One-dimensional self-consistent solution of modulation doped nanocrystalline/crystalline Si heterojunctions

A kind of modulation doped structure of n-type nanocrystalline hydrogenated silicon (nc-Si:H) film with intrinsic nc-Si:H layer with p-type bulk Si 〈100〉 substrate was proposed. The numerical self-consistent solutions of one-dimensional Schrödinger and Poisson equations along the direction normal to the heterojunction were performed to calculate the distribution of electron density and profiles of conduction-band as a function of ionized donor concentration in doped film, thickness of intrinsic layer, and other device parameters in the junctions. The calculated results are shown to be in agreement with experimental data. The relation of mobility vs sheet density of two-dimensional electron gases under different scattering mechanisms was analyzed. The obtained consequences may be used to evaluate optimum design for the modulation doped nc-Si:H-based devices.