INNOVATIVE APPROACHES TO IMPROVE THE CHARACTERISTICS OF MIS/IL AND MINP SILICON SOLAR CELLS.

High-efficiency MIS/IL and MINP silicon solar cells have been fabricated using innovative approaches to form the ultrathin tunneling insulator film. Both the output I-V characteristics and the stablity of the solar cells are improved considerably when the conventional ultrathin SiO//2 film is treated with ammonia at low temperature and low pressure or is replaced by an ultrathin tunneling insulator film which is formed directly under ammonia ambient at low temperature and low pressure. With these approaches the conversion efficiency of the MIS/IL or MINP silicon solar cells has been improved greatly compared with that of conventional MIS/IL or MINP silicon solar cells. Short-circuit current densities of 35. 2 mA/cm**2 for MIS/IL silicon solar cells and 37. 6 mA/cm**2 for MINP silicon solar cells (AM1. 5, 100 mW/cm**2, 25 degree C) have been achieved when single-layer PECVD silicon nitride is used as the antireflection coating and CZ silicon as the substrate. 17 refs.