EFFECTS OF STRAIN ON THE GROWTH AND PROPERTIES OF CUINSE2 EPITAXIAL-FILMS

CuInSe2 films have been grown on both GaAs(0 0 1) and In0.29Ga0.71As p seudo-lattice-matched substrates by solid-source molecular beam epitax y and the effects of strain on the properties of epitaxial films have been investigated. For CuInSe2 epitaxial films grown on GaAs(0 0 1), t he intensities of excitonic emissions become stronger and the line wid ths of the predominant defect-related emissions become smaller on incr easing the thickness of the films from 0.4 to 2 mu m, suggesting that the defect density decreases with the film thickness. Drastic improvem ents in optical and transport properties have been achieved by using I n0.29Ga0.71As pseudo-lattice-matched substrates; free-exciton emission s were predominantly observed, indicating that high-quality CuInSe2 ep itaxial films have been grown by controlling the misfit strain between the substrates and the epitaxial films.