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arXiv · 1705.03051

Intra-Domain Periodic Defects in Monolayer MoS$_2$

Anupam Roy·Rudresh Ghosh·Amritesh Rai·Atresh Sanne·Kyounghwan Kim·Hema C. P. Movva·Rik Dey·Tanmoy Pramanik·Sayema Chowdhury·Emanuel Tutuc·Sanjay K. Banerjee
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Abstract

We present an ultra-high vacuum scanning tunneling microscopy (STM) study of structural defects in molybdenum disulfide thin films grown on silicon substrates by chemical vapor deposition. A distinctive type of grain boundary periodically arranged inside an isolated triangular domain, along with other inter-domain grain boundaries of various types, is observed. These periodic defects, about 50 nm apart and a few nanometers in width, remain hidden in optical or low-resolution microscopy studies. We report a complex growth mechanism that produces 2D nucleation and spiral growth features that can explain the topography in our films.

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Anupam Roy, Rudresh Ghosh, Amritesh Rai, Atresh Sanne, Kyounghwan Kim, Hema C. P. Movva, Rik Dey, Tanmoy Pramanik, Sayema Chowdhury, Emanuel Tutuc, Sanjay K. Banerjee. 2017-05-08. Intra-Domain Periodic Defects in Monolayer MoS$_2$. https://doi.org/10.1063/1.4983789

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