Rapid annealing of GaAs: Uniformity and temperature dependence of activation.

Scanning microwave photoconductance, capacitance-voltage profiling and Hall effect measurements were used to investigate the uniformity of activation of Si, Be and Mg implanted 2" and 3" diameter, semi-insulating GaAs substrates after rapid thermal annealing in a commercial furnace. The results indicate that carrier lifetimes and mobilities for low dose (3-4 x 10(12) cm(-2)) implants and carrier densities for high dose (1 x 10 (15) cm(-2)) implants are comparable or superior in rapidly annealed substrates to those obtained in thermally annealed implanted layers. The uniformity of these parameters is not significantly different for wafers annealed by either method. The temperature dependence of damage removal and carrier activation in the implanted regions during both furnace and transient annealing was also investigated, and demonstrates that the microwave photoconductance technique gives results for donor implantation correlating well with conventional backscattering and electrical measurements respectively.