Capacitive properties of zinc oxide thin films by radiofrequency magnetron sputtering

Roger Ondo-Ndong,Hans Essone-Obame,Zita Hermance Moussambi,Nathaniel Koumba

doi:10.1007/s40094-018-0309-9

Abstract

The study focused on the production of zinc oxide (ZnO) thin films as a dielectric material for use in metal–insulator–semiconductor capacitors. The objective of this study has demonstrated the frequency dependence of conductivity and capacity. Zinc oxide (ZnO) was thin films deposited by a silicon wavelength sputtering\\magnetron cathode sputtering. The capacitive properties of ZnO zinc oxide were studied at room temperature. The frequency dependence of the conductivity, capacitance and the measured current–voltage (I–V) characteristics of ZnO zinc oxide thin films were studied in the frequency range from 5 kHz to 13 MHz. It is shown that the conductivity is total. Indeed, the measurement of the conductivity in alternating regime obeys the Arrhenius equation. In addition, the measured I–V characteristics of the structures studied at 10 kHz and 10 MHz clearly revealed areas of accumulation, depletion and inversion in the plots. It has been observed that AC conductivity and capacity in the ZnO thin films (ZnO) are frequency dependent. This dependence indicates that the conduction is thermally activated and maintains the correlated barrier of the charge carrier on the localized states as a function of the experimental data. The FBAR (expand) devices with the ZnO films exhibited a pronounced resonance peak centered at 537 MHz with a k2 coupling coefficient of 7%. It found therefore that the impedance matching of the FBAR could be easily achieved simply by controlling the resonance the resonator.

Highlights

Zinc oxide as a dielectric material is the subject of particular attention in the development of micro- and nanotechnologies
The identification of the conduction mechanism depends on both frequency and temperature dependence of electrical conductivity, and Mahmood et al [5] studied the electrical properties of zinc oxide (ZnO) thin films by RF sputtering
It has been observed that AC conductivity in ZnO films follows a σ(ω) ∝ ωs dependence where s ≤ 1 such behavior appears to indicate that hopping is the predominant conduction process

Summary

Introduction

Zinc oxide as a dielectric material is the subject of particular attention in the development of micro- and nanotechnologies. We measured 2.8–3 μm ZnO thin films on samples We confirmed these thicknesses by the determination of the optical properties. After deposition of the zinc oxide, silver dot electrodes were evaporated on the Pt/ZnO/Ti/Pt/Si sample using an electron gun evaporation system to render the structure metal–insulator–semiconductor useful for electrical measurements. These were carried out in a vacuum chamber evacuated at about 10−3 Torr. Measurements of frequency and temperature dependencies of conductivity and capacity were taken using a laboratory configuration for the AC-based electrical test properties. This type of device is one of the instruments to define with precision the characteristics of an electric circuit (impedance measurement, electrical admittance, reflection coefficient, etc.)

Conductivity measurements

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Findings

Conclusion