Influence of Deposition Parameters on the Morphology of CdTe Films and on the Performance of CdTe Solar Cells
Tóm tắt
For industrial CdTe solar cell production, thin, dense and pinhole-free films have to be deposited at high rates. Using a close-to-industrial close space sublimation (CSS) process, we deposited CdTe films at different temperatures and rates. The morphology of these films was analyzed by scanning electron microscopy (SEM) and x-ray diffraction (XRD). The measurements show the size, size distribution and orientation of the grains to strongly depend on deposition temperature and rate. A suitable combination of these parameters yields large grains of about 3 microns diameter even for deposition temperatures below 750 K and at high deposition rates of 3 microns per minute. The interplay of CdTe layer morphology and solar cell performance is elucidated employing a TCO-CdS-CdTe-Mo film sequence for complete solar cells.
Tài liệu tham khảo
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