The III-V semiconductor GaN is of technological interest because of its high band gap (3.44 eV at 300 K). The impurities K, Ca, Zn, B, Al, C, Si, P, As, S, F, and Cl have been implanted into GaN. After annealing the optical spectra of the implanted material were investigated. Studies were also made of neutron irradiated GaN and some Ga1-xAlxN alloys. Broad emission bands at 2.9, 2.85, and 2.58 eV were identified with the impurities Zn, P, and As respectively. Sharper emissions near 3.5 and 3.3 eV were seen in the Al implant. Peaks near 3.27 eV, associated with DA pair transitions in purer GaN, were seen in the B, Al, F and Cl implants. The intrinsic luminescence of most samples is reduced by an amount dependent on the damage introduced during implantation. A broad band near 2.2 eV is associated with defects introduced by implantation and by the dissociation of GaN during high temperature annealing. A reduction in efficiency of implanted luminescence centres is also associated with high temperature annealing.
|Date of Award||1976|