Characterization of epitaxial film silicon solar cells grown on seeded display glass

We report characterization of epitaxial film crystal silicon (c-Si) solar cells with open-circuit voltages (V_oc) above 560 mV. The 2-um absorber cells are grown by low-temperature (<;750 °C) hot-wire CVD (HWCVD) on Corning^® EAGLE XG^® display glass coated with a layer-transferred (LT) Si seed. The high V_oc is a result of low-defect epitaxial Si (epi-Si) growth and effective hydrogen passivation of defects. The quality of epitaxial growth by HWCVD on seeded glass substrates depends on the crystallographic quality of the seed and the morphology of the growth surface. Complete heterojunction cells consist of glass/c-Si LT seed/ epi n⁺ Si:P/epi n^- Si:P/intrinsic a-Si:H/p⁺ a-Si:H/ITO. Similar devices grown on electronically `dead´ n⁺ wafers have given V_oc ~ 630 mV and ~8% efficiency with no light trapping features. Here we study the effects of the seed surface polish on epi-Si quality, how hydrogenation influences the device character, and the dominant junction transport physics.