The Relation Between the Bandgap and the Anisotropic Nature of Hydrogenated Amorphous Silicon PROJECT TITLE :The Relation Between the Bandgap and the Anisotropic Nature of Hydrogenated Amorphous SiliconABSTRACT:The bandgap of hydrogenated amorphous silicon (a-Si:H) is studied using a unique set of a-Si:H films deposited by means of three different processing techniques. Using this large collection of a-Si:H films with a wide variety of nanostructures, it is demonstrated that the bandgap has a clear scaling with the density of both hydrogenated divacancies (DVs) and nanosized voids (NVs). The presence of DVs in a dense a-Si:H network results in an anisotropy in the silicon bond-length distribution of the disordered silicon matrix. This anisotropy induces zones of volumetric compressed disordered silicon (larger fraction of shorter than longer bonds in reference to the crystalline lattice) with typical sizes of ∼0.8 up to ∼2 nm. The extent of the volumetric compression in these anisotropic disordered silicon zones determines the bandgap of the a-Si:H network. As a consequence, the bandgap is determined by the density of DVs and NVs in the a-Si:H network. Did you like this research project? To get this research project Guidelines, Training and Code... Click Here facebook twitter google+ linkedin stumble pinterest New Generation Transparent LPCVD ZnO Electrodes for Enhanced Photocurrent in Micromorph Solar Cells and Modules High-Efficiency, Multijunction nc-Si:H-Based Solar Cells at High Deposition Rate