CALCULATIONS OF NATIVE DEFECTS IN CUBIC ALN

We have studied the electronic structure of native defects in cubic AI N. N and Al vacancies, antisites and interstitials are investigated in different charge states. We have performed first-principles calculati ons based on density-functional theory, using two methods. The first o ne is the Green-function technique based on the linear muffin-tin orbi tal method in the atomic-spheres approximation. Defects considered are all ideal substantial ones, i.e., no relaxation of the neighboring at oms is allowed for in this method. The results for aluminium vacancy a nd for nitrogen antisite are compared to the calculations using superc ell approach and the fall-potential linear muffin-tin orbital (tile se cond method) with lattice relaxation included.