Characterization of High Efficiency Heterojunction Thin Rib-Si Solar Cells

Conversion efficiencies of 20.2% and 19.9% (1 cm
²
) were obtained for 100 µm and 50 µm-thick Rib-Si solar cells, respectively. At present, the interface defect density is estimated to be 5x10
¹⁰
to 1x10
¹¹
/cm
²
. It was found that an open-circuit voltage exceeding 730 mV can be obtained when the effective carrier lifetime is 1 ms or more for a wafer thickness of
$100\ \mu\mathrm{m}$
. The electroluminescence efficiency of the Rib solar cell was 0.15%. The relationship between electroluminescence efficiency and the thickness of Si wafer was analyzed theoretically and compared with experimental results.