Patent ID: 7016392
Filing Date: 2006-03-21
Classification: H01S

Abstract:
1. A light-emitting device, comprising: a substrate comprising gallium arsenide; an active region comprising an n-type spacing layer and a p-type spacing layer; and a tunnel junction structure comprising a p-type tunnel junction layer adjacent the p-type spacing layer, an n-type tunnel junction layer and a tunnel junction between the p-type tunnel junction layer and the n-type tunnel junction layer, in which: the p-type tunnel junction layer comprises a layer of a p-type first semiconductor material including gallium and arsenic; and the n-type tunnel junction layer comprises a layer of an n-type second semiconductor material including indium, gallium and phosphorus; wherein the second semiconductor material has an indium fraction that provides the second semiconductor material with a lattice constant that matches that of the first semiconductor material, where the first semiconductor material is gallium arsenide, and the second semiconductor material is indium gallium phosphide of which the indium gallium phosphide has an indium fraction of 0.4 to 0.6.