DETERMINATION OF WURTZITE GAN LATTICE POLARITY BASED ON SURFACE RECONSTRUCTION

We identify Mo categories of reconstructions occurring on wurtzite GaN surfaces, the first associated with the N face, (<000(1)over bar>), a nd the second associated with the Ga face, (0001). Not only do these t wo categories of reconstructions have completely different symmetries, but they also have different temperature dependence. It is thus demon strated that surface reconstructions can be used to identify lattice p olarity. Confirmation of the polarity assignment is provided by polari ty-selective wet chemical etching of these surfaces. (C) 1998 American Institute of Physics.