Simple interpretation of metal/wurtzite-GaN barrier heights

Photoemission data for the dependence of the Schottky barrier height on the metal work function, for n-type wurtzite GaN, are discussed in terms of th e Cowley-Sze model [J. Appl. Phys. 36, 3212 (1965)] for a uniform density o f surface states in the band gap. It is suggested that, in the context of t his model, such barrier heights can be expressed largely as a sum of the "b are-surface barrier height" (i.e., the band bending before contact formatio n) and a Mott-Schottky term. (C) 1999 American Institute of Physics. [S0021 -8979(99)02414-7].