Wei-Yu Kong, Guo-An Wu, Kui-Yuan Wang, Teng-Fei Zhang, Yi-Feng Zou, Dan-Dan Wang, Lin-Bao Luo*
Abstract: In this study, we report on the fabrication of a sensitive deep ultraviolet photodetector (DUVPD) by directly transferring multi-layer graphene (MLG) on a commercial n-type beta-gallium oxide (β-Ga2O3) wafer. The as-assembled MLG-Ga2O3 heterojunction device exhibited not only rectifying behavior, but also obvious sensitivity to DUV light illumination (254 nm) with very good stability and reproducibility. The responsivity and electivity were estimated to be 39.3 A/W and 5.92×1013 Jones, respectively, which are much better than most of the Ga2O3 nanostructures based devices ever reported. What is more, further spectral response analysis revealed that the DUVPD was highly sensitive to UV light with wavelength less than 254 nm, but was nearly blind to photons with wavelength longer than 280 nm. Such a spectral selectivity is in good consistence with the operation mechanism. The above results signify that the present simply-structured MLG-Ga2O3 DUVPD will have promising application in future optoelectronic systems.