Implant isolation of GaAs.

The ion species and dose dependence of implant-induced isolation of GaAs was investigated by Hall-effect, Rutherford backscattering and secondary ion mass spectrometry. The principal deep states responsible for the compensation have levels around E(c) -0. 4 eV and E(c) -0.7 eV. The initial conductivity of the GaAs is restored by annealing at 600C, regardless of implant dose or species (O, F or Ne), and the maximum resistivity in the material occurs for 500C annealing. Below this temperature hopping conduction leads to intermediate resistivity values. A critical review is given of isolation schemes reported previously.