Admittance and Photoadmittance Spectroscopy of Zinc Oxide Layers Grown on p-Si Substrates by Spin Coating Method

In this work, the dielectric response of ZnO thin films has been studied over a temperature range of 200 K - 550 K. The dielectric response of polycrystalline ZnO thin films in the frequency domain was measured from 42 Hz - to 5 MHz with a small AC signal amplitude at different temperatures. Influence of the light on conductivity has been also investigated. A universal power law relation was brought into picture to explain the frequency dependence of AC conductivity. The temperature dependence of AC conductivity was analyzed in detail. The activation energy obtained from the temperature dependence of AC conductivity was attributed to the shallow trap-controlled space charge conduction in the bulk of the sample.

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Hydrogen Gas Sensing Characterizations Based on Nanocrystalline SnO2 Thin Films Grown on SiO2/Si and Al2O3 Substrates

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.268.244 ◽

2017 ◽

Vol 268 ◽

pp. 244-248

Author(s):

Abu Hassan Haslan ◽

Imad Hussein Kadhim

Keyword(s):

Thin Films ◽

Room Temperature ◽

Gas Sensing ◽

Sol Gel ◽

Hydrogen Gas ◽

Rutile Structure ◽

Nanoparticle Distribution ◽

Si Substrates ◽

Coating Method ◽

Different Temperatures

High-quality nanocrystalline (NC) SnO2 thin films were grown on SiO2/Si and Al2O3 substrates using sol–gel spin coating method. The structural properties, surface morphologies and gas sensing properties of the NC SnO2 were investigated. XRD measurements showed a tetragonal rutile structure and the diffraction peaks for NC SnO2 thin films grown on Al2O3 substrates outperformed those of NC SnO2 films grown on SiO2/Si substrates. The surface morphology of the annealed SnO2 thin films at 500 °C appeared as polycrystalline with uniform nanoparticle distribution. Hydrogen (H2) gas sensing performance of the NC SnO2 was examined for H2 concentrations ranging from 150 ppm to 1000 ppm at different temperatures (room temperature, 75 and 125 °C) for over 50 min. The room temperature sensitivities for H2 gas sensors based on NC SnO2 thin films grown on Al2O3 and SiO2/Si substrates was 2570% and 600%, respectively upon exposure to 1000 ppm of H2 gas. While the sensitivity values at 125 °C increased to 9200% and 1950%, respectively.

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Optical and Electrical Properties of ZnO Thin Films Grown by Sol-Gel Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.200.14 ◽

2013 ◽

Vol 200 ◽

pp. 14-21 ◽

Cited By ~ 2

Author(s):

Waclaw Bala ◽

Yurij Zorenko ◽

Volodymyr Savchyn ◽

Taras Voznyak ◽

Kazimierz Paprocki ◽

...

Keyword(s):

Thin Films ◽

Electrical Response ◽

Sol Gel ◽

Zno Thin Films ◽

Thickness Variation ◽

Coating Method ◽

Crystallinity Parameters ◽

Different Temperatures ◽

P Type ◽

Quartz Substrates

The ZnO thin films have been produced on p-type Si and quartz substrates by the spin-coating method and after deposition were heated at different temperatures in the range from 650K to 850K. The photoluminescence (PL) and cathodoluminescence (CL) measurements were carried out at temperature range 12K-350K. I-V, C-V measurements were performed on the Al/ZnO/Si/Al structures at different temperatures. The structural properties of the ZnO thin films were carried out using x-ray and SEM method. The effects of the thickness variation and annealing temperature on the crystallinity parameters were observed. The electrical response of grains, grain boundaries, and contacts of the ZnO film was obtained.

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Temperature dependence of growth orientation and surface morphology of Li-doped ZnO thin films on SiO2/Si substrates

Crystal Research and Technology ◽

10.1002/crat.200800007 ◽

2008 ◽

Vol 43 (9) ◽

pp. 970-974 ◽

Cited By ~ 1

Author(s):

E. M. El-Maghraby

Keyword(s):

Thin Films ◽

Surface Morphology ◽

Temperature Dependence ◽

Zno Thin Films ◽

Growth Orientation ◽

Si Substrates ◽

Doped Zno

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Temperature dependence of ZnO thin films grown on Si substrate

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-007-9402-6 ◽

2007 ◽

Vol 19 (8-9) ◽

pp. 749-754 ◽

Cited By ~ 6

Author(s):

Y. Y. Kim ◽

C. H. Ahn ◽

S. W. Kang ◽

B. H. Kong ◽

S. K. Mohanta ◽

...

Keyword(s):

Thin Films ◽

Temperature Dependence ◽

Zno Thin Films ◽

Si Substrate

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Effects of the Sputtering Time of AlN Buffer Layer on the Quality of ZnO Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.1117 ◽

2014 ◽

Vol 881-883 ◽

pp. 1117-1121 ◽

Cited By ~ 1

Author(s):

Xiang Min Zhao

Keyword(s):

Thin Films ◽

Buffer Layer ◽

Rf Magnetron Sputtering ◽

Buffer Layers ◽

Zno Thin Films ◽

Zno Films ◽

Si Substrates ◽

Atomic Force ◽

Structure Morphology ◽

Aln Buffer

ZnO thin films with different thickness (the sputtering time of AlN buffer layers was 0 min, 30 min,60 min, and 90 min, respectively) were prepared on Si substrates using radio frequency (RF) magnetron sputtering system.X-ray diffraction (XRD), atomic force microscope (AFM), Hall measurements setup (Hall) were used to analyze the structure, morphology and electrical properties of ZnO films.The results show that growth are still preferred (002) orientation of ZnO thin films with different sputtering time of AlN buffer layer,and for the better growth of ZnO films, the optimal sputtering time is 60 min.

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