A novel method has been developed for the preparation of copper‐indium‐diselenide (CIS) thin films. The method comprises of elemental deposition of Cu, In, and Se layers followed by a CIS compound formation process which does not involve any H2Se gas. The process has led to the formation ofp‐type CIS films which have proper stoichiometry and grain sizes on the order of 1 &mgr;m. The best solar cell fabricated on this material had an active area conversion efficiency of 10.2% withVoc=0.427 V,Jsc=37.41 mA/cm2, and FF=0.641.