Analysis of electron-beam crystallized large grained Si films on glass substrate by EBIC, EBSD and PL

摘要

The properties of electron-beam crystallized, large-grained silicon layers of about 10 μm thickness on glass have been studied by combining EBIC, EBSD and photoluminescence. It is found that most grains are free of dislocations. From a detailed analysis based on the dependence of EBIC collection efficiency on beam energy we conclude that the recombination properties of the layers are mainly determined by the bulk diffusion length. The estimated bulk diffusion length in the dislocation-free layer regions is in the range of roughly 5 – 7 μm, depending on the recombination velocity assumed for the rear surface. In dislocated regions the diffusion length drops to 1 μm or less. Close to some twin boundaries, an unsusual improvement of the electrical layer properties has been observed. In addition, wave-like inhomogeneities of the layer properties have been established, resulting probably from instabilities during the crystallization process.