APS March Meeting 2016
Volume 61, Number 2
Monday–Friday, March 14–18, 2016;
Baltimore, Maryland
Session E2: Computational Methods for Improved Transparent Conducting Oxides
8:00 AM–11:00 AM,
Tuesday, March 15, 2016
Room: Ballroom II
Sponsoring
Units:
DCOMP DCMP
Chair: Giulia Galli, Univ of Chicago
Abstract ID: BAPS.2016.MAR.E2.1
Abstract: E2.00001 : Structure and Properties of Amorphous Transparent Conducting Oxides*
8:00 AM–8:36 AM
Preview Abstract
Abstract
Author:
Julia Medvedeva
(Missouri University of Science and Technology)
Driven by technological appeal, the research area of amorphous oxide
semiconductors has grown tremendously since the first demonstration of the
unique properties of amorphous indium oxide more than a decade ago. Today,
amorphous oxides, such as a-ITO, a-IZO, a-IGZO, or a-ZITO, exhibit the
optical, electrical, thermal, and mechanical properties that are comparable
or even superior to those possessed by their crystalline counterparts,
pushing the latter out of the market. Large-area uniformity, low-cost
low-temperature deposition, high carrier mobility, optical transparency, and
mechanical flexibility make these materials appealing for next-generation
thin-film electronics.
Yet, the structural variations associated with crystalline-to-amorphous
transition as well as their role in carrier generation and transport
properties of these oxides are far from being understood. Although amorphous
oxides lack grain boundaries, factors like (i) size and distribution of
nanocrystalline inclusions; (ii) spatial distribution and clustering of
incorporated cations in multicomponent oxides; (iii) formation of trap
defects; and (iv) piezoelectric effects associated with internal strains,
will contribute to electron scattering.
In this work, ab-initio molecular dynamics (MD) and accurate
density-functional approaches are employed to understand how the properties
of amorphous ternary and quaternary oxides depend on quench rates, cation
compositions, and oxygen stoichiometries. The MD results, combined with
thorough experimental characterization, reveal that interplay between the
local and long-range structural preferences of the constituent oxides gives
rise to a complex composition-dependent structural behavior in the amorphous
oxides. The proposed network models of metal-oxygen polyhedra help explain
the observed intriguing electrical and optical properties in In-based oxides
and suggest ways to broaden the phase space of amorphous oxide
semiconductors with tunable properties.
*The work is supported by NSF-MRSEC program
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2016.MAR.E2.1