The Role of Interfacial Microstructure in ZnO Varistor Materials

ZnO/PrCoOx and ZnO/PrCoOx/ZnO junctions have been fabricated by sputtering as a model of a single grain boundary in a ceramic ZnO varistor. The relations between barrier parameters and varistor characteristics were investigated using voltage-current (V-I) capacitance-voltage (C-V), and deep-level transient spectroscopy (DLTS) measurements. The varistor voltage of the junctions increases as the donor density (ND) of the ZnO film decreases. The interface states vary according to the method of ZnO sputtering. A clear correlation has been established between the α value and the interface states. The highest α value is obtained when ND is ≃ 1018 cm−3, the interface level is 0.70 eV, and the breakdown voltage is 3–4 V. Oxygen is effective on control of ND in ZnO and the interface states. Al added as a dopant is also effective in terms of its ability to increase ND in ZnO. However, Al doping was found to degrade the interface states and increase the leakage current.

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The role of thermal annealing in changing the interfacial microstructure of Ge-ZnSe heterojunctions

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/10/4/014 ◽

1977 ◽

Vol 10 (4) ◽

pp. 499-508 ◽

Cited By ~ 1

Author(s):

A W Brinkman ◽

D L Kirk

Keyword(s):

Thermal Annealing ◽

Interfacial Microstructure

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The Determining Role of Nb Interlayer on Interfacial Microstructure and Mechanical Properties of Ti/Steel Clad Plate by Vacuum Rolling Cladding

Materials ◽

10.3390/ma11101983 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1983 ◽

Cited By ~ 5

Author(s):

Guang-ming Xie ◽

De-han Yang ◽

Zong-an Luo ◽

Ming Li ◽

Ming-kun Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Shear Strength ◽

Heating Temperature ◽

Interfacial Microstructure ◽

Electron Probe Micro Analyzer ◽

Average Shear Strength ◽

Average Shear ◽

Nb Interlayer

We elucidate here the determining role of Nb interlayer on mechanical properties of Ti/steel clad plate fabricated by vacuum rolling cladding (VRC) as a function of different heating temperatures. A critical analysis on the clad interface via electron probe micro-analyzer, X-ray diffractometer and shear testing were conducted to investigate the influence of TiC, Fe-Nb and TiFe compounds and Nb-Ti solid solution on microstructural evolution and shear properties of Ti/steel clad plate. The inter-diffusion between Ti, C and Fe was effectively restrained by adding the Nb interlayer at heating temperature of 800 °C, and average shear strength of 279 MPa was achieved. With increase of heating temperature, Nb-Ti solid solution was formed at the Ti/Nb interface, which reduced mechanical properties of clad plate at 900 °C. At 1000 °C, TiC and Nb-Fe compounds and Nb-Ti solid solution were formed at the interface, and minimum average shear strength of 152 MPa was achieved. The detailed analysis on the clad interface suggested that ideal shear strength can be obtained through the addition of Nb interlayer and selecting appropriate heating temperature.

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