Crystal orientation dependence of p-type contact resistance of GaN

The crystal orientation dependence in the p-type contact resistance of wurtzite GaN is theoretically investigated by considering the k-directional dependence of hole effective masses for the first time. The current-voltage characteristics of a metal-GaN junction has been calculated by using the so-called tunnelling model which includes both heavy- and light-hole transports. The obtained result suggests that the p-type contact resistance will be reduced when [1 0 (1) over bar 0] and [0 1 0 0] faces are properly used for contact interfaces. (C) 1998 Elsevier Science B.V. All rights reserved.