TEM Studies of High-Efficiency CdTe Solar Cells on Commercial SnO_2/Soda-Lime Glass

摘要

The microstructure of high-efficiency CdTe solar cells on commercial SnO_2/soda-lime glass was investigated by scanning transmission electron microscopy. The CdTe solar cells have a structure of soda-lime glass/SnO_2/ZTO/CdS:O/CdTe. We found no interdiffusion between the SnO_2 layer and ZTO layer. Weak diffusion of Zn from the ZTO layer into the CdS:O layer was observed; however, the diffusion was not uniform. Interdiffusion also occurred at the CdTe/CdS:O interface. In the back-side of the CdTe, a thin layer of Te was found, which formed during the nitric-phosphoric etching. In addition, a very thin layer of CdHgTe was observed at the CdTe/Te interface.