The spatial distribution of residual shallow acceptors in undoped semihyphen;insulating GaAs has been studied quantitatively by electronic Raman scattering with a spatial resolution of sim;50 mgr;m. This acceptor distribution has been correlated with the spatial distribution of the compensating EL2 donor in its neutral charge state measured by nearhyphen;IR absorption topography. An enhanced acceptor concentration is found in regions which show highhyphen;IR absorption: From the comparison with lowhyphen;temperature cathodoluminescence results, it is found that the intensity of the bandhyphen;tohyphen;acceptor recombination normalized to the bandhyphen;tohyphen;band luminescence intensity reproduces the acceptor distribution measured by Raman scattering. Implications of the present result on the compensation model for undoped semihyphen;insulating GaAs are discussed.
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