Growth and Optical Properties of ZnSe Nanofilms Obtained from Modified Ammonia-free Chemical Bath Solution

ZnSe nano thin films were obtained with chemical bath deposition in an modified aqueous alkaline solution in which ammonia was eliminated from the complexing agent in our present work. The as-deposited films are transparent, specula reflective and homogenous. Energy-dispersive X-ray spectroscopy indicated that films were in near stiochiometric Zn:Se ratio. Measured by spectroscopic ellipsometry, thickness of 50~370nm film can be obtained, the ZnSe were in nano-films, morphology and the film formation process discussion indicated that the film grow through nano-cluster by nano-cluster deposition rather than ion by ion mechanism. Absorption of the annealed films in visible light area indicated that bandgap is around 2.8eV for the annealed ZnSe film obtained from modified ammonia free solutions, corresponding to the standard band gap for bulk ZnSe materials.