Quasi One-Dimensional Metal-Semiconductor Heterostructures

Quasi One-Dimensional Metal-Semiconductor Heterostructures

Článek WoS

The band offsets occurring at the abrupt heterointerfaces of suitable material combinations offer a powerful design tool for high performance or even new kinds of devices. Because of a large variety of applications for metal- semiconductor heterostructures and the promise of low-dimensional systems to present exceptional device characteristics, nanowire heterostructures gained particular interest over the past decade. However, compared to those achieved by mature two-dimensional processing techniques, quasi one-dimensional (1D) heterostructures often suffer from low interface and crystalline quality. For the GaAs-Au system, we demonstrate exemplarily a new approach to generate epitaxial and single crystalline metal-semiconductor nanowire heterostructures with atomically sharp interfaces using standard semiconductor processing techniques. Spatially resolved Raman measurements exclude any significant strain at the lattice mismatched metal-semiconductor heterojunction. On the basis of experimental results and simulation work, a novel self-assembled mechanism is demonstrated which yields one-step reconfiguration of a semiconductor-metal core-shell nanowire to a quasi 1D axially stacked heterostructure via flash lamp annealing. Transmission electron microscopy imaging and electrical characterization confirm the high interface quality resulting in the lowest Schottky barrier for the GaAs-Au system reported to date. Without limiting the generality, this novel approach will open up new opportunities in the syntheses of other metal-semiconductor nanowire heterostructures and thus facilitate the research of high-quality interfaces in metal-semiconductor nanocontacts.

The band offsets occurring at the abrupt heterointerfaces of suitable material combinations offer a powerful design tool for high performance or even new kinds of devices. Because of a large variety of applications for metal- semiconductor heterostructures and the promise of low-dimensional systems to present exceptional device characteristics, nanowire heterostructures gained particular interest over the past decade. However, compared to those achieved by mature two-dimensional processing techniques, quasi one-dimensional (1D) heterostructures often suffer from low interface and crystalline quality. For the GaAs-Au system, we demonstrate exemplarily a new approach to generate epitaxial and single crystalline metal-semiconductor nanowire heterostructures with atomically sharp interfaces using standard semiconductor processing techniques. Spatially resolved Raman measurements exclude any significant strain at the lattice mismatched metal-semiconductor heterojunction. On the basis of experimental results and simulation work, a novel self-assembled mechanism is demonstrated which yields one-step reconfiguration of a semiconductor-metal core-shell nanowire to a quasi 1D axially stacked heterostructure via flash lamp annealing. Transmission electron microscopy imaging and electrical characterization confirm the high interface quality resulting in the lowest Schottky barrier for the GaAs-Au system reported to date. Without limiting the generality, this novel approach will open up new opportunities in the syntheses of other metal-semiconductor nanowire heterostructures and thus facilitate the research of high-quality interfaces in metal-semiconductor nanocontacts.

Nanowire; GaAs; gold; metal-semiconductor heterostructure; quasi 1D contacts

Nanowire; GaAs; gold; metal-semiconductor heterostructure; quasi 1D contacts

Benter, S.; Dubrovskii, VG.; Bartmann, M.; Campo, A.; Zardo, I. ; Sistani, M.; Stoger-Pollach, M.; Lancaster, S. ; Detz, H.; Lugstein, A.

2020

01.06.2019

1530-6992

NANO LETTERS

19

6

Spojené státy americké

3892

3897

6

https://pubs.acs.org/doi/10.1021/acs.nanolett.9b01076