Next Article in Journal
Upgrading the Performance of Cholesteric Liquid Crystal Lasers: Improvement Margins and Limitations
Previous Article in Journal
Development of Highly Repellent Silica Particles for Protection of Hemp Shiv Used as Insulation Materials
Article Menu
Issue 1 (January) cover image

Export Article

Open AccessArticle
Materials 2018, 11(1), 3; https://doi.org/10.3390/ma11010003

Zno Micro/Nanostructures Grown on Sapphire Substrates Using Low-Temperature Vapor-Trapped Thermal Chemical Vapor Deposition: Structural and Optical Properties

1
Institute of Photonic System, National Chiao Tung University, Tainan City 71150, Taiwan
2
Institute of Imaging and Biomedical Photonics, National Chiao Tung University, Tainan City 71150, Taiwan
*
Author to whom correspondence should be addressed.
Received: 13 November 2017 / Revised: 17 December 2017 / Accepted: 18 December 2017 / Published: 21 December 2017
(This article belongs to the Section Structure Analysis and Characterization)
View Full-Text   |   Download PDF [4164 KB, uploaded 21 December 2017]   |  

Abstract

In this research, the Zn(C5H7O2)2·xH2O-based growth of ZnO micro/nanostructures in a low temperature, vapor-trapped chemical vapor deposition system was attempted to optimize structural and optical properties for potential biomedical applications. By trapping in-flow gas molecules and Zinc vapor inside a chamber tube by partially obstructing a chamber outlet, a high pressure condition can be achieved, and this experimental setup has the advantages of ease of synthesis, being a low temperature process, and cost effectiveness. Empirically, the growth process proceeded under a chamber condition of an atmospheric pressure of 730 torr, a controlled volume flow rate of input gas, N2/O2, of 500/500 Standard Cubic Centimeters per Minute (SCCM), and a designated oven temperature of 500 °C. Specifically, the dependence of structural and optical properties of the structures on growth duration and spatially dependent temperature were investigated utilizing scanning electron microscopy, X-ray diffraction (XRD), photoluminescence (PL), and ultraviolet-visible transmission spectroscopy. The experimental results indicate that the grown thin film observed with hexagonal structures and higher structural uniformity enables more prominent structural and optical signatures. XRD spectra present the dominant peaks along crystal planes of (002) and (101) as the main direction of crystallization. In addition, while the structures excited with laser wavelength of 325 nm emit a signature radiation around 380 nm, an ultraviolet lamp with a wavelength of 254 nm revealed distinctive photoluminescence peaks at 363.96 nm and 403.52 nm, elucidating different degrees of structural correlation as functions of growth duration and the spatial gradient of temperature. Transmittance spectra of the structures illustrate typical variation in the wavelength range of 200 nm to 400 nm, and its structural correlation is less significant when compared with PL. View Full-Text
Keywords: low temperature process; vapor-trapped CVD; structural and optical characterization low temperature process; vapor-trapped CVD; structural and optical characterization
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Hu, P.-S.; Wu, C.-E.; Chen, G.-L. Zno Micro/Nanostructures Grown on Sapphire Substrates Using Low-Temperature Vapor-Trapped Thermal Chemical Vapor Deposition: Structural and Optical Properties. Materials 2018, 11, 3.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top