Conformal Growth of Nano‐Patterned Monolayer MoS 2 with Periodic Strain via Patterned Substrate Engineering for High‐performance Photodetectors

作者：Pengcheng Jian, Maohua Chen, Dongyan Li, Yongming Zhao, Weijie Liu, Yuang Luo, Xiantai Tian, Meng Peng, Xing Zhou, Jiangnan Dai, Feng Wu, Changqing Chen · 发表于：Laser & Photonics Review · 年份：2024 · DOI：10.1002/lpor.202401012 · 被引用次数：6 · 研究领域：2D Materials and Applications、MXene and MAX Phase Materials、Perovskite Materials and Applications

Abstract The extraordinary mechanical compliance of 2D molybdenum disulfide (MoS 2 ) makes it an ideal candidate for strain modulation of various electrical and optical properties. However, developing facile methods for accurate and stable engineering of strain still remains a major challenge. Here, a novel and effective method is demonstrated for introducing periodic strain into monolayer MoS 2 by direct growth on nano‐patterned sapphire substrates (NPSS). A mixed aqueous solution of Na 2 MoO 4 and NaOH is spin‐coated on the NPSS and sulfurated in one step by chemical vapor deposition (CVD). Highly oriented monolayer MoS 2 single‐crystal nanosheets with high quality and few sulfur vacancies are achieved conformally on the NPSS via a liquid‐mediated growth mode. Notably, the periodically distributed blue shift of the PL emission peak demonstrated periodic compressive strain is introduced into the nano‐patterned MoS 2 via the thermal expansion difference between MoS 2 and substrates. Furthermore, photodetectors fabricated using the nano‐patterned monolayer MoS 2 exhibit a high photo‐to‐dark current ratio (PDCR) over 10 6 , an excellent detectivity of 5.4 × 10 13 Jones, and a fast photoresponse of 7.7 ms, owing to the strain‐induced back‐to‐back built‐in electric field, enhanced light absorption by light‐scattering effect and fewer S vacancy defects. The scanning imaging demonstration based on the single‐pixel nano‐patterned MoS 2 photodetector further confirms its great potent...