Graphene-based deep-ultraviolet photodetectors with ultrahigh responsivity using chemical vapor deposition of hexagonal boron nitride to achieve photogating
Shoichiro Fukushima, Satoru Fukamachi, Masaaki Shimatani, Kenji Kawahara, Hiroki Ago, Shinpei Ogawa
Abstract
This study presents high-responsivity graphene-based deep-ultraviolet (DUV) photodetectors using chemical vapor deposition (CVD)-hexagonal boron nitride (h-BN) photogating. To improve the DUV photoresponse, h-BN was used as a photosensitizer in graphene field-effect transistors (GFETs). The h-BN photosensitizers were synthesized using CVD and then transferred onto a SiO 2 /Si substrate. The behavior of h-BN irradiated with DUV light was investigated using cathodoluminescence and UV–VIS reflectance. Under 260 nm light, it exhibited a clear photoresponse with an ultrahigh responsivity of 19600 AW -1 , which was 460% higher than a GFET device without h-BN photosensitizers. A noise equivalent power of 3.09×10 −13 W/Hz 1/2 was achieved.