Open Access Highly Accessed Open Badges Nano Express

High Mg effective incorporation in Al-rich Al x Ga1 - x N by periodic repetition of ultimate V/III ratio conditions

Tongchang Zheng, Wei Lin*, Duanjun Cai, Weihuang Yang, Wei Jiang, Hangyang Chen, Jinchai Li, Shuping Li and Junyong Kang*

Author Affiliations

Department of Physics, Fujian Key Laboratory of Semiconductor Materials and Applications, Xiamen University, Xiamen 361005, People’s Republic of China

For all author emails, please log on.

Nanoscale Research Letters 2014, 9:40  doi:10.1186/1556-276X-9-40

Published: 21 January 2014


According to first-principles calculations, the solubility of Mg as a substitute for Ga or Al in AlxGa1 – xN bulk is limited by large, positive formation enthalpies. In contrast to the bulk case, the formation enthalpies become negative on AlxGa1 – xN surface. In addition, the N-rich growth atmosphere can also be favorable to Mg incorporation on the surface by changing the chemical potentials. On the basis of these special features, we proposed a modified surface engineering technique that applies periodical interruptions under an ultimate V/III ratio condition (extremely N-rich), to enhance Mg effective incorporation. By optimizing the interruption conditions (2 nm interruption interval with 2 s interruption time), the enhancement ratio can be up to about 5 in the Al0.99Ga0.01N epilayer.

First-principles calculations; MOVPE; AlGaN epilayer; High Mg incorporation; Ultimate V/III ratio