Prospects for creating complex oxide quantum electronic heterostructures via solid phase epitaxy: PrAlO3/SrTiO3 model system

ORAL

Abstract

Various oxide interfaces with composition RAlO3/SrTiO3 (R = La, Pr, Nd) can produce a two-dimensional electron gas (2DEG). Crystallization from amorphous precursors, termed solid phase epitaxy (SPE), is an approach for synthesizing these interfaces that complements vapor-phase epitaxy techniques. Atomic layer deposition (ALD) is a promising route for forming the amorphous films because it allows oxide interfaces to be created in non-planar geometries. SPE can be used with patterned substrates to grow epitaxial thin films in complex geometries, which may enable the creation of 2DEG beyond planar geometries.
The creation of PrAlO3 thin films via SPE has required developing new ALD procedures, understanding crystallization kinetics, and probing the microstructure and interface structures of the crystallized thin films. Nearly stoichiometric amorphous PrAlO3 thin films were grown via ALD at 300 °C using tris(isopropylcyclopentadienyl)praseodymium, AlMe3, and water with a growth rate of 2.0 Å/cycle on TiO2-terminated STO (001) substrates. The as-deposited amorphous PrAlO3 crystallized via SPE to form an epitaxial layer on STO upon annealing at 800 °C for 3h. Our work provides new opportunities to form polar/nonpolar oxide interfaces, and the accompanying 2DEG in novel geometries.

Presenters

  • Yajin Chen

    Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA

Authors

  • Yajin Chen

    Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA

  • Wathsala Waduge

    Department of Chemistry, Wayne State University, Detroit, MI 48202, USA

  • Peng Zuo

    Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA

  • Thomas F. Kuech

    Department of of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA

  • Sue E. Babcock

    Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA

  • Chuck H. Winter

    Department of Chemistry, Wayne State University, Detroit, MI 48202, USA

  • Paul G Evans

    Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA, Department of Materials Science & Engineering, University of Wisconsin - Madison, Madison, Wisconsin 53706, USA