HIGH PRODUCTIVITY ION IMPLANTATION FOR 19 EFFICIENT INDUSTRIAL SILICON SOLAR CELLS

摘要

In order to achieve grid parity and reduce the Levelized Cost Of Electricity (LCOE), future industrial solar cellproduction will have to achieve higher efficiencies. In order to improve efficiencies of the current phosphorus emitter cells,there is a focus on tailoring of the phosphorus profile, as well as improved uniformity, repeatability, and tailoring of the nearsurface phosphorus dose. Ion implantation systems can provide these performance capabilities. Historically, productivity hasbeen an issue for ion implantation applied to solar cells. Intevac has developed a novel high productivity ion-implantationtool capable of 2400 wafer per hour throughput for phosphorus and boron implants. With this tool, we demonstrate highefficiency cells with improved blue response and narrower distribution of efficiencies over standard diffused phosphorusemitter cells. We show average cell efficiencies of 18.8% with up to 19% cells in initial customer qualification tests of theIntevac implantation tool. These efficiencies represent a clear performance improvement over diffusion. Further optimizationis expected to increase this improvement.