Inversion of wurtzite GaN (0001) by exposure to magnesium
Magnesium incorporation during the molecular-beam epitaxy growth of wurtzite GaN is found to invert the Ga-polar (0001) face to the N-polar face. The polarity is identified based on the two different sets of reconstructions seen on the film prior to and after about 1 monolayer Mg exposure. The inversion boundary is seen to lie on the (0001) plane from transmission electron microscopy images, and a structural model is presented for the inversion. On the Ga-polar face, Mg is also seen to stabilize growth in the N-rich regime.
Northrup, J. E. ; Feenstra, R. M.; Sarney, W. ; Salamanca, L. ; Romano, L. T. ; Greve, D. W. Inversion of wurtzite GaN (0001) by exposure to magnesium. Applied Physics Letters. 1999 August 9; 75 (6): 808-810.