upper processing structure 10 </ b> U and the upper lid 11. The communication path 64 extends in the longitudinal direction of the electrode 31. An end portion in the width direction of the communication path 64 is partitioned by the magnet 41. Each introduction hole 63 is connected to the communication path 64.

A blowing path 65 is formed between the electrode 31 and the magnet 41 adjacent to each other in the upper processing structure 10U. The blowout path 65 extends in the longitudinal direction of the electrode 31 and the magnet 41. The surface defined by the electrode 31 of the blowout path 65 is a semi-cylindrical concave curved surface. The surface defined by the magnet 41 of the blowout path 65 is flat. The upper part of the blow-out path 65 is connected to the communication path 64. A lower end portion of the blowout path 65 is connected to a processing space between the electrode group 30 and the magnet group 40 and the workpiece 9.
The upper lid 11 having the introduction hole 63 constitutes an introduction part that introduces the processing gas from the upper side of the electrode group 30 and the magnet group 40 (the side opposite to the object to be processed) into the blowing path 65.

  The processing gas supply structure of the lower processing structure unit 10L is the same as that of the upper processing structure unit 10U except that the processing gas supply structure is inverted up and down. In the lower processing structure portion 10L, a diffusion chamber defining plate 16 is provided on the lower surface of the bottom plate 13. A first gas introduction port 61 </ b> A is provided at the center of the diffusion chamber defining plate 16, and a second gas introduction port 61 </ b> B is provided at the peripheral portion of the diffusion chamber defining plate 16. The first supply path 6a from the processing gas source 6 is branched and connected to the first gas introduction port 61A of the upper processing structure 10U and the first gas introduction port 61A of the lower processing structure 10L. Further, the second supply path 6b is branched and connected to the second gas introduction port 61B of the upper processing structure unit 10U and the second gas introduction port 61B of the lower processing structure unit 10L. In the lower processing structure 10 </ b> L, a diffusion chamber 62 is formed between the diffusion chamber defining plate 16 and the bottom plate 13. An introduction hole 63 is formed in the bottom plate 13. A communication path 64 is formed between the bottom plate 13 and the electrode 31. The bottom plate 13 having the introduction hole 63 constitutes an introduction portion that introduces the processing gas from the lower side of the electrode group 30 and the magnet group 40 (the side opposite to the object to be processed) to the blowing path 65.

Furthermore, as shown in FIG. 7, the plasma surface treatment apparatus 1 is provided with an exhaust system 70 for exhausting gas from the inside of the processing chamber 10a. The exhaust system 70 is configured as follows.
As shown in FIGS. 4 and 5, in the upper processing structure 10 </ b> U, the upper lid 11 is formed with a plurality of exhaust holes 71. Each exhaust hole 71 penetrates the upper lid 11 in the thickness direction (up and down). The plurality of exhaust holes 71 are formed in the processing chamber 10a so as to surround the electrode group 30 and the magnet group 40 with respect to each other in plan view (viewed from a direction orthogonal to the virtual plane PL), and thus to surround the object 9 to be processed. It is distributed in an annular shape along the outer periphery. Further, almost all of the exhaust holes 71 are disposed outside the support portion 21 in a plan view.

  As shown in FIGS. 1 and 3, four (plural) exhaust cylinders 72 are provided on the upper surface of the upper lid 11. As shown in FIG. 3 and FIG. 7, each exhaust cylinder 72 has a container shape that is curved in an arc shape in a plan view and has an open bottom. The opening at the bottom of the exhaust cylinder 72 is closed by the upper lid 11. The four exhaust cylinders 72 are arranged to be separated from each other on the front, rear, left and right four sides of the upper surface of the upper lid 11 so as to be annular as a whole. A plurality of front exhaust holes 71 are connected to the internal space of the exhaust cylinder 72 on the front side (lower side in FIG. 3). A plurality of rear exhaust holes 71 are connected to the internal space of the exhaust cylinder 72 on the rear side (upper side in FIG. 3). A plurality of left exhaust holes 71 are connected to the internal space of the left exhaust cylinder 72. A plurality of right exhaust holes 71 are connected to the internal space of the right exhaust cylinder 72.

  An exhaust pipe 73 extends from each exhaust cylinder 72. The exhaust means 7 is connected to the exhaust pipe 73. The exhaust means 7 includes a vacuum pump and a detoxification facility.

As shown in FIGS. 6 to 9, the exhaust structure of the lower processing structure portion 10L is the same as that of the upper processing structure portion 10U except that the exhaust structure is inverted up and down. An exhaust hole 71 is formed in the bottom plate 13 in the lower processing structure 10L. An exhaust cylinder 72 is provided on the lower surface of the bottom plate 13. The exhaust holes 71 of the upper processing structure portion 10U and the exhaust holes 71 of the lower processing structure portion 10L are disposed on both upper and lower sides with a virtual plane PL having a height at which the workpiece 9 is disposed. Moreover, the exhaust holes 71 of the upper processing structure portion 10U and the exhaust holes 71 of the lower processing structure portion 10L face each other one-on-one and overlap each other in a plan view (in a direction orthogonal to the virtual plane PL). .
Instead of making the exhaust structure vertically symmetrical, the exhaust structure may be provided only in one of the upper or lower structure portions 10U, 10L. An exhaust hole may be provided in the side wall of the processing vessel 10 and the air may be exhausted therefrom.
In order to make the exhaust pressure constant, a throttle may be provided on the upstream side of the exhaust hole 71, for example, between the exhaust hole 71 and the workpiece support 21.

A method for surface-treating the workpiece 9 by the plasma surface treatment apparatus 1 configured as described above will be described.
As shown in FIG. 2, the processing container 10 is opened. Next, the workpiece 9 is put into the processing chamber 10 a with a manipulator, and the outer peripheral portion of the workpiece 9 is locked to the locking portion 21 a of the support portion 21. Thereby, the workpiece 9 is supported by the support portion 21. The upper and lower surfaces of the workpiece 9 are exposed in the supported state.

  Next, as shown in FIG. 1, the processing container 10 is closed, and the processing space 10a is sealed. The O-ring 15 can ensure a seal between the upper lid 11 and the container body 12. Since the processing body 10 is opened and closed by the parallel movement of the container body 12 up and down, the wear of the O-ring 15 can be suppressed.

  As shown in FIG. 9, when the processing container 10 is closed, the presser 27 is placed on the outer peripheral portion of the workpiece 9. With this presser 27, the outer peripheral part of the workpiece 9 can be pressed from above. When the arrangement position of the workpiece 9 is shifted, the position of the workpiece 9 can be corrected by the weight of the presser 27. Even if the workpiece 9 is warped, the warp can be corrected by the presser 27. The outer peripheral portion of the workpiece 9 is sandwiched from above and below by the presser 27 and the locking portion 21a, and can be firmly held.

  Further, as shown in FIG. 7, the hook portion 27 a of the presser 27 is separated from the locking portion 26. Thereby, the pressing part 27 is in an electrically floating state. Further, the support portion 21 is insulated from the processing container 10 by the insulating holding portion 22 and is electrically floating. Therefore, the workpiece 9 can be floated electrically.

Drives the pressure adjusting step evacuation means 7 (pressure adjusting means), it sucks the gas in the processing chamber 10a, the pressure in the processing chamber 10a lower than the atmospheric pressure. The pressure in the processing chamber 10a is preferably a viscous flow region (weak vacuum) of 10 to 150 Pa, more preferably 50 to 150 Pa.

A voltage is supplied from the plasma generation process power supply 3 to the upper and lower electrodes 31H. Thereby, as shown in FIG. 8, in the upper processing structure 10U, an electric field is applied between the adjacent electrodes 31H and 31E, and a plasma discharge 39 is generated. The plasma discharge 39 is generated from a portion where the metal of each electrode 31 is exposed. In the upper processing structure 10U, the exposed metal portion of the electrode 31 is directed to the lower side, that is, the workpiece 9 side. Since the anodized film 32 is formed on the outer peripheral surface on the upper side of the electrode 31, that is, on the side opposite to the object to be processed, it is possible to prevent plasma discharge from occurring on the opposite side. Furthermore, the alumite treatment films 32 and 17 can prevent plasma discharge from being formed between the hot electrode 31H and the upper lid 11.

  In the upper processing structure 10 </ b> U, a magnetic field 49 is formed between the lower (end of the object to be processed) ends of two magnets 41 that are adjacent to each other with the electrode 31 interposed therebetween. The magnetic field 49 can prevent the plasma discharge 39 from diffusing, and the plasma discharge 39 can be collected around the outer peripheral surface of each electrode 31 on the lower side (processing object side). Thereby, the density of the plasma discharge 39 can be increased.

  Similarly, in the lower processing structure portion 10L, a plasma discharge 39 is generated from the exposed metal portion on the upper side (the object to be processed) of each electrode 31. Further, a magnetic field 49 is formed between the upper end portions (the workpiece side) of two magnets 41 adjacent to each other with the electrode 31 interposed therebetween. The diffusion of the plasma discharge 39 can be suppressed by the magnetic field 49, and the plasma discharge 39 can be collected around the outer peripheral surface on the upper side (object side) of each electrode 31 to increase the density of the plasma discharge 39. Further, the alumite treatment films 32 and 17 can prevent plasma discharge from being formed between the hot electrode 31H and the bottom plate 13.

  The support part 21 and the pressing tool 27 are in an electrically floating state, and thus the workpiece 9 is in an electrically floating state. Therefore, it is possible to prevent the electrode 31H from dropping to the object 9 or discharging charged particles in the plasma in contact with the object to be processed. As a result, it is possible to reliably prevent the workpiece 9 from being damaged by the plasma.

  When the electrode 31 is heated by the above plasma generation, the electrode end 31a can be displaced in the longitudinal direction of the electrode 31 in the insertion hole 35a. Therefore, thermal expansion of the electrode 31 is allowed and the thermal stress of the electrode 31 can be released. As a result, it is possible to prevent the electrode 31 from being bent and the electrode end support member 35 from being damaged.

Electrode Cooling (Temperature Control) Step Further, the cooling medium of the cooling (temperature control) medium source 5 is sent to the introduction pipe 5a. In the upper processing structure 10 </ b> U, the cooling medium is introduced into both longitudinal ends of the introduction header path 52 through the introduction ports 51 before and after the upper lid 11, and flows toward the longitudinal center of the introduction header path 52. , And distributed to each temperature control path 53. The cooling medium flows in each temperature control path 53 from the left side (introduction header path 52 side) to the right side (outflow header path 54 side). The electrode 31 can be cooled (temperature controlled) by the cooling medium flowing through the temperature control path 53. Thereby, the thermal expansion of the electrode 31 can be suppressed. As a result, it is possible to more reliably prevent the electrode 31 from being bent and the electrode end support member 35 from being damaged.
Thereafter, the cooling medium is collected in the lead-out header path 54 and is discharged from the lead-out port 55 to the discharge pipe 5b and discharged.
The O-ring 57 can prevent the cooling medium from leaking out from the gap between the inner peripheral surface of the insertion hole 35a of the electrode end support member 35 and the outer peripheral surface of the electrode end portion 31a.

Process gas supply process The process gas is sent from the process gas source 6 to the supply path 6a of the first process gas supply system 60A and the supply path of the second process gas supply system 60B. The processing gas is introduced into the diffusion chamber 62 through the introduction port 61 of each processing structure 10U, 10L, and diffuses throughout the diffusion chamber 62. In this diffusion chamber 62, the processing gases of the two processing gas supply systems 60A and 60B are partially mixed. Next, the processing gas flows into the communication path 64 through each introduction hole 63.

  As shown by a thick arrow f in FIG. 8, in the upper processing structure 10 </ b> U, the processing gas that has entered the communication path 64 from the introduction hole 63 of the upper lid 11 is divided into both sides at the upper part of the electrode 31. The separated processing gas flows from the communication path 64 to the blowing path 65 so as to be along the upper outer peripheral surface of the electrode 31. The processing gas passes through the communication path 64 and the blowout path 65, and is made uniform in the longitudinal direction of the electrode 31 and the magnet 41 (direction perpendicular to the paper surface of FIG. 8). Further, the processing gas circulates along the lower outer peripheral surface of the electrode 31 having a circular cross section due to viscosity and enters the plasma discharge part 39, and substantially along the width direction (left-right direction) of the plasma discharge part 39. Flowing. As a result, the time or distance that the processing gas passes through the plasma discharge part 39 can be lengthened. Therefore, the processing gas can be sufficiently converted into plasma (including excitation, activation, radicalization, and ionization), and the concentration of active species can be sufficiently increased. This processing gas gradually flows downward from the plasma discharge portion 39 and comes into contact with the upper surface of the workpiece 9. Further, in the vicinity of the lower portion of the electrode 31 (the peripheral surface on the object to be processed), the processing gases from both sides merge and flow toward the object 9 to be processed. As a result, the processing gas can be reliably brought into contact with the workpiece 9, and the upper surface of the workpiece 9 can be surface-treated. Since the processing gas is made into high plasma, the processing efficiency can be sufficiently increased.

Similarly, in the lower processing structure portion 10 </ b> L, the processing gas that has entered the communication path 64 from the introduction hole 63 of the bottom plate 13 is divided into left and right portions below the electrode 31. The processing gas divided into right and left flows from the communication path 64 to the blowout path 65 along the lower outer peripheral surface of the electrode 31, and further flows into the upper outer peripheral surface of the electrode 31. Therefore, the time or distance that the processing gas passes through the plasma discharge 39 can be lengthened, and the processing gas can be sufficiently converted to plasma. The processing gas gradually flows upward from the plasma discharge 39 and comes into contact with the lower surface of the workpiece 9. Thereby, the lower surface of the workpiece 9 can be surface-treated with sufficient treatment efficiency.
By supplying the processing gas from the upper and lower sides to the processing object 9 with the processing object 9 (virtual plane PL) in between, both surfaces of the processing object 9 can be processed simultaneously.

  In the process gas supply process, the process gas supply flow rates of the two supply systems 60A and 60B are adjusted in association with each other by the flow rate adjusting means 6va and 6vb. For example, the flow rate of the supply path 6a of the first supply system 60A is relatively increased, and the flow rate of the supply path 6b of the second supply system 60B is relatively decreased. As a result, the processing gas flow rate in the central portion of the diffusion chamber 62 increases, and the processing gas flow rate in the introduction hole 63 communicating with the central portion of the diffusion chamber 62 increases. Further, the processing gas flow rate at the outer peripheral portion of the diffusion chamber 62 is reduced, and the processing gas flow rate of the introduction hole 63 communicating with the outer peripheral portion of the diffusion chamber 62 is reduced. Therefore, the flow rate of the processing gas sprayed onto the central region of the workpiece 9 is increased, and the flow rate of the processing gas sprayed onto the outer peripheral region of the workpiece 9 is decreased. Thereby, the processing gas can be flowed so as to be pushed out from the central region of the workpiece 9 to the outer peripheral region, and the processing gas can be prevented from staying in the central region of the workpiece 9. Assuming that the treated gas (the treated gas after contributing to the surface treatment) contains impurities such as reaction by-products, the treated gas can flow out smoothly from the workpiece 9 and the processing quality is good. Can be maintained.

  The central region of the workpiece 9 is sufficiently surface-treated with a large flow of processing gas. The processing gas blown to the central region of the workpiece 9 contributes to the surface treatment of the central region of the workpiece 9 and then flows along the upper surface of the workpiece 9 to the outer peripheral region of the workpiece 9. The outer peripheral area of the workpiece 9 is surface-treated by a processing gas flowing from the central area of the workpiece 9 in addition to being surface-treated by a small flow of processing gas blown directly onto the outer circumferential area. The As a result, the surface treatment amount of the central area and the outer peripheral area of the workpiece 9 can be made substantially the same.

One supply flow rate of the two processing gas supply systems 60A and 60B may be maintained constant, and the other supply flow rate may be periodically changed. The fluctuation period is, for example, several seconds to several tens of seconds.
Both of the two processing gas supply systems 60A and 60B may be periodically changed, the period of change may be shifted, and the processing gas supply by the first processing gas supply system 60A and the second processing gas supply system 60B may be shifted. The process gas supply may be alternately performed. The process gas supply period by the first process gas supply system 60A may be longer than the process gas supply period by the second process gas supply system 60B.
Depending on the processing, the processing gas supply amounts from the upper and lower processing structures 10U, 10L may be the same or different from each other.

Along with the swinging process , the support unit 21 is moved back and forth (swinged) by the reciprocating mechanism 23. Thereby, the to-be-processed object 9 reciprocates back and forth. The moving speed is preferably about 10 to 30 mm / sec, for example. The width of the reciprocating movement of the workpiece 9 is about half of the arrangement pitch of the electrodes 31. Thereby, each part of the to-be-processed object 9 can be made to contact a process gas equally mutually. As a result, the surface treatment of the workpiece 9 can be made uniform.

Exhaust process The exhaust means 7 (pressure adjuster) is driven continuously from the pressure adjusting process, and the pressure in the viscous flow region (preferably 10 to 150 Pa, more preferably, regardless of the supply of the processing gas to the internal pressure of the processing chamber 10a). 50-150 Pa). The treated gas flows to the outside of the workpiece 9 so as to diffuse in all directions around the workpiece 9 in plan view, and further flows to the outside of the support portion 21. As shown by the thick arrow fe in FIG. 7, the processed gas that has flowed into the processing chamber 10 a outside the support portion 21 is sucked into the upper and lower exhaust holes 71. The treated gas generated on the upper side of the workpiece 9 is mainly sucked into the upper exhaust hole 71. The treated gas generated below the workpiece 9 is mainly sucked into the lower exhaust hole 71. The processed gas in the processing chamber 10a can be sucked almost uniformly from the outer side of the object 9 to be processed in a plan view and from all directions around the object 9 to be processed. Thereby, it is possible to prevent gas vortex and gas accumulation in the processing chamber 10a.

Thereafter, the processed gases sucked from the plurality of exhaust holes 71 on the front side of the processing chamber 10a merge inside the front exhaust cylinder 72, and further, through the exhaust pipe 73 connected to the front exhaust cylinder 72, and exhaust means 7 is sent. Similarly, the processed gases sucked from the plurality of exhaust holes 71 on the left side of the processing chamber 10a merge inside the left exhaust cylinder 72 and pass through the exhaust pipe 73 connected to the left exhaust cylinder 72 to be exhausted. 7 is sent. Processed gases sucked from a plurality of exhaust holes 71 on the right side of the processing chamber 10 a merge inside the right exhaust cylinder 72 and are sent to the exhaust means 7 via an exhaust pipe 73 connected to the right exhaust cylinder 72. It is done. Processed gases sucked from the plurality of exhaust holes 71 on the rear side of the processing chamber 10 a merge inside the rear exhaust cylinder 72, pass through an exhaust pipe 73 connected to the rear exhaust cylinder 72, and exhaust means 7 is sent.
Depending on the processing, the processed gas exhaust amounts from the upper and lower processing structures 10U, 10L may be the same or different from each other.

When the surface treatment of the workpiece is taken out step treatment object 9 has been completed, and stops the voltage supply from the power source 3, and stops the processing gas supply from the processing gas source 6. Further, the gas suction by the exhaust means 7 is stopped, and the inside of the processing chamber 10a is returned to the atmospheric pressure. Next, the container body 12 is lowered by the elevating cylinder 2b to open the processing container 10. And the to-be-processed object 9 is taken out from the process chamber 10a with a manipulator.

  In the upper processing structure 10 </ b> U, all the electrodes 31 can be separated from the upper lid 11 by removing the screw 37 and removing the electrode end support member 35 from the upper lid 11. In the lower processing structure 10 </ b> L, all the electrodes 31 can be separated from the bottom plate 13 by removing the screw 37 and removing the electrode end support member 35 from the bottom plate 13. Each electrode 31 can be easily separated from the electrode end support member 35 by pulling out the end 31a from the insertion hole 35a. Thereby, maintenance such as replacement of the electrode 31 can be easily performed.

The present invention is not limited to the above-described embodiment, and can be appropriately modified within a range obvious to those skilled in the art.
For example, the surface treatment may be performed with the processing chamber 10a in an atmospheric pressure environment. The internal pressure of the processing chamber 10a may be lower than the viscous flow region (weak vacuum), for example, a strong vacuum of less than 1 Pa to several Pa.
The shape of the electrode 31 is not limited to a cylindrical shape with a perfect circular cross section, and may be a cylindrical shape with an elliptical cross section, and at least the outer peripheral surface on the workpiece side may be a cylindrical shape (a semi-cylindrical convex curved surface), The outer peripheral surface on the side opposite to the object to be processed may be flat. The electrode 31 may have a polygonal cross-sectional shape such as a quadrangle, or a deformed polygonal cross-sectional shape.
Instead of forming a plasma electric field by the combination of the high-voltage side electrode 31H and the ground electrode 31E, the plasma electric field is shifted between the two electrodes by shifting the phase of the power supply voltage to the at least two electrodes 31, 31 from each other. May be formed.
A plasma electric field may be formed between the electrode 31 of the upper processing structure 10U and the electrode 31 of the lower processing structure 10L.
The present invention may be applied to direct processing in which plasma processing is performed by placing the workpiece 9 inside the discharge space, or to remote processing in which plasma processing is performed by spraying plasma on the workpiece 9 disposed outside the discharge space. May be.

  The introduction hole 63 may be displaced from the central portion of the electrode 31 in the width direction. For example, the introduction hole 63 may be disposed at a position that communicates with the blowout path 65 in the vertical direction (opposite direction). The magnet 41 is separated from the introduction portions 11 and 13, the introduction hole 63 is disposed at a position facing the magnet 41 in the vertical direction (opposing direction), and a communication path 64 is formed between the magnet 41 and the introduction portions 11 and 13. May be.

The cross-sectional shape of the magnet 41 is not limited to a rectangle.
For example, the magnet 41 of the modification shown in FIG. 12 has a pentagonal cross-sectional shape in which the width of the end on the workpiece side (lower side in FIG. 12) decreases toward the tip, and the tip is sharp. . A magnetic field is formed between the sharp tips of adjacent magnets 41. According to this modification, the distance between the electrode 31 and the magnet 41 can be further reduced. Accordingly, the interval between the adjacent electrodes 31 can be reduced. As a result, the electric field strength between the electrodes 31 can be further increased, and good plasma can be obtained.

  The surface treatment is not limited to the simultaneous surface treatment of both surfaces of the workpiece 9, and only one surface of the workpiece 9 may be surface treated. In this case, one of the upper and lower processing structures 10U and 10L, the electrode group 30 and the magnet group 40, the processing gas supply structure, and the like may be omitted. The exhaust hole 71 may be disposed at the center of the processing chamber 10a opposite to the side where the electrode group 30 and the magnet group 40 are located with the workpiece 9 interposed therebetween. The support portion 21 may be in a stage shape.

The present invention can be applied to various surface treatments such as cleaning, surface modification, etching, film formation, and ashing.
The object to be processed is not limited to a glass substrate, but may be a semiconductor wafer, a metal plate, or a resin film. The surface of the object to be processed that is not desired to be processed may be covered with a cover means such as an object to be processed to process only one surface.

  The present invention is applicable to surface treatment of a glass substrate for flat panel display (FPD), for example.

DESCRIPTION OF SYMBOLS 1 Plasma surface treatment apparatus 2 Opening-closing support mechanism 2a Support | pillar 2b Elevating cylinder 10 Processing container 10a Processing chamber 10U Upper processing structure part 10L Lower processing structure part 11 Upper cover (introduction part, partition)
12 Container body 13 Bottom plate (introduction part, partition)
14 peripheral wall 14a observation window 15 O-ring (seal member)
16 Diffusion chamber defining plate 17 Anodized film (insulating film)
20 workpiece support means 21 workpiece support portion 21a latching portion 22 insulating holding portion 23 reciprocating mechanism 24 push / pull rod 25 connecting member 26 locking portion 27 pressing tool 27a hooking portion 30 electrode group 3 power supply 3h feed line 3e grounding Wire 31 Electrode 31H Hot electrode 31E Earth electrode 31a Electrode end 31b Step 32 Alumite coating (insulating film)
33 terminal 33H power supply terminal 33E ground terminal 35 electrode end support member 35a insertion hole 36 spring 37 electrode support member fixing screw 39 plasma discharge part 40 magnet group 41 magnet 42 magnet receiving groove 43 pressing member 43b screw insertion hole 44 set screw 45 Concave portion 49 Magnetic field 5 Temperature control (cooling) medium source 5a Temperature control (cooling) medium introduction pipe 5b Temperature control (cooling) medium discharge pipe (discharge path)
51 Temperature Control (Cooling) Medium Introduction Port 52 Temperature Control (Cooling) Medium Introduction Header Path 53 Temperature Control Path (Cooling Path)
54 Temperature control (cooling) medium outlet header path 55 Temperature control (cooling) medium outlet port 57 O-ring (electrode end seal member)
6 Process gas source 6a First supply path 6b Second supply path 6va First flow rate adjusting means 6vb Second flow rate adjusting means 60A First process gas supply system 60B Second process gas supply system 61 Process gas introduction port 61A First introduction port 61B Second introduction port 62 Diffusion chamber 63 Process gas introduction hole 64 Communication passage 65 Blowout passage 7 Exhaust means (process chamber pressure adjustment means)
70 Exhaust system 71 Exhaust hole 72 Exhaust cylinder 73 Exhaust pipe 9 Object PL Virtual plane

Claims (7)

An apparatus for converting a processing gas into plasma and bringing it into contact with an object to be processed in a processing chamber to surface-treat the object to be processed,
A plurality of electrodes provided in the processing chamber;
One more magnet than the electrodes;
Support means for supporting the object to be processed on a virtual plane in the processing chamber;
An introduction part having an introduction hole for introducing a processing gas into the processing chamber;
The electrodes and the magnets are alternately arranged in a parallel direction parallel to the virtual plane and spaced apart from each other in a facing direction perpendicular to the virtual plane with respect to the virtual plane,
Each magnet is polarized in the opposite direction, and the magnetic poles of adjacent magnets sandwiching one electrode are opposite to each other,
A plasma surface treatment apparatus, wherein a blowing path is formed between an adjacent electrode and a magnet, and the introduction hole is connected to a side opposite to the virtual plane side of the blowing path.   2. The plasma surface treatment apparatus according to claim 1, wherein an outer peripheral surface of the electrode on the virtual plane side is a semi-cylindrical convex curved surface whose axis is directed in a direction orthogonal to the parallel direction and the opposing direction. .   3. The plasma surface treatment apparatus according to claim 1, wherein the outer peripheral surface of the electrode is a cylindrical surface whose axis is oriented in a direction perpendicular to the parallel direction and the opposing direction.   The introduction portion has a surface facing the processing chamber and the introduction hole is open, and a communication path is formed between the surface and the electrode to communicate the introduction hole and the blowout path. The plasma surface treatment apparatus according to claim 3, wherein the introduction hole is disposed so as to face a central portion in the width direction of the electrode in the facing direction.   The electrodes and magnets have a long shape whose longitudinal direction is in a direction perpendicular to the parallel direction and the opposing direction, and the introduction holes are formed so as to be dispersed or extend in the longitudinal direction of each electrode. The plasma surface treatment apparatus according to claim 1, wherein the apparatus is a plasma surface treatment apparatus.   The plasma surface treatment according to claim 1, wherein the introduction portion has a plate shape and supports an end portion of the magnet opposite to the virtual plane side. apparatus.   2. A processing container that sealably defines the processing chamber, and pressure adjusting means for maintaining the internal pressure of the processing chamber at a pressure in a viscous flow region lower than atmospheric pressure. The plasma surface treatment apparatus according to any one of 6.

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