Characterization and optimization of the interface quality in amorphous/crystalline silicon heterojunction solar cells

We report on the influence of the interface quality on the output characteristics of amorphous/crystalline silicon heterojunction solar cells. A simulation study shows that interface states strongly influence the open circuit voltage and thus the solar cell efficiency. The interface quality, characterized by photoluminescence measurements, is optimized by varying the deposition conditions of the thin amorphous silicon film. The electronic properties of the amorphous emitter on the crystalline silicon substrates were investigated by photoelectron yield spectroscopy. A variation of the deposition conditions leads to a change in the effective interface recombination and also in the electronic structure of the amorphous silicon layer.