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Title: Final Report on "Microscopy of Electrostatic Field Effect in Novel Quantum Materials"

Abstract

In this DOE Early Career project “Microscopy of Electrostatic Field Effect in Novel Quantum Materials”, the PI’s group explored the nanoscale electronic properties when charge carriers are electrostatically modulated in functional materials. Using a microwave impedance microscope (MIM), the team probed the spatial evolution of local conductivity in various field-effect transistors (FETs) ranging from traditional metal-oxide-semiconductor FETs, sketched oxide-interface FETs, to ferroelectric FETs and electric double-layer transistors (EDLTs). Specifically, the work has led to a deep understanding on the electrical inhomogeneity and conductive edge channels in atomically thin transition metal dichalcogenides and their heterostructures, which is of fundamental importance for their applications in electronics and photonics. The unique sub-surface imaging capability also enables the first-time report of ferroelectric field effect on Ge substrates due to the polarization switching of an epitaxial BaTiO3 layer, as well as the visualization of sketched nanostructures in the LaAlO3/SrTiO3 interface. Using a cryogenic MIM, the local channel conductance in ion-gel-gated oxide EDLTs has been successfully imaged, resolving a major challenge in the EDLT research to study electronic fluctuations in the devices. Finally, a new tuning-fork-based MIM has been developed to perform quantitative conductivity imaging on back-gated FETs. The research supported by this DOE grant ismore » significant for understanding the nanoscale uniformity in technologically important materials towards energy applications.« less

Authors:
ORCiD logo [1]
  1. Univ. of Texas, Austin, TX (United States)
Publication Date:
Research Org.:
Univ. of Texas, Austin, TX (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1505896
Report Number(s):
DOE-UT Austin-10308
DOE Contract Number:  
SC0010308
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; Electrostatic field effect; microwave impedance microscope; nanoscale inhomogeneity; 2D materials; heterostructures

Citation Formats

Lai, Keji. Final Report on "Microscopy of Electrostatic Field Effect in Novel Quantum Materials". United States: N. p., 2019. Web. doi:10.2172/1505896.
Lai, Keji. Final Report on "Microscopy of Electrostatic Field Effect in Novel Quantum Materials". United States. doi:10.2172/1505896.
Lai, Keji. Sat . "Final Report on "Microscopy of Electrostatic Field Effect in Novel Quantum Materials"". United States. doi:10.2172/1505896. https://www.osti.gov/servlets/purl/1505896.
@article{osti_1505896,
title = {Final Report on "Microscopy of Electrostatic Field Effect in Novel Quantum Materials"},
author = {Lai, Keji},
abstractNote = {In this DOE Early Career project “Microscopy of Electrostatic Field Effect in Novel Quantum Materials”, the PI’s group explored the nanoscale electronic properties when charge carriers are electrostatically modulated in functional materials. Using a microwave impedance microscope (MIM), the team probed the spatial evolution of local conductivity in various field-effect transistors (FETs) ranging from traditional metal-oxide-semiconductor FETs, sketched oxide-interface FETs, to ferroelectric FETs and electric double-layer transistors (EDLTs). Specifically, the work has led to a deep understanding on the electrical inhomogeneity and conductive edge channels in atomically thin transition metal dichalcogenides and their heterostructures, which is of fundamental importance for their applications in electronics and photonics. The unique sub-surface imaging capability also enables the first-time report of ferroelectric field effect on Ge substrates due to the polarization switching of an epitaxial BaTiO3 layer, as well as the visualization of sketched nanostructures in the LaAlO3/SrTiO3 interface. Using a cryogenic MIM, the local channel conductance in ion-gel-gated oxide EDLTs has been successfully imaged, resolving a major challenge in the EDLT research to study electronic fluctuations in the devices. Finally, a new tuning-fork-based MIM has been developed to perform quantitative conductivity imaging on back-gated FETs. The research supported by this DOE grant is significant for understanding the nanoscale uniformity in technologically important materials towards energy applications.},
doi = {10.2172/1505896},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2019},
month = {4}
}

Works referencing / citing this record:

Quantitative measurements of nanoscale permittivity and conductivity using tuning-fork-based microwave impedance microscopy
journal, April 2018

  • Wu, Xiaoyu; Hao, Zhenqi; Wu, Di
  • Review of Scientific Instruments, Vol. 89, Issue 4
  • DOI: 10.1063/1.5022997

Uncovering edge states and electrical inhomogeneity in MoS 2 field-effect transistors
journal, July 2016

  • Wu, Di; Li, Xiao; Luan, Lan
  • Proceedings of the National Academy of Sciences, Vol. 113, Issue 31
  • DOI: 10.1073/pnas.1605982113

Direct imaging of sketched conductive nanostructures at the LaAlO 3 /SrTiO 3 interface
journal, December 2017

  • Jiang, Zhanzhi; Wu, Xiaoyu; Lee, Hyungwoo
  • Applied Physics Letters, Vol. 111, Issue 23
  • DOI: 10.1063/1.5005917

Direct Imaging of Nanoscale Conductance Evolution in Ion-Gel-Gated Oxide Transistors
journal, June 2015


Visualization of Local Conductance in MoS 2 /WSe 2 Heterostructure Transistors
journal, February 2019


Carrier density modulation in a germanium heterostructure by ferroelectric switching
journal, January 2015

  • Ponath, Patrick; Fredrickson, Kurt; Posadas, Agham B.
  • Nature Communications, Vol. 6, Issue 1
  • DOI: 10.1038/ncomms7067