Abstract: The present invention provides an epitaxial wafer having compound semiconductor epitaxial layer provided on a substrate, a total thickness of a portion of the compound semiconductor epitaxial layers comprises Ga, As and P as constituent elements being not less than 80 &mgr;m and in the epitaxial layer a low carrier concentration region with a carrier concentration of from 0.5 to 9×1015 cm−3 doped with nitrogen being formed.

Abstract: In a light-emitting diode, which comprises epitaxial wafer where a gallium phosphide or a gallium phosphide arsenide mixed crystal epitaxial layer is grown on a III-V family compound single crystal substrate having zinc blende type crystal structure, the surface of said substrate has a plane tilted by 5 to 16.degree. from a (100) plane toward ?010!, ?001!, ?0-10! or ?00-1!, or a plane having crystallographically equivalent crystal plane orientation to this plane. As a result, it is possible to improve light emitting output and to ensure longer service life.

Abstract: The present invention relates to an epitaxial wafer including a PN junction, which is improved in terms of light output and can have a good-enough ohmic electrode formed thereon. Epitaxial layers are formed of GaAs.sub.1-x P.sub.x where 0.45 <.times..ltoreq.1). A first P-type layer is formed by a vapor-phase growth process, and a second P-type layer is formed on the first P-type layer by a thermal diffusion process, said second P-type layer having a carrier concentration higher than that of said first P-type layer.

Abstract: In an epitaxial wafer of gallium arsenide phosphide, a single crystal substrate is provided thereon with a gallium arsenide phosphide layer with a varying mixed crystal ratio, a gallium arsenide phosphide layer with a constant mixed crystal ratio, and a nitrogen-doped gallium arsenide phosphide layer with a constant mixed crystal ratio. The nitrogen-doped gallium arsenide phosphide layer with a constant mixed crystal ratio has a carrier concentration of 3.times.10.sup.15 cm.sup.-3 or less.

Abstract: There is provided a method for suppressing generation of cracks or damages on a compound semiconductor epitaxial wafer during an epitaxial growth due to growth of an epitaxial layer on the rear surface at the edge of the epitaxial layer which is located at the upstream side of the flow of the source gas. In manufacturing a semiconductor wafer by growing a single crystal semiconductor epitaxial layer having a zinc blend structure on a single crystal semiconductor substrate having a zinc blend structure, the surface of the single crystal semiconductor substrate has (100) surface orientation having an off angle and a source gas is supplied in the direction of the off angle or in a direction at 30.degree. or less to the direction at 180.degree. thereto.

Abstract: A mixed crystal ratio difference is introduced in a gallium arsenide phosphide mixed crystal layer having a desired constant mixed crystal ratio, thereby reducing the amount of stress remaining within the resulting epitaxial wafer. This is less likely or unlikely to crack, and so can be well used for LED fabrication.

Abstract: A double hetero type epitaxial wafer contains a single crystal substrate, first and second conductivity type clad layers which are opposite and are made of mixed crystal compounds of Group III-V which had an indirect transition type band structure, and an active layer made of a mixed crystal compound of Group III-V which has a direct transition type band structure and is interposed between the respective clad layers, wherein the first conductivity type clad layer has a refractive index smaller than that of the second conductivity type clad layer.

Abstract: In an epitaxial wafer comprising of a single crystalline substrate, a p type gallium aluminum arsenide mixed crystalline layer and n type gallium aluminum arsenide mixed crystalline layer having an indirect transition type band structure. The p type gallium aluminum arsenide mixed crystalline layer consists of a gallium aluminum arsenide mixed crystalline layer having a direct transition type band structure, positioned about 3 to 10 .mu.m from the pn junction and a gallium aluminum arsenide mixed crystalline layer having an indirect transition type band structure. The aluminum arsenide mixed crystal ratio in the gallium aluminum arsenide is exponentially and gradually changed in the region between the direct transition type layer and the indirect transition type layer.