Photoconductivity in LPE GaP:Cu

The photoconductive properties of copper doped LPE GaP have been investigated. The photoresponse of as-grown surfaces extends from 2.2 to 5.0 eV. Photoconductive gains as high as 10⁵have been measured. The photoconductive response time to low levels of illumination is typically a few milliseconds and the spatial uniformity of the photosignal is less than 10% over distances of 3 mm. The photomechanism has been investigated by optical quenching and by study of the variation in photosignal with photon flux. These data are interpretable with the sensitized photoconductivity model.