Epitaxial films were grown, by means of molecular beam epitaxy, using a substrate temperature of 450C and the vacancy-type defects which governed the properties of the films were characterized. Films which were grown under excess In-flux conditions tended to exhibit a non-ideal crystalline quality in that the films were highly compensated, with a high density of twins. Post-growth annealing of the films in air appreciably reduced the twin density, as well as the degree of compensation. This suggested that there was a strong correlation between Se-vacancies and the twin density. Preliminary results showed that the in situ incorporation of O during molecular beam epitaxial growth made it possible to reduce the twin density. It was suggested that this was because O substituted for Se vacancies.

Control of Intrinsic Defects in Molecular Beam Epitaxially Grown CuInSe2 S.Niki, P.J.Fons, Y.Lacroix, K.Iwata, A.Yamada, H.Oyanagi, M.Uchino, Y.Suzuki, R.Suzuki, S.Ishibashi, T.Ohdaira, N.Sakai, H.Yokokawa: Journal of Crystal Growth, 1999, 201-202, 1061-4