Sub-band-gap photoconductivity of individual alpha-Si3N4 nanowires

摘要

Single-crystalline alpha-Si3N4 nanowires with diameters of a few tens of nanometres were grown by combustion synthesis, and the I-V characteristics in individual alpha-Si3N4 nanowires upon different light exposure were investigated. The conductance exhibits a sharp and marked rise (about one order of magnitude) upon 254 nm ultraviolet (UV) light exposure; in contrast, it does not respond to a 532 nm green laser. The fast response and recovery as well as the good reversibility between the high and low conductivity states make alpha-Si3N4 nanowires promising candidates for solar-blind photodetectors.