Reversible tuning of two-dimensional electron gases in oxide heterostructures by chemical surface modification

Abstract

Reversible control over the electrical properties of the two-dimensional electron gas (2DEG) in oxide heterostructures is a key capability enabling practical applications. Herein, we report an efficient method to reversibly tune the charge carrier density of the 2DEG by surface modification. We demonstrate both increasing and decreasing the carrier density of the LaAlO3/SrTiO3 2DEG interface via application of functional phosphonic acids with molecular dipoles pointing either toward or away from the interface, respectively. In addition, in the case of the enhanced 2DEG, we recovered the initial conduction properties by exposing the samples to a basic solution. The tuning processes were highly reversible over repetitive cycles. These results reveal that the surface modification is an efficient way to tune the carrier density of 2DEG in oxide heterostructures. This simple chemical approach offers a vast range of fabrication possibilities in versatile electronic device applications.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 07, 2016
Source ID
10.1063/1.4967472

Entities

People

  • C. B. Eom
  • Hanwool Lee
  • Julian Irwin
  • M. K. Mahanthappa
  • M. S. Rzchowski
  • N. Campbell
  • S. Lindemann
  • Sangwoo Ryu
  • Wen‐Hsin Chang

Organizations

  • Air Force Office of Scientific Research
  • University of Wisconsin–Madison

Tags

Fields of Study

  • Materials science

Readers

  • Analytical Chemistry
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene