Experimental and theoretical investigations of a new potential barrier due to sharp a-Si/c-Si heterointerfaces buried in the solar cell emitter

Several new concepts to increase the conversion efficiency of solar cells have been presented over the last few years. One possibility is the multi-interface novel device solar cell with a highly doped amorphised substructure inserted in the emitter. This active nanostructure is created by P ion implantation followed by an adequate thermal treatment necessary to form two sharp a-Si/c-Si heterointerfaces. After an incomplete initial thermal treatment at 500°C, dark current–voltage (I–V) characteristics were measured after each of several complementary thermal treatments. In this paper, we show that the classical two-diode model has to include a voltage reduction resulting from the two low–high-type interfaces in order to correctly fit the experimental curves.