Amorphous Silicon Based MIS Structures for Solar Cells Applications: Electrical Considerations

This paper suggests a dc analysis of an amorphous silicon based Metal-Insulator-Semiconductor (MIS) structure for solar cells applications. Since it has been reported that biasing the cell was one of the techniques that improves conversion efficiency of MIS transistor-based solar cells, it tries to get accurate comprehension on the electrical optimization side of the structure to allow accurate superposition of the light effect. The detailed model is based on an exponential distribution of density of states. The electrical and physical properties are discussed and expressions of the charge densities are derived. Investigations on the evolution of the potential profile at the interface insulator/amorphous silicon and of the gate voltage reveal the conditions of appearance of the accumulation layer corresponding to the large variation of the conduction electrons density.