Specimens fromn‐type GaAs wafers have been annealed at high temperature (900–1050 °C) and then characterized using deep‐level transient spectroscopy (DLTS) and electron‐beam‐induced current techniques. Relatively short anneals result in substantial changes to the electron trap structure in this material. Diffusion lengths are, at best, marginally increased by short (16 min and below) anneals but have been found to be significantly increased by longer anneals of between 40 and 80 min. DLTS measurements of hole traps in both unannealed and annealedn‐type material suggest that a hole trap we term HCX may be an important recombination center in this class of material. The results obtained demonstrate the effectiveness of wafer annealing as a technique for creating a (10 mgr;m deep) near‐surface zone inn‐type bulk material in which defects are suppressed and diffusion lengths improved.
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