Strong Schottky barrier reduction at Au-catalyst/GaAs-nanowire interfaces by electric dipole formation and Fermi-level unpinning.
Nanoscale contacts between metals and semiconductors are critical for further downscaling of electronic and optoelectronic devices. However, realizing nanocontacts poses significant challenges since conventional approaches to achieve ohmic contacts through Schottky barrier suppression are often inadequate. Here we report the realization and characterization of low n-type Schottky barriers (~0.35 eV) formed at epitaxial contacts between Au-In alloy catalytic particles and GaAs-nanowires. In comparison to previous studies, our detailed characterization, employing selective electrical contacts defined by high-precision electron beam lithography, reveals the barrier to occur directly and solely at the abrupt interface between the catalyst and nanowire. We attribute this lowest-to-date-reported Schottky barrier to a reduced density of pinning states (~10(17) m(-2)) and the formation of an electric dipole layer at the epitaxial contacts. The insight into the physical mechanisms behind the observed low-energy Schottky barrier may guide future efforts to engineer abrupt nanoscale electrical contacts with tailored electrical properties.
Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden.
Dmitry B
DB
Suyatin
1] Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden [2] Department of Mathematics, Physics and Electrical Engineering, Halmstad University, Box 823, SE-301 18 Halmstad, Sweden.
Vishal
V
Jain
Voronezh State Technical University, Moskovskii pr. 14, RU-394026 Voronezh, Russia.
Valery A
VA
Nebol'sin
Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden.
Johanna
J
Trägårdh
Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden.
Maria E
ME
Messing
Division of Polymer and Materials Chemistry, Lund University, Box 124, SE-221 00 Lund, Sweden.
Jakob B
JB
Wagner
Division of Synchrotron Radiation Research and The Nanometer Structure Consortium, Lund University, Box 118, SE-221 00 Lund, Sweden.
Olof
O
Persson
Division of Synchrotron Radiation Research and The Nanometer Structure Consortium, Lund University, Box 118, SE-221 00 Lund, Sweden.
Rainer
R
Timm
Division of Synchrotron Radiation Research and The Nanometer Structure Consortium, Lund University, Box 118, SE-221 00 Lund, Sweden.
Anders
A
Mikkelsen
Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden.
Ivan
I
Maximov
Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden.
Lars
L
Samuelson
1] Division of Solid State Physics and The Nanometer Structure Consortium (nmC@LU), Lund University, Box 118, SE-221 00 Lund, Sweden [2] Department of Mathematics, Physics and Electrical Engineering, Halmstad University, Box 823, SE-301 18 Halmstad, Sweden.
Håkan
H
Pettersson