The electrical, optical properties of CdTe polycrystalline thin films deposited under Ar-O2 mixture atmosphere by close-spaced sublimation

In order to further decrease the fabrication cost, a technology of close-spaced sublimation under Ar-O2 mixture atmosphere has been studied. A deposition method of CdTe thin films on smooth glass substrates has been developed. The structural characteristics of CdTe films, which are deposited on glass substrate and CdS/SnO2:F/glass substrate, have been compared. The effects of oxygen partial pressure on the structure and characteristics have been investigated and the preferred orientation was quantificationally studied, which shows that there are the same structures of CdTe thin films on both kinds of substrates, if these films are deposited in an appropriate close-spaced sublimation process. Then the optical and electrical properties of CdTe films on glass substrates are studied, and the effects of post-treatment on the properties are observed. These results have been used to prepare CdS/CdTe/ZnTe:Cu solar cells.