Plasma damage in p-GaN

The effect of Inductively Coupled Plasma H-2 or Ar discharges on the breakdown voltage of p-GaN diodes was measured over a range of ion energies and fluxes. The main effect of plasma exposure is a decrease in net acceptor concentration to depths of 400-550 Angstrom. At high ion fluxes or energies there can be type conversion of the initially p-GaN surface. Post etch annealing at 900 degrees C restores the initial conductivity.