Highly Resistive Semitransparent G–aSi–ITO Photodetectors with Graded Energy Band Gaps

Abstract

Nonhydrogenated, undoped semitransparent amorphous silicon thin films exhibit a thickness-dependent Tauc optical energy band gap and form uniquely highly resistive devices with a graded energy band gap. When combined with optically transparent, electrically conductive, and flexible graphene, these highly resistive semitransparent amorphous silicon films with graded energy band gaps offer significant potential for the development of graphene (G)–amorphous silicon (aSi: nonhydrogenated and undoped)–indium tin oxide (ITO) photodetector arrays fabricated on glass. These arrays are promising for future semitransparent optoelectronic applications, such as sensors in displays and see-through or video-through augmented reality (AR)/virtual reality (VR) glasses. Notably, these structures exhibit unique junction characteristics, with the Fermi level pinned at bulk defect states, as well as distinctive photoresponse properties.