Device Performance Enhancement by Surface Passivation of GaAs Nanowires: A Quantitative Study

Synthetic nanomaterials such as semiconductor nanowires (NW) will play an essential role in the future of electronics, photonics and energy-harvesting due to the unique electrical and physical properties arising from their quasi one-dimensional (1- D) structure. However, many challenges still remain in controlling and understanding their fundamental properties as well as quantifying the effects of surfaces on the NW device performance. In this proposal, we aim to investigate the intrinsic transport properties, their diameter-dependence and surface effects of GaAs NWs utilizing a complementary optical and electrical study. This unique technique would enable a direct and quantitative assessment of the NW carrier transport characteristics, such as the field-effect mobility, minority carrier diffusion length and effective lifetime, which are important design parameters for the NW devices. We will then explore various surface functionalization schemes to passivate the NW surface for enhanced material properties for high-performance device applications.