Spectral distribution of photoelectric quantum yield of thin-film Au-CdTe diode structure

Abstract

A study of the Au/CdTe Schottky diodes fabricated by vacuum evaporation of a semitransparent Au layer over an electrodeposited CdTe thin film is reported. The theoretical model of the photocurrent spectra for an Au/CdTe Schottky diode based on the continuity equation and incorporating the surface recombination losses does not explain the measured spectra in the entire range of wavelengths, particularly the above-mentioned decay in the short-wavelength region. The satisfactory description of the measured spectra is achieved by proposing a model, in which the surface recombination along with the Schottky effect resulted in the presence of a dead layer in the space-charge region is taken into account. By varying the parameters such as uncompensated carrier concentration and carrier lifetime, the above model can explain the actual photoresponse spectra.