Electronic Structures of Wurtzite GaN with Ga and N Vacancies  

作　　者：庞超 史俊杰 张艳 K.S.A.Butcher T.L.Tansley J.E.Downes 尚家香 

机构地区：[1]State Key Laboratory [or Mesoscopic Physics, and School of Physics, Peking University, Beijing 100871 [2]Semiconductor Science and Technology Laboratories, Department of Physics, Macquarie University, New South Wales 2109, Australia [3]School of Materials Science and Engineering, Beijlng University of Aeronautics and Astronautics, Beijing 100083

出　　处：《Chinese Physics Letters》2007年第7期2048-2051,共4页中国物理快报（英文版）

摘　　要：The electronic band structures of wurtzite GaN with Ga and N vacancy defects are investigated by means of the first-principles total energy calculations in the neutral charge state. Our results show that the band structures can be significantly modified by the Ga and N vacancies in the GaN samples. Generally, the width of the valence band is reduced and the band gap is enlarged. The defect-induced bands can be introduced in the band gap of GMV due to the Ga and N vacancies. Moreover, the GaN with high density of N vacancies becomes an indirect gap semiconductor. Three defect bands due to Ga vacancy defects are created within the band gap and near the top of the valence band. In contrast, the N vacancies introduce four defect bands within the band gap. One is in the vicinity of the top of the valence band, and the others are near the bottom of the conduction band. The physical origin of the defect bands and modification of the band structures due to the Ga and N vacancies are analysed in depth.The electronic band structures of wurtzite GaN with Ga and N vacancy defects are investigated by means of the first-principles total energy calculations in the neutral charge state. Our results show that the band structures can be significantly modified by the Ga and N vacancies in the GaN samples. Generally, the width of the valence band is reduced and the band gap is enlarged. The defect-induced bands can be introduced in the band gap of GMV due to the Ga and N vacancies. Moreover, the GaN with high density of N vacancies becomes an indirect gap semiconductor. Three defect bands due to Ga vacancy defects are created within the band gap and near the top of the valence band. In contrast, the N vacancies introduce four defect bands within the band gap. One is in the vicinity of the top of the valence band, and the others are near the bottom of the conduction band. The physical origin of the defect bands and modification of the band structures due to the Ga and N vacancies are analysed in depth.

关 键 词：GENERALIZED GRADIENT APPROXIMATION LIGHT-EMITTING-DIODES NATIVE DEFECTS GALLIUM NITRIDE AIN INN 

分 类 号：O44[理学—电磁学]