Abstract: A novel light-emitting device includes a sapphire substrate with a light-emitting layer comprising InXGa1−XN, where the critical value of the indium mole fraction X is determined by a newly derived relationship between the indium mole fraction X and the wavelength &lgr; of emitted light.

Abstract: Disclosed is a light-emitting semiconductor device which comprises an N-layer of N-type nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0, a P-layer of P-type nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0 and a Zn doped semi-insulating I-layer of nitrogen-Group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0. The semi-insulating I-layer has a 20 to 3000 .ANG. thickness and can emit light in the range of 485 to 490 nm. By employing the I-layer, the light-emitting diode as a whole can emit light in the range of 450 to 480 nm.

Abstract: A light-emitting diode or laser diode is provided which uses a Group III nitride compound semiconductor satisfying the formula (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N, inclusive of 0.ltoreq.x.ltoreq.1, and 0.ltoreq.y.ltoreq.1. A double hetero-junction structure is provided which sandwiches an active layer between layers having wider band gaps than the active layer. The diode has a multi-layer structure which has either a reflecting layer to reflect emission light or a reflection inhibiting layer. The emission light of the diode exits the diode in a direction perpendicular to the double hetero-junction structure. Light emitted in a direction opposite to the light outlet is reflected by the reflecting film toward the direction of the light outlet. Further, the reflection inhibiting film, disposed at or near the light outlet, helps the release of exiting light by minimizing or preventing reflection. As a result, light can be efficiently emitted by the light-generating diode.

Abstract: A nitrogen-group III compound semiconductor satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0, and a method for producing the same comprising the steps of forming a zinc oxide (ZnO) intermediate layer on a sapphire substrate, forming a nitrogen-group III semiconductor layer satisfying the formula Al.sub.x Ga.sub.y In.sub.1-x-y N, inclusive of x=0, y=0 and x=y=0 on the intermediate ZnO layer, and separating the intermediate ZnO layer by wet etching with an etching liquid only for the ZnO layer.

Abstract: An improved laser diode is made of a gallium nitride compound semiconductor ((Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N; 0.ltoreq.x.ltoreq.1; 0.ltoreq.x.ltoreq.1) with a double heterojunction structure having the active layer held between layers having a greater band gap. The laser diode comprises mirror surfaces formed by cleaving the multi-layered coating and the sapphire substrate in directions parallel to <0001> (c axis) of the sapphire substrate. The intermediate zinc oxide (ZnO) layer is selectively removed by wet etching with a ZnO-selective liquid etchant so as to form gaps between the sapphire substrate and the bottom-most sub-layer of the semiconductor laser element layer. The semiconductor laser element layer is cleaved with the aid of the gaps, and the resulting planes of cleavage are used as the mirror surfaces of the laser cavity.

Abstract: A gallium nitride group compound semiconductor laser diode (10) satisfying the formula (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N, inclusive of 0.ltoreq.x.ltoreq.1 and 0.ltoreq.y.ltoreq.1 comprises by a double hetero-junction structure sandwiching an active layer (5) between layers (4, 6) having wider band gaps than the active layer (5). The active layer (5) may comprise magnesium (Mg) doped p-type conductive gallium nitride group compound semiconductor satisfying the formula (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N, inclusive of 0.ltoreq.x.ltoreq.1 and 0.ltoreq.y.ltoreq.1 . In another embodiment, the active layer (5) is doped with silicon (Si).

Abstract: Disclosed are a gallium nitride type semiconductor device that has a single crystal of (Ga.sub.1-x Al.sub.x).sub.1-y In.sub.y N, which suppresses the occurrence of crystal defects and thus has very high crystallization and considerably excellent flatness, and a method of fabricating the same. The gallium nitride type semiconductor device comprises a silicon substrate, an intermediate layer consisting of a compound containing at least aluminum and nitrogen and formed on the silicon substrate, and a crystal layer of (Ga.sub.1-x Al.sub.x).sub.1-y In.sub.y N (0.ltoreq.x.gtoreq.1, 0.ltoreq.y.ltoreq.1, excluding the case of x=1 and y=0). According to the method of fabricating a gallium nitride base semiconductor device, a silicon single crystal substrate is kept at a temperature of 400.degree. to 1300.degree. C.

Abstract: A compound semiconductor vapor phase epitaxial device comprises a cylindrical reactor vessel, a plurality of flow channels disposed in the reactor vessel, a crystal substrate disposed in one of the flow channels, a plurality of gas supply pipes for respectively supplying gas containing element of compound to be grown on the crystal substrate and at least one slit or linearly arranged fine holes communicating adjacent two flow channels so as to extend in a direction normal to a direction of the gas flow to form a laminate layer flow consisting of two or more than two gases at an upstream portion of location of the crystal substrate.

Abstract: A gallium nitride group compound semiconductor laser diode includes at least one pn junction layer disposed between an n-type layer and a p-type layer. The n-type layer is formed from a gallium nitride group compound semiconductor material defined by the composition equation (Al.sub.x Ga.sub.1-x).sub.y In.sub.1-y N (where 0.ltoreq.x.ltoreq.1 and 0.ltoreq.y.ltoreq.1). The p-type layer, doped with an acceptor impurity, is obtained by electron beam irradiating a gallium nitride group compound semiconductor material defined by the composition equation (Al.sub.x' Ga.sub.1-x').sub.y' In.sub.1-y' N (where 0.ltoreq.x'.ltoreq.1, 0.ltoreq.y'.ltoreq.1, x=x' or x.noteq.x', and, y=y' or y.noteq.y'). The improved gallium nitride group semiconductor laser diode of the present invention is found to emit light in the visible short wavelength spectrum of light which includes the blue, violet and ultraviolet regions.

Abstract: Disclosed are a gallium nitride type semiconductor device that has a single crystal of (Ga.sub.l-x Al.sub.x).sub.l-y In.sub.y N, which suppresses the occurrence of crystal defects and thus has very high crystallization and considerably excellent flatness, and a method of fabricating the same. The gallium nitride type semiconductor device comprises a silicon substrate, an intermediate layer consisting of a compound containing at least aluminum and nitrogen and formed on the silicon substrate, and a crystal layer of (Ga.sub.l-x Al.sub.x).sub.l-y In.sub.y N (0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, excluding the case of x=1 and y=0). According to the method of fabricating a gallium nitride base semiconductor device, a silicon single crystal substrate is kept at a temperature of 400 to 1300.degree. C.