Making one‐dimensional electrical contacts to molybdenum disulfide‐based heterostructures through plasma etching
Abstract
A “passivation first, metallization second” technique is developed for fabricating edge contacts to a multi‐layer MoS2 sample encapsulated under an Al2O3 thin film. The in‐time sealing of the newly exfoliated MoS2 under a dielectric ensures a complete isolation from the environment. CF4 plasma is used to open trenches in the passivation layer and to expose the atoms at the edges of MoS2. Edge contacts are next made to h‐BN/MoS2/h‐BN 3‐level heterostructures, earlier assembled through a solvent‐free 2D material transfer procedure. Both types of MoS2‐based heterostructures are further fabricated into back‐gated FETs and show n‐type doping behavior. In particular, trends of field‐effect mobility with respect to a varying drain voltage are analyzed based on the ID–VDS data measured from each device. The result verifies the effect of Schottky barrier on channel conduction, which is, only at the presence of a highly transparent contact interface, the field‐effect mobility can manifest the intrinsic material property by staying constant against the changes in drain voltage. The wide applicability of the processing sequence makes edge contacts an appealing option to future nanoelectronics on 2D heterostructures.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 25, 2016
- Source ID
- 10.1002/pssa.201532799
Entities
People
- Cengiz S Ozkan
- Mihrimah Ozkan
- Robert Ionescu
- Roger Lake
- Shanshan Su
- Yu Chai
Organizations
- Defense Advanced Research Projects Agency
- University of California, Riverside