High efficiency large area n‐type front junction silicon solar cells with boron emitter formed by screen printing technology

In this paper, we report on commercially viable screen printing (SP) technology to form boron emitters. A screen‐printed boron emitter and ion‐implanted phosphorus back surface field were formed simultaneously by a co‐annealing process. Front and back surfaces were passivated by chemically grown oxide capped with plasma‐enhanced chemical vapor deposition silicon nitride stack. Front and back contacts were formed by traditional SP and firing processes with silver/aluminum grid on front and local silver back contacts on the rear. This resulted in 19.6% efficient large area (239 cm²) n‐type solar cells with an open‐circuit voltage V_oc of 645 mV, short‐circuit current density J_sc of 38.6 mA/cm², and fill factor of 78.6%. This demonstrates the potential of this novel technology for production of low‐cost high‐efficiency n‐type silicon solar cells. Copyright © 2014 John Wiley & Sons, Ltd.