Process development and comparison of various boron emitter technologies for high-efficiency (∼21%) n-type silicon solar cells

This paper shows for the first time a comparison of commercial-ready n-type passivated emitter , rear totally diffused solar cells with boron (B) emitters formed by spin-on coating, screen printing, ion implantation, and atmospheric pressure chemical vapor deposition. All the B emitter technologies show nearly same efficiency of similar to 20%. The optimum front grid design (5 busbars and 100 gridlines), calculated by an analytical modeling, raised the baseline cell efficiency up to 20.5% because of reduced series resistance. Along with the five busbars, rear point contacts formed by laser ablation of dielectric and physical vapor deposition Al metallization resulted in another 0.4% improvement in efficiency. As a result, 20.9% efficient n-type passivated emitter, rear totally diffused cell was achieved in this paper. Copyright (c) 2016 John Wiley & Sons, Ltd.