Patent ID: 7871843
Filing Date: 2011-01-18
Classification: B82Y,H01L,H01S

Abstract:
1. A method of preparing a light emitting device structure having an n-type nitride semiconductor layer, an active layer and a p-type nitride semiconductor layer in order on a substrate and comprising an Al x Ga 1-x N (0≦x≦1) layer included in said n-type nitride semiconductor layer or said p-type nitride semiconductor layer, said Al x Ga 1-x N (0≦x≦1) layer being obtained by a supercritical ammono process compressing the steps of: (i) providing a feedstock containing at least one of gallium and aluminum, a mineralizer containing alkali metal or alkali metal complex, a wafer including at least a part of said n-type nitride semiconductor layer or said p-type nitride semiconductor layer formed on the surface thereof and ammonia-containing solvent containing ammonia or derivative thereof in a reactor; (ii) bringing said ammonia containing solvent in super-critical state; (iii) maintaining a dissolution zone in said reactor, where said feedstock is disposed, at a dissolution temperature thereby dissolving at least a part of said feedstock into said ammonia-containing solvent in supercritical state: and (iv) maintaining a crystallization zone in said reactor, where said wafer is disposed, at a crystallization temperature higher than said dissolution temperature thereby crystallizing said Al