High-performance graphene/InSb heterojunction mid-infrared photogated diode

Herein, we developed a high-performance graphene/InSb heterojunction mid-infrared (IR) photogated diode for IR image sensors. We achieved low noise owing to a significant reduction in the dark current and high responsivity, which is attributed to the graphene/InSb heterojunction diode structure and the photogating effect. The detection performance of the proposed device is better than that of conventional graphene-based IR sensors in the mid-infrared region of 3–5 μm. These results indicate that the combination of a simple graphene/InSb heterojunction and the photogating effect can produce IR image sensors with better detection performance than existing IR sensors.