Other Aspects of the ALILE Process

Usually the poly-Si films on foreign substrates, prepared by the ALILE process, are used as a template (seed layer) for subsequent homo-epitaxial growth of the absorber layer of a poly-Si thin-film solar cell. The highest efficiency 

The poly-Si films obtained by ALILE process always show p-type behavior. On high temperature resistant foreign substrates, the p-type poly-Si can be transferred to n-type poly-Si by overdoping, e.g., by phosphorous diffusion at 950°C [68], This allows for other solar cell configurations (e.g., substrate/ n+-type ALILE seed layer/n-type absorber/p+-type emitter). 

The last two paragraphs show clearly that variations of the standard ALILE process can lead to interesting new results, which offer new promising perspectives. There are probably a lot of other options to vary the standard ALILE process. Therefore, further research is needed to completely utilize the possibilities of this process. 

There is already an excellent fundamental understanding of the ALILE process. However, many important questions remain open. Continuous research is needed to give adequate answers to these questions and to fully exploit the potential of the ALILE process. The upcoming years will show whether this fascinating process can be used in the industrial production of Si thin-film solar cells. 

I like to thank my (partly former) colleagues at the Helmholtz-Zentrum Berlin fur Materialien und Energie (formerly Hahn-Meitner-Institut Berlin) for their contributions during the last years in the context of our research on the ALILE process, in particular J. Berghold (formerly J. Klein), W. Fuhs, O. Hartley (formerly O. Nast), K.Y. Lee, M. Muske, B. Rech, A. Sarikov, J. Schneider and I. Sieber. Especially, the intensive collaboration with J. Schneider and W. Fuhs has provided the basis for this chapter. The research on the ALILE process has been financially supported by the European Commission in the framework of the projects METEOR and ATHLET. I have highly appreciated the collaborations with the project partners and also with other external colleagues. 

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