Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6457496 | Solar Energy Materials and Solar Cells | 2017 | 7 Pages |
â¢Development of both boron and phosphorus doped poly-Si/SiOx contacts featuring film thicknesses below 40 nm.â¢Determination of optical properties of poly-Si and quantification of optical absorption losses in poly-Si.â¢Solar cell featuring top/rear poly-Si contacts yields Voc=710 mV and FF>81%.
Passivated contacts based on low-pressure chemical vapor deposited (LPCVD) heavily-doped poly-Si and a thin SiOx layer are explored for the application in an interdigitated back contact (IBC) solar cell. The poly-Si/SiOx contacts are realized by applying wet-chemically grown SiOx tunnel layers and amorphous Si (a-Si) layers doped via ion implantation that are subsequently transformed into poly-Si/SiOx contacts by a high temperature step. The impact of doping species, ion dose, and poly-Si thickness on the surface passivation of such contacts is studied. Excellent J0 values down to 4.5Â fA/cm2 were measured for n+-poly-Si contacts, while J0 values as low as 22Â fA/cm2 were obtained for p+-poly-Si contacts. Solar cells with top/rear poly-Si contacts were processed and Voc values up to 709Â mV and FF values above 81% were measured. Furthermore, the upper bound for the parasitic absorption losses in 10-40Â nm thick poly-Si films was quantified to be about 0.5Â mA/cm2 per 10Â nm poly-Si layer thickness.