Evaporation source device for vacuum arc vapor deposition and vacuum arc vapor deposition device

Abstract

[Problem] To provide a device that can use a plurality of trigger electrodes without having a complicated structure and that can produce an arc discharge even after significant local depletion. [Solution] An evaporation source device for vacuum arc vapor deposition according to the present invention comprises a negative electrode 11 that is an evaporation source and a plurality of trigger electrodes 5a–5c that are provided opposite a discharge surface 11a of the negative electrode to induce arc discharge. The plurality of trigger electrodes are supported by the same rotary shaft 6, and at least one of the tips of the plurality of trigger electrodes can be brought into contact with the discharge surface of the negative electrode by rotation of the rotary shaft. The plurality of trigger electrodes are arranged such that one trigger electrode is opposite each of a plurality of section regions that are formed by sectioning the discharge surface into arbitrary regions in accordance with the number of trigger electrodes. A vacuum arc vapor deposition device according to the present invention has the evaporation source device installed at a plasma generation means.

Description

Evaporation source device for vacuum arc deposition and vacuum arc deposition device

[0001] The present invention relates to a vacuum arc deposition apparatus and an evaporation source device for vacuum arc deposition, and in particular to an apparatus having a plurality of trigger electrodes arranged for inducing arc discharge. The trigger electrodes, which once mechanically contact the cathode, are sometimes called "strikers."

[0002] In a vacuum arc deposition apparatus, a technique for generating an arc discharge between a cathode and an anode is described in Patent Document 1, in which a trigger electrode for inducing an arc discharge is disposed opposite the discharge surface of the cathode, and an arc discharge is generated by igniting and then extinguishing an arc between the two electrodes. In addition to this mechanical contact ignition method, there is also a method (electrical trigger method) in which a high voltage or a pulse voltage is applied to generate an electrical spark to induce a vacuum arc discharge.

[0003] However, in a vacuum arc deposition apparatus using a mechanical trigger to induce a vacuum arc, the cathode is consumed, and repeated discharges by the trigger electrode result in localized wear of the discharge surface formed by the tip surface of the cathode. This localized wear of the discharge surface results in erosion into a concave shape, which can cause poor or incomplete contact of the trigger electrode with the discharge surface, making it impossible to induce an arc discharge. To address this problem, a technology has been developed that uses multiple trigger electrodes to limit localized wear of the discharge surface (see Patent Document 2).

[0004] JP 2004-169132 A JP 2002-206162 A

[0005] According to the explanation in Patent Document 1, the technology disclosed in Patent Document 2 suppresses significant local wear of the discharge surface by arranging multiple trigger electrodes on the discharge surface of the cathode and selectively switching between these trigger electrodes, but has the problem of requiring a device to individually drive the multiple trigger electrodes. Therefore, the technology disclosed in Patent Document 1 divides the cathode into an outer tube and a core, and configures the core to be movable along the outer tube toward the trigger electrode, and makes the core rotatable around its axis.

[0006] However, the invention disclosed in Patent Document 1 was basically intended to enable use for as long as possible without replacing the cathode even when using a single trigger electrode, and was configured so that the core portion was movable along the outer tube portion. Therefore, an additional configuration was required to ensure airtightness between the outer tube portion and the core portion. That is, since a vacuum arc evaporation device vaporizes a cathode material by arc discharge in a depressurized chamber (vacuum chamber) and generates plasma containing the ionized cathode material to form a film of the cathode material on the surface of a film-forming target, it is essential to maintain a depressurized state within the vacuum chamber, and a mechanism for achieving this must be considered.

[0007] Furthermore, since the above invention is based on the principle of using only one trigger electrode, even if the core is rotated, it is not possible to completely eliminate local wear, and if the contact of the single trigger electrode becomes poor, continuous (long-term) use of the cathode becomes difficult.

[0008] The invention disclosed in Patent Document 2 has a configuration in which the trigger electrode is bent into a hook shape and the base (shank) of the trigger electrode moves back and forth along its axial direction (the base end of the shank extends and retracts). Therefore, when the tip of the trigger electrode is brought into contact with the end face of the cathode to induce an arc discharge, a reaction force from the end face of the cathode acts as a bending stress on the shank of the trigger electrode, which may deform the shank or the airtight seal. In addition, every time the base end of the trigger electrode extends and retracts (every time the shank is advanced or retracted), small external particles (dust, etc.) are mixed into the airtight seal (by being sucked in due to the pressure difference between the inside of the vacuum chamber and the outside air), which increases the resistance during the advance and retract movement and causes malfunction. In addition, repeated advance and retraction movements may cause scratches on the shank, which may cause deterioration of the airtight seal.

[0009] The present invention has been made in view of the above points, and its object is to provide an apparatus which can use multiple trigger electrodes without a complicated mechanism and which can generate an arc discharge even when there is significant localized wear.

[0010] Therefore, the first invention relating to an evaporation source device for vacuum arc evaporation is a vacuum arc evaporation device for generating plasma by causing an arc discharge between a cathode and an anode connected via a power supply in a vacuum, and evaporating a cathode material that constitutes the cathode to perform evaporation processing, the vacuum arc evaporation device comprising: a cathode that is an evaporation source; and a plurality of trigger electrodes arranged to induce arc discharge and facing the discharge surface of the cathode, the plurality of trigger electrodes being supported on the same rotating shaft connected to a single power supply and a single current limiting resistor, so that at least one of the tips of the plurality of trigger electrodes can come into contact with the discharge surface of the cathode by rotation of the rotating shaft, and when the discharge surface is divided into any number of regions according to the number of trigger electrodes and segmented regions are set, one trigger electrode is arranged to face each of the segmented regions.

[0011] According to the above configuration, the tips of multiple trigger electrodes can be simultaneously brought close to the discharge surface of the cathode by a rotating shaft rotatable within a vacuum chamber, and an arc discharge can be generated when any of the multiple trigger electrodes contacts the discharge surface. A drive source for rotating the rotating shaft can be provided outside the vacuum chamber, and the base of the rotating shaft can be connected to the drive source externally while the rotating shaft penetrates the wall of the vacuum chamber. The main body of the rotating shaft can support the trigger electrodes within the vacuum chamber. Since the rotating shaft can be machined to have a smooth surface, the rotating shaft only rotates without sliding in the forward and backward directions during operation (rotation), and airtightness between the wall of the vacuum chamber and the rotating shaft can be easily ensured by a seal structure around the rotating shaft. In particular, unlike the technology disclosed in Patent Document 2, the shaft of the trigger electrode does not move forward and backward along its axial direction. Therefore, even when the tip of the trigger electrode contacts the end surface of the cathode to initiate an arc discharge, bending stress is not applied to the shaft of the trigger electrode, eliminating the causes of deformation of the shaft or airtight seal or the intrusion of small external particles (such as dust).

[0012] The tips of the multiple trigger electrodes supported by the rotating shaft are configured to approach and move away from the discharge surface of the cathode as the rotating shaft rotates, so they move along an arc-shaped trajectory centered on the axis of the rotating shaft. Therefore, the movement range of the trigger electrode tips can be adjusted by presetting the rotation angle of the rotating shaft. In particular, when the discharge surface of the cathode is worn away by repeated contacts, the additional movement range corresponding to the worn portion (the recessed portion) can be adjusted by adjusting the rotation angle of the rotating shaft. Furthermore, because each trigger electrode is provided so as to be contactable in a predefined divided region, even if some of the trigger electrodes have poor contact due to localized wear on the discharge surface, the other divided regions (with less wear) are inevitably selected, allowing the entire discharge surface to be utilized without the need for a special mechanism.

[0013] A second aspect of the present invention, which relates to an evaporation source device for vacuum arc evaporation, is the first aspect of the present invention, wherein the rotation shaft is rotatable about an axis parallel to an imaginary plane including the discharge surface, the plurality of trigger electrodes are protruded from the rotation shaft, and the gaps between the tips of the plurality of trigger electrodes as they approach the discharge surface are adjusted to be approximately uniform by the rotation of the rotation shaft.

[0014] According to the above configuration, since the axis of the rotation shaft is parallel to an imaginary plane including the discharge surface, the same type of trigger electrode (trigger electrodes of the same length and supported at the same angle) can be used for contact points on the discharge surface that are equidistant from the rotation shaft. In this case, a linear trigger electrode (one that does not require bending) can be used. Furthermore, even when trigger electrodes are used for contact points that are located at different distances from the rotation shaft, this can be accommodated by simply adjusting the length, the angle, or both, and linear trigger electrodes can be used in the same way.

[0015] The term "virtual plane including the discharge surface" refers to a plane obtained by virtually expanding the discharge surface of the cathode, which is formed as a smooth edge. Furthermore, the term "substantially the same" for the gaps between the tips of the trigger electrodes and the discharge surface does not necessarily mean that the gaps are completely the same, but rather that they are roughly the same. By having these gaps be substantially the same, when multiple trigger electrodes move around the same rotation axis and their tips simultaneously approach the discharge surface of the cathode, even if the discharge surface is already locally worn and one of the trigger electrodes has poor contact, the other trigger electrodes can still make contact, thereby ensuring the generation of an arc discharge. Furthermore, by intentionally varying the gaps between the tips of the multiple trigger electrodes and the discharge surface of the cathode (while still maintaining substantially the same gaps), it is possible to intentionally adjust the order in which the trigger electrodes make contact with the discharge surface.

[0016] The third invention relating to the evaporation source device for vacuum arc evaporation is the second invention, wherein the divided areas are fan-shaped areas divided from the center point of a circular discharge surface at equal angles equal to the number of the plurality of trigger electrodes.

[0017] According to the above configuration, a wide range of the discharge surface of the cathode, which is configured as a circular end surface, can be used by the trigger electrode. Even in this case, the center of the discharge surface may be separated from the segmented areas, and the center and its surrounding segmented areas may be used. When dividing the discharge surface into segmented areas, the number of divisions may be adjusted according to the area of ​​the discharge surface, and trigger electrodes may be installed according to the number of segmented areas.

[0018] A fourth aspect of the present invention, which relates to an evaporation source device for vacuum arc evaporation, is the third aspect of the present invention, wherein the trigger electrodes are erected in a direction perpendicular to the axis of the rotation shaft, and the length and angle of each trigger electrode are adjusted so that they can individually contact approximately the center of the divided region.

[0019] According to the above configuration, the trigger electrodes supported on the rotating shaft are supported perpendicular to the axis of the rotating shaft, so the spacing between the tips of the trigger electrodes is determined depending on the spacing at which the trigger electrodes are installed on the rotating shaft. When the points at which the tips of the trigger electrodes contact the discharge surface are linear, all of the trigger electrodes can be installed with the same length and angle. However, when the segmented regions are fan-shaped, as in the third invention, contacting the electrodes at approximately the center of each segmented region is not possible simply by using trigger electrodes with the same length and angle. Therefore, by appropriately adjusting the length and angle, it is possible to easily contact the approximately center of each segmented region. Note that "approximately the center" does not necessarily mean the exact center, but rather includes the periphery of the center.

[0020] A fifth aspect of the present invention relating to an evaporation source device for vacuum arc evaporation is the second aspect of the present invention, wherein the divided areas are areas separated equidistantly by imaginary planes perpendicular to the axis of the rotation shaft with respect to a discharge surface of any shape.

[0021] According to the above configuration, even if the shape of the cathode discharge surface is not a circular plane, such as a rectangle, it is not possible to conceive of fan-shaped partitioned regions. However, even in such cases, appropriate partitioned regions can be formed. That is, for a non-circular discharge surface such as a rectangle, partitioned regions can be formed by dividing the surface into imaginary planes perpendicular to the axis of the rotation shaft. In this case, by conceiving multiple imaginary planes perpendicular to the rotation shaft and setting them at equal intervals, it is possible to set partitioned regions that divide the discharge surface at equal intervals. In the case of a non-circular shape, particularly a rectangular shape, by aligning the axis of the rotation shaft with the long side, it is possible to divide the rectangular surface into equal parts with equal areas along the long side. Note that the imaginary plane perpendicular to the axis of the rotation shaft refers to a plane that is assumed to be perpendicular to the axis of the rotation shaft. Since the axis of the rotation shaft is set parallel to the imaginary plane containing the discharge surface, the imaginary plane perpendicular to the rotation shaft is also a plane that is perpendicular to the heat dissipation surface.

[0022] A sixth aspect of the present invention relating to an evaporation source device for vacuum arc evaporation is the fifth aspect of the present invention, wherein the trigger electrodes are erected in a direction perpendicular to the axis of the rotation shaft, and the lengths and angles of the individual trigger electrodes are adjusted to be approximately the same so that they can individually contact approximately the centers of the divided regions.

[0023] The above configuration is basically the same as that of the fourth invention, and since the trigger electrodes are supported perpendicular to the axis of the rotation shaft, the spacing between the tips of the trigger electrodes can be determined according to the spacing defined by the fifth invention. Furthermore, if the tips of the trigger electrodes are arranged linearly, all of the trigger electrodes may be installed with the same length and angle, but if the divided regions have an irregular shape, the length and angle may be adjusted.

[0024] The seventh aspect of the present invention, which relates to an evaporation source device for vacuum arc evaporation, is configured such that, in any one of the first to sixth aspects, the rotation shafts are provided at two locations facing each other with the discharge surface of the cathode at the center, and approximately half of the number of the plurality of trigger electrodes are provided separately on the two rotation shafts.

[0025] According to the above configuration, for example, when multiple trigger electrodes are arranged on a large discharge surface, by providing two opposing rotational axes, it is possible to prevent the trigger electrodes from being crowded together. The rotational axis does not have to be a single axis; therefore, multiple rotational axes can be used, with several trigger electrodes supported on each individual rotational axis. Regardless of whether this is necessary, the rotational axis can also be provided in three or four locations. Therefore, the present invention also encompasses a configuration in which multiple trigger electrodes are supported on each of multiple rotational axes. Note that "approximately half" means half when the number of trigger electrodes is even, and an error of one electrode occurs when the number is odd, so this includes both situations.

[0026] The eighth aspect of the present invention, which relates to an evaporation source device for vacuum arc evaporation, is the same as the seventh aspect of the present invention, except that the divided area is divided into two halves on the side where the two rotation axes are provided by a straight line including the center point of the discharge surface, and the area close to the rotation axes is divided according to the number of trigger electrodes provided on each rotation axis.

[0027] According to the above configuration, when two rotating shafts are provided facing each other with respect to the cathode, the discharge surface can be divided into two halves on the side where the rotating shafts are provided, and each half can be set as a segmented area, thereby preventing the trigger electrodes protruding from the opposing rotating shafts from coming into contact with each other. Note that even in this case, the center of the discharge surface may be excluded from the segmented areas, and the central part may be used as a contact point for the trigger electrodes, separate from the peripheral segmented areas other than the center.

[0028] The present invention relates to a vacuum arc evaporation apparatus that includes any one of the evaporation source devices described above in the first to sixth aspects. By including any one of these evaporation source devices in a vacuum arc evaporation apparatus, the above-mentioned effects can be achieved.

[0029] According to the present invention, an arc discharge can be generated simply by rotating a rotating shaft. All that is required is a drive device and a transmission mechanism for driving the rotation of the rotating shaft. This allows multiple trigger electrodes to extinguish the arc at multiple locations on the cathode's discharge surface without requiring a complex mechanism. Furthermore, because multiple trigger electrodes approach the discharge surface simultaneously via the same rotating shaft, even if some contact points are significantly worn locally, arc discharge can be generated by the contact of other trigger electrodes. As a result, the same cathode can be used for a long period of time, thereby extending the life of the material and contributing to cost reduction.

[0030] Furthermore, according to the present invention relating to the vacuum arc deposition apparatus, it is possible to easily induce arc discharge, which allows the cathode to be used for a long period of time, thereby reducing the running costs when using the entire apparatus.

[0031] 1 is an explanatory diagram showing an outline of a vacuum arc evaporation apparatus; FIG. 2 is a simplified cross-sectional view of the section shown by line II-II in FIG. 1; FIG. 3 is an explanatory diagram showing details of a power transmission unit; FIG. 4 is an explanatory diagram showing the positional relationship between the discharge surface of the cathode, the rotation shaft, and the trigger electrode; FIG. 5 is an explanatory diagram showing the operation mode of the rotation shaft and the trigger electrode; FIG. 6 is an explanatory diagram showing the operation mode of the rotation shaft and the trigger electrode; FIG. 7 is an explanatory diagram showing the relationship between the wear state of the discharge surface due to arc discharge and the state of the trigger electrode; FIG. 8 is an explanatory diagram showing the relationship between the wear state of the discharge surface due to arc discharge and the state of the trigger electrode; FIG. 9 is an explanatory diagram showing a first modified embodiment of an evaporation source device; FIG. 10 is an explanatory diagram showing a first modified embodiment of an evaporation source device; FIG. 11 is an explanatory diagram showing a first modified embodiment of an evaporation source device; FIG. 12 is an explanatory diagram showing a second modified embodiment of an evaporation source device; FIG. 13 is an explanatory diagram showing the results of Experimental Example 1; FIG. 14 is an explanatory diagram showing the results of Experimental Example 2; FIG. 15 is an explanatory diagram showing the results of a comparative example; FIG. 16 is an explanatory diagram showing another modified embodiment (a modified shape of the trigger electrode); FIG. 17 is an explanatory diagram showing another modified embodiment (a modified shape of the trigger electrode).

[0032] An embodiment of the present invention will now be described with reference to the drawings. <Vacuum Arc Evaporation Apparatus> The present invention relates to an evaporation source device for vacuum arc evaporation and a vacuum arc evaporation apparatus. First, an outline of the vacuum arc evaporation apparatus will be described. FIG. 1 is a diagram showing an outline of the vacuum arc evaporation apparatus. As shown in FIG. 1, the vacuum arc evaporation apparatus comprises a plasma generation means 1, a plasma duct 2 that serves as a transport path for evaporated particles formed by evaporation of a cathode material by the plasma generation means, and a film formation chamber 3 for film formation. The plasma generation means 1 includes a cathode 11 and an anode 12 disposed nearby, each of which is connected to an external arc power supply 13 via an insulated lead-in terminal 4 to enable arc discharge. The evaporation source device of the present invention is an apparatus used in the plasma generation means 1.

[0033] The cathode 11 is made of a film-forming material, and corresponds to a target (evaporation source). The cathode 11 is configured to also function as a target, but the film-forming material serving as the target may be separately disposed on the surface of the cathode 11. The material constituting the cathode 11 also serving as a target is not particularly limited as long as it is a conductive solid, and may be a metal element, an alloy, an inorganic element, an inorganic compound, or the like. These may be used alone or as a mixture of two or more types.

[0034] The trigger electrode 5 is disposed near the cathode 11 so as to face the discharge surface at its tip, and is used to induce a vacuum arc between the cathode 11 and the anode 12. Specifically, the trigger electrode 5 is temporarily brought into contact with the tip surface (discharge surface) of the cathode 11 (ignition) and then separated (extinguishing), generating an electric spark between the cathode 11 and the trigger electrode 5. When the electric spark is generated, the electrical resistance between the cathode 11 and the anode 12 decreases, generating a vacuum arc between the electrodes 11 and 12. The trigger electrode 5 is connected to the positive electrode of the arc power supply 13 via a trigger current limiting resistor 14. Since the deposition chamber 3 typically doubles as the anode 12, the anode 12 shown in the figure may be omitted, and the vacuum chamber, i.e., the metal deposition chamber 3, may be connected to the anode side of the arc power supply 13. Furthermore, depending on the purpose, a configuration may be adopted in which both an independent anode 12 and a metal film-forming chamber 3 that can serve as an anode are provided (see FIG. 2).

[0035] The trigger electrode 5 in this embodiment, as will be described in detail later, is composed of multiple electrode rods supported by a rotating shaft 6, and is configured so that, as the rotating shaft 6 rotates, it can face and contact (ignite) the discharge surface of the cathode 11, and can also move away (extinguish) to a large distance, thereby being removed from the discharge surface of the cathode 11. A drive unit 7 for rotating the rotating shaft 6 is provided outside the plasma generating means 1 (apparatus wall), and the rotating shaft 6, to which the driving force of the drive unit 7 is transmitted, penetrates the apparatus wall via an airtight seal 8 while ensuring insulation and airtightness. An O-ring can be used as the airtight seal 8. To further increase airtightness, multiple O-rings may be used.

[0036] The anode 12 may be made of any conductive material that can withstand temperatures of approximately 200°C, and is not limited to this material. Metals, alloys, inorganic elements, inorganic compounds, etc. can be used, and the materials exemplified for the cathode can be appropriately selected and used. These can be used alone or as a mixture of two or more types. For example, stainless steel, soft iron, steel, copper, copper alloys, aluminum, aluminum alloys, graphite, etc. can be used. If the temperature becomes high, it is preferable to provide a cooling mechanism for cooling (water cooling, etc.).

[0037] The region that serves as the transport path for the evaporated particles is formed inside the anode 12, which is formed in a substantially cylindrical shape. Although not shown, a magnetic field generating unit using an electromagnet can be provided on the outer periphery of the substantially cylindrical anode 12. This generates an induced magnetic field that guides charged particles generated by evaporation of the film-forming material in a predetermined direction. The induced magnetic field at this time is oriented along the central axis of the substantially cylindrical anode 12.

[0038] The charged particles are guided in the region that becomes the transport path in a linear direction from the cathode 11 along the central axis of the approximately cylindrical anode 12, and are supplied to the workpiece A inside through the opening of the film formation chamber 3 located in front. Note that although the transport path is illustrated as being linear, it may also be configured to be curved in an L-shape.

[0039] The film-forming chamber 3 is open on the side facing the plasma generating means 1, and is equipped inside with a workpiece holding means 31 for holding workpieces A, B, ..., H. By intermittently rotating this workpiece holding means 31, multiple workpieces A to H can be placed in succession facing the plasma generating means 1 and subjected to film-forming processing.

[0040] <Embodiment of Evaporation Source Device for Vacuum Arc Deposition> FIG. 2 is a simplified cross-sectional view of the cross section shown by line II-II in FIG. 1 . An embodiment of the evaporation source device will now be described with reference to FIG. 2 . As shown in FIG. 2 , the evaporation source device of this embodiment is configured inside plasma generation means 1. A trigger electrode 5 is supported by a rotating shaft 6, and its tip is positioned opposite a tip surface (discharge surface) 11 a of a cathode 11. The rotating shaft 6 is connected to a driving device 7 outside the plasma generation means 1 and is rotatable by receiving driving forces transmitted in forward and reverse directions from the driving device 7. Furthermore, the forward and reverse rotation of the driving device 7 is controlled by a trigger control mechanism 9, which controls the timing, rotation speed, rotation angle, and the like of the rotation. In particular, if the trigger electrode 5 is pressed too hard against the cathode 11 (discharge surface 11 a), the trigger electrode 5 will bend and become bent, so that the rotational drive can be controlled to stop at a predetermined state by feeding back the reaction force generated when the trigger electrode 5 comes into contact with the cathode 11 (discharge surface 11 a) due to rotation, or by detecting the passage of electricity due to contact. Note that, as the drive device 7, an air motor or a hydraulic motor, etc., can be used in addition to a servo motor, and a pneumatic or hydraulic actuator, etc., can also be used in addition to an electric actuator.

[0041] FIG. 3 shows an example of a power transmission unit 60 for transmitting driving force from the drive unit 7 to the rotating shaft 6. Because various components are arranged outside the plasma generating means 1, it may not be possible to arrange the drive shaft linearly (so as to be directly connected to the drive unit), so this is an example of a case in which power is transmitted by the drive transmission unit 60. Therefore, if the driving force can be transmitted linearly, there is no need to provide a separate unit. However, if the driving force can be transmitted linearly, it is possible to transmit the driving force by providing an appropriate unit. Therefore, as an example, as shown in FIG. 3, a power transmission unit 60 is provided to transmit the driving force appropriately. Specifically, a drive shaft 61 driven by the drive unit is supported by the power transmission unit 60 with a sleeve 62 interposed therebetween, and a bevel gear 63 is connected to the tip of this drive shaft 61. By meshing a bevel gear (driven side) 64 with the same number of teeth with the drive side bevel gear 63, the rotating shaft is changed to an angular shape (vertical), and this driven side bevel gear 64 is connected to the base end of the rotating shaft 6 and is supported by the power transmission unit 60 near the base end with a sleeve 65 interposed therebetween. The rotating shaft 6 is configured to support a plurality of trigger electrodes 5a, 5b, 5c (three in the figure) in a state where they penetrate the rotating shaft 6, and rotation of the rotating shaft 6 allows all of the trigger electrodes 5a, 5b, 5c to move simultaneously.

[0042] By changing the rotation direction of the drive shaft 61 using the two bevel gears 63 and 64 in this manner, a rotational driving force can be transmitted from the vicinity of the cathode 11 to the rotating shaft 6, thereby avoiding interference with other external components. The airtight seal 8 ensures airtightness between the inside and outside of the rotating shaft 6. This airtight seal 8 is formed of an annular sleeve body with two O-rings 81 and 82 interposed on its inner circumferential surface. By inserting the rotating shaft 6 into the plasma generating means 1 (the wall surface of the vacuum chamber) with this airtight seal 8 interposed, airtightness can be ensured. Even when the rotating shaft 6 is directly connected to the drive unit (directly connected to the drive unit without a drive transmission section), the airtight seal 8 interposed as described above ensures airtightness between the inside and outside of the rotating shaft 6. Furthermore, the airtight seal 8 may have a different structure than that using the O-rings 81 and 82, and the number of O-rings 81 and 82 may be increased or decreased as appropriate.

[0043] Here, the relationship between the discharge surface 11a of the cathode 11 and the rotating shaft 6 will be described. FIG. 4 is a diagram showing this relationship. As shown in this figure, the axis CL1 of the rotating shaft 6 is arranged parallel to an imaginary plane SF that includes the discharge surface 11a formed on the tip surface of the cathode 11. Furthermore, the axis CL1 of this rotating shaft 6 is significantly offset from the center line of the cathode 11, so that the multiple trigger electrodes 5a to 5c supported by the rotating shaft 6 can come into contact with the discharge surface 11a when the rotating shaft 6 is rotated about the axis CL1. With this arrangement, the rotating shaft 6 is generally outside the range facing the discharge surface 11a, while the trigger electrodes 5a to 5c, which move due to the rotation, can face the discharge surface 11a.

[0044] Furthermore, the individual trigger electrodes 5a to 5c are supported such that their respective axes CL2a to CL2c are perpendicular to the axis CL1 of the rotating shaft 6. That is, the trigger electrodes 5a to 5c are erected perpendicular to the axis CL1 of the rotating shaft 6. The individual trigger electrodes 5a to 5c can be fixed to the rotating shaft 6 by providing a through-hole and a female thread at an appropriate position on the rotating shaft 6, and then threading the base ends 51a to 51c of the other trigger electrodes 5a to 5c with the male threads. This fixing method makes it easy to individually replace the trigger electrodes 5a to 5c, but other fixing methods may also be used. As described above, the trigger electrodes 5a to 5c generate an electric spark between themselves and the cathode 11 (discharge surface 11a). Therefore, they must be electrically connected to the arc power source via the rotating shaft 6. To this end, the rotating shaft 6 must be made of a conductive material, and the trigger electrodes 5a to 5c must be electrically connected when fixed. Naturally, the electrical continuity is also achieved inside the power transmission section.

[0045] As described above, by arranging the axis CL1 of the rotating shaft 6 so that it is parallel to the imaginary plane SF that includes the discharge surface 11a, the distance from the axis CL1 of the rotating shaft 6 to the surface of the discharge surface 11a is constant. Therefore, if the three trigger electrodes 5a to 5c are all configured to be the same length, as shown in the example of Figure 4, and all of them are set under the same conditions (such as the angle at which they are erected), when the rotating shaft 6 is rotated to bring the tip portions 52a to 52c of the trigger electrodes 5a to 5c close to (in contact with) the discharge surface 11a, all of the tip portions 52a to 52c will reach the discharge surface 11a at the same time. Note that, if the lengths of the trigger electrodes 5a to 5c are changed, the angle at which they are erected must also be changed, as described below.

[0046] <Operational Mode of Trigger Electrode> Figures 5 to 8 show operational modes when the rotating shaft 6 is rotated in the arrangement of the components shown in Figure 4. Figures 7 and 8 show simplified cross-sectional views taken along line VII-VII in Figure 6.

[0047] As shown in Figure 5(a), all three trigger electrodes 5a-5c are in the same position. Assuming that these trigger electrodes 5a-5c are positioned at their farthest positions from the discharge surface 11a of the cathode 11, and that the axes CL2 of the trigger electrodes 5a-5c are perpendicular to (or rotated beyond) an imaginary plane SF that includes the discharge surface 11a, these trigger electrodes 5a-5c can be moved to the same height as (or higher than) the rotation axis 6. Therefore, when the trigger electrodes 5a-5c are positioned farther apart, no other components, including the trigger electrodes 5a-5c, are present in front of (or facing) the discharge surface 11a. Normally, at this time, plasma is generated in the vacuum chamber, and deposition processing is being performed while evaporating the cathode material. Therefore, it is preferable that no components are present in front of the discharge surface 11a.

[0048] In order to induce an arc discharge, the trigger electrodes 5 (5a to 5c) are rotated to contact the discharge surface 11a before plasma generation (or after the first-stage vapor deposition process is completed), as shown in FIG. 5(b) . At this time, the three trigger electrodes 5 (5a to 5c) are configured to be the same length, so they all approach the discharge surface 11a at approximately the same distance. Once at least one of the trigger electrodes 5 makes contact (ignites), preparations for inducing an arc discharge are complete. Then, by rotating the rotating shaft 6 again in the opposite direction and moving it away (changing to the state shown in FIG. 5(a)), at least one of the trigger electrodes 5 that had been in contact (ignited) with the discharge surface 11a is extinguished, and an arc discharge is induced.

[0049] 6(a), by rotating the rotation shaft 6 in the forward and reverse directions, the trigger electrode 5 moves from a position perpendicular to the imaginary plane SF including the discharge surface 11a to abutting the discharge surface 11a, freely retracting from and retracting in front of the discharge surface 11a. As clearly shown in this figure, the axis of the rotation shaft 6 is parallel to the imaginary plane SF including the discharge surface 11a (not on the imaginary plane). Therefore, when the tip 52 of the trigger electrode 5 is in contact with the discharge surface 11a, the axis of the trigger electrode 5 forms an appropriate angle with respect to the discharge surface 11a (imaginary plane SF). By forming this appropriate angle, the tip 52 of the trigger electrode 5 comes into contact with the surface of the discharge surface 11a, and a point contact can be achieved in a limited area.

[0050] In this embodiment, since three trigger electrodes 5 of the same length are used, it is assumed that the contact points (contact positions) x, y, and z on the surface of the discharge surface 11a are aligned in a straight line, as shown in Fig. 6(b). Each of the contact points x to z causes the cathode 11 to be worn down by arc extinction at a fixed point. However, by arranging the contact points x to z at appropriate intervals, the entire discharge surface 11a can be divided into three regions (sectioned regions) A, B, and C, and one contact point x to z can be set in each of the sectioned regions A to C (positioning one trigger electrode 5 to face each other), thereby leveling out the degree of wear of the cathode 11.

[0051] Here, the discharge surface 11a is assumed to have a circular surface, and each of the segmented regions A to C is divided into approximately equal areas. However, if the shape of the discharge surface 11a is other than circular, or by adjusting the positions of the contact points x to z, the boundaries between the segmented regions A to C can be made linear. In this case, the linear boundaries can be divided by imaginary planes perpendicular to the discharge surface 11a. By setting multiple imaginary planes at equal intervals, it is also possible to evenly divide the segmented regions A to C on the rectangular discharge surface 11a. Note that the trigger electrodes 5a to 5c are adjusted to the same length and angle and supported on the rotating shaft 6, but they may not all contact (ignite) at the same time due to installation errors, manufacturing errors of the trigger electrodes 5a to 5c, or the condition (smoothness) of the discharge surface 11a.

[0052] Therefore, as shown in FIG. 7( a), if only one (5a) of the three trigger electrodes 5a to 5c contacts the discharge surface 11a of the cathode 11, that single trigger electrode 5a will wear away and erode a portion of the cathode 11 (discharge surface 11a), forming a recess P1. In such a situation, if attempts are made to continuously contact (ignite) the single trigger electrode 5a, as shown in FIG. 7( b), the single trigger electrode 5a may no longer be able to contact (ignite) the discharge surface 11a. However, in this embodiment, because the three trigger electrodes 5a to 5c can approach the discharge surface 11a to approximately the same extent, even if the first trigger electrode 5a cannot contact (ignite), an arc discharge can be induced as long as either one of the other two trigger electrodes 5b and 5c can contact (ignite).

[0053] Similarly, even if the first trigger electrode 5a and the third trigger electrode 5c form recesses P1 and P2 at two locations on both sides as shown in Fig. 7(c), the remaining central trigger electrode 5b can make contact (ignite) as shown in Fig. 7(d). And, as shown in Fig. 8(a), recess P3 can be formed by the central trigger electrode 5b. Even if recesses P1 to P3 are formed at three locations, as shown in Fig. 8(b), if any of the three trigger electrodes 5a to 5c can make partial contact (ignite) with the surfaces of recesses P1 to P3, arc discharge can be continuously induced.

[0054] As a result of such a usage mode, even if the discharge surface 11a of the cathode 11 is worn down and recesses P1 to P3 are formed, an arc discharge can be induced as long as any of the three trigger electrodes 5a to 5c can come into contact (ignite). Therefore, it is possible to induce a continuous arc discharge with an extremely high probability.

[0055] This state is the same even when the recesses P1 to P3 expand due to wear on the cathode 11 (discharge surface 11a) caused by repeated arc extinction. That is, as shown in Figure 8(c), even when wear on the discharge surface 11a caused by each of the trigger electrodes 5a to 5c progresses and the recesses P1 to P3 expand, the erosion spreads to the periphery, and the three recesses P1 to P3 become eroded as a whole. This is because, as described above, the tip portions of the trigger electrodes 5a to 5c move with the rotation of the rotating shaft 6 (see Figure 6(a)), and each time a recess P1 to P3 is formed, the rotation angle expands to the surface of the recess P1 to P3, gradually moving from the initial contact point to the periphery.

[0056] As long as the tip of any of the trigger electrodes 5a to 5c remains in contact (to ignite) with the expanded and eroded recesses P1 to P3, arc discharge can be continuously induced using the same cathode 11. This extends the life of the material and contributes to cost reduction.

[0057] <First Modification> Next, a modification of the embodiment of the evaporation source device will be described. The first modification is shown in Figures 9 to 11. As shown in these figures, in the first modification, the trigger electrodes 5a to 5c are configured to be different lengths, and are supported by the rotating shaft 6 at different angles so that the tip portions of all of the trigger electrodes 5a to 5c can simultaneously contact the discharge surface 11a of the cathode 11 by rotation of the rotating shaft 6. The rest of the configuration is the same as in the above-mentioned embodiment.

[0058] Even when the lengths and angles of the trigger electrodes 5a to 5c are made different from one another in this way, the axes CL2a to CL2c of the respective trigger electrodes 5a to 5c are erected so as to be perpendicular to the axis CL1 of the rotating shaft 6. By arranging the axes CL2a to CL2c of the respective trigger electrodes 5a to 5c perpendicular to the axis CL1 of the rotating shaft 6 in this way, the tip portions of the respective trigger electrodes 5a to 5c move in an arc around the axis CL1 of the rotating shaft 6 as the center when the rotating shaft 6 is rotated.

[0059] Even in this modified example, as shown in FIG. 10( a), when the trigger electrodes 5 a to 5 c are placed in a state where they are farthest from the discharge surface 11 a of the cathode 11, that is, when the axis of one trigger electrode 5 b (the central one in the drawing) that serves as the reference is placed perpendicular to (or rotated beyond) the imaginary plane SF that includes the discharge surface 11 a, all of the trigger electrodes 5 a to 5 c can be retracted from the front side of (the positions facing) the discharge surface 11 a.

[0060] 10(b), by rotating the rotary shaft 6, the individual trigger electrodes 5a to 5c can be brought into contact with the discharge surface 11a at different positions in the height direction H and width direction W. At this time, by adjusting the lengths and angles of the three trigger electrodes 5a to 5c, they can be brought into similar proximity with the discharge surface 11a, and once at least one of the trigger electrodes 5 makes contact (ignites), preparations for inducing an arc discharge are complete.

[0061] 11(a), by rotating the rotation shaft 6 in the forward and reverse directions, the trigger electrodes 5a to 5c move from a state where they are retracted from the front side of the discharge surface 11a to abut against the discharge surface 11a, and can freely appear and disappear in front of the discharge surface 11a. As shown in this figure, the trigger electrodes (two electrodes on each side) 5a, 5c, which are shorter than the long trigger electrode (center electrode) 5b that serves as the reference, are angled in advance relative to the long trigger electrode 5b so as to approach the discharge surface 11a. However, by positioning the rotation shaft 6 at a position (upper in the figure) sufficiently farther from the cathode 11 (the tip end surface of the discharge surface 11a), the trigger electrodes can be retracted from the front side of the discharge surface 11a while being far away from the discharge surface 11a.

[0062] In this modified example, the three trigger electrodes 5a to 5c have different lengths (the two electrodes 5a and 5c on each side are the same), and therefore, as shown in FIG. 11(b), the contact points (contact positions) x, y, and z on the surface of the discharge surface 11a are at different positions in the height direction H and width direction W of the discharge surface 11a. In this case, the segmented regions A to C where the contact points x to z come into contact can be divided equiangularly from the center of the circular discharge surface 11a according to the number of contact points x to z, and the contact points x to z can be set approximately in the center of each of the segmented regions A to C as sector-shaped regions of the same area and number. In this case, the discharge surface 11a is worn in each of the segmented regions A to C, and the degree of wear across the entire cathode 11 can be leveled out.

[0063] Even in this modified example, it is not necessarily possible for all of the trigger electrodes 5a to 5c to contact (ignite) simultaneously and in the same state due to errors in attachment or manufacturing of the trigger electrodes 5a to 5c, or the degree of smoothness of the discharge surface 11a, etc. Therefore, any of the trigger electrodes 5a to 5c will contact (ignite) any of the contacts x to z, and preparations for inducing an arc discharge can be completed in this state.

[0064] Even in such a modified example, arc extinction at each of the contacts x to z causes the discharge surface 11 a to wear down, resulting in the formation of recesses (see FIGS. 7 and 8 ) on the surface, which then expand. However, by sequentially forming recesses at the three contacts x to z, the entire discharge surface 11 a can be utilized, and the same cathode 11 can be used for a long period of time.

[0065] <Second Modification> A second modification is shown in FIGS. 12 and 13. In the second modification, as shown in FIG. 12, two rotating shafts 6A and 6B are arranged facing each other (separated vertically) with the cathode 11 interposed therebetween, and a plurality of trigger electrodes 5a-5c and 5d-5f (three electrodes are shown in the figure) are erected on each of the rotating shafts 6A and 6B. The tip portions of the trigger electrodes 5a-5c and 5d-5f erected on the rotating shafts 6A and 6B are arranged to contact the rotating shafts 6A and 6B at positions offset from the center of the discharge surface 11a, thereby making the electrodes shorter overall. This prevents the trigger electrodes 5a-5c and 5d-5f from contacting each other when the rotating shafts 6A and 6B are rotated simultaneously. As with the first modification, the trigger electrodes 5a-5c and 5d-5f are shown with different lengths and angles, but they may also be arranged with the same length and angle.

[0066] In a modified example of the above configuration, as shown in FIG. 13(a), by rotating the rotation shafts 6A and 6B, all of the trigger electrodes 5a to 5c and 5d to 5f can be moved within a range from a state where they can be retracted from the front side of the discharge surface 11a to a state where they are in contact with the discharge surface 11a, and by configuring the trigger electrodes 5a to 5c and 5d to 5f to be short, it is possible for the trigger electrodes 5a to 5c erected on the upper rotation shaft 6A to come into contact with the upper half of the discharge surface 11a, and for the trigger electrodes 55d to 5f erected on the lower rotation shaft 6B to come into contact with the lower half of the discharge surface 11a.

[0067] In this modified example, as shown in Figure 13(b), the discharge surface 11a is divided into an upper half Hu and a lower half Hd, and the upper half Hu is then divided into three sector-shaped regions A to C, each with an equal angle from the center, and the lower half Hd is similarly divided into sector-shaped regions D to F. The trigger electrodes 5a to 5f can then contact (ignite) approximately at the center of all sectors A to F. The lengths and angles of the trigger electrodes 5a to 5c and 5d to 5f are adjusted so that the contact points x1 to z1 and x2 to z2 are points on concentric circles from the center point of the discharge surface 11a, but these can be changed as appropriate depending on how the sectors A to F are divided.

[0068] For example, only the trigger electrode 5b erected at the center of the upper rotating shaft 5A may be configured to be able to contact the center of the discharge surface 11a, and the remaining five electrodes (two on the left and right at the upper end and three at the lower end) may be configured to contact five equal fan-shaped regions.

[0069] Experimental Example 1: As in the first modified example, three trigger electrodes of different lengths and angles were erected on a rotating shaft (see FIGS. 10 and 11 ), and a 50 mm diameter graphite cathode was used. The state of wear (erosion) of the discharge surface was observed. Figure 14 shows the state observed when an arc current of 30 A was used. While photographs of the discharge surface used in the experiment are also available, the entire surface is black, making it difficult to distinguish. Therefore, Figure 14 only shows a rough outline of the observed state. The circles in the figure indicate the approximate positions of the contacts, the lightly shaded areas indicate areas that have been worn (eroded), and the darker shaded areas indicate areas with a large degree of wear (erosion depth).

[0070] Figure 14(a) shows the condition of the discharge surface after about 10 arc extinctions, and Figure 14(b) shows the condition after about 25 arc extinctions. From this figure (experimental results), it is clear that when the number of arc extinctions (number of times arc discharges were induced) was low, depressions (erosion) due to wear were observed around each contact. This indicates that arc discharges were induced by one of the multiple (three) trigger electrodes in an appropriate order. Furthermore, as the number of arc extinctions increased, the worn (eroded) area expanded, and deeper worn (eroded) areas appeared near the contacts, indicating that the degree of wear (erosion) was progressing.

[0071] From the above, it was found through experiments that when the cathode is first used, it gradually begins to wear out near each contact, and when it is almost entirely worn out, the next wear progresses further near the contact. Therefore, with continued use, it is expected that the degree of wear at the next depth will spread throughout the entire cathode, and then even deeper worn (eroded) areas will appear. In this way, the degree of wear gradually spreads from the contact to its periphery, and as the degree of wear progresses, the same degree of wear will spread throughout the entire cathode. As a result, even if the same cathode is used continuously, it will not affect the induction of arc discharge and the life of the cathode can be extended.

[0072] <Experimental Example 2> In another experiment, the three trigger electrodes were all the same length (see Figures 4 to 6), and a cathode made of graphite with a diameter of 50 mm was used. The state of wear (erosion) of the discharge surface was observed. The state at that time is shown in Figure 15. Note that Figure 15(a) shows the state of the discharge surface when the arc had been extinguished about 10 times, and Figure 15(b) shows the state when the arc had been extinguished about 20 times. The other illustration methods are the same as those in Experimental Example 1.

[0073] As is clear from this experiment, when the number of extinguishing cycles is low, wear begins gradually from the vicinity of each contact, and as the number of extinguishing cycles increases, the entire contact becomes worn. Although the number of cycles thereafter has not been observed, it is believed that continued use will result in further wear near the contacts, forming the next deep depression.

[0074] <Comparative Experiment> For comparison with the above experimental example, the state of wear when an arc discharge was induced by a single trigger electrode was observed. The state is shown in Fig. 16. Fig. 16(a) shows the state of the discharge surface when the arc was extinguished about 2 to 3 times, and Fig. 16(b) shows the state when the arc was extinguished about 10 times. The other methods of illustration are the same as those in Experimental Example 1.

[0075] As is clear from the results of the above comparative experiments, wear begins at the periphery of one contact point, and as the number of times the arc is extinguished increases, the range of wear expands to the periphery. However, even if the number of times the arc is extinguished increases, the range of wear does not expand to the entire discharge surface. From the results of the observations, it was not possible to identify any deeply worn (eroded) areas, but it is expected that the periphery of one contact point will subsequently become significantly eroded. Therefore, when an arc discharge is triggered by a single trigger electrode, it is possible that wear progresses in one area, making contact (ignition) difficult, and that erosion in a biased area will progress significantly, shortening the life of the cathode.

[0076] <Summary> As the contents of the embodiments and experimental examples of the present invention are as described above, in the embodiments, etc., relating to the evaporation source device for vacuum arc deposition, arc discharge can be generated simply by rotating the rotating shaft, and as long as there is a drive device for this, there is no need to use any other complicated mechanism. Moreover, since the arc can be extinguished at multiple locations on the discharge surface of the cathode by using multiple trigger electrodes (three or six in the above example), significant local wear at some contact points can be avoided. Even if one contact point is significantly worn, arc discharge can be generated by contact with another trigger electrode, which enables long-term use of the cathode and contributes to reducing material costs.

[0077] On the other hand, in the embodiment of the vacuum arc deposition apparatus, since the evaporation source device for vacuum arc deposition described above is used, arc discharge can be easily induced in the entire apparatus with only a few additional components, thereby reducing the cost of the apparatus. Furthermore, the evaporation source device for vacuum arc deposition reduces the possibility of arc discharge not occurring and allows the cathode to be used for a long period of time. Furthermore, since the same cathode can be used for a long period of time, the running cost of the entire apparatus is reduced.

[0078] The embodiments and modifications of the present invention have been described above, but these embodiments are merely examples of the present invention, and the present invention is not intended to be limited to the above-described embodiments, etc. Therefore, some of the components described in the above-described embodiments, etc. may be modified, or other components may be added.

[0079] For example, although only one (in the embodiment and the first modified example) or two (in the second modified example) rotation shafts 6, 6A, and 6B are described, more rotation shafts may be added, and the number of trigger electrodes 5 may be increased accordingly.

[0080] Furthermore, although the cathode 11 having a basically circular surface has been described as an example, if the shape of the cathode 11 is not circular, the desired trigger electrode 5 can be arranged by appropriately setting the divided areas A to H.

[0081] Furthermore, the shapes of the individual trigger electrodes 5a to 5c are not specified, and although the figures show them as being made up of straight rod-like members, within the spirit of the present invention, the trigger electrodes 5a to 5c may be curved or bent. The essential point is that the tip portions 52a, 52b, and 52c of the electrodes 5a to 5c are capable of contacting predetermined positions on the tip surface (discharge surface 11a) of the cathode 11.

[0082] From this viewpoint, only the tip portions 52a to 52c of the trigger electrodes 5a to 5c may be bent or curved, or other members may be attached to them. Examples of such cases are shown in Figures 17 and 18, but the present invention is not limited to these.

[0083] For example, as shown in FIG. 17( a), there is a configuration in which the vicinity of the tip portions 52a to 52c is bent in a substantially V-shape. In such a configuration, as shown in FIG. 7( b), the bent portion of the substantially V-shaped valley can be made to contact the cathode 11 (discharge surface 11a). With such a configuration, first, the contact position with the discharge surface 11a can be easily adjusted by adjusting the bending position or bending angle. Second, by bending the bent portion in advance, a damping effect can be expected by allowing deformation at the bending position. Third, the bending angle of the bent portion (or curving it into an arc, for example) can expand the contact area with the discharge surface 11a. Note that if a damping effect can be exerted, the contact pressure upon contact with the cathode 11 (discharge surface 11a) can be alleviated. By alleviating the contact pressure, the load on the rotating shaft 6 can be reduced and wear on the cathode 11 (discharge surface 11a) due to triggering (ignition) can be reduced.

[0084] When the tip portions 52a to 52c of the trigger electrodes 5a to 5c are deformed for the above-mentioned purposes, various shapes are possible, as shown in FIG. 18 . For example, to expand the contact area with the discharge surface 11a, the tip portions 52a to 52c can be spherical (or spherical contacts can be attached) as shown in FIG. 18( a). Instead of spherical tip portions 52a to 52c, the vicinity of the tip portions 52a to 52c can be curved in an arc as shown in FIG. 18( b). Furthermore, to achieve a damping effect, the tip portions 52a to 52c can be spring-shaped as shown in FIG. 18( c). In the case of a spring shape, multiple annular portions can be formed, which can increase the number of contact positions.

[0085] The tip portions 52a-52c of these trigger electrodes 5a-5c do not need to be all the same shape (three in the figure); only one of them may be deformed. For example, as shown in FIG. 18(d), a configuration in which the vicinity of a single central tip portion 52b is bent for the purpose of adjusting the contact position with the discharge surface 11a may be adopted. In FIG. 18(d), only one portion is bent for the purpose of adjusting the contact position, but as shown in FIG. 18(e), a configuration in which two or more portions are bent for the purposes of adjusting the contact position and providing a damping effect may also be adopted. Furthermore, as shown in FIG. 18(f), one or more of the tip portions 52b may be spring-shaped. If it is difficult to adjust the contact position, a spring-shaped configuration may be adopted in advance to allow for deformation.

[0086] REFERENCE SIGNS LIST 1 Plasma generating means 2 Plasma duct 3 Film forming chamber (vacuum chamber) 4 Insulated lead-in terminal 5, 5a, 5b, 5c, 5d, 5e, 5f Trigger electrode 6, 6A, 6B Rotating shaft 6 7 Driving device 8 Airtight seal 9 Trigger control mechanism 11 Cathode 11 11a Discharge surface 12 Anode 13 Arc power supply 14 Trigger current limiting resistor 31 Workpiece holding means 51a, 51b, 51c Base end of trigger electrode 52a, 52b, 52c Tip portion of trigger electrode 60 Power transmission section 61 Drive shaft 62, 65 Sleeve 63, 64 Bevel gear A, B, C, D, E, F Sectional area CL1 Axis of rotating shaft CL2a, CL2b, CL2c Axis of trigger electrode SF Virtual plane P1, P2, P3 Recess x, y, z, x1, y1, z1, x2, y2, z2 Contact

Claims

1. A vacuum arc evaporation device for vapor deposition processing by generating plasma through arc discharge between a cathode and an anode connected via a power source in a vacuum, and evaporating the cathode material that constitutes the cathode, comprising: a cathode that is an evaporation source; and a plurality of trigger electrodes arranged to induce arc discharge and facing the discharge surface of the cathode; the plurality of trigger electrodes are supported on the same rotating shaft connected to a single power source and a single current limiting resistor; rotation of the rotating shaft enables at least one of the tips of the plurality of trigger electrodes to come into contact with the discharge surface of the cathode; and when the discharge surface is divided into any number of regions according to the number of trigger electrodes, the device is arranged so that one trigger electrode faces each of the divided regions.

2. An evaporation source device for vacuum arc evaporation as described in claim 1, wherein the rotation shaft is rotatable about an axis parallel to an imaginary plane including the discharge surface, the plurality of trigger electrodes are provided to protrude from the rotation shaft, and the gaps between the tips of the plurality of trigger electrodes as they approach the discharge surface are adjusted to be approximately uniform by the rotation of the rotation shaft.

3. An evaporation source device for vacuum arc evaporation according to claim 2, wherein the divided areas are sector-shaped areas divided from the center point of a circular discharge surface at equal angles equal to the number of the plurality of trigger electrodes.

4. An evaporation source device for vacuum arc evaporation as described in claim 3, wherein the trigger electrodes are erected in a direction perpendicular to the axis of the rotation shaft, and the length and angle of each trigger electrode are adjusted so that they can individually contact approximately the center of each divided area.

5. An evaporation source device for vacuum arc evaporation according to claim 2, wherein the divided areas are areas divided equidistantly by imaginary planes perpendicular to the axis of the rotation shaft with respect to a discharge surface of any shape.

6. An evaporation source device for vacuum arc evaporation as described in claim 5, wherein the trigger electrodes are erected in a direction perpendicular to the axis of the rotation shaft, and the lengths and angles of the individual trigger electrodes are adjusted to be approximately the same so that they can individually contact approximately the centers of the divided regions.

7. An evaporation source device for vacuum arc evaporation according to any one of claims 1 to 6, wherein the rotation shafts are provided at two locations facing each other with the discharge surface of the cathode at the center, and approximately half of the number of the plurality of trigger electrodes are provided separately on the two rotation shafts.

8. An evaporation source device for vacuum arc evaporation as described in claim 7, wherein the divided area is divided into halves on the side where the two rotation axes are provided by a straight line including the center point of the discharge surface, and the area close to the rotation axes is divided according to the number of trigger electrodes provided on each rotation axis.

9. A vacuum arc evaporation apparatus comprising the evaporation source device according to any one of claims 1 to 6.

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