摘要:
A plasma reactor for diamond synthesis includes a microwave generator, a waveguide connected to the microwave generator, an antenna disposed within the waveguide to direct the microwaves propagated along the waveguide toward the interior of a reaction chamber, a microwave window provided above the upper wall of the waveguide, a reaction chamber defined by (a) a cylindrical bottom member hermetically joined to the microwave window and the waveguide, (b) a reaction gas inlet port and a gas outlet port in the side wall thereof, and (c) a substrate holder disposed within the reaction chamber in facing opposition to the microwave window so as to be moved toward and away from the microwave window to adjust the distance between the microwave window and the substrate holder to generate a desired microwave resonance mode. A plasma is produced only in the central portion of the reaction chamber, so that the etching of the microwave window and the resulting contamination of the diamond film by impurities produced by etching the microwave window are prevented. The plasma reactor for diamond synthesis is capable of forming a high-quality diamond film on a large surface of a substrate at a high growth rate in a range of 1 to 2 .mu.m/hr.
摘要:
Described is an etching method of a diamond film which comprises providing a diamond film in an atmosphere of a gas containing at least oxygen and/or hydrogen and subjecting the diamond film to an irradiation of an electron beam generated by direct current discharge through a pattern of a mask. In this condition, when the diamond film is contacted with the plasma produced by the electron beam in the atmosphere, the unmasked areas are irradiated by the electron beam, and converted to graphite. The graphite is more readily etched by the plasma, so that the diamond film can be etched at a high rate. The etching through a mask ensures a fine etched pattern of the diamond film. In addition, a diamond film with a large area can be etched by this method.
摘要:
A schottky diode manufacturing process employing diamond film comprises forming a B-doped p-type polycrystalline diamond film on a low-resistance p-type Si substrate by CVD using a source gas consisting of CH.sub.4, H.sub.2 and B.sub.2 H.sub.6, forming an ohmic contact on the back of the p-type Si substrate, and forming a metal electrode of Al, Pt Au, Ti or W on the B-doped p-type polycrystalline diamond film. The B/C concentration ratio of the source gas is greater than 0.01 ppm and less than 20 ppm.
摘要:
A method is related to grow monocrystalline diamond films by chemical vapor deposition on large area at low cost. The substrate materials are either bulk single crystals of Pt or its alloys, or thin films of those materials deposited on suitable supporting materials. The surfaces of those substrates must be either (111) or (001), or must have domain structures consisting of (111) or (001) crystal surfaces. Those surfaces can be inclined within .+-.10 degree angles from (111) or (001). In order to increase the nucleation density of diamond, the substrate surface can be scratched by buff and/or ultrasonic polishing, or carbon implanted. Monocrystalline diamond films can be grown even though the substrate surfaces have been roughened. Plasma cleaning of substrate surfaces and annealing of Pt or its alloy films are effective in growing high quality monocrystalline diamond films.
摘要:
A method and apparatus for contructing diamond semiconductor structures made of polycrystalline diamond thin films is disclosed. The use of a polycrystalline diamond deposition on a substrate material provides an advantage that any substrate material may be used and the ability to use polycrystalline diamond as a material is brought about through the use of an undoped diamond layer acting as an insulating layer which is formed on a boron-doped layer. Because of the structure, ion implantation can be employed to reduce the ohmic contact resistance. The ion implantation also provides that the entire structure can be made using a deep implant to form a channel layer which allows the insulating gate structure to be formed as an integral part of the device. The buried channel can be doped through the use of several implantation steps through the insulating undoped layer. As a result, the process and device is able to provide active polycrystallline diamond devices which have excellent resistance and reverse voltage characteristics while having an increased temperature capacity and increased range of operational environmental conditions when contrasted with the silicon technology. Furthermore with the disclosed process and devices, there is no requirement for a single crystal diamond substrate.
摘要:
A method is presented to manufacture substrates for growing monocrystalline diamond films by chemical vapor deposition (CVD) on large area at low cost. The substrate materials are either Pt or its alloys, which have been subject to a single or multiple cycle of cleaning, roller press, and high temperature annealing processes to make the thickness of the substrate materials to 0.5 mm or less, or most preferably to 0.2 mm or less, so that either (111) crystal surfaces or inclined crystal surfaces with angular deviations within .+-.10 degrees from (111), or both, appear on the entire surfaces or at least part of the surfaces of the substrates. The annealing is carried out at a temperature above 800.degree. C. The present invention will make it possible to markedly improve various characteristics of diamond films, and hence put them into practical use.
摘要:
A diamond Schottky diode including an electrically conductive substrate, a multi-layer structure of a semiconducting diamond layer and an insulating diamond layer, and a metal electrode. This diode has a greater potential barrier under a reversed bias and hence exhibits better rectifying characteristics with a smaller reverse current.
摘要:
Thin diamond films can be selectively deposited imagewise on a substrate by gas phase synthesis. The substrate may be either a silicon substrate or a basal thin diamond film formed beforehand on a substrate by gas phase synthesis. Where a silicon substrate is used, its surface is first abraded to give a surface roughness suitable for gas phase synthesis of diamond. When a basal thin diamond film is used, a coating material capable of withstanding a temperature higher than a substrate temperature required for gas phase synthesis of diamond and having a high etching selectivity to diamond is needed to cover areas other than where the thin diamond film is to be newly formed. When a lift-off method is used, a thin masking film having a melting point higher than a temperature to be employed for gas phase synthesis of diamond can also be used in place of the coating material described above.
摘要:
A diamond thin film thermistor having a substrate, an electrically insulating diamond layer formed on the substrate by vapor-phase synthesis, a semiconducting diamond layer as a temperature-sensing part on the electrically insulating diamond layer by vapor-phase synthesis, and metal thin film electrodes attached to the semiconducting diamond layer. A plurality of such diamond thin film thermistors can simultaneously be formed on a single substrate, and the substrate is cut with a dicing saw to provide individual diamond thin film thermistor chips of the same quality.
摘要:
The present invention prevents cracking of a brake shoe even when the sliding surface of the brake shoe is heated to a high temperature and provides high reliability. The present invention provides a brake shoe for elevator emergency stop which generates a braking force by pressing brake shoes against a guide rail and making the brake shoes 5 slide to stop an elevator cage in the event of anomalies, including the brake shoes made of a cast iron material having a plurality of grooves 3 formed in a direction substantially perpendicular to the guide rail and gear teeth which constitute a sliding surface with the brake shoes 5 formed as gaps between the grooves, wherein the depth of the grooves is 3 mm or more and not more than 1.7 times the width of the gear teeth.