Concentration of point defects in wurtzite AlN: A hybrid functional study
School of Electrical Engineering and Telecommunications, University of New South Wales Sydney, NSW 2052, Australia
2 Silanna Semiconductor - Sydney Olympic Park, Sydney, NSW 2127, Australia
3 School of Physics, The University of Melbourne - Melbourne, VIC 3010, Australia
Accepted: 17 April 2012
Formation energies and concentrations of the most relevant point defects in n-type wurtzite AlN are obtained by first-principle calculations employing a hybrid functional. We show that the incorporation of Si is favoured over O under N-rich growth conditions, but not under Al-rich conditions. The triply negatively charged Al vacancy is found to be the defect with the lowest formation energy in n-type AlN and it is therefore expected to be the main compensating acceptor. Under typical physical vapor-phase transport growth conditions, we predict Si concentrations of up to 1020 cm− 3 and net donor concentrations of about 1018 cm− 3, in good agreement with available experimental data.
PACS: 61.72.uj – III-V and II-VI semiconductors / 61.72.J- – Point defects and defect clusters / 71.55.Eq – III-V semiconductors
© EPLA, 2012