GENERAL PROPERTIES OF SNO2-GAAS AND SNO2-GE HETEROJUNCTION PHOTO-VOLTAIC CELLS

SnO2 - Ge and Sn02-GaAs heterojunction formed by chemical vapor deposition have been investigated. The results show that (n-n) Sn02-GaAs, (n-p) Sn02-GaAs, and (n-n) Sn02-Ge heterojunctions give a photovoltaic effect, while (n-p) Sn02-Ge yields an ohmic contact. The measured short-circuit currents, arising mainly from semiconductor side, are comparable with those for “AMOS” and homojunction solar cells. The open-circuit voltage and fill factor and considerably less. The polarity observed in Voc and Isc is consistent with the band bending of a simple Sn02-semiconductor heterojunction energy-band diagram neglecting interface states. The ohmic behavior for (n-p) Sn02-Ge is attributed to the accumulation lay a existing between Sn02 conduction band and Ge valence band at the interface. Copyright © 1978 by The Institute of Electrical and Electronics Engineers, Inc.