High-Efficiency n-Type Si Solar Cells With Novel Inkjet-Printed Boron Emitters

Formation of a well-passivated boron emitter for mass production of low-cost and high-efficiency n-type silicon solar cells is a major challenge in the photovoltaic industry. In this letter, we report on a novel and commercially viable method, inkjet printing, to create boron emitters. Phosphorus diffusion was used on the rear to form a back-surface field in conjunction with chemically grown oxide/silicon nitride (SiNx) stack on the front and back for surface passivation. Finally, front and back screen-printed contacts were formed through the dielectric stacks to fabricate large-area (239 cm(2)) n-type cells. This technology resulted in 19.0%-efficient p(+)-n-n(+) cells with a V-oc of 644 mV, a J(sc) of 38.6 mA/cm(2), and a fill factor of 76.3%. This demonstrates for the first time the promise of boron-inkjet-printing technology for low-cost and high-performance n-type Si cells.