Thin-film solar cell

Abstract

A thin-film solar cell includes a thin active layer of high purity material having opposed front and rear surfaces for light-to-electricity conversion, a structure for supporting the thin active layer, and a rear electrode in contact with the rear surface of the active layer. The supporting structure includes a supporting substrate of a low purity material having opposed front and rear surfaces, on the front surface of which the rear surface of the active layer is disposed, and an insulating barrier layer interposed between the front surface of the supporting substrate and the rear surface of the active layer. The barrier layer prevents impurities in the supporting substrate from diffusing into the active layer. Since the supporting substrate comprises a low purity material, the quantity of the expensive high purity material can be reduced by reducing the thickness of the active layer, resulting in low production costs. Since the supporting substrate is present on the rear surface of the active layer, a surface electrode disposed on the front surface of the active layer is exposed. Therefore, when a solar cell module is fabricated using a plurality of the solar cells, a wire bonding process for connecting adjacent solar cells is easily carried out.