High-performance self-driven near-infrared photodetector based on single-walled carbon nanotube/graphene/Al2O3/InP

Carbon nanotube (CNT) is one of the typical materials for near-infrared photodetectors. Combining its ultra-high mobility, excellent infrared absorption, and suitable energy band structure with graphene and semiconductors, it greatly improves the photodetector performance. This paper reports a self-driven near-infrared photodetector of single-walled carbon nanotubes (SWCNTs)/single-layer graphene/Al2O3/P-type InP structure, the photocurrent of the device is greatly improved with the help of SWCNTs, and the Al2O3 layer improves the Schottky barrier between InP and graphene, which can suppress the carrier recombination on the semiconductor surface. This device structure exhibits a highly sensitive photoresponse at 808 nm, and at zero under the bias condition, the responsivity reaches 154.3 mA·W−1, and the detection rate reaches 1.27 × 1012 Jones. It has a fast response time of microsecond level, and can meet the detection requirements in the mid-frequency range. This result is expected to provide ideas for further optimization on single-walled carbon nanotubes in near-infrared photodetectors.