Energy band diagram of the a-Si:H/c-Si interface as determined by internal photoemission

Abstract

The internal photoemission of electrons from the valence band of crystalline silicon into the conduction band of amorphous hydrogenated silicon has been studied experimentally. The photoemission process in the case of the interface between two semiconductors raises specific problems in the treatment of data, and these are analysed. The results indicate that the energy difference between the amorphous and crystalline valence band edges at the interface is close to zero, and is not affected by the hydrogen-induced widening of the optical gap in amorphous silicon.