Micro-Raman Study of Orientation Effects of CuxSe-Crystallites on Cu-rich CuGaSe2 Thin Films

The structural properties of copper selenide (CuxSe), formed as a secondary phase on the surface of CuGaSe2 films grown under Cu-rich conditions on GaAs (100) substrates, were studied by micro-Raman spectroscopy. Raman bands at 45 and 263cm−1, observed on crystallites dispersed on the CuGaSe2 film, are in agreement with the Raman modes of CuSe and Cu2Se. Polarization- and angular-dependent micro-Raman measurements reveal that the CuxSe-crystallites are grown with a preferential orientation on the CuGaSe2 surface.