AMPS modeling of nanocrystalline Si p-layer in a-Si nip solar cells

. This paper reports numerical simulations for the impact of a wide bandgap p-type hydrogenated nanocrystalline silicon (nc-Si:H) on the performances of a-Si based component solar cells, using Analysis of Microelectronic and Photonic Structures (AMPS) computer model developed at Penn State University. The effects of band offset and potential barrier formed at the interfaces of player with i-layer and ITO front contact were also investigated. The simulated results show that 1) with increasing bandgap of p-nc-Si:H (E_gp), the V_oc increases beyond 1 V, then decreases, due to the band offset at the p/i interface, which also leads to an anomalous illuminated I-V characteristics with a bending close to the open circuit point; and 2) the front contact barrier plays a similar role to hinder the hole collection and may cause the illuminated I-V curve to bend seriously.