Electrical properties and surface morphology of SiO _x-Pt nano-composite thin films

Recently, ceramic metals (cermets) have been widely investigated for use as embedded resistor materials. In this study, SiO-Pt nano-composite cermets were developed to control the resitivity and temperature coefficients of resistance (TCR) of embedded thin film resistors. The SiO-Pt nanocomposite was prepared by the co-sputtering of a SiO _x target and Pt chips onto glass. The experiments were conducted Pt concentrations in order to find the optimum conditions to achieve a high resistivity and low TCR. The electrical properties of the sputtered SiO-Pt thin films were investigated by probe station and their crystal structures were observed by X-Ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). The surface morphology was observed by field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HR-TEM). It was found that the Pt particles with a size of 3∼5 nm were uniformly dispersed in the SiO matrix. A stable resistivity value of 26000∼57000 μΩcm and TCR value of -197∼-322 ppm/K were obtained at 3.5∼3.7 at.% Pt.