ULTRAVIOLET LIGHT-EMITTING DIODE EPITAXIAL STRUCTURE AND PREPARATION METHOD THEREFOR

摘要

Provided are an ultraviolet light-emitting diode epitaxial structure and a preparation method therefor. The method comprises: providing a substrate (100); growing a high temperature AlN layer (101) first; then growing a low temperature AlN layer (102); further growing a high temperature AlN layer (101); growing an n-type AlGaN layer (103); growing an active layer (104); and growing a p-type AlGaN layer (106). Since the low temperature AlN layer (102) is in three-dimensional small islands rather than a two-dimensional thin film, as the high temperature AlN layers (101) are further grown continuously, the three-dimensional small islands grow gradually and merge with each other; in the process of merging the islands, dislocations extending from the lower AlN layer can be bent, thus increasing the probability of dislocations annihilating each other, improving the crystal quality of the upper AlN layer, improving the whole crystal quality of the epitaxial structure layer material, and improving the luminance of an ultraviolet LED.