The optical activation of Zn ions which were implanted into an epitaxial film was performed by means of annealing under N over-pressures of up to 1.6GPa. By applying pressure, decomposition was avoided and the annealing temperature could be increased up to 1550C; instead of the limit of 1000 to 1100C at ambient pressures. The Zn-acceptor related photoluminescence intensity in implanted samples was maximized by annealing above 1350C. High-pressure annealing caused significant diffusion of implanted Zn atoms in the films. It was also possible to diffuse Zn from an external source into the implanted/unimplanted layers. High dislocation densities strongly accelerated Zn diffusion.

Optical activation and diffusivity of ion-implanted Zn acceptors in GaN under high-pressure, high-temperature annealing T.Suski, J.Jun, M.Leszczyński, H.Teisseyre, S.Strite, A.Rockett, A.Pelzmann, M.Kamp, K.J.Ebeling: Journal of Applied Physics, 1998, 84[2], 1155-7