Fabrication and characteristics of A Te-Se-CdO structure
AbstractA Te-Se-CdO layer structure has been fabricated by epitaxial growth of a selenium film on a monocrystalline tellurium substrate, followed by deposition of the counterelectrode by reactive sputtering from a cadmium target in the presence of a trace of air. Examination by RHEED has shown the counterelectrode to be CdO in polycrystalline form and the selenium film to be monocrystalline. The structures were found to give a maximum photovoltaic responsivity near 550 nm, at which wavelength the quantum efficiency was around 60% for a CdO thickness of 0.2 micron. The responsivity was affected by the CdO film thickness and the contacts to it but was insensitive to conditions relating to the selenium film, with variations in the thickness up to 10 microns, in the orientation between the (0001) and
$$(10\overline 1 0)$$
 planes and in the polishing conditions of the tellurium stustrate. Values of equivalent series and shunt resistance were determined from output current-voltage results by curve fitting and the shunt resistance was found to vary inversely with illuminance.