HIGH-EFFICIENCY THIN POLYCRYSTALLINE SILICON SOLAR-CELLS

New technologies for high efficiency silicon solar cells have been investigated using cast polycrystalline silicon substrates which are expected to realize much reduction of cost in the near future. The highest conversion efficiency of 16.4% has been achieved for a 10cm square polycrystalline silicon solar cell with a double layer anti-reflection coating formed on the grooved surface by the reduction of surface reflectance in addition to surface passivation and electrode area reduction technologies which had been developed previously. The variation of cell performances with diffused layer structures of N+ and with front side electrode structures have been clarified through numerical computer simulation. As a result, capabilities of improvement in cell performances have been revealed.