[en] GaN was deposited on patterned c-plane sapphire (0 0 0 1) wafers as the ELO technique without mask by metal organic chemical vapor deposition (MOCVD). The crystal structure and the growth mechanism were analyzed, this mechanism inhibited dislocations to extend to the surface of the epilayer and hollows between pits and epilayer released the stress of the material reducing the dislocation density. The properties of GaN layer were investigated by double crystal X-ray diffraction, atomic force microscopy, wet chemical etching and scanning electronic microscopy. The results proved that higher-quality GaN layer was received using this method