High responsivity and stability of MSM structured MoS 2 photodetectors by remote hydrogen plasma treatment and alternating growth of Al 2 O 3 /HfO 2 passivation layers

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-07, Vol.12 (29), p.18487-18497
• Main Authors: Li, Yulin, Tian, Yajun, Bao, Lingjie, Cheng, Haoran, Cheng, Qijin
• Format: Article
• Language: English
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/D4TA01523A

Molybdenum disulfide (MoS 2 ) is a representative material of transition metal dichalcogenides with a wide range of potential practical applications. However, the low responsivity and relatively short lifespan of MoS 2 photodetectors restrict their further development. To enhance the performance of MoS 2 photodetectors, we propose a strategy involving defect introduction and surface passivation. Sulphur vacancy defects are introduced in MoS 2 through remote hydrogen plasma treatment and surface passivation of MoS 2 is achieved by alternating growth of Al 2 O 3 /HfO 2 passivation layers. The obtained MoS 2 photodetector features a high responsivity of 567 A W −1 , a specific detectivity of 1.12 × 10 10 jones, and a response time of 10.51/15.78 s at a bias of −5 V. Moreover, the obtained MoS 2 photodetector maintains excellent stability. It is demonstrated that, after 2 months of placement in an atmospheric environment, the responsivity and the specific detectivity are maintained at approximately 95% of the fresh device, while the response time slightly increases. Finally, the underlying physical mechanism based on the energy band diagram has been proposed to interpret the obtained experimental results. The simple and efficient method proposed in this study for improving the performance of the MoS 2 photodetector can open up new avenues for research in MoS 2 -based photoelectric devices.