Polyx multicrystalline silicon solar cells processed by PF+ 5 unanalysed ion implantation and rapid thermal annealing

Rapid thermal annealing of damage induced by implantation in silicon can be a cost effective technology for the processing of terrestrial solar cells as compared to classical furnace or pulsed laser annealing. Unfortunately, drawbacks as poor bulk lifetime or low open-circuit-voltage occur as well. We have attempted to overcome these limitations for POLYX multicrystalline cast silicon grown by CGE (France) by keeping the annealing temperature of the phosphorus doped layer as high as 800 °C (to ensure a good crystalline quality and a high dopant activation) while being less than 900 °C (to minimize the effect of degradation of the base properties). The purpose of the present work is to investigate the I-V characteristics of the cells and to compare to those obtained with classical furnace annealing or with classical diffusion process.