In this paper, formation of low resistance ohmic contact to p-type GaN using an alloy of Ni/Cu was reported. The Mg doped samples were deposited with Ni (20 nm)/Cu (20 mn) and then annealed in nitrogen ambient at different annealing temperatures ranging from 400 to 700 degreesC. A good ohmic contact with a specific contact resistance of 1.31 X 10(-4) Omega cm(2) was obtained when the sample was annealed at 600 degreesC for 30 s. The decrease of specific contact resistance is attributed to the increased contact area and local electric field, and extraction of hydrogen from the p-type GaN. (C) 2003 Elsevier Science B.V. All rights reserved.