High efficiency gallium doped and boron doped multicrystalline silicon solar cells

Recently, the mono- and the multicrystalline (mc) silicon wafer technology have dominated the photovoltaic market because of its advantage of conversion efficiency, reliability and cost in comparison with other technology. Especially the market share of mc-Si solar cell seems to be more than 50% in 2002. We have been investigating the mc-Si photovoltaic solar cells to reduce the cost for many years. The improvement of the solar cell efficiency has a drastic effect on the reduction of the solar cell cost. The improvement of mc-Si material especially boron related defects which decorate the band gap with various defects including well-known iron-boron pairs is very important issue for the higher cell efficiency. In this paper, we have investigated an approach that leads to an efficiency improvement by the substitution of boron (B) by gallium (Ga) as the dopant material.