Patent ID: 7704770
Filing Date: 2010-04-27
Classification: H01L

Abstract:
1. A method of producing light emitting diode by metal diffusion bonding technology, comprising the steps of: a) forming an AlInGaP LED epitaxial structure with a thickness less than 20 μm on a temporary substrate, and the LED epitaxial structure comprising a first confinement layer, an active light emitting layer and a second confinement layer sequentially deposited on the temporary substrate; b) forming a patterned transparent insulating current block layer on a portion of the top surface of the second confinement layer; c) forming an ohmic contact metal layer on the transparent insulating current block layer and the second confinement layer; d) providing a conducting permanent substrate with a thickness of 75 μm˜200 μm, and a coefficient of thermal expansion substantially within an approximating range of 4.9×10 e) using a metal diffusion bonding layer with a thickness less than 5 μm on both AlInGaP LED epitaxial structure and permanent substrate to perform the wafer diffusion bonding between AlInGaP LED epitaxial structure and permanent substrate under the following conditions: temperature of 400° C.˜700° C. and a pressure of 50 kg/cm f) removing the temporary substrate; and g) forming an ohmic contact metal layer on the first confinement layer of the semiconductor LED epitaxial structure, and performing an annealing process at a temperature of 400° C.˜600° C. such that the ohmic contact metal is diffused into the first confinement layer and formed discrete metal clusters therein, and performing wet chemical etches to remove part of the ohmic contact metal layer and some of the first confinement layer, and then using an ultrasonic cleaner to remove the etching residues to form a rough surface.