Characterization of 3-Inch Solar Cells Fabricated from Granular Silicon Obtained in a Fluidized-Bed Reactor

Industrial feasibility of a solar-grade silicon material for use in terrestrial solar cells is demonstrated through the fabrication of practical size, 3'' diameter, solar cells. The granular silicon prepared in a fluidized-bed reactor consumes less energy than the current Siemens process. A polycrystalline ingot obtained by the Czochralski method is described as a function of ingot length in terms of electrical properties and solar cell performance. Impurity gettering is also attempted through the application of a phosphorus diffusion process. The possibility of realizing a conversion efficiency higher than 8% for an entire ingot is revealed.