Morphology and photoluminescence study of CdTe films deposited by close-spaced sublimation in argon ambient

Most researchers have applied expensive He gas as the ambient in close-spaced sublimation and have received good results. But considering the cost of Helium, it is significant to study the effects of another cheap inert gas on CSS CdTe films. In this paper, CdTe thin films have been deposited on CdS thin films by CSS in Ar and Ar+O/sub 2/ ambient. The microstructure, morphology and photoluminescence spectra of CdTe films for as grown and annealed samples have been studied. The difference of PL spectra between CdTe surface and CdTe/CdS interface has been investigated. It has been found that Ar+O/sub 2/ atmosphere is helpful for (111) preferential orientation. CdCl/sub 2/ is found to benefit for grain growth and better crystallinity. The PL spectra have demonstrated that 380/spl deg/C thermal treatment is most helpful to form complete grains. 13.38% efficiency has been achieved for this kind of solar cell.