We developed a poly-Si solar cell with a novel structure for terrestrial ap
plications. Since the grain boundary (GB) in the polycrystalline silicon (p
oly-Si) reduces the conversion efficiency of the poly-Si solar cell. to min
imize the GB effect, we performed a preferential grain boundary etching. PO
Cl3 n-type emitter doping, and then an tin-doped indium-oxide (ITO) film gr
owth on poly-Si. An rf-magnetron sputter-grown film was used for easy forma
tion of the top electrode. The ITO films showed a resistivity of 1.14 x 10(
-4) Omega -cm and a transmittance of 90.5 70 for a wavelength of 594 nm. Th
e ITO films served riot only as top electrodes but also as effective AR coa
ting layers. The ITO film properties were strongly influenced by the prepar
ation temperatures.. A substrate temperature of 400 degreesC gave the highe
st conversion efficiency for the poly-Si solar cells. With well-fabricated
poly-Si solar cells, we were able to achieve a conversion efficiency as hig
h as 15 % at an input power of 20 mW/cm(2).