Effect of Implanted Phosphorus Profile on iV(oc) Variations During Firing Process of n-type Silicon

Electrical activation of implanted phosphorus can be carried out simultaneously with boron dopants at high temperatures or separately at lower temperatures. In this study, we investigate the effect of high and low-temperature annealing processes for dopant activation following the phosphorous implantation process in n-type c-Si. Symmetrically implanted wafers are activated at 875 degrees C (low temperature) and 1050 degrees C (high temperature) and subsequently coated with PECVD SiNx:H. iV(oc) values of the samples activated at 1050 degrees C significantly decrease while those for the samples activated at 875 degrees C increase at a typical firing peak temperature which is generally applied for fire-through contact formation. We also show a strong dependence of iV(oc) values of phosphorous implanted and unimplanted c-Si, which are activated at both high and low temperatures, on peak firing temperature.