Periodic Strain in Patterned CVD Grown MoS₂

Transition metal dichalcogenides (TMD) have emerged as promising materials for novel optical and electronic devices on the nano-scale due to the myriad of unique and tunable properties they display at the single layer. Deformations of TMD materials, such as folds and valleys, result in localized variations in the electronic structure and modification of its optoelectronic properties. We will present results of a process for developing crystalline growth of high-quality MoS₂ with periodic strain resulting from naturally occurring folds. The material is formed from a pre-deposited transition metal pattern which acts as both a seed material and forms as-grown complimentary metal-oxide electrical contacts. We observe lateral material growth on the order of 50 microns with two naturally occurring patterns, one with periodic folds typically at a 2 micron separation occurring through most of the material, the other with folds at a 1 micron separation occurring at the edge of the grown material extending up to 10 microns. Photoluminescence mapping is indicative of MoS₂ and shows increased intensity at separations which correspond to the local periodic growth. Further understanding of this growth process could lead to scalable deterministic induced strain devices.