High-Performance Photodetectors Based on Semiconducting Graphene Nanoribbons

Abstract

The inherent zero-band gap nature of graphene and its fast photocarrier recombination rate result in poor optical gain and responsivity when graphene is used as the light absorption medium in photodetectors. Here, semiconducting graphene nanoribbons with a direct bandgap of 1.8 eV are synthesized and employed to construct a vertical heterojunction photodetector. At a bias voltage of −5 V, the photodetector exhibits a responsivity of 1052 A/W, outperforming previous graphene-based heterojunction photodetectors by several orders of magnitude. The achieved detectivity of 3.13 × 10 13 Jones and response time of 310 μs are also among the best values for graphene-based heterojunction photodetectors reported until date. Furthermore, even under zero bias, the photodetector demonstrates a high responsivity and detectivity of 1.04 A/W and 2.45 × 10 12 Jones, respectively. The work shows a great potential of graphene nanoribbon-based photodetection technology.

High Performance Self-Powered Photodetectors Based on Graphene Nanoribbons/Al2O3/InGaZnO Heterojunctions

“…The peak transmission of infrared and visible light at 20 nm thickness is comparable to the transparency of commercial films like indium-tin-oxide, polyethylene terephthalate, and polycarbonate. Furthermore, the pronounced photoresponse in GNR/Al2O3/IGZO photo- detectors primarily stems from light absorption in the GNR layer [43]. GNR films that are too thin compromise their light absorption capability, thus reducing the device's responsivity.…”

“…The reduced reverse current through the Al2O3 barrier lowers hole density in the GNR valence band. In addition, the GNR with an open bandgap plays a key role in photon absorption, enhancing photodetection performance [43].…”

Dual-benefit strategy for developing an efficient photodetector with prompt response to UV-near IR radiations: in situ synthesis and crystallization through a simple one-step annealing

“…, low absorption due to the atomic thickness, short carrier lifetime, and lack of sufficient built-in field. 1,3,4,33–35 Fabricating organic/2D hybrids as the functional parts of photodetectors may combine their favorable properties and alleviate the shortcomings of any of the single materials. 4,36–38 The G sheets transferred on the octadecyltrichlorosilane-modified SiO 2 /Si substrate have a smoother topography and uniform doping.…”

Light-Triggered Anti-ambipolar Transistor Based on an In-Plane Lateral Homojunction

“…4−6 Furthermore, when irradiation is introduced, it is almost impossible to ascertain the principles. 3,15 Indeed, the principles guiding conventional AATs are controversial, while the physical principles of light-triggered anti-ambipolar transistors are even more intricate. 3,4 Therefore, there is a need to develop structurally optimized AATs without van der Waals (vdW) heterojunctions to simplify fabrication and address theoretical research challenges.…”

“…In existing methods, AATs are constructed based on heterojunctions, requiring sophisticated transfer techniques. − Unfortunately, precise transfers entail a certain risk of failure, increased operational complexity and time costs. − Moreover, the band structure of two-dimensional (2D) materials changes significantly with layer count, requiring precise identification techniques. , In principle, the energy bands of both the p/n-type semiconductors and the intermediate heterojunction change simultaneously under gate modulation. − Furthermore, when irradiation is introduced, it is almost impossible to ascertain the principles. , Indeed, the principles guiding conventional AATs are controversial, while the physical principles of light-triggered anti-ambipolar transistors are even more intricate. , Therefore, there is a need to develop structurally optimized AATs without van der Waals (vdW) heterojunctions to simplify fabrication and address theoretical research challenges …”