Effect of post deposition annealing of printed AlOx film on PERC solar cells

AlO_x provides excellent passivation on p-type silicon surface and has successfully implemented to high efficiency Passivated Emitter and Rear Cell (PERC) solar cells in recent years. Generally, AlO_x is deposited by using plasma enhanced chemical vapor deposition (PECVD) or atomic layer deposition (ALD). In our work, in contrast, a novel printable AlO_x paste is applied to form rear passivation layer of PERC cells. In this paper, we focus on illustrating the effect of post deposition annealing (PDA) on PERC cells. Using proper PDA, an average efficiency of 20.0% with the best efficiency of 20.1% is achieved. It demonstrates the feasibility of using this printable AlO_x paste. And more important is that this printable AlO_x paste can be easily integrated to existing production line with minimum additional capital cost for equipment.