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arXiv · cond-mat/9807190

Theoretical evidence for the semi-insulating character of AlN

Antonella Fara·Fabio Bernardini·Vincenzo Fiorentini
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Abstract

We present ab initio density-functional calculations for acceptors, donors, and native defects in aluminum nitride, showing that acceptors are deeper (Be ~ 0.25 eV, Mg_ 0.45 eV) and less soluble than in GaN; at further variance with GaN, both the extrinsic donors Si_Al and C_Al, and the native donor V_N (the anion vacancy) are found to be deep (about 1 to 3 eV below the conduction). We thus predict that doped AlN will generally turn out to be semi-insulating in the normally achieved Al-rich conditions, in agreement with the known doping difficulties of high-x AlGaN alloys.

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Antonella Fara, Fabio Bernardini, Vincenzo Fiorentini. 1998-07-13. Theoretical evidence for the semi-insulating character of AlN. https://doi.org/10.1063/1.369197

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