Photodetectors based on controllable growth of large-area graphene films

Abstract

In this work, plasma-enhanced chemical vapor deposition method has realized large-area controllable growth of graphene. Thegraphene field effect transistor photodetectorhas been designed and its electrical and photoelectric properties were analyzed. The results show that graphene exhibits good electrical properties in field effect transistors with carrier mobility of 1649 cm−2·V−1•S−1 and conductivity of 7.4 × 104 S/m. The device also shows broad photodetection spectral range from 400 nm to 700 nm. The maximum photo-generated current of the device can reach to mA grade, and the photoresponsivity is 250 A•W−1, 75 A•W−1 and 58.3 A•W−1 at the wavelength of 405 nm, 515 nm, and 650nm, respectively. Meanwhile, the maximum photoconductive gain and detectivity are 1.6 × 1011, 1.3 × 1011 Jones obtained at the wavelength of 405 nm respectively. The results of this work demonstrate that the graphene can be a promising candidate for efficient optoelectronic devices, such as transparent electrodes, opticalmodulator, polarizer, surface plasmonic devices andphotodetectors.