Laser-induced synthesis of thin CuInSe2 films

Abstract
Thin films of CuInSe2 are synthesized by laser irradiation of Cu‐In‐Se sandwiches in 1:1:2 atomic proportion. Using transmission electron microscopy (TEM), electron diffraction, and optical spectrometry, the presence of semiconducting ternary compound CuInSe2, with the chalcopyrite structure, is strongly evidenced in all the irradiated samples, supported or not, with no other phases observed. For glass‐supported films, the optical absorbance characteristic of a uniformly transformed region indicates a direct optical band gap of (0.95±0.10) eV. Crystallites obtained on free‐standing films (i.e., supported on TEM grids) can reach 20 μm in dimension.