Abstract: Disclosed are an apparatus and a method to synthesize powders typed diamond with the size between several tens nm to several ?m in diameter using conventional CVD processes for deposition of diamond films. Gas phase nucleation has been induced on the boundary of plasmas, and as a result the spherical diamond powders accumulated have been obtained on circumferences of the normal substrate. With a modification of a substrate structure, a large area accumulation of the diamond powders of around 100 mm in diameter has been accomplished.

Abstract: A diamond film depositing apparatus and method are disclosed in which a uniform and large plasma is formed on a substrate having a diameter of larger than 100 mm without using a heated filament cathode, without applying a magnetic field thereto, and without using a ballast resistance. The thusly formed plasma is maintained stably for a long time, so that a diamond thick film having a diameter of larger than 4 inches and a thickness of over hundreds of &mgr;m can be deposited on a flat or curved substrate and also on a Si wafer.

Abstract: Disclosed are an apparatus and a method to synthesize powders typed diamond with the size between several tens nm to several &mgr;m in diameter using conventional CVD processes for deposition of diamond films. Gas phase nucleation has been induced on the boundary of plasmas, and as a result the spherical diamond powders accumulated have been obtained on circumferences of the normal substrate. With a modification of a substrate structure, a large area accumulation of the diamond powders of around 100 mm in diameter has been accomplished.

Abstract: The present invention relates to a diamond film synthesizing apparatus, and in particular to an apparatus for increasing the deposition area to several inches in diameter by using multiple cathodes (Multi-cathode DC PACVD). In the multi-cathode DC PACVD apparatus according to the present invention, the basic array of the cathodes is determined so that the uniformity of diamond films on a deposition area is maximized. A seven-cathode structure, in which six cathodes are radially arranged at the same distance of 43 mm surrounding one central cathode, in which a basic unit of the array is regular triangle, is designed for depositing uniform diamond films on a 4″ substrate. Here, the shape of six edge cathodes is rod of which the lateral face is joined to the connecting rod, so that non-uniformity of temperature in the edge cathode is minimized and then the reliability of the apparatus is much enhanced.

Abstract: A diamond film depositing apparatus and method are disclosed in which a uniform and large plasma is formed on a substrate having a diameter of larger than 100 mm without using a heated filament cathode, without applying a magnetic field thereto, and without using a ballast resistance. The thusly formed plasma is maintained stably for a long time, so that a diamond thick film having a diameter of larger than 4 inches and a thickness of over hundreds of &mgr;m can be deposited on a flat or curved substrate and also on a Si wafer.

Abstract: In order to provide an excellent toughness and a sufficient adhesive force without any limit in the content of other carbides in the substrate material and Co and in the size of the cemented carbides grains, the present invention provides a diamond film coated cutting tool, comprising a surface layer which cemented carbide grains are grown abnormally on the cemented carbide substrate, and a diamond film formed on the surface layer, and also a method for manufacturing a diamond film coated cutting tool, comprising the steps of heat-treating a surface of a cemented carbide substrate under a decarburizing atmosphere until the surface changes to a &eegr; phase, heat-treating the surface-decarburized cemented carbide substrate under a carburized atmosphere, depositing a diamond film on the carburized surface of the cemented carbide substrate.

Abstract: A diamond film depositing apparatus and method are disclosed in which a uniform and large plasma is formed on a substrate having a diameter of larger than 100 mm without using a heated filament cathode, without applying a magnetic field thereto, and without using a ballast resistance. The thusly formed plasma is maintained stably for a long time, so that a diamond thick film having a diameter of larger than 4 inches and a thickness of over hundreds of &mgr;m can be deposited on a flat or curved substrate and also on a Si wafer.

Abstract: In order to provide an excellent toughness and a sufficient adhesive force without any limit in the content of other carbides in the substrate material and Co and in the size of the cemented carbides grains, the present invention provides a diamond film coated cutting tool, comprising a surface layer which cemented carbide grains are grown abnormally on the cemented carbide substrate, and a diamond film formed on the surface layer, and also a method for manufacturing a diamond film coated cutting tool, comprising the steps of heat-treating a surface of a cemented carbide substrate under a decarburizing atmosphere until the surface changes to a &eegr; phase, heat-treating the surface-decarburized cemented carbide substrate under a carburized atmosphere, depositing a diamond film on the carburized surface of the cemented carbide substrate.

Abstract: A diamond film depositing apparatus and method are disclosed in which a uniform and large plasma is formed on a substrate having a diameter of larger than 100 mm without using a heated filament cathode, without applying a magnetic field thereto, and without using a ballast resistance. The thusly formed plasma is maintained stably for a long time, so that a diamond thick film having a diameter of larger than 4 inches and a thickness of over hundreds of &mgr;m can be deposited on a flat or curved substrate and also on a Si wafer.

Abstract: A method of synthesizing an even free-standing diamond film without growth cracks is disclosed. The intrinsic tensile stress of a diamond film is compensated by an artificial compressive stress with a step down control of the deposition temperature during deposition. After a diamond film is deposited with a predetermined thickness at a deposition temperature, the deposition temperature is decreased in multiple steps during the deposition. The bending of the diamond wafer is minimized by using a tungsten substrate with higher elastic modulus than molybdenum.

Abstract: A head drum is coated with double films, each having different characteristics, by forming a first diamond-like hard carbon film of high degree of hardness and then forming a second diamond-like hard carbon film of a lower degree of hardness thereon. The degree of hardness of the second film is lower than that of the first film. The double coating is performed by means of a synthesizing apparatus which comprises a reactor consisting of a power supply electrode, a workpiece support and and an annular ground electrode spaced from the stacked head drums by a predetermined distance.

Abstract: A high curvature diamond field emitter tip fabrication method includes forming on a substrate a diamond film composed of square (100) phase-oriented facets and (111) phase-oriented facets distributed thereabout and columnar diamond particles having defect density differences between the diamond formed beneath the (100) and (111) diamond growth facets, and etching the diamond film using a oxygen-containing gas plasma. Further, the method includes forming on a substrate a diamond film composed of square (100) facets and (111) facets distributed thereabout and columnar diamond particles having defect density differences between the diamond formed beneath the (100) and (111) diamond growth facets, forming a supporting film on the diamond film, removing the substrate therefrom, and etching the diamond film using an oxygen-containing gas plasma after any one of the previously described steps.

Abstract: An aluminum head drum for use in a video cassette recorder is coated with a protective layer comprising diamond-like carbon. The protective layer of diamond-like carbon is obtained using a plasma-enhanced chemical vapor deposition method and has a thickness ranging from 0.3 .mu.m to 2.0 .mu.m. The protective layer has a varying mechanical hardness, wherein the mechanical hardness has a maximum value at a region of the protective layer coming in contact with the aluminum head drum, decreases smoothly and continuously and reaches an minimum value at a region of the protective layer coming in contact with atmosphere. Micro-Vicker's hardness of the region of the protective layers coming in contact with a video tape is 1.5-2.0 times that of the magnetic substance constituting the video tape.

Abstract: A head drum is coated with double films, each having different characteristics, by forming a first diamond-like hard carbon film of high degree of hardness and then forming a second diamond-like hard carbon film of a lower degree of hardness thereon. The degree of hardness of the second film is lower than that of the first film. The double coating is performed by means of a synthesizing apparatus which comprises a reactor consisting of a power supply electrode, a workpiece support and an annular ground electrode spaced from the stacked head drums by a predetermined distance.

Abstract: A fabrication method for a diamond-coated cemented carbide cutting tool includes electrolytically etching the surface of a cemented carbide cutting tool with a NaOH or KOH aqueous solution or chemically etching the surface of the cemented carbide cutting tool with a KMnO.sub.4 +KOH aqueous solution, and depositing a diamond film on the cemented carbide cutting tool. A stronger etching effect than by using a Murakami solution can be achieved, and no poisonous material is included in the etchant. In addition, disposal of the waste etchant is made simpler, and the adhesion between the diamond film coating and the cemented carbide cutting tool can be strengthened.

Abstract: A head drum is coated with double films, each having different characteristics, by forming a first diamond-like hard carbon film of high degree of hardness and then forming a second diamond-like hard carbon film of a lower degree of hardness thereon. The degree of hardness of the second film is lower than that of the first film. The double coating is performed by means of a synthesizing apparatus which comprises a reactor consisting of a power supply electrode, a workpiece support and an annular ground electrode spaced from the stacked head drums by a predetermined distance.

Abstract: An improved diamond film synthesizing apparatus and a method thereof using a direct current glow discharge plasma enhanced chemical vapor deposition advantageously providing a plurality of cathodes for forming a relatively large plasma size, which includes a reactor having an upper wall and a bottom wall; a plurality of spaced apart cathode holders half inserted into the upper wall of the reactor, arranged in a triangle when looking dowawardly over the head of the reactor; a plurality of cathode connecting rods, each of which is threadly connected to the cathode holders inside the reactor, respectively; a plurality of cathodes, each of which is threadly connected to the cathode connecting rods, respectively; an anode half inserted into the bottom wall of the reactor and having a substrate attached on the top thereof, whereby all the cathodes and the anodes are spaced apart inside the reactor by a predetermined distance; and a gas supplier connected to one side wall of the reactor having a circular gas supplyi

Abstract: An apparatus and method for simultaneously coating a large number of cylindrical substrates employs plural pairs of power electrode and the ground electrodes connected with an independent power sources in order to promote the uniform coating of the substrates. The apparatus uses a high-frequency plasma chemical deposition method and comprises a power supply system, a gas supply system, and a vacuum system. These systems are operatively connected to a reactor. The reactor comprises plural electrodes, workpiece supports, insulators, annular ground electrodes, gas outlets and gas supply means. The method comprises a step for stacking the substrates or the workpiece supports and combining them with the electrodes, a step for introducing gas to the reactor, a step for applying power to the power electrodes, and a step or maintaining the pressure in the reactor constant.

Abstract: The present invention relates to a method and an apparatus for testing the surface properties, i.e., abrasion property, friction coefficient, lubrication property, etc., of cylindrical object, e.g., VTR head drums, photocopier or laser printer drums, sewing machine spindles, fishing rod reels, etc. The apparatus of the present invention provides: a mounting means upon which a specimen of cylindrical object and a relative specimen of a flexible material is mounted and which can measure tension; a motor control unit which is connected to said mounting means so as to enable control; an amplifier electrically connected to a tension meter of said mounting means; and a computer, electrically connected to said amplifier and said motor control unit, which has been programmed to record at timed intervals the motor rotation speed and the estimated tension values, and organizes and controls all of the above said parts.