By analyzing HB-LED model about electrical inject, optical output and calculating the distributing of electrical density photon output coupling efficiency at different top layer in HB-LED, we found the thicker of top layer and bottom layer, the easier for electrical spread and optical output. The calculating result showed that the thickness of top layer and bottom layer should be 49-98μm and 148μm, respectively The maximal external quantum efficiency of these types of LED is 12.05% and 20.12%.