Electrical profiling and optical activation studies of Be-implanted GaAs

Differential resistivity and Hall-effect measurements have been utilized to study the annealing behavior and electrical carrier-distribution profiles of Be-implanted GaAs. A maximum of 90--100% electrical activation occurs during 9000C anneals for implanted Be concentrations less than approx.5 x 1018 cm-3. For higher fluences, however, a heavily concentration-dependent diffusion is observed, and the measured electrical activation is complicated by outdiffusion of Be into the Si3N4 encapsulant. In these cases, a maximum in the electrical activation appears for annealing near 7000C. Low-temperature (50K) photoluminescence substantiates previous findings that 9000C annealing results in maximum optical activation and lattice recovery