The use of a 100‐kW water‐walled dc argon lamp to anneal ion‐implanted GaAs is reported. Annealing cycles of 3 and 10 s and peak temperatures from 950 to 1200 °C have been used to anneal Be, Si, and Zn implanted following representative implant schedules of technological importance. It is demonstrated that this technique is superior to conventional furnace anneal techniques in terms of the doping profiles, peak carrier concentrations, activation efficiencies (particularly at high doses), and mobilities achieved. The annealing technique should be applicable to large volume GaAs integrated circuit production and 100‐mm‐diam wafers can be annealed in a single exposure with better than 2% temperature uniformity (Si data).