Atomic-Scale Mechanisms of MoS 2 Oxidation for Kinetic Control of MoS 2 /MoO 3 Interfaces

作者：Kate Reidy, Wouter Mortelmans, Seong Soon Jo, Aubrey Penn, Alexandre C. Foucher, Zhenjing Liu, Tao Cai, Baoming Wang, Frances M. Ross, R. Jaramillo · 发表于：Nano Letters · 年份：2023 · DOI：10.1021/acs.nanolett.3c00303 · 被引用次数：41 · 研究领域：2D Materials and Applications、Perovskite Materials and Applications、Advanced Memory and Neural Computing

Oxidation of transition metal dichalcogenides (TMDs) occurs readily under a variety of conditions. Therefore, understanding the oxidation processes is necessary for successful TMD handling and device fabrication. Here, we investigate atomic-scale oxidation mechanisms of the most widely studied TMD, MoS 2 . We find that thermal oxidation results in α-phase crystalline MoO 3 with sharp interfaces, voids, and crystallographic alignment with the underlying MoS 2 . Experiments with remote substrates prove that thermal oxidation proceeds via vapor-phase mass transport and redeposition, a challenge to forming thin, conformal films. Oxygen plasma accelerates the kinetics of oxidation relative to the kinetics of mass transport, forming smooth and conformal oxides. The resulting amorphous MoO 3 can be grown with subnanometer to several-nanometer thickness, and we calibrate the oxidation rate for different instruments and process parameters. Our results provide quantitative guidance for managing both the atomic scale structure and thin-film morphology of oxides in the design and processing of TMD devices.