Highly responsive near-infrared photodetector with low dark current using graphene/germanium Schottky junction with Al 2 O 3 interfacial layer

Nanophotonics

article

Cihyun Kim¹  Tae Jin Yoo¹  Kyoung Eun Chang²  Min Gyu Kwon²  Hyeon Jun Hwang¹  Byoung Hun Lee¹ 

[1] Department of Electrical Engineering, Pohang University of Science and Technology;School of Materials Science and Engineering, Gwangju Institute of Science and Technology

关键词: graphene;    graphene/germanium heterostructure;    interfacial oxide layer;    photodetector;    Schottky junction;   

DOI  :  10.1515/nanoph-2021-0002

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

The performance of a graphene/Ge Schottky junction near-infrared photodetector is significantly enhanced by inserting a thin Al 2 O 3 interfacial layer between graphene and Ge. Dark current is reduced by two orders of magnitudes, and the specific detectivity is improved to 1.9 × 10 10  cm ⋅ Hz 1/2 W −1 . The responsivity is improved to 1.2 AW −1 with an interfacial layer from 0.5 AW −1 of the reference devices. The normalized photo-to-dark current ratio is improved to 4.3 × 10 7  W −1 at a wavelength of 1550 nm, which is 10–100 times higher than those of other Ge photodetectors.

【 授权许可】

CC BY