Kim Cihyun, Yoo Tae Jin, Kwon Min Gyu, Chang Kyoung Eun, Hwang Hyeon Jun, Lee Byoung Hun
Department of Electrical Engineering, Pohang University of Science and Technology, 77, Cheongam-ro, Nam-gu, Pohang-si, Gyeongsangbuk-do, 37673, Republic of Korea.
School of Materials Science and Engineering, Gwangju Institute of Science and Technology, 123, Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea.
Nanophotonics. 2022 Jan 7;11(5):1041-1049. doi: 10.1515/nanoph-2021-0738. eCollection 2022 Feb.
The structure of a gate-controlled graphene/germanium hybrid photodetector was optimized by splitting the active region to achieve highly sensitive infrared detection capability. The strengthened internal electric field in the split active junctions enabled efficient collection of photocarriers, resulting in a responsivity of 2.02 A W and a specific detectivity of 5.28 × 10 Jones with reduced dark current and improved external quantum efficiency; these results are more than doubled compared with the responsivity of 0.85 A W and detectivity of 1.69 × 10 Jones for a single active junction device. The responsivity of the optimized structure is 1.7, 2.7, and 39 times higher than that of previously reported graphene/Ge with AlO interfacial layer, gate-controlled graphene/Ge, and simple graphene/Ge heterostructure photodetectors, respectively.
通过分割有源区优化了栅控石墨烯/锗混合光电探测器的结构，以实现高灵敏度红外探测能力。分割后的有源结中增强的内部电场能够有效地收集光载流子，从而产生了2.02 A/W的响应度和5.28×10 Jones的比探测率，同时暗电流降低，外部量子效率提高；与单个有源结器件0.85 A/W的响应度和1.69×10 Jones的探测率相比，这些结果提高了一倍多。优化结构的响应度分别比先前报道的具有AlO界面层的石墨烯/锗、栅控石墨烯/锗和简单石墨烯/锗异质结构光电探测器高1.7倍、2.7倍和39倍。
