The ion-implantation p-type doping of Al0.75Ga0.25Sb was studied. The surface morphology and electrical properties were shown, by using atomic force microscopy and Hall measurements, to be degraded after rapid thermal annealing at 650C. The implantation of Be and Mg resulted in sheet hole concentrations which were twice those of the implanted acceptor dose (1013/cm2) after 600C annealing. This was attributed to double acceptor or antisite defect formation. The implanted C acted as an acceptor, but also demonstrated an excess hole conduction which was attributed to implantation-induced defects. Implanted Zn required a higher annealing temperature than did Be or Mg, in order to achieve 100% effective activation for a dose of 1013/cm2. It was suggested that this was probably the result of the greater implantation-induced damage that was created by the heavier Zn ion. The secondary ion mass spectroscopy of as-implanted and annealed Be, Mg and C samples was studied. The diffusion of implanted Be (5 x 1013cm2, 45keV) was shown to exhibit an inverse dependence upon temperature. This was attributed to a substitutional-interstitial diffusion mechanism. Implanted Mg (1014/cm2, 110keV) exhibited marked redistribution, and losses of up to 56% at the interface, after 600C annealing. Implanted C (2.5 x 1014/cm2, 70keV) exhibited no redistribution, even after annealing at 650C.

J.C.Zolper, J.F.Klem, A.J.Howard, M.J.Hafich: Journal of Applied Physics, 1996, 79[3], 1365-70