Real Time Observation of the Directional Solidification of Multicrystalline Silicon: X-ray Imaging Characterization

Directional solidification of multicrystalline silicon for photovoltaic applications is investigated by means of synchrotron X-ray imaging techniques at the European Synchrotron Radiation Facility. Our experimental device combines two complementary modes: X-ray radiography imaging giving information on the dynamical evolution of the solid/liquid interface and X-ray topography giving information on the grain structure and phenomena occurring during the solidification process such as strains and twinning. In this paper, we report on the experimental details of the developed device and on some preliminary results obtained by using both imaging techniques.