LED Epitaxial Wafer and Fabrication Process Thereof

An LED epitaxial wafer, comprising a substrate, a buffer layer, a U-type GaN layer, an N-type GaN layer, a quantum well light-emitting layer, a P-type electron blocking layer and a P-type GaN layer which are successively arranged in a stack, characterized in that the N-type GaN layer comprises:

• an N_SL layer and an N_Bulk layer provided on the N_SL layer;
• and the thickness of the N_SL layer is less than the thickness of the N_Bulk layer;
• the N_SL layer comprises several first N_SL layers and several second N_SL layers;
• the N_Bulk layer comprises a first N_Bulk layer and a second N_Bulk layer arranged on the first N_Bulk layer;
• the silicon doping concentration of the first N_SL layer is less than the silicon doping concentration of the second N_SL layer;
• the silicon doping concentration of the first N_Bulk layer is greater than the silicon doping concentration of the second N_Bulk layer;
• and the silicon doping concentration of the first N_SL layer is less than the silicon doping concentration of the second N_Bulk layer;
• the first N_SL layer and the second N_SL layer are successively and cyclically arranged from bottom to top, with the number of cycles being 10-20;
• the growth temperature of the first N_SL layer is 1000-1200° C., the growth temperature of the second N_SL layer is 1000-1200° C., the growth temperature of the first N_Bulk layer is 1000-1200° C., and the growth temperature of the second N_Bulk layer is 900-1100° C.