A Broadband Photoelectronic Detector in a Silicon Nanopillar Array with High Detectivity Enhanced by a Monolayer Graphene

To meet the fast-growing need for broad applications in remote sensing, novel optoelectronic devices with high detectivity in full bands and room temperature operation are urgently desired. This paper reports our progress in developing a specially designed photovoltaic detector by integrating a monolayer graphene onto a silicon-based nanopillar array standing on a p-n junction. Optoelectronic measurements of the fabricated detectors show that the monolayer graphene plays a critical role in device performance. Compared with the one without the graphene covering, the new device demonstrates significant improvements in the specific detectivity of 1.43 x 10(13) Jones and the responsivity exceeding similar to 10(6) V/W with a reduced leakage current corresponding to a quantum efficiency of 74.8% at 860 nm wavelength. Moreover, such sensing performance remained unaffected over the entire band from 450 to 1100 nm at room temperature, which is suitable for broadband imaging applications.

Automated summary

This study reports a specially designed photovoltaic detector by integrating monolayer graphene onto a silicon-based nanopillar array, achieving the requirement of high detectivity in full bands at room temperature. The research results show that graphene plays a critical role in improving device performance.