STRESS-INDUCED RAMAN FREQUENCY-SHIFT IN CUINSE2 THIN-FILMS PREPARED BY LASER-ABLATION

Thin films of CuInSe2 have been prepared by laser ablation using a Nd:YAG laser at substrate temperatures up to 450 degrees C. Raman scattering experiments have shown that the frequency of the Al phonon mode for these films shifts markedly to higher frequencies similarly with CuInSe2 single crystals under compression. The existence of compressive stress in the films has been confirmed by observing the bending of a cover glass used as substrate. The magnitude and temperature dependence of the stress estimated from the frequency shifts agree with those determined from the degree of bending.