European Commission
A EUROPEAN PROJECT SUPPORTED THROUGH
THE SEVENTH FRAMEWORK PROGRAMME
FOR RESEARCH AND TECHNOLOGICAL DEVELOPMENT
agence de communication Lyon

On the nature of striations in n-type silicon solar cell.
A. Le Donne, S. Binetti, V. Folegatti , G. Coletti


Abstract
In n-type Czochralski silicon (Cz-Si) wafer, swirl shaped regions with low lifetime (known as striations) can cause degradation up to 1% absolute or even more in homojunction industrial solar cells. Nevertheless, the nature of the defects responsible for the occurrence of these striations is still unclear. In this work, n-type Cz-Si solar cell precursors cut from industrial size ingots with different feedstock quality and oxygen content were analyzed by microwave photo-conductance decay and photoluminescence in order to investigate the nature of such defects. The results demonstrate that the defects responsible for the occurrence of striations are oxide nanoprecipitates formed during the high temperature steps for the solar cell realization, due to the presence of grown-in oxygen nuclei.

 

Applied Physics Letters, 2016, Volume 109
doi: dx.doi.org;10.1063/1.4959558