Film removing device and film removing method

Abstract

A film removal device (100) is provided with: a vacuum container (1) for accommodating an object to be treated (W1); an electrode (2) provided in the vacuum container (1) and having a first end (21) and a second end (22) disposed in a recess (W2) formed in the object to be processed (W1); a gas supply mechanism (4) that supplies gas from the first end (21) to the inside of the electrode (2); and a high-frequency power source (8) that applies a high-frequency voltage to the electrodes.

Description

Technical Field

[0001] The present disclosure relates to a film removing device and a film removing method. Background Art

[0002] In Patent Document 1, there is disclosed a plasma nitriding device for forming a nitride layer on the surface of a metal workpiece. This plasma nitriding device includes: a sealed processing container, a positive electrode provided in the processing container, and a conductive wire mesh provided so as to cover the workpiece and connected to the negative electrode. Recesses are formed in at least a part of the wire mesh, and an auxiliary positive electrode connected to the positive electrode is arranged in a space outside the wire mesh formed through the recesses.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2022-128655 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, when applying the structure of the plasma nitriding device disclosed in Patent Document 1 to a film removing device for removing a coating film formed in a recess of a workpiece, there are the following problems: the coating film removed in the recess adheres to the recess and the auxiliary positive electrode. An object of an embodiment of the present disclosure is to sufficiently remove the coating film formed in the recess of the workpiece.

[0008] Technical Means for Solving the Problems

[0009] To solve the above problems, a film removing device according to an embodiment of the present disclosure removes a coating film covering a workpiece from the workpiece by using plasma. The film removing device includes: a vacuum container that houses the workpiece therein; an electrode, which is a tubular electrode provided in the vacuum container with an insulating member interposed therebetween, and has a first end disposed outside the vacuum container and a second end disposed in a recess formed in the workpiece; a gas supply mechanism that ejects gas from the second end by supplying gas into the interior of the electrode from the first end; and a high-frequency power supply that generates plasma inside the vacuum container by applying a high-frequency voltage to the electrode.

[0010] In addition, to solve the above problems, a film removal method according to an embodiment of the present disclosure removes a film covering a workpiece from the workpiece using plasma. The film removal method includes: a placement step of placing the workpiece inside a vacuum chamber; a setup step of setting an electrode such that a first end of a tubular electrode that is provided in the vacuum chamber with an insulating member interposed therebetween is disposed outside the vacuum chamber and a second end of the electrode is disposed inside a recess formed in the workpiece; a gas supply step of supplying gas from the first end into the interior of the electrode and ejecting the gas from the second end; and an application step of applying a high-frequency voltage to the electrode to generate plasma inside the vacuum chamber.

[0011] Effects of the Invention

[0012] According to an embodiment of the present disclosure, a film covering a recess formed in a workpiece can be sufficiently removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a diagram showing the structure of a film removal apparatus according to Embodiment 1 of the present disclosure.

[0014] Figure 2 is a diagram showing the structure of a film removal apparatus according to Embodiment 2 of the present disclosure.

[0015] Figure 3 is Figure 2 a cross-sectional view taken along line A-A of the film removal apparatus shown.

[0016] Figure 4 is a diagram showing the structure of a film removal apparatus according to Embodiment 3 of the present disclosure.

[0017] Figure 5 is Figure 4 a cross-sectional view taken along line B-B of the film removal apparatus shown. DETAILED DESCRIPTION

[0018] 〔Embodiment 1〕

[0019] Figure 1 is a diagram showing the structure of a film removal apparatus 100 according to Embodiment 1 of the present disclosure. In Figure 1 , a cross-section of a vacuum chamber 1, an electrode 2, an insulating member 3, an insulating member 6, a bracket 5, and a support portion 51 is shown. In addition, in Figure 1 , the direction from the support portion 51 toward the vacuum exhaust device 10 is defined as the X-axis direction, the direction from the bracket 5 toward the electrode 2 is defined as the Z-axis direction, and the direction orthogonal to both the X-axis direction and the Z-axis direction is defined as the Y-axis direction. The X-axis direction and the Z-axis direction are orthogonal to each other. It is assumed that the definitions of the X-axis direction, the Y-axis direction, and the Z-axis direction described here are also applied in other figures.​​​​​

[0020] <Structure of the Film Removal Device 100>

[0021] The film removal device 100 is a device that uses plasma to remove the film covering the object to be processed W1 from the object to be processed W1. The object to be processed W1 is, for example, a mold for resin formation. As Figure 1 shown, the film removal device 100 includes: a vacuum chamber 1, an electrode 2, an insulating member 3, an insulating member 6, a gas supply mechanism 4, a bracket 5, a support portion 51, a pulse power supply 7, a high-frequency power supply 8, a matcher 81, a coil 9, and a vacuum exhaust device 10.

[0022] <Structure of the Vacuum Chamber 1 and the Electrode 2>

[0023] The vacuum chamber 1 is made of, for example, a metal material and houses the object to be processed W1 inside. The electrode 2 is formed in a tubular shape and has a first end 21 and a second end 22 opposite to the first end 21. The electrode 2 is disposed on the upper wall 1A on the positive Z-axis side of the vacuum chamber 1 with the insulating member 3 interposed therebetween. The first end 21 is disposed outside the vacuum chamber 1, and the second end 22 is disposed in the recess W2 formed on the upper surface W3 on the positive Z-axis side of the object to be processed W1. The extending direction of the electrode 2 is the Z-axis direction.

[0024] The second end 22 of the electrode 2 is preferably disposed at a position closer to the bottom of the recess W2 than the central position in the Z-axis direction in the recess W2. Thus, when the gas supply mechanism 4 supplies gas into the electrode 2, the removed film will not reattach to the recess W2, and the film in the recess W2 can be discharged to the outside of the recess W2.

[0025] In addition, the electrode 2 can branch into a plurality of tubes on the way from the first end 21 toward the negative Z-axis direction to form a plurality of second ends 22. Thus, when the gas supply mechanism 4 supplies gas into the electrode 2, gas can be ejected from the plurality of second ends 22 to a wide range of the recess W2.

[0026] <Structure of the Insulating Member 3 and the Insulating Member 6>

[0027] The insulating member 3 electrically insulates the vacuum chamber 1 from the electrode 2 and is disposed between the opening formed in the upper wall 1A of the vacuum chamber 1 and the electrode 2. A part of the electrode 2 is disposed in the opening hole 31 formed in the insulating member 3, and a plurality of vacuum sealing members 32 are provided between the electrode 2 and the opening hole 31. The plurality of vacuum sealing members 32 perform vacuum sealing between the electrode 2 and the opening hole 31.

[0028] The insulating member 6 electrically insulates the vacuum vessel 1 from the support portion 51, and is disposed between the opening formed in the lower wall 1B on the negative Z-axis side of the vacuum vessel 1 and the support portion 51. A part of the support portion 51 is disposed in the opening hole 61 formed in the insulating member 6, and a plurality of vacuum sealing members 62 are provided between the support portion 51 and the opening hole 61. The plurality of vacuum sealing members 62 vacuum-seal between the support portion 51 and the opening hole 61.

[0029] <Structure of the gas supply mechanism 4>

[0030] The gas supply mechanism 4 supplies gas from the first end 21 of the electrode 2 into the interior of the electrode 2, and ejects the gas from the second end 22 of the electrode 2. The gas supply mechanism 4 is connected to the first end 21 of the electrode 2 via an unillustrated insulating tube made of an insulating material such as resin, ceramic, or glass, and supplies the gas into the interior of the electrode 2 while controlling the gas to a desired flow rate.

[0031] The pressure inside the vacuum vessel 1 is adjusted by an unillustrated pressure regulating valve provided between the vacuum vessel 1 and the vacuum exhaust device 10. Preferably, the smaller the opening area of the upper surface W3 in the concave portion W2 of the object to be processed W1, the higher the pressure inside the vacuum vessel 1. Thereby, the coating film inside the concave portion W2 can be efficiently removed. The gas supply mechanism 4 preferably controls the pressure of the gas in the range of 0.5 Pa or more and 400 Pa or less.

[0032] The gas supplied by the gas supply mechanism 4 into the interior of the electrode 2 is, for example, an inert gas such as argon. Since the argon gas flow ejected from the second end 22 of the electrode 2 into the concave portion W2 becomes a viscous flow, it is easy to remove the coating film inside the concave portion W2. However, when the coating film covering the object to be processed W1 is a film containing carbon, the gas supplied by the gas supply mechanism 4 into the interior of the electrode 2 is preferably oxygen or a mixed gas of oxygen and argon. In addition, depending on the type of the coating film, the gas supplied by the gas supply mechanism 4 into the interior of the electrode 2 may be a mixed gas of a halide containing fluorine or chlorine and a noble gas.

[0033] <Structure of the support 5 and the support portion 51>

[0034] The support 5 is made of a metal material and is disposed inside the vacuum vessel 1 to support the object to be processed W1. The support 5 is supported by the support portion 51. The support portion 51 is disposed on the lower wall 1B with the insulating member 6 interposed therebetween and is made of a metal material. The end portion on the positive Z-axis side of the support portion 51 is connected to the support 5 inside the vacuum vessel 1, and the end portion on the negative Z-axis side of the support portion 51 is electrically connected to the pulse power supply 7 outside the vacuum vessel 1.

[0035] <Structure of the pulse power supply 7>

[0036] The pulsed power supply 7 is a DC pulsed power supply that applies a pulsed voltage mainly varying in the negative value range to the object to be processed W1. In other words, the pulsed power supply 7 is a DC pulsed power supply that periodically applies a mainly negative pulsed voltage to the object to be processed W1. During the pulsed operation, the pulsed power supply 7 applies a negative voltage in the ON (connected) state and applies a zero or positive voltage in the OFF (disconnected) state. The frequency of the pulsed voltage applied by the pulsed power supply 7 to the object to be processed W1 is preferably, for example, 75 kHz or more and 250 kHz or less.

[0037] By applying a negative pulsed voltage to the object to be processed W1 by the pulsed power supply 7 and applying a high-frequency voltage to the electrode 2 by the high-frequency power supply 8, the coating film in the recess W2 is removed by sputtering. The pulsed voltage applied by the pulsed power supply 7 to the object to be processed W1 is preferably -600 V or more and -100 V or less. The side of the pulsed power supply 7 opposite to the side connected to the support portion 51 is connected to the ground wire G1.

[0038] <Structure of the high-frequency power supply 8 and the matcher 81>

[0039] The high-frequency power supply 8 is a power supply for generating capacitive coupled plasma (CCP) inside the vacuum chamber 1 by supplying high-frequency power to the electrode 2 by applying a high-frequency voltage to the electrode 2. In a state where the second end 22 of the electrode 2 is disposed inside the recess W2 of the object to be processed W1, the high-frequency power supply 8 applies a high-frequency voltage to the electrode 2, thereby generating plasma inside the recess W2. The high-frequency power supply 8 is electrically connected to the first end 21 of the electrode 2 via the matcher 81.

[0040] The frequency of the high-frequency voltage applied by the high-frequency power supply 8 to the electrode 2 is preferably 13.56 MHz, for example. The side of the high-frequency power supply 8 opposite to the side connected to the matcher 81 is connected to the ground wire G2. The matcher 81 is an electrical circuit that matches the power from the high-frequency power supply 8 according to the load.

[0041] <Structure of the coil 9>

[0042] The coil 9 is connected in parallel with the electrode 2 and is electrically connected to the matcher 81. The side of the coil 9 opposite to the side connected to the matcher 81 is connected to the ground wire G3. By connecting the coil 9 in parallel with the electrode 2, plasma can be uniformly generated inside the recess W2 of the object to be processed W1, thereby suppressing the self-bias voltage of the electrode 2. Therefore, by applying a pulsed voltage mainly varying in the negative value range to the object to be processed W1 by the pulsed power supply 7 while suppressing the self-bias voltage of the electrode 2, positive ions in the plasma can be attracted to the recess W2, and thus the coating film inside the recess W2 can be removed more efficiently.

[0043] <Structure of the vacuum evacuation device 10>

[0044] The vacuum exhaust device 10 is a device that evacuates the inside of the vacuum container 1 from the discharge port 1C formed in the vacuum container 1, and is, for example, a vacuum pump. After evacuating the inside of the vacuum container 1 using the vacuum exhaust device 10, gas is introduced into the inside of the vacuum container 1 using the gas supply mechanism 4.

[0045] Based on the above, in the film removing device 100, the electrode 2 is disposed in the vacuum container 1 with the second end 22 of the electrode 2 disposed in the recess W2 formed in the object to be processed W1, with the insulating member 3 interposed therebetween. Thus, when a high-frequency voltage is applied to the electrode 2 using the high-frequency power supply 8, plasma can be generated in the recess W2. Therefore, by applying a pulse voltage to the object to be processed W1 using the pulse power supply 7, the film formed on the recess W2 can be sufficiently removed. In addition, since gas is ejected from the second end 22 of the electrode 2 disposed in the recess W2 using the gas supply mechanism 4, the film formed on the recess W2 can be efficiently discharged to the outside of the recess W2.

[0046] <Film removing method>

[0047] Hereinafter, a film removing method for removing the film covering the object to be processed W1 from the object to be processed W1 using plasma will be described. First, the object to be processed W1 is disposed on the support 5 provided inside the vacuum container 1 (disposing step). Next, the electrode 2 is disposed such that the first end 21 of the tubular electrode 2 disposed in the vacuum container 1 with the insulating member 3 interposed therebetween is disposed outside the vacuum container 1, and the second end 22 of the electrode 2 is disposed in the recess W2 formed in the object to be processed W1 (setting step).

[0048] After the electrode 2 is disposed in the vacuum container 1, the inside of the vacuum container 1 is evacuated using the vacuum exhaust device 10, and gas is supplied from the first end 21 to the inside of the electrode 2 using the gas supply mechanism 4, whereby gas is ejected from the second end 22 (gas supply step). After starting to supply gas using the gas supply mechanism 4, the pressure inside the vacuum container 1 is adjusted to a desired pressure using a pressure adjusting valve (not shown). Then, in order to generate plasma inside the vacuum container 1, a high-frequency voltage is applied to the electrode 2 using the high-frequency power supply 8 (applying step). After starting to apply the high-frequency voltage using the high-frequency power supply 8 and confirming the ignition of the plasma, a pulse voltage is applied to the object to be processed W1 using the pulse power supply 7.

[0049] 〔Embodiment 2〕

[0050] Hereinafter, Embodiment 2 of the present disclosure will be described. In addition, for ease of explanation, components having the same functions as those described in Embodiment 1 are denoted by the same reference numerals, and their descriptions will not be repeated. Figure 2 It is a diagram showing the structure of the film removing device 101 according to Embodiment 2 of the present disclosure. Figure 3 isFigure 2 A-A sectional view of the film removing device 101 shown. In Figure 2 , sectional views of a plurality of electrodes 2A, 2B, 2C and a plurality of insulating members 3A, 3B, 3C are shown.

[0051] As Figure 2 and Figure 3 shown, the difference between the film removing device 101 and the film removing device 100 is that: a plurality of objects to be processed WA, WB, WC, WD, WE are accommodated inside the vacuum container 1, and a plurality of electrodes 2A to 2E are included. In addition, the difference between the film removing device 101 and the film removing device 100 is that: a plurality of insulating members 3A to 3C are included, a plurality of coils 91, 92, 93 are included, and a plurality of variable capacitors C1, C2, C3 are included.

[0052] The vacuum container 1 is formed in a cylindrical shape, and a plurality of objects to be processed WA to WE are accommodated inside. The plurality of objects to be processed WA to WE are supported by a bracket 5. The bracket 5 is formed in a disc shape, for example. The objects to be processed WA to WE are preferably of the same structure as each other, and for example, may also have the same structure as the object to be processed W1 shown in Figure 1 . On the upper wall 1A of the vacuum container 1, a plurality of electrodes 2A to 2E are provided with an intervening insulating member.

[0053] Specifically, the electrode 2A is provided on the upper wall 1A with the intervening insulating member 3A, the electrode 2B is provided on the upper wall 1A with the intervening insulating member 3B, and the electrode 2C is provided on the upper wall 1A with the intervening insulating member 3C. In addition, the electrode 2D is provided on the upper wall 1A with an intervening insulating member not shown, and the electrode 2E is provided on the upper wall 1A with an intervening insulating member not shown.

[0054] The structures of the electrodes 2A to 2E are the same as the structure of the electrode 2 shown in Figure 1 , and the structures of the insulating members 3A to 3C are the same as the structure of the insulating member 3 shown in Figure 1 . The extending directions of the electrodes 2A to 2E are in the Z-axis direction. The film removing device 101 further includes: an insulating member provided between the electrode 2D and the upper wall 1A, and an insulating member provided between the electrode 2E and the upper wall 1A.

[0055] In the recesses formed in each of the plurality of objects to be processed WA to WE, the second ends of the electrodes 2A to 2E are disposed. Specifically, the second end 22A of the electrode 2A is disposed in the recess WA2 formed in the object to be processed WA, and the second end 22B of the electrode 2B is disposed in the recess WB2 formed in the object to be processed WB.

[0056] In addition, the second end 22C of the electrode 2C is disposed within the recess WC2 formed in the object to be processed WC. The second end of the electrode 2D is disposed within the recess WD2 formed in the object to be processed WD, and the second end of the electrode 2E is disposed within the recess WE2 formed in the object to be processed WE.

[0057] The gas supply mechanism 4 supplies gas from the first ends of the electrodes 2A to 2E into the electrodes 2A to 2E, whereby the gas is ejected from the second ends of the electrodes 2A to 2E. Specifically, the gas supply mechanism 4 is connected to the first end 21A of the electrode 2A via an unillustrated insulating tube including an insulating material such as resin, ceramic, or glass. In addition, the gas supply mechanism 4 supplies gas from the first end 21A into the electrode 2A, whereby the gas is ejected from the second end 22A.

[0058] Similarly, the gas supply mechanism 4 is connected to the first end 21B of the electrode 2B, the first end 21C of the electrode 2C, the first end of the electrode 2D, and the first end of the electrode 2E via insulating tubes having the same structure as the insulating tube. In addition, the gas supply mechanism 4 causes the gas to be ejected from the second end 22B, the second end 22C, the second end of the electrode 2D, and the second end of the electrode 2E. The gas supply mechanism 4 supplies gas to the interiors of the plurality of electrodes 2A to 2E equally at the same pressure.

[0059] The pulse power supply 7 applies a pulse voltage to the plurality of objects to be processed WA to WE via the bracket 5 and the support portion 51. The high-frequency power supply 8 applies a high-frequency voltage to the plurality of electrodes 2A to 2C via the matcher 81 and the variable capacitors C1 to C3, and applies a high-frequency voltage to the electrodes 2D and 2E via the matcher 81 and two unillustrated variable capacitors.

[0060] The electrodes 2A to 2E are connected in parallel with each other and are connected in series with the corresponding variable capacitors. The variable capacitor C1 is connected in series with the electrode 2A and is electrically connected between the electrode 2A and the matcher 81. The variable capacitor C2 is connected in series with the electrode 2B and is electrically connected between the electrode 2B and the matcher 81. The variable capacitor C3 is connected in series with the electrode 2C and is electrically connected between the electrode 2C and the matcher 81.

[0061] The other two variable capacitors are also respectively connected in series with the electrodes 2D and 2E and are electrically connected between the electrode 2D and the matcher 81 and between the electrode 2E and the matcher 81. The variable capacitors C1 to C3 and the other two variable capacitors are used to adjust or equalize the high-frequency power supplied to the plurality of electrodes 2A to 2E and are used to adjust or equalize the high-frequency voltage applied to the plurality of electrodes 2A to 2E. The film removing device 101 further includes the other two variable capacitors.

[0062] The coil 91 is connected in parallel with the electrode 2A and is electrically connected to the variable capacitor C1. The side of the coil 91 opposite to the side connected to the variable capacitor C1 is connected to the ground wire G31. The coil 92 is connected in parallel with the electrode 2B and is electrically connected to the variable capacitor C2. The side of the coil 92 opposite to the side connected to the variable capacitor C2 is connected to the ground wire G32.

[0063] Similarly, the coil 93 is connected in parallel with the electrode 2C, and the side of the coil 93 opposite to the side connected to the variable capacitor C3 is connected to the ground wire G33. For the electrodes 2D and 2E, they are also connected in parallel with the coil. The film removing device 101 further includes coils connected in parallel with the electrodes 2D and 2E.

[0064] In addition, the objects to be processed WA to WE can also be of different types from each other. In this case, the gas supply mechanism 4 can supply gas to the interiors of the plurality of electrodes 2A to 2E at different flow rates respectively, or can apply different high-frequency voltages to the plurality of electrodes 2A to 2E through the variable capacitors C1 to C3 and the other two variable capacitors.

[0065] According to the above, in the film removing device 101, the second ends of the electrodes 2A to 2E are disposed in the recesses formed in each of the plurality of objects to be processed WA to WE accommodated inside the vacuum container 1, and the high-frequency power supply 8 applies a high-frequency voltage to the plurality of electrodes 2A to 2E. Thereby, the coated film can be removed from the plurality of objects to be processed WA to WE, and the processing time can be shortened. In addition, since the high-frequency power supply 8 applies a high-frequency voltage to the plurality of electrodes 2A to 2E, the cost of the high-frequency power supply 8 can be reduced. For example, if there is only one high-frequency power supply 8, the cost of the high-frequency power supply 8 can be effectively reduced.

[0066] 〔Embodiment 3〕

[0067] Embodiment 3 of the present disclosure will be described below. In addition, for ease of explanation, components having the same functions as those described in Embodiment 1 and Embodiment 2 are denoted by the same reference numerals, and their descriptions are not repeated. Figure 4 FIG. is a diagram showing the structure of a film removing device 102 according to Embodiment 3 of the present disclosure. Figure 5 It is Figure 4 a sectional view taken along line B-B of the film removing device 102 shown. In Figure 4 it, cross-sections of the high-frequency windows 11A, 11C, the antennas 12A, 12C, and the shielding members 15A, 15C are shown. In addition, in Figure 4 it, the vacuum exhaust device 10 and the discharge port 1C are omitted.

[0068] As Figure 4 and Figure 5As shown, the difference between the film removing device 102 and the film removing device 101 lies in that: it includes a high-frequency window 11A, a high-frequency window 11C, a high-frequency window 11D, a high-frequency window 11E, includes an antenna 12A, an antenna 12C, an antenna 12D, an antenna 12E, and includes a cooling mechanism 13.

[0069] In addition, the difference between the film removing device 102 and the film removing device 101 lies in that: it includes a high-frequency power supply 14 and a matcher 141, includes a shielding member 15A, a shielding member 15C, a shielding member 15D, a shielding member 15E, and includes a rotating mechanism 16. Furthermore, the difference between the film removing device 102 and the film removing device 101 lies in that: the object to be processed WB is not arranged inside the vacuum container 1, and does not include an electrode 2B, a coil 92, and a variable capacitor C2.

[0070] <Structure of High-Frequency Windows 11A, 11C to 11E>

[0071] The high-frequency windows 11A, 11C to 11E are arranged on the wall surface of the vacuum container 1 along the extending directions of the electrodes 2A, 2C, 2D, 2E, and introduce the high-frequency magnetic field for generating plasma inside the vacuum container 1 into the inside of the vacuum container 1. Specifically, the high-frequency window 11A is arranged on the wall surface 1D of the vacuum container 1 along the Z-axis direction, and introduces the high-frequency magnetic field generated by the antenna 12A into the inside of the vacuum container 1.

[0072] In addition, the high-frequency window 11C is arranged on the wall surface 1E of the vacuum container 1 along the Z-axis direction, and introduces the high-frequency magnetic field generated by the antenna 12C into the inside of the vacuum container 1. Similarly, the high-frequency windows 11D, 11E are respectively arranged on the wall surface of the vacuum container 1 along the Z-axis direction, and introduce the high-frequency magnetic fields generated by the antennas 12D, 12E into the inside of the vacuum container 1.

[0073] The high-frequency window 11A includes a metal plate 111A and a dielectric plate 113A. A plurality of slits 112A are formed in the metal plate 111A, and the metal plate 111A is arranged in the vacuum container 1 so as to block the opening 1I formed in the wall surface 1D of the vacuum container 1. In addition, the dielectric plate 113A is arranged on the metal plate 111A so as to cover at least the slits 112A.

[0074] Similarly, the high-frequency window 11C includes a metal plate 111C and a dielectric plate 113C, the high-frequency window 11D includes a metal plate 111D and a dielectric plate 113D, and the high-frequency window 11E includes a metal plate 111E and a dielectric plate 113E. The structures of the metal plates 111C, 111D, 111E are the same as the structure of the metal plate 111A, and the structures of the dielectric plates 113C, 113D, 113E are the same as the structure of the dielectric plate 113A.

[0075] <Structure of Antennas 12A, 12C to 12E>

[0076] Antennas 12A, 12C to 12E are respectively arranged to face high-frequency windows 11A, 11C to 11E on the outside of vacuum chamber 1, generating a high-frequency magnetic field for generating inductively coupled plasma (ICP). Specifically, antenna 12A is formed in a linear shape, for example, and is made of a metal material such as copper. In addition, antenna 12A is arranged to face high-frequency window 11A on the outside of vacuum chamber 1 along the Z-axis direction. The structures of antennas 12C to 12E are the same as that of antenna 12A.

[0077] <Structure of Cooling Mechanism 13>

[0078] Cooling mechanism 13 includes a heat exchanger for adjusting the coolant circulating in circulation paths 131 and 132 to a constant temperature, and includes a pump for circulating the coolant in circulation paths 131 and 132. Circulation path 131 is provided inside antenna 12A through shielding member 15A. Circulation path 132 is provided inside antenna 12C through shielding member 15C.

[0079] Circulation paths 131 and 132 direct the joule heat generated in antennas 12A and 12C to the outside of antennas 12A and 12C. Thus, cooling mechanism 13 can cool antennas 12A and 12C whose temperatures rise due to the generation of joule heat. Therefore, the temperatures of antennas 12A and 12C can be maintained at an appropriate temperature. Similarly, cooling mechanism 13 adjusts the coolant circulating in the circulation paths provided inside antennas 12D and 12E to a constant temperature and circulates it.

[0080] <Structure of High-Frequency Power Supply 14 and Matching Unit 141>

[0081] High-frequency power supply 14 is a power supply for generating plasma inside vacuum chamber 1 by applying a high-frequency voltage to antennas 12A, 12C to 12E and supplying high-frequency power to antennas 12A, 12C to 12E. High-frequency power supply 14 is electrically connected to antennas 12A, 12C to 12E via matching unit 141.

[0082] The opposite side of the high-frequency power supply 14 from the side connected to the matcher 141 is connected to the ground wire G4. The matcher 141 is an electrical circuit that matches the power from the high-frequency power supply 14 according to the load. The opposite side of the antenna 12A from the side connected to the matcher 141 is connected to the ground wire G51, and the opposite side of the antenna 12C from the side connected to the matcher 141 is connected to the ground wire G52. The opposite sides of the antennas 12D and 12E from the sides connected to the matcher 141 are also connected to the ground wire.

[0083] <Structures of the shielding members 15A, 15C to 15E>

[0084] The shielding members 15A, 15C to 15E are respectively provided on the wall surface along the Z-axis direction in the vacuum vessel 1 so as to surround the antennas 12A, 12C to 12E and the high-frequency windows 11A, 11C to 11E.

[0085] <Structure of the rotating mechanism 16>

[0086] The rotating mechanism 16 includes a rotating table 161, a rotating table 162, a rotating table 163, a rotating table 164, and a rotating gear 165. The rotating tables 161 to 164 are rotatably provided on the support 5. Specifically, the rotating table 161 is formed in a disk shape, for example, and is made of a metal material. An unillustrated shaft made of a metal material is provided on the support 5, and the rotating table 161 is rotatably provided on this shaft. Similarly, the rotating tables 162 to 164 are also rotatably provided on the support 5.

[0087] The rotating table 161 is rotatably provided on the support 5 with the axis A1 overlapping the electrode 2A as the rotation axis, and the rotating table 162 is rotatably provided on the support 5 with the axis A2 overlapping the electrode 2C as the rotation axis. In addition, the rotating table 163 is rotatably provided on the support 5 with the axis A3 overlapping the electrode 2D as the rotation axis, and the rotating table 164 is rotatably provided on the support 5 with the axis A4 overlapping the electrode 2E as the rotation axis. The axes A1 to A4 are axes extending along the Z-axis direction. The objects to be processed WA, WC to WE are respectively arranged on the rotating tables 161 to 164.

[0088] The rotating gear 165 is movably arranged on the outer peripheral side of the support 5. The rotating gear 165 rotates in the R1 direction as shown while contacting the outer peripheral portions of the rotating tables 161 to 164. Figure 5 As a result, the rotating tables 161 to 164 rotate in the R2 direction as shown. The rotating mechanism 16 rotates the rotating tables 161 to 164 by rotating the rotating gear 165 using a drive mechanism (not shown). Figure 5

[0089] The rotation mechanism 16 rotates the object to be processed WA around the axis A1 by rotating the turntable 161, and rotates the object to be processed WC around the axis A2 by rotating the turntable 162. In addition, the rotation mechanism 16 rotates the object to be processed WD around the axis A3 by rotating the turntable 163, and rotates the object to be processed WE around the axis A4 by rotating the turntable 164.

[0090] According to the above, in the film removing device 102, high-frequency magnetic fields for generating plasma are introduced into the interior of the vacuum container 1 from the high-frequency windows 11A, 11C to 11E provided on the wall surface of the vacuum container 1 along the Z-axis direction, and the rotation mechanism 16 rotates the objects to be processed WA, WC to WE. Thereby, the coating films on the portions other than the concave portions of the objects to be processed WA, WC to WE can also be removed. That is, the coating films on the outer portions of the objects to be processed WA, WC to WE can also be uniformly removed, and the coating films on the concave portions and the outer portions can be concentratedly removed for the objects to be processed WA, WC to WE.

[0091] 〔Summary〕

[0092] The film removing device according to the first embodiment of the present disclosure is a film removing device that removes a coating film covering an object to be processed from the object to be processed by using plasma, and is configured to include: a vacuum container that houses the object to be processed therein; an electrode that is a tubular electrode provided in the vacuum container with an insulating member interposed therebetween, and has a first end disposed outside the vacuum container and a second end disposed in a concave portion formed in the object to be processed; a gas supply mechanism that ejects gas from the second end by supplying gas into the interior of the electrode from the first end; and a high-frequency power supply that generates plasma in the interior of the vacuum container by applying a high-frequency voltage to the electrode.

[0093] The film removing device according to the second embodiment of the present disclosure can be configured to further include, according to the first embodiment: a coil connected in parallel with the electrode; and a pulse power supply capable of applying a pulse voltage that varies within a negative value range to the object to be processed.

[0094] The film removing device according to the third embodiment of the present disclosure can be configured, according to the first embodiment or the second embodiment, such that: the vacuum container houses a plurality of the objects to be processed therein, a plurality of the electrodes are provided in the vacuum container with the insulating member interposed therebetween, and the second end of the electrode is disposed in the concave portion formed in each of the plurality of the objects to be processed, and the high-frequency power supply applies the high-frequency voltage to the plurality of the electrodes.

[0095] The film removing device according to the fourth embodiment of the present disclosure may be configured to further include, according to any one of the first to third embodiments: a high-frequency window provided on a wall surface along the extending direction of the electrode in the vacuum container, for introducing a high-frequency magnetic field for generating plasma inside the vacuum container into the inside of the vacuum container; an antenna provided to face the high-frequency window outside the vacuum container, for generating the high-frequency magnetic field; and a rotation mechanism for rotating the object to be processed around a rotation axis along the extending direction of the electrode.

[0096] The film removing method according to the fifth embodiment of the present disclosure is as follows: removing a film covering the object to be processed from the object to be processed by using plasma, the film removing method including: a placement step of placing the object to be processed inside a vacuum container; a setting step of setting the electrode such that a first end of a tubular electrode provided in the vacuum container with an insulating member interposed therebetween is arranged outside the vacuum container and a second end of the electrode is arranged inside a recess formed in the object to be processed; a gas supply step of supplying gas from the first end into the inside of the electrode and ejecting the gas from the second end; and an application step of applying a high-frequency voltage to the electrode to generate plasma inside the vacuum container.

[0097] The present disclosure is not limited to the above embodiments, and various modifications can be made within the scope defined by the claims. Embodiments obtained by appropriately combining technical means separately disclosed in different embodiments are also included in the technical scope of the present disclosure.

[0098] Description of reference numerals

[0099] 1: Vacuum container

[0100] 1D, 1E: Wall surface

[0101] 2, 2A - 2E: Electrode

[0102] 3, 3A - 3C: Insulating member

[0103] 4: Gas supply mechanism

[0104] 7: Pulse power supply

[0105] 8: High-frequency power supply

[0106] 9, 91 - 93: Coil

[0107] 11A, 11C - 11E: High-frequency window

[0108] 12A, 12C - 12E: Antenna

[0109] 16: Rotation mechanism

[0110] 21, 21A to 21C: First end

[0111] 22, 22A to 22C: Second end

[0112] 100 to 102: Film removing device

[0113] A1 to A4: Shaft

[0114] W1, WA to WE: Object to be processed

[0115] W2, WA2 to WE2: Concave portion

Claims

1. A film removing device that removes a film covering a workpiece to be processed from the workpiece using plasma. The film removing device is characterized in that it includes: a vacuum container that houses the workpiece to be processed therein; an electrode, which is a tubular electrode provided in the vacuum container with an insulating member interposed therebetween, and has a first end disposed outside the vacuum container and a second end disposed in a recess formed in the workpiece to be processed; a gas supply mechanism that ejects gas from the second end by supplying gas into the interior of the electrode from the first end; and a high-frequency power source that generates plasma inside the vacuum container by applying a high-frequency voltage to the electrode.

2. The film removing device according to claim 1, characterized in that it further includes: a coil connected in parallel with the electrode; and a pulse power source capable of applying a pulse voltage that varies within a negative value range to the workpiece to be processed.

3. The film removing device according to claim 1 or 2, characterized in that, the vacuum container houses a plurality of the workpieces to be processed therein, a plurality of the electrodes are provided in the vacuum container with the insulating member interposed therebetween, the second end of the electrode is disposed in the recess formed in each of the plurality of workpieces to be processed, and the high-frequency power source applies the high-frequency voltage to the plurality of electrodes.

4. The film removing device according to claim 1 or 2, characterized in that it further includes: a high-frequency window provided on a wall surface of the vacuum container along the extending direction of the electrode, which introduces a high-frequency magnetic field for generating plasma inside the vacuum container into the interior of the vacuum container; an antenna disposed to face the high-frequency window outside the vacuum container, which generates the high-frequency magnetic field; and a rotating mechanism that rotates the workpiece to be processed around a rotation axis along the extending direction of the electrode.

5. A film removing method that removes a film covering a workpiece to be processed from the workpiece using plasma. The film removing method is characterized in that it includes: a placement step of placing the workpiece to be processed inside a vacuum container; a setting step of setting the electrode such that a first end of the tubular electrode provided in the vacuum container with an insulating member interposed therebetween is disposed outside the vacuum container and a second end of the electrode is disposed in a recess formed in the workpiece to be processed; a gas supply step of ejecting gas from the second end by supplying gas into the interior of the electrode from the first end; and a processing step of applying a high-frequency voltage to the electrode in order to generate plasma inside the vacuum container.

Images