Ion implanted boron emitter N-silicon solar cells with wet oxide passivation

An ion implanted boron emitter silicon solar cell is demonstrated. By using appropriate annealing condition, the implanted dopants and damage introduced by the implantation can be activated and repaired, respectively. Both the rapid thermal annealing (RTA) and furnace annealing were investigated within this work. For the surface passivation and the antireflection coating, the wet oxide (SiO₂) was grown during the furnace annealing step. Since the wet oxidation process has about one order of magnitude faster than the dry oxidation process, it could be a suitable technology for industrial silicon solar cell processing. The rapid thermal annealing with various temperatures and annealing time were also investigated. The open-circuit voltage increased with increasing the temperature and time of the RTA process. The planar p⁺nn⁺ solar cell with wet oxide passivaiton achieves the Voc of 0.631 V and the efficiency of 15.43%.