Kelvin Probe Force Microscopy Study of LaAlO3/SrTiO3 Heterointerfaces
Journal article, 2010

Surface potential distributions in ultra-thin (0.8-3.9 nm) LaAlO3 layers deposited on SrTiO3 substrates are studied. It is found that the potential distribution evolves from island-like to a homogeneous one with increasing LaAlO3 thickness. It is suggested that the observed islands are caused by a locally enhanced concentration of mobile charge carriers at the interface that is, in turn, related to non-stoichiometry of the layers with thickness bellow 4 unit cells. Transition to a homogeneous potential distribution with increasing LAO thickness (≥4 unit cells) corresponds to the formation of a quasi-2-dimensional electron gas. The results agree with a percolation model explaining the insulator-to-metal transition that occurs at the LaAlO3/SrTiO3 heterointerface.

LaAlO 3/SrTiO 3 Heterointerface

Kelvin Probe Force Microscopy

Author

Vladimir Popok

Technische Universiteit Eindhoven

University of Gothenburg

Alexei Kalaboukhov

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Robert Gunnarsson

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

S. Lemenshko

Chalmers, Microtechnology and Nanoscience (MC2)

Tord Claeson

Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics

Dag Winkler

Chalmers, Microtechnology and Nanoscience (MC2)

Journal of Advanced Microscopy Research

2156-7573 (ISSN) 2156-7581 (eISSN)

Vol. 5 1 26-30

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Materials Science

Subject Categories

Other Engineering and Technologies not elsewhere specified

Condensed Matter Physics

DOI

10.1166/jamr.2010.1020

More information

Latest update

7/22/2019