MECHANISM FOR ENHANCEMENT OF ELECTRICAL ACTIVATION OF SILICON IN GAASBY ALUMINUM COIMPLANTATION

A pronounced enhancement in the electrical activation of implanted Si in GaAs is demonstrated by co-implantation of Al. The maximum enhancem ent (X 2) occurs when the Si distribution is shallow, there is a separ ation between the Si and Al distributions with the Al being deeper, th e Si and Al are implanted at doses of less-than-or-equal-to 1 X 10(13) cm-2, and subsequent annealing of the co-implanted GaAs is performed under capless or proximity cap conditions. A model considering getteri ng of the oxygen present in the bulk Czochralski-grown GaAs to the imp lanted Al is invoked to explain the observed activation enhancement.