Zinc Oxide Nanostructure Synthesis on Si(100) by Vapor Phase Transport and the Effect of Antimony Doping on Photoelectri
- PDF / 1,494,490 Bytes
- 9 Pages / 432 x 648 pts Page_size
- 61 Downloads / 175 Views
MRS Advances © 2020 Materials Research Society DOI: 10.1557/adv.2020.150
Zinc Oxide Nanostructure Synthesis on Si(100) by Vapor Phase Transport and the Effect of Antimony Doping on Photoelectric Properties, Morphology, and Structure Tarek Trad 1*, Parker Blount 1, Zuleyma Romero 1, and David Thompson1 1
Department of Chemistry, Sam Houston State University, 1003 Bowers Blvd., Huntsville, TX 77340, U.S.A.
ABSTRACT Zinc Oxide (ZnO) has been shown to exhibit semiconducting and piezoelectric dual properties. This has led to a large commercial demand on ZnO for optoelectronics that operate at the blue-ultraviolet regions. Consequently, varying techniques have been devised to create different nanostructures of ZnO. Here, the single step synthesis of ZnO nanostructures was performed on Si(100) substrates with a thin ZnO seed-layer. A modified chemical vapor deposition (CVD) method was developed to accomplish the structure formation. Sb doping of the structures in the gas phase was performed to study its effects on structure and optoelectronic properties. Different structures were realized including nanofilaments, nanoparticles, microflowers, nanorods, nanotubes, and nanocolumns. Only nanorods/columns, and nanotubes are shown in this work. Morphology was examined using scanning electron microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDS) and X-ray powder diffraction (XRD) were used for structural studies. Optoelectronic properties were explored using room-temperature photoluminescence (PL) spectroscopy. PL data show the relative decrease in the number of defects and increase in crystal quality upon increasing reaction time. Significant structural effects were also observed upon doping. Some structural defects might be attributed to the diffusion of Sb ions into the lattices of ZnO, replacement of Zn by Sb, and ionic radii difference. These stacking faults are most likely the reason behind the dominance and broadening of DLE peak.
INTRODUCTION The interest in one-dimensional ZnO nanostructure materials is mainly due to its wide bandgap (3.4 eV at 2 K) and large free exciton binding energy of ~ 60 meV at room temperature. The latter which holds superior advantage over major competitor,
Downloaded from https://www.cambridge.org/core. University of Texas Libraries, on 29 May 2020 at 23:40:45, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1557/adv.2020.150
GaN (21 – 25 meV exciton binding energy). Such properties are typically essential for optoelectronics such as lasers, light emitting diodes and high temperature / high power transistors. Additionally, ZnO is much more resistant to radiation damage which makes it a suitable candidate for space applications.1 In recent years, high surface area metaloxide nanocrystal thin films, particularly TiO2, have been utilized in high efficiency dyesensitized solar cells (DSSCs) where an increased amount of dye molecules could be adsorbed on the surface to harvest sunlight.2 To improve solar cell efficiency
Data Loading...
