中国物理B ›› 2014, Vol. 23 ›› Issue (6): 67803-067803.doi: 10.1088/1674-1056/23/6/067803

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

N vacancy, substitutional O, and Al defects in the bandgap of composition-tunable nonstoichiometric AlN powder

张电, 刘发民, 蔡鲁刚   

  1. Department of Physics, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China
  • 收稿日期:2013-12-12 修回日期:2014-01-19 出版日期:2014-06-15 发布日期:2014-06-15

N vacancy, substitutional O, and Al defects in the bandgap of composition-tunable nonstoichiometric AlN powder

Zhang Dian (张电), Liu Fa-Min (刘发民), Cai Lu-Gang (蔡鲁刚)   

  1. Department of Physics, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China
  • Received:2013-12-12 Revised:2014-01-19 Online:2014-06-15 Published:2014-06-15
  • Contact: Liu Fa-Min E-mail:fmliu@buaa.edu.cn

PDF (PC)

555

赞

摘要： AlN powders are prepared by direct nitridation via Al liquid and vapor phases in mixed atmospheres of N2 and NH3 with different NH3/N2 ratios. The reaction analysis reveals that NH3 acts as catalyst for N2 dissociation and the transportations of N, O, and Al in the liquid phase are different from those in the vapor phase. Accordingly, the products are Al-rich and composition-tunable nonstoichiometric AlN in which N, O, and Al content values change with nitridation atmosphere and temperature, leading to the variation of the relevant defect concentration. Therefore, the AlN powders exhibit prominent absorption bands around 5.30, 3.40, and 1.50 eV, which are tentatively assigned to VN, ON donors, and AlN acceptor respectively. Furthermore, a new donor named [VN-ON] complex is predicted at 4.40 eV within the 5.90 eV bandgap. It is demonstrated that the optical spectra of nonstoichiometric AlN are preferable to the nominal stoichimometric one for the identification of the defects energy level.

关键词: Ⅲ-V semiconductors, defects, optical properties, luminescence

Abstract: AlN powders are prepared by direct nitridation via Al liquid and vapor phases in mixed atmospheres of N2 and NH3 with different NH3/N2 ratios. The reaction analysis reveals that NH3 acts as catalyst for N2 dissociation and the transportations of N, O, and Al in the liquid phase are different from those in the vapor phase. Accordingly, the products are Al-rich and composition-tunable nonstoichiometric AlN in which N, O, and Al content values change with nitridation atmosphere and temperature, leading to the variation of the relevant defect concentration. Therefore, the AlN powders exhibit prominent absorption bands around 5.30, 3.40, and 1.50 eV, which are tentatively assigned to VN, ON donors, and AlN acceptor respectively. Furthermore, a new donor named [VN-ON] complex is predicted at 4.40 eV within the 5.90 eV bandgap. It is demonstrated that the optical spectra of nonstoichiometric AlN are preferable to the nominal stoichimometric one for the identification of the defects energy level.

Key words: Ⅲ-V semiconductors, defects, optical properties, luminescence

中图分类号:  (III-V and II-VI semiconductors)

  • 78.30.Fs
68.55.Ln (Defects and impurities: doping, implantation, distribution, concentration, etc.) 78.40.-q (Absorption and reflection spectra: visible and ultraviolet) 78.55.-m (Photoluminescence, properties and materials)