Nitride semiconductor device, and its fabrication process

Abstract

The invention provides a nitride semiconductor light-emitting device comprising gallium nitride semiconductor layers formed on a heterogeneous substrate, wherein light emissions having different light emission wavelengths or different colors are given out of the same active layer. Recessesare formed by etching in the first electrically conductive (n) type semiconductor layerformed on a substrate with a buffer layer interposed between them. Each recess is exposed in plane orientations different from that of the major C plane. For instance, the plane orientation of the A plane is exposed. An active layer is grown and joined on the plane of this plane orientation, on the bottom of the recess and the C-plane upper surface of a non-recess portion. The second electrically conductive (p) type semiconductor layer is formed on the inner surface of the recess. With the active layer formed contiguously to the semiconductor layer in two or more plane orientations, a growth rate difference gives rise to a difference in the thickness across the quantum well (active layer), giving out light emissions having different light emission wavelength peaks or different colors.