The results of Hall effect and resitivity measurements on p-GaAs implanted with 67Ga(→ 67Zn) and semiinsulating GaAs implanted with 71As(→ 71Ge → 71Ga) are presented. In either case, time dependent changes of the carrier concentration and resitivity according to the half-life of involved probe atoms could be observed.
In the case of 67Ga, transmutation from the electrically neutral Ga to the single acceptor ZnGa occurs.
For 71As a transformation into the single acceptor GeAs is observed. However, the finally resulting GaAs does not act as a double acceptor, but seems to have a compensating effect.