Journal ArticleDOI
Intrinsic defects in ZnO varistors
TLDR
Theoretical calculations of reaction constants show that the intrinsic donor is the oxygen vacancy, rather than the zinc interstitial as mentioned in this paper, and the depletion of vacancies in the surface region, as the ZnO is cooled from the sintering temperature, is also calculated.Abstract:
Theoretical calculations are presented for equilibrium concentrations of zinc and oxygen vacancies in ZnO. Results are presented at the sintering temperature, and also at room temperature. Theoretical calculations of reaction constants show that the intrinsic donor is the oxygen vacancy, rather than the zinc interstitial. The depletion of vacancies in the surface region, as the ZnO is cooled from the sintering temperature, is also calculated. Homojunction effects which are caused by such depletion are shown to be small.read more
Citations
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Mechanisms behind green photoluminescence in ZnO phosphor powders
Karel Vanheusden,William L. Warren,Carleton H. Seager,David R. Tallant,J. A. Voigt,Bruce E. Gnade +5 more
TL;DR: In this article, the authors explore the interrelationships between the green 510 nm emission, the free-carrier concentration, and the paramagnetic oxygen vacancy density in commercial ZnO phosphors by combining photoluminescence, optical absorption, and electron paramagnetic resonance spectroscopies.
Journal ArticleDOI
ZnO - nanostructures, defects, and devices
TL;DR: ZnO has received much attention over the past few years because it has a wide range of properties that depend on doping, including a range of conductivity from metallic to insulating (including n-type and p-type conductivity), high transparency, piezoelectricity, widebandgap semiconductivity, room-temperature ferromagnetism, and huge magneto-optic and chemical-sensing effects.
Journal ArticleDOI
Blue Luminescence of ZnO Nanoparticles Based on Non‐Equilibrium Processes: Defect Origins and Emission Controls
TL;DR: In this article, high concentrations of defects are introduced into nanoscale ZnO through non-equilibrium processes and resultant blue emissions are comprehensively analyzed, focusing on defect origins and broad controls.
Journal ArticleDOI
Defects in ZnO
TL;DR: A review of defects in ZnO is presented in this paper, with an emphasis on the physical properties of point defects in bulk crystals, and the problem of acceptor dopants remains a key challenge.
Journal ArticleDOI
Blueshift of optical band gap in ZnO thin films grown by metal-organic chemical-vapor deposition
TL;DR: The optical band gap of ZnO thin films deposited on fused quartz by metal-organic chemical-vapor deposition was studied in this article, where X-ray diffraction measurements showed that samples deposited at low temperatures (<450°C) consisted of amorphous and crystalline phases.
References
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Journal ArticleDOI
Nonohmic Properties of Zinc Oxide Ceramics
TL;DR: In this paper, the non-ohmic properties of ZnO ceramics with five additives of Bi2O3, CoO, MnO, Cr2O 3, and Sb 2O3 are studied in relation to sintering temperature, additive content, and temperature dependence.
Journal ArticleDOI
Theory of conduction in ZnO varistors
TL;DR: In this article, a theory was presented which quantitatively accounts for the important features of conduction in ZnO-based metaloxide varistors, which predicts a varistor breakdown voltage of 3.2 V/grain boundary for n0=1017 carriers' cm−3 and T=300 K.
Journal ArticleDOI
The dc voltage dependence of semiconductor grain‐boundary resistance
G. E. Pike,C. H. Seager +1 more
TL;DR: In this article, a model is developed to describe the potential barriers which often occur at grain boundaries in polycrystalline semiconductors, where the resistance of such materials is determined by thermionic emission over these barriers.