Films were grown, by using molecular beam epitaxy, onto pseudo lattice-matched substrates that consisted of a 1-thick Ga0.71In0.29As layer on a linearly compositionally graded Ga1-xInxAs buffer (where x was between 0 and 0.29); which had in turn been grown onto GaAs (001). The properties of these films were compared with those of films which had been grown directly onto GaAs (001). High-resolution X-ray diffraction analysis of CuInSe2 which had been grown onto pseudo lattice-matched substrates indicated a substantial reduction of the residual strain in the CuInSe2 films. A photoluminescence spectrum, that was dominated by sharp free-exciton emissions, was observed for the first time from these films. This reflected an appreciable improvement in crystalline quality, and a substantial reduction in the point defect density.

S.Niki, P.J.Fons, A.Yamada, T.Kurafuji, S.Chichibu, H.Nakanishi, W.G.Bi, C.W.Tu: Applied Physics Letters, 1996, 69[5], 647-9