Growing Cu \textsubscript2 ZnSnS \textsubscript4 Thin Film at Low Temperature Using a New Improved Configuration of Close-Distance CVD Technique
Résumé
Abstract This study presents a new possibility to deposit the polycrystalline Cu 2 ZnSnS 4 (CZTS) thin film at low temperature using an improved close-distance chemical vapor deposition reactor. Firstly, a theoretical study is conducted to predict the iodine pressure ( P I2 ) and the substrate temperature ( T s ) as the optimal conditions for the deposition of CZTS. The theoretical model is based on the minimization of the Gibbs energy of the Cu-Zn-Sn-S-I chemical system. An experimental study is realized, and the predicted optimal conditions to obtain quasi-stoichiometric depositions are tested. The X-ray diffraction, Raman spectroscopy, energy dispersive spectroscopy, scanning electron microscopy, and UV−vis−NIR spectroscopy are used to analyze the thin films elaborated at substrate temperatures of T s ~=~400 and 550~^\circC for iodine pressure P I2 ~=~0.03~\texttimes~10 5 ~Pa. With the help of the thermodynamical calculations, the results show that it is possible to grow a good quality CZTS thin film at a low substrate temperature of 400~^\circC.