Abstract: 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.

Abstract: 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.

Abstract: Disclosed herein is a MIS type diamond field-effect transistor comprising a diamond semiconductor layer provided as an active layer by chemical vapor deposition (CVD), and a diamond insulator layer provided on the diamond semiconductor layer also by CVD, a gate electrode being formed on the diamond insulator layer, wherein a diamond insulator undercoat is provided on a non-diamond substrate by CVD, and the diamond semiconductor layer and the diamond insulator layer are sequentially provided on the diamond insulator undercoat. The MIS type diamond field-effect transistor with this structure ensures that in the manufacture thereof, a diamond insulator undercoat of large area can be formed on a non-diamond substrate of CVD, whereby a large number of elemental devices can be fabricated simultaneously.

Abstract: 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.

Abstract: 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.

Abstract: 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.