Key technologies for improvement of multicrystalline silicon solar cel
ls investigated at Kyocera are described in this paper. Main key techn
ologies are (1) optimization of emitter structure, (2) reduction of su
rface reflectance, (3) bulk and surface passivation, and (4) preparati
on of electrode. Conversion efficiencies of 16.5% and 16.4% have been
obtained for multicrystalline silicon solar cells with cell areas of 1
0 x 10 cm(2) and 15 x 15 cm(2), respectively, using substrates made by
the casting method. Higher conversion efficiencies are expected to be
obtained by further investigation of the above-mentioned key technolo
gies.