Abstract: Through a chemical vapor deposition process, a tubular graphite body is fabricated as a hydrogen storage element that comprises a tubular graphite body forming an elongated shell and at least one metal plug closing an open end of the elongated shell so as to form a closed inside space for storing hydrogen gas.

Abstract: A process of producing graphite fiber which includes the generation of the fiber by chemical vapor deposition using an organo metal compound which includes a metal catalyst and the use of a less reactive substance as a substrate to adhere carbon or metal at specific positions on the substrate. And a process of producing graphite fibers by chemical vapor deposition of fine particles of nickel, iron or cobalt as catalyst and use of an organic compound as a source of carbon which includes generating the fibers at a temperature between 650.degree. C. and 800.degree. C.

Abstract: A testing sample is formed in a three-story structure consisting of a photo-resist 13, a silicon dioxide film 12, and a GaAs substrate 11. The pattern of the photo-resist 13 is transferred onto the silicon dioxide film 12 by effecting the photo-resist 13 as a mask. Thus obtained silicon dioxide film mask 14 and the GaAs substrate 11 are processed in compliance with a reactive ion beam etching method; that is, the silicon dioxide film mask 14 and the GaAs substrate 11 are irradiated by the chlorine ion beam 15. The silicon dioxide film and the GaAs substrate are gradually etched by the irradiation of the chlorine ion beam 15. In this case, the etching is differently developed in two regions. In one region which is not covered by the mask, the etching advances uniformly in a normal direction with respect to the GaAs substrate at a certain etching rate.

Abstract: The substrate of a gallium nitride light-emitting diode is made rough at given positions on the surface thereof, or an insulating film strip pattern is attached on the surface of the substrate prior to growing an n-type conductive gallium nitride layer and a semi-insulating gallium nitride layer thereon. As a result, high conductivity regions are formed in the semi-insulating layer at positions corresponding to the rough surfaces or the insulating film strip pattern in such a manner that each of the high conductivity region extends from the n-type conductive layer to the upper surface of the semi-insulating layer so as to function as a conductor to be connected to an electrode. In the same manner similar high conductive regions are made along kerf portions in a diode wafer, preventing each diode chip from being damaged on cutting.

Abstract: An electroluminescent semiconductor device comprising bodies of conductive and resistive crystalline gallium nitride (GaN) which are successively epitaxially deposited on a surface of a heat-treated sapphire substrate, and a body of insulative crystalline gallium nitride epitaxially deposited on the resistive body.

Abstract: An electroluminescent semiconductor device comprising bodies of conductive and resistive crystalline gallium nitride (GaN) which are successively epitaxially deposited on a surface of a heat-treated sapphire substrate, and a body of insulative crystalline gallium nitride epitaxially deposited on the resistive body.

Abstract: The substrate of a gallium nitride light-emitting diode is made rough at given positions on the surface thereof, or an insulating film strip pattern is attached on the surface of the substrate prior to growing an n-type conductive gallium nitride layer and a semi-insulating gallium nitride layer thereon. As a result, high conductivity regions are formed in the semi-insulating layer at positions corresponding to the rough surfaces or the insulating film strip pattern in such a manner that each of the high conductivity region extends from the n-type conductive layer to the upper surface of the semi-insulating layer so as to function as a conductor to be connected to an electrode. In the same manner similar high conductive regions are made along kerf portions in a diode wafer, preventing each diode chip from being damaged on cutting.

Abstract: A nitrogen-doped n-type epitaxial layer of GaP grown from a vapor phase is heated at a temperature ranging from 740.degree. to 1000.degree.C for a selected period of time depending on the temperature. The heat treatment is carried out in H.sub.2, N.sub.2 or Ar in the presence of Ga and P vapors. Alternatively, a protection coating of SiO.sub.2, Si.sub.3 N.sub.4 or Al.sub.2 O.sub.3 is formed on the epitaxial layer prior to the heat treatment.