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We present the influences of radio-frequency (RF) power on the optical, electrical, mechanical, and structural properties of Ga-doped zinc oxide (GZO) thin films by RF magnetron sputtering at room temperature. GZO thin films were grown on unheated glass and silicon substrates using radio-frequency (RF) magnetron sputtering method with different RF powers (from 60 W to 160 W). The optical properties of the GZO thin film were determined by a UV–vis spectrophotometer. The residual stress in GZO films were measured by a home-made Twyman–Green interferometer with the fast Fourier transform (FFT) method. The surface roughness of GZO films were measured by a microscopic interferometry. The microstructure, composition and crystal orientation of the GZO films were determined by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). This paper revealed that the optical, electrical, mechanical, and structural properties of GZO thin film are subject to the RF power. For the optical spectrum measurement, an average optical transmittance in the visible region of the spectra of 85% was obtained. For the characteristic measurements, all the GZO thin films deposited by RF magnetron sputtering have compressive stress at different RF powers. A minimum residual stress of 0.24 GPa is found at the RF power of 140 W. A four-point probe method was used to measure the resistivity of the GZO thin films with different powers, the results indicate that the resistivity increases with increasing of RF power. In addition, the root-mean-square (RMS) surface roughness of GZO thin films slightly increases as the RF power is increasing. We have also compared the results with the relevant literatures. [ABSTRACT FROM AUTHOR]

The NiFe thin films were prepared at room temperature by DC sputtering technique from a NiFe target onto silicon wafer, NBK7 and STIM35 glass substrates. The optimal deposition condition of NiFe thin films was obtained to be used for high density magnetic recording applications. The film thickness was determined by the SEM measurement. The electrical resistivity of the NiFe thin film with a thickness of 240 nm was \(1.17 \times 10^{{-5}}\Omega \) -cm. The average residual stress and thermo-mechanical parameters were determined by the fast Fourier transform (FFT) method. The average residual stresses on two different substrates are −50 ± 2 MPa. The residual stress versus substrate temperature relation is a linear correlation after heating from room temperature to 100 °C. A double substrate technique was used to determine the thermal expansion coefficients and biaxial modulus of the NiFe thin films. The experimental results show that the thermal expansion coefficient of the NiFe thin films is \(6.44 \times 10^{-6}\,~^{\circ}{\rm C}^{-1}\) . The biaxial modulus is 779 GPa. The surface roughness was evaluated by using a microscopic interferometer. The root-mean-square roughness of the NiFe thin films were 1.350 nm for NBK7, 1.403 nm for STIM35 and 1.387 nm for silicon wafer. [ABSTRACT FROM PUBLISHER]