Patent ID: 8450767
Filing Date: 2013-05-28
Classification: H01L

Abstract:
1. A light-emitting device comprising: a substrate; a transparent conductive layer disposed on the substrate; a semiconductor window layer formed on the transparent conductive layer and having a flat surface and a plurality of recesses, wherein each of the recesses having a side wall surface; a light-emitting stack formed on the semiconductor window layer and comprising a first conductivity semiconductor layer, a second conductivity semiconductor layer, and an active layer sandwiched between the first and second conductivity semiconductor layers; and an ohmic contact layer formed on the flat surface of the semiconductor window layer for ohmically contacting with the transparent conductive layer, wherein the side wall surface of one of the recesses is inclined with respect to the flat surface, and the contact resistance between the flat surface and the transparent conductive layer is less than that between the side wall surface and the transparent conductive layer, and wherein a surface area ratio of the surface area of the ohmic contact layer to the surface area of the semiconductor window layer ranges from 10% to 90%.