Multilayered PdTe2/thin Si heterostructures as self-powered flexible photodetectors with heart rate monitoring ability

• Published in: Journal of semiconductors 2023-11, Vol.44 (11), p.46-56
• Main Authors: Dong, Chengyun, An, Xiang, Wu, Zhicheng, Zhu, Zhiguo, Xie, Chao, Huang, Jian-An, Luo, Linbao
• Format: Article
• Language: English
• Subjects: 2D layered material; flexible; health monitoring; heterostructure; photodetector
• ISSN: 1674-4926
• DOI: 10.1088/1674-4926/44/11/112001

Two-dimensional layered material/semiconductor heterostructures have emerged as a category of fascinating architec-tures for developing highly efficient and low-cost photodetection devices. Herein, we present the construction of a highly effi-cient flexible light detector operating in the visible-near infrared wavelength regime by integrating a PdTe2 multilayer on a thin Si film. A representative device achieves a good photoresponse performance at zero bias including a sizeable current on/off ratio exceeding 105, a decent responsivity of ～343 mA/W, a respectable specific detectivity of ～2.56 × 1012 Jones, and a rapid response time of 4.5/379 μs, under 730 nm light irradiation. The detector also displays an outstanding long-term air stabil-ity and operational durability. In addition, thanks to the excellent flexibility, the device can retain its prominent photodetec-tion performance at various bending radii of curvature and upon hundreds of bending tests. Furthermore, the large responsiv-ity and rapid response speed endow the photodetector with the ability to accurately probe heart rate, suggesting a possible application in the area of flexible and wearable health monitoring.