CORRELATION BETWEEN INTERFACIAL CHEMISTRY AND ELECTROSTATICS AT AN IRRADIATED N-CDTE AQUEOUS FLUORIDE JUNCTION

Three complementary techniques, namely laser Raman spectroscopy, electrolyte electroreflectance (EER), and capacitance-voltage measurements, were combined to establish a correlation between the interfacial chemistry and electrostatics at an irradiated n-CdTe/aqueous fluoride electrolyte interface. Thus, supra-bandgap irradiation of the latter was shown by laser Raman spectroscopy to produce a Te corrosion layer at the n-CdTe surface. This resulted in an additional voltage drop across this layer as indicated both by a modification of the EER profile and by the positive shift in the flatband potential, These new data provide chemical support for an (electrostatic) model proposed by earlier workers.