Infra-red studies of oxygen adsorbed on evaporated germanium films

The spectra of four infra-red active species between 550 and 4000 cm–1 have been observed. A band which appears after exposure of germanium to oxygen for up to 10–6 Torr min has been identified tentatively as the O ion adsorbed over bare germanium, a second pair of bands at 690 and 780 cm–1 after exposures between 10–6 and 10–1 Torr min are identified with a surface Ge—O—Ge group. Similarty in the logarithmic growth of the bulk oxide on germanium and the development of a band at 840 cm–1 allow identification of interstitial oxygen, and a band at 750 cm–1 confirms the existence of Ge—O– in the surface during the growth of the bulk oxide layer as postulated by Bennett and Tompkins.