JP5429802B2 - Vacuum arc evaporation system - Google Patents

Description

  The present invention relates to a vacuum arc vapor deposition apparatus, and more particularly to a vacuum arc vapor deposition apparatus used for forming a hard film.

  It is known to use FCA (Filtered Cathodic Arc) method, which is a film formation method using vacuum arc discharge as a plasma source to form DLC (Diamond Like Carbon) film, which is a kind of thin hard film. (For example, see Patent Documents 2 and 3). In the FCA method, the cathode is evaporated by vacuum arc discharge to generate plasma containing the cathode material. A DLC film formed by drawing ions in plasma generated using a plasma source by vacuum arc discharge into a substrate by a negative bias or the like has a high ratio of SP3 component to SP2 component. For this reason, a hard and durable DLC film is obtained.

  However, the FCA method has a problem that there are many macro particles. This is not only a plasma containing the cathode material but also a drop that is a neutral droplet in which the cathode material is liquefied when the arc discharge is performed by contacting the vacuum arc evaporation source as the cathode and anode with the vacuum arc evaporation source. This is because lets (hereinafter referred to as macro particles) are also generated and scattered while solidifying to the outside of the cathode surface, and the scattered macro particles repeatedly collide with the inner wall of the curved plasma transport tube and adhere to the substrate surface.

  When the macro particles adhere to the surface of the substrate for forming a film, not only the smoothness of the film surface is impaired, but also the macro particles adhering later peel off from the surface of the substrate, and the attached DLC film itself also peels off. become. Therefore, it is not preferable to form such a film as a surface film on a mold or the like for molding a resin or rubber.

  As a method for preventing macroparticles from adhering to the substrate surface, a vacuum arc vapor deposition apparatus in which particle removal means is provided in a plasma transport tube is known.

Patent Document 1 describes disposing a porous member on the inner wall of a plasma transport tube. Patent Document 2 describes that a plate-like filter member provided with a hole penetrating from the front surface to the back surface is provided on the inner wall of the plasma transport tube. Patent Document 3 describes that a thin plate, which is a flat ring member, is connected to the inner wall of a plasma transport tube with a wire to form a baffle structure. The thin plates should be arranged side by side, with adjacent thin plates being parallel to each other, joined together by a total of eight wires at four positions of 90 ° in the circumferential direction and outer peripheral portion without the thin plate in the circumferential direction. Is described. Japanese Patent Application Laid-Open No. H10-228561 describes that an integrated structure particle removing means is formed by welding thin plates, which are frustoconical ring members, to the inner wall of a plasma transport tube.

JP 2002-105628 A (see FIG. 1) JP 2008-291326 A (see FIG. 1) JP 2004-244667 A (see FIG. 11) US Pat. No. 6,031,239 (see FIG. 11)

  However, in the particle removing means of Patent Document 1, when the porous member is fixed in the plasma transport tube, it may hang down due to its own weight.

  In the particle removing means of Patent Document 2, since the filter plate is provided in the straight part of the plasma transport tube, the removal of macro particles is not sufficient. Further, there is a problem that the mesh hole size of the filter plate is small and is easily clogged and cannot be used for a long time.

  The particle blocking means of Patent Document 3 has a complicated structure because a large number of flat ring members are connected by wires, and the manufacturing cost is high.

  Also in the structure of Patent Document 4, since the frustoconical ring member is connected, the welding work is increased, and the manufacturing cost is increased. Further, the macro particle removing means of Patent Document 4 has a problem that the amount of macro particles adhering to the substrate is increased when the attachment direction is wrongly attached.

  In Patent Documents 2 and 3, since a plate-shaped donut-shaped member having a hole is used, there is a problem that a cross-sectional area of a passage for transporting plasma is reduced and plasma contributing to film formation is reduced. Further, in Patent Documents 2, 3, and 4, when the outer diameter of the particle removing means is approximately the same as the inner diameter of the plasma transport tube, it is attached to the inner wall of the curved plasma transport tube. There was a problem that it was difficult to attach and remove during maintenance due to frictional resistance.

  An object of the present invention is to provide a device that can produce a smooth and highly adhesive thin film free from macro particles or the like in the film, and that is low in cost and excellent in maintainability.

The vacuum arc deposition apparatus of the present invention comprises a vacuum arc evaporation source that generates a plasma containing a cathode material by evaporating a cathode by vacuum arc discharge, a vacuum chamber that contains a substrate and is evacuated, and a magnetic field forming means outside. In the thin film forming apparatus provided with the curved plasma transport pipe , a particle removing means having a shape in which a plate-like member made of a porous member and a core material is spirally arranged on the inner wall of the plasma transport means. It was established .

  The apparatus of the present invention can effectively remove the macro particles in the plasma generated by the vacuum arc evaporation source. Therefore, a DLC film having good adhesion is formed in which there is no mixing of macro particles in the DLC film formed on the surface of the substrate, and there is no peeling of the DLC film due to peeling of the mixed macro particles from the surface of the substrate. be able to.

  Further, the macro particle removing means according to the present invention facilitates fixation to the inner wall of the curved plasma transport tube, shortening maintenance work such as attachment and removal, and shortening the exposure time of the apparatus to the atmosphere. Furthermore, since the structure is simpler than the baffle in which the conventional thin ring is connected, it can be manufactured at low cost and the running cost can be reduced.

It is a schematic diagram which shows the structure of the vacuum arc vapor deposition apparatus which concerns on this invention. It is a schematic diagram which shows one aspect | mode of the particle removal means of this invention. It is a schematic diagram which shows the other example of the particle removal means of this invention. It is a figure which shows the example of the metal mold | die as a base | substrate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiments.

First, with reference to FIG. 1, the one aspect | mode of the vacuum arc vapor deposition apparatus of this invention is demonstrated.
FIG. 1 is a schematic view showing an embodiment of the vacuum arc vapor deposition apparatus of the present invention. The vacuum arc deposition apparatus includes a vacuum chamber 1 that is evacuated by an unillustrated evacuation apparatus. In the vacuum chamber 1, a holder 10 that holds a substrate 2 to be formed is disposed. The holder 10 is supported by a rotating shaft and is rotated by the drive unit 8. A bias power source is connected to the holder 10 and the base 2 held by the holder 10, and a bias voltage is applied.

  The plasma transport tube 4 has a bent shape. On the outer periphery of the curved plasma transport tube 4, a deflection magnetic field forming means comprising a magnetic coil 3 is provided. As the magnetic coil 3, for example, a coil wound with a polyamideimide-coated copper wire is used. Further, a macro particle removing means 5 is provided on the inner wall of the plasma transport tube 4.

  A vacuum arc evaporation source 7 is connected to one end of the plasma transport tube. One end of the plasma transport tube 4 is connected to a part of the opening of the vacuum chamber 1 so as to face the base 2 on the holder 10. By evacuating the vacuum chamber 1, the curved plasma transport tube 4 is also evacuated.

  The vacuum arc evaporation source 7 has a columnar cathode 6 made of graphite (carbon) disposed in the vacuum arc evaporation source 7 as a target. A power source E is connected to the cathode 6. The vacuum arc evaporation source 7 contacts the surface of the cathode 6 with a striker 11 between the cathode 6 and the vacuum arc evaporation source 7 also serving as an anode, and dissolves the surface of the cathode 6 by vacuum arc discharge to evaporate the cathode material. The cathode material evaporated from the cathode surface is ionized. On the other hand, the plasma generated by the arc discharge transports only electrons and cathode material ions, which are charged particles in the plasma, by the magnetic field generated by the electromagnetic coil 3 wound around the outer periphery of the plasma transport tube 4. Therefore, the cathode material ions reach the surface of the base 2.

  The plasma is induced to the substrate 2 disposed in the vacuum chamber 1 using the plasma transport tube 4 to form a DLC film that is a hard film on the surface of the substrate 2. In this case, since graphite (carbon) is used for the cathode 6, a DLC film having a high sp3 component ratio can be obtained.

  Further, in the present invention, since the particle removing means 5 is provided in the plasma transport tube, the macro particles in the plasma generated by the vacuum arc evaporation source can be effectively removed. Therefore, a DLC film having good adhesion is formed in which there is no mixing of macro particles in the DLC film formed on the surface of the substrate, and there is no peeling of the DLC film due to peeling of the mixed macro particles from the surface of the substrate. be able to.

  Next, an embodiment of the macro particle removing means of the present invention will be described with reference to FIG. FIG. 2B is a schematic view schematically showing one aspect of the macro particle removing means of the present invention. Moreover, Fig.2 (a) is a schematic diagram which shows the base member which forms the macro particle removal means of this invention.

  The macro particle removing means 23 of this aspect has a shape in which the long base member 20 is spirally wound. The base member 20 is composed of a porous member and a wire-like core material. The wire-like core material 22 is disposed so as to be skewered in the longitudinal direction of the porous member 21. As the porous member 21, it is preferable to use a metallic porous member. Metallic wool can be used as the metallic porous member. As the core material 22, it is preferable to use a metallic wire-like core material, and a wire having a spring property can be used. Stainless steel can be used as the wire. As the metal wool, stainless steel can be used, but not only stainless steel but also copper or iron coated by plating or the like may be used.

  In addition, the metal wool is not limited to those composed of metal fibers or the like, regardless of the production method, which is configured to have a slender metal foil in the form of wool and have porosity and gas permeability, Including those that result in a wool-like configuration.

  If the macro particle removing means of the present invention is used, the kinetic energy of the macro particles is absorbed by the wooly and fibrous members, and the macro particles are reflected again and do not scatter. Even if it is reflected, since the macro particle removing means of the present invention is formed of a porous member, it reattaches to the inside of the wool or fibrous member, so that the macro particle trapping effect is maintained. Furthermore, the surface area of the porous member formed from a wool-like or fibrous member is also large, and it is possible to maintain a long-term effect.

  The macro particle removing means according to the present embodiment spirals a long base member 30 arranged so that a metallic wire-like core material 22 having a spring property is inserted into a porous member 21 such as metal wool. Since it is formed in a shape, it has stretchability in the length direction and the radial direction. For this reason, it is inserted with a spring force that is smaller than the diameter of the transport pipe, and expands inside, so that it can be easily fixed without a fixing bracket or the like. Further, the inner wall of the curved portion of the curved plasma transport tube 4 can be covered without a gap.

  Furthermore, since the base member 20 of the microparticle means of this embodiment has a double structure consisting of the member 21 formed of metal wool and the core material 22, the metal wool-like structure is formed on the inner wall of the curved plasma transport tube 4. The member 21 made of a material can be brought into close contact.

  With reference to FIG. 3, another aspect of the macro particle removing means of the present invention will be described. FIG. 3B is a schematic diagram schematically showing another aspect of the macro particle generating means of the present invention. FIG. 3A is a schematic view showing a base member that forms the macro particle removing means of the present invention.

The macro particle removing means of this aspect is an example formed by rounding the plate-like base member 30 into a cylindrical shape. At this time, it is preferable to round the base member 30 so that both ends rounded the base member 30 have a gap of about 10 mm to 30 mm. When the macro particle removing means having such a configuration is inserted into the plasma transport tube, the macro particle removing means is inserted into a cylindrical shape having a small diameter so that the gap is eliminated (overlapped). When fixing in the plasma transport tube, it is fixed so that the gap is 0 mm or overlaps about 10 mm to 30 mm.

  The base member 30 is arranged so that a metallic porous core 31 is skewered vertically and horizontally by a metallic wire-like core material 32. The macro particle removing means of this aspect is formed by making the base member 30 formed using a springy core material into a cylindrical shape, so that it is smaller than the transport pipe diameter at the time of insertion by the spring force. It can be inserted and expanded inside, and can be easily fixed without fixing hardware. Further, since the base member 30 of the macro particle removing means of this embodiment is formed of the porous member 31 made of metal wool and the spring-like wire-like core material 32, the inner wall of the curved plasma transport tube 4 It is possible to closely contact the metal wool 31.

  According to the vacuum arc vapor deposition apparatus of the present invention, the DLC thin film can be formed on the molding portion on the resin or rubber molding die 51 as shown in FIG.

  Furthermore, the DLC film formed according to the present invention is not limited to a hard film of a resin or rubber molding die. For example, the present invention may be used when forming a functional protective film for machine parts, automobile parts, tools, etc., a protective film for a magnetic recording medium, and a DLC film as a protective film for a magnetic head. Further, the arc vapor deposition apparatus of the present invention may be used when forming a DLC film on a part of a semiconductor element, an electronic component element or the like.

DESCRIPTION OF SYMBOLS 1 Vacuum chamber 2 Base | substrate 3 Coil 4 Plasma transport tube 5 Macro particle removal means 6 Cathode 7 Vacuum arc evaporation source 8 Drive part 9 Bias power supply 20 Base member 21 Metal wool 22 Wire-like core material 23 Macro particle removal means 30 Base member 31 Metal Wool 32 Wire core 33 Macro particle removing means 51 Mold 52 Hard coating

Claims (1)

A vacuum arc evaporation source for generating a plasma containing a cathode material by evaporating a cathode by vacuum arc discharge, a vacuum chamber containing a substrate and evacuated, and a curved plasma transport tube having a magnetic field forming means outside In the thin film forming apparatus,
A vacuum arc deposition apparatus characterized in that a particle removing means having a shape obtained by bending a plate-like member made of a porous member and a core material into a spiral shape is disposed on the inner wall of the plasma transport means.