Options
2006
Conference Paper
Title
Stability of CIGS minimodules with ZnO:Al films prepared by reactive mid-frequency magnetron sputtering
Abstract
The industrialization of CIGS solar modules in larger scale has raised the demand for production processes for high quality TC0 films. Due to their low cost Zn0:Al films are used. Production is mostly done by sputtering of ceramic Zn0:AI2O3 targets on large scale. Reactive sputtering offers an attractive alternative and has beeil tried out for the production of Zn0:Al front contacts on mini-modules. Variation of deposition parameters has shown that (i) substrate temperature should be as high as possible without causing absorber degradation, (ii) total pressure during deposition should be as low as possible and (iii) the deposition should be carried out at fairly low oxygen partial pressure. At the best deposition parameters tried out a module with an efficiency of 7 % after 1000 hours of damp heat testing without encapsulation was obtained. The damp heat stability of the best films showed a behavior similar to films produced by DC sputtering. While reproducibility is still an issue to be worked on in future the process offers much room for improvements as it can be strongly influenced by slight changes in deposition parameters, allowing for better optical transmission and better damp heat stability for optimized films.
Language
English
Keyword(s)