Direct Visualization of Electric Field induced Structural Dynamics in Monolayer Transition Metal Dichalcogenides
arXiv:1910.02879 · doi:10.1021/acsnano.9b06581
Abstract
Layered transition metal dichalcogenides (TMDs) offer many attractive features for next-generation low-dimensional device geometries. Due to the practical and fabrication challenges related to in situ methods, the atomistic dynamics that give rise to realizable macroscopic device properties are often unclear. In this study, in situ transmission electron microscopy techniques are utilized in order to understand the structural dynamics at play, especially at interfaces and defects, in the prototypical film of monolayer MoS2 under electrical bias. Through our sample fabrication process, we clearly identify the presence of mass transport in the presence of a lateral electric field. In particular, we observe that the voids present at grain boundaries combine to induce structural deformation. The electric field mediates a net vacancy flux from the grain boundary interior to the exposed surface edge sites that leaves molybdenum clusters in its wake. Following the initial biasing cycles, however, the mass flow is largely diminished, and the resultant structure remains stable over repeated biasing. We believe insights from this work can help explain observations of non-uniform heating and preferential oxidation at grain boundary sites in these materials.
arXiv comment4 figures, ACS Nano
References in corpus (14)
- Atomically thin MoS2: A new direct-gap semiconductor
- Grains and grain boundaries in highly crystalline monolayer molybdenum disulfide
- Strong Photoluminescence Enhancement of MoS2 through Defect Engineering and Oxygen Bonding
- Multi-Terminal Memtransistors from Polycrystalline Monolayer MoS2
- Channel Length Scaling of MoS2 MOSFETs
- Gate-tunable Memristive Phenonmena Mediated by Grain Boundaries in Single Layer MoS2
- Thickness-Dependent Interfacial Coulomb Scattering in Atomically Thin Field-Effect Transistors
- Photoluminescence of freestanding single- and few-layer MoS2
- Control of Radiation Damage in MoS2 by Graphene Encapsulation
- Energy Dissipation in Monolayer MoS Electronics
- Point Defects and Grain Boundaries in Rotationally Commensurate MoS2 on Epitaxial Graphene
- Grain boundary-mediated nanopores in molybdenum disulfide grown by chemical vapor deposition
- Measurement of lateral and interfacial thermal conductivity of single- and bi-layer MoS2 and MoSe2 using refined optothermal Raman technique
- Properties of Individual Dopant Atoms in Single-Layer MoS2: Atomic Structure, Migration, and Enhanced Reactivity