Plasma processing apparatus

Abstract

To provide a plasma processing apparatus capable of reducing damage to a fin member.SOLUTION: A plasma processing apparatus 1 includes an inner electrode 100, an electrode holder 200, an outer electrode 300, an insulating member 400 surrounding the inner electrode and the electrode holder, a fin member 500 for forming a swirling flow around the inner electrode by swirling a processing gas supplied inside the insulating member, and a nozzle 600 for blowing out the swirling flow that has been converted into plasma. The insulating member 400 is fixed directly or indirectly to the outer electrode 300, and the fin member 500 is fixed to the electrode holder 200 in a state spaced apart from the inner electrode 100, and is in contact with the inner circumferential surface of the insulating member 400.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a plasma processing apparatus. [Background technology]

[0002] For example, as seen in Japanese Utility Model Application Laid-Open Publication No. 6-54471, a plasma torch capable of swirling a processing gas is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 6-54471 Summary of the Invention [Problem to be solved by the invention]

[0004] In the plasma processing apparatus described in Japanese Utility Model Application Laid-Open Publication No. 6-54471, since the fin members are in contact with the electrodes and the nozzles, there is a concern that the fin members may be damaged by the effect of heat from the electrodes and the nozzles.

[0005] An object of the present disclosure is to provide a plasma processing apparatus capable of reducing damage to fin members. [Means for solving the problem]

[0006] A plasma processing apparatus according to one aspect of the present disclosure comprises an inner electrode to which a voltage is applied, an electrode holder that holds the inner electrode, an outer electrode formed in a cylindrical shape and surrounding the inner electrode and the electrode holder, an insulating member that is arranged between the inner electrode and the electrode holder and the outer electrode and surrounds the inner electrode and the electrode holder, a fin member for forming a swirling flow around the inner electrode by swirling a processing gas supplied inside the insulating member, and a nozzle that blows out the swirling flow that has been converted into plasma, wherein the insulating member is fixed directly or indirectly to the outer electrode, and the fin member is fixed to the electrode holder while being spaced apart from the inner electrode and is in contact with an inner surface of the insulating member. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide a plasma processing apparatus capable of reducing damage to fin members. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional perspective view of a plasma processing apparatus according to an embodiment of the present disclosure. [Diagram 2] 4 is a cross-sectional view showing the relationship between an inner electrode, an electrode holder, and an insulating member. FIG. [Diagram 3] FIG. 2 is an exploded perspective view of an electrode holder and a fin member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure will now be described with reference to the accompanying drawings, in which the same or corresponding components are designated by the same reference numerals.

[0010] 1 is a cross-sectional perspective view of a plasma processing apparatus according to an embodiment of the present disclosure, the plasma processing apparatus 1 being suitable for use in modifying the surface of a workpiece.

[0011] As shown in FIG. 1, the plasma processing apparatus 1 includes an inner electrode 100, an electrode holder 200, an outer electrode 300, an insulating member 400, a fin member 500, a nozzle 600, a gas supply unit 700, and an intermediate member 750.

[0012] The inner electrode 100 has a shape that extends linearly. The inner electrode 100 is made of, for example, tungsten. A voltage is applied to the inner electrode 100 from a power source (not shown).

[0013] The electrode holder 200 holds the inner electrode 100. The electrode holder 200 is made of, for example, copper. Details of the electrode holder 200 will be described later.

[0014] The outer electrode 300 is formed in a cylindrical shape. More specifically, the outer electrode 300 is formed in a cylindrical shape. The outer electrode 300 surrounds the inner electrode 100 and the electrode holder 200.

[0015] The insulating member 400 is disposed between the inner electrode 100 and the electrode holder 200 and the outer electrode 300. The insulating member 400 surrounds the inner electrode 100 and the electrode holder 200. The insulating member 400 is formed in a cylindrical shape. The insulating member 400 determines the position where plasma is generated between the inner electrode 100 and the outer electrode 300. As shown in FIG. 1, the position of the tip of the insulating member 400 is set at a position where the tip 101 of the inner electrode 100 is exposed from the tip. That is, the processing gas is turned into plasma in the vicinity of the tip 101 of the inner electrode 100.

[0016] Here, a detailed description will be given of the electrode holder 200. As shown in FIGS.

[0017] The outer holder 210 surrounds the inner electrode 100. As shown in Fig. 1, a tapered portion 211 is formed on the inner peripheral surface of the outer holder 210, the diameter of which gradually decreases toward the tip side (the downstream side in the flow direction of the process gas). As shown in Fig. 2, the outer peripheral surface of the outer holder 210 has a contact surface S1 that contacts the inner peripheral surface of the insulating member 400, and a flow path forming surface S2 that is spaced apart from the inner peripheral surface of the insulating member 400. The flow path forming surface S2 forms a flow path for the process gas together with the inner peripheral surface of the insulating member 400. As shown in Fig. 3, the flow path forming surface S2 is formed flat.

[0018] 1 and 3, the outer holder 210 has a holder 212 that holds the fin member 500. The holder 212 is formed on the downstream side of the flow passage forming surface S2 in the flow direction of the process gas.

[0019] The first inner holding body 220 is disposed inside the outer holding body 210. The first inner holding body 220 surrounds the inner electrode 100. As shown in Fig. 3, a slit S22 extending in a direction parallel to the axial direction of the first inner holding body 220 is formed at the tip of the first inner holding body 220. Therefore, when the first inner holding body 220 is inserted into the outer holding body 210, the tip 221 of the first inner holding body 220 is pressed by the reduced diameter portion 211 of the outer holding body 210 and is pressed against the inner electrode 100. As shown in Fig. 1, a reduced diameter portion 222 that gradually reduces in diameter toward the tip side is formed on the inner circumferential surface of the base end of the first inner holding body 220.

[0020] The second inner holding body 230 is disposed inside the outer holding body 210. The second inner holding body 230 surrounds the inner electrode 100. As shown in Fig. 3, a slit S23 extending in a direction parallel to the axial direction of the second inner holding body 230 is formed at the tip of the second inner holding body 230. For this reason, when the second inner holding body 230 is inserted into the outer holding body 210, the tip 231 of the second inner holding body 230 is pressed by the reduced diameter portion 222 of the first inner holding body 220 and is thereby brought into pressure contact with the inner electrode 100.

[0021] The fin member 500 is a member for forming a swirling flow around the inner electrode 100 by swirling a process gas (argon, air, etc.) supplied inside the insulating member 400. As shown in FIG. 3, a plurality of grooves 501 are formed on the outer peripheral surface of the fin member 500. The fin member 500 is held by the holding portion 212 of the electrode holder 200. As shown in FIG. 1, the outer peripheral surface of the fin member 500 is in contact with the inner peripheral surface of the insulating member 400. Therefore, the relative position of the holding portion 212 with respect to the insulating member 400 is effectively determined via the fin member 500. That is, the central axis of the inner electrode 100 coincides with the central axis of the insulating member 400 by the fin member 500, the outer holder 210, and the first inner holder 220.

[0022] 1, the fin member 500 is spaced apart from the inner electrode 100. Specifically, the fin member 500 has a held portion 510 and an extending portion 520.

[0023] The held portion 510 fits onto the outside of the holding portion 212. In other words, the held portion 510 fits onto the holding portion 212 from the outer circumferential side of the holding portion 212.

[0024] The extending portion 520 extends downstream in the flow direction of the gas to be treated from the held portion 510. An inner circumferential surface 500S of the extending portion 520 is spaced apart from the inner electrode 100, as shown in FIG.

[0025] 1, the length L between the fin member 500 and the tip 101 of the inner electrode 100 is preferably 3 to 10 times the inner diameter φ of the insulating member 400, and more preferably 5 to 7 times the inner diameter φ. In this way, the process gas is easily blown out of the nozzle 600 in a fully developed state. The length L refers to the length between the tip 101 of the inner electrode 100 and the downstream end of the groove 501 formed in the fin member 500.

[0026] The nozzle 600 is a portion that blows out a swirling flow that has been turned into plasma. The nozzle 600 is connected to the tip end of the outer electrode 300. The tip end (downstream end) 402 of the insulating member 400 is fixed to the nozzle 600.

[0027] The gas supply unit 700 is a portion for supplying a processing gas to the inside of the insulating member 400. The gas supply unit 700 is provided at a position spaced apart from the outer electrode 300 in a direction parallel to the central axis of the inner electrode 100.

[0028] 1, the intermediate member 750 is interposed between the gas supply unit 700 and the outer electrode 300. That is, the gas supply unit 700 is connected to the base end of the outer electrode 300 via the intermediate member 750. The intermediate member 750 has insulating properties. The base end 401 of the insulating member 400 is fixed to the intermediate member 750.

[0029] In the plasma processing apparatus 1 described above, when a processing gas is supplied from the gas supply unit 700, the processing gas flows into the inside of the insulating member 400 through a gap between the inner circumferential surface of the intermediate member 750 and the outer circumferential surface of the outer holder 210 of the electrode holder 200, passes between the insulating member 400 and the flow path forming surface S2, and reaches the fin member 500. Thereafter, the processing gas becomes a swirling flow around the inner electrode 100 by passing through the grooves 501 of the fin member 500, becomes plasma in the vicinity of the tip 101 of the inner electrode 100, and is blown out from the nozzle 600.

[0030] As described above, in the plasma processing apparatus 1 of this embodiment, a swirling flow is formed in the fin member 500, which lengthens the path along which the processing gas flows between the inner electrode 100 and the outer electrode 300, thereby generating stable plasma. Furthermore, since the insulating member 400 is fixed directly or indirectly to the outer electrode 300, and the fin member 500 is fixed to the electrode holder 200 and is in contact with the inner circumferential surface of the insulating member 400, misalignment of the central axis of the inner electrode 100 with respect to the outer electrode 300 is effectively suppressed.

[0031] Furthermore, since the inner electrode 100 is held at multiple points including the tip 221 of the first inner holding body 220 and the tip 231 of the second inner holding body 230, misalignment of the central axis of the inner electrode 100 relative to the outer electrode 300 is more reliably suppressed.

[0032] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0033] [Aspect 1] An inner electrode to which a voltage is applied; an electrode holder for holding the inner electrode; an outer electrode formed in a cylindrical shape and surrounding the inner electrode and the electrode holder; an insulating member disposed between the inner electrode and the electrode holder and the outer electrode, the insulating member surrounding the inner electrode and the electrode holder; a fin member for swirling a process gas supplied to an inside of the insulating member to form a swirling flow around the inner electrode; A nozzle for blowing out the plasmatized swirling flow, the insulating member is fixed directly or indirectly to the outer electrode; the fin member is fixed to the electrode holder while being spaced apart from the inner electrode, and is in contact with an inner circumferential surface of the insulating member.

[0034] In this plasma processing apparatus, the insulating member is fixed directly or indirectly to the outer electrode, and the fin member is fixed to the electrode holder while being spaced apart from the inner electrode and in contact with the inner peripheral surface of the insulating member, so that heat conduction from the inner electrode and the outer electrode to the fin member is suppressed, thereby suppressing damage and wear of the fin member.

[0035] [Aspect 2] The electrode holder is a contact surface that contacts an inner circumferential surface of the insulating member; 2. The plasma processing apparatus of claim 1, further comprising: a flow path forming surface that is spaced apart from an inner circumferential surface of the insulating member and that forms a flow path for the process gas together with the inner circumferential surface of the insulating member.

[0036] In this manner, the position of the electrode holder relative to the insulating member is effectively determined.

[0037] [Aspect 3] the electrode holder has a holder portion for holding the fin member, 3. The plasma processing apparatus according to aspect 2, wherein the holding portion is formed on a downstream side of the flow passage forming surface in a flow direction of the process gas.

[0038] [Aspect 4] a gas supply unit that is provided at a position spaced apart from the outer electrode in a direction parallel to a central axis of the inner electrode and that supplies the processing gas; an intermediate member interposed between the gas supply unit and the outer electrode, a base end of the insulating member is fixed to the intermediate member, 4. The plasma processing apparatus of claim 1, wherein a tip of the insulating member is fixed to the nozzle.

[0039] [Aspect 5] 5. The plasma processing apparatus of claim 1, wherein a length between the tips of the fin member and the inner electrode is 5 to 20 times the inner diameter of the insulating member.

[0040] It should be noted that the embodiments disclosed herein are illustrative in all respects and should not be considered as limiting. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0041] 1 plasma processing apparatus, 100 inner electrode, 200 electrode holder, 210 outer holder, 220 first inner holder, 230 second inner holder, 300 outer electrode, 400 insulating member, 401 base end, 402 tip end, 500 fin member, 510 held portion, 520 extension portion, 600 nozzle, 700 gas supply portion, 750 intermediate member.

Claims

1. an inner electrode to which a voltage is applied; an electrode holder for holding the inner electrode; an outer electrode formed in a cylindrical shape and surrounding the inner electrode and the electrode holder; an insulating member disposed between the inner electrode and the electrode holder and the outer electrode, the insulating member surrounding the inner electrode and the electrode holder; a fin member for swirling a process gas supplied to an inside of the insulating member to form a swirling flow around the inner electrode; A nozzle for blowing out the plasmatized swirling flow, the insulating member is fixed directly or indirectly to the outer electrode; the fin member is fixed to the electrode holder while being spaced apart from the inner electrode, and is in contact with an inner circumferential surface of the insulating member.

2. The electrode holder is a contact surface that contacts an inner circumferential surface of the insulating member; 2 . The plasma processing apparatus according to claim 1 , further comprising: a flow passage forming surface spaced apart from an inner circumferential surface of the insulating member and forming a flow passage for the process gas together with the inner circumferential surface of the insulating member.

3. the electrode holder has a holder portion for holding the fin member, The plasma processing apparatus according to claim 2 , wherein the holding portion is formed on a downstream side of the flow passage forming surface in a flow direction of the process gas.

4. a gas supply unit that is provided at a position spaced apart from the outer electrode in a direction parallel to a central axis of the inner electrode and that supplies the processing gas; an intermediate member interposed between the gas supply unit and the outer electrode, a base end of the insulating member is fixed to the intermediate member, The plasma processing apparatus according to claim 1 , wherein a tip end of the insulating member is fixed to the nozzle.

5. 2 . The plasma processing apparatus according to claim 1 , wherein a length between the tips of the fin member and the inner electrode is between 3 and 10 times an inner diameter of the insulating member.

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