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CaZrO3 (CZO) thin films were deposited on Pt/Ti/SiO2/Si substrates at 450 °C by radio-frequency magnetron sputtering technology. The microstructures and dielectric properties of CZO thin films were investigated. X-ray diffraction analysis reveals that the perovskite orthogonal CZO phase would be promoted by a higher O2 partial pressure in the flow ratio of O2/Ar after thin films were annealed at 700 °C for 3 h in air. The films prepared under the flow ratio of O2/Ar (20:40, 30:40 and 40:40) show the main perovskite crystal phase of CaZrO3 with a small amount of Ca0.2Zr0.8O1.8. The main crystal phase was Ca0.2Zr0.8O1.8 when the film was deposited under an O2/Ar ratio of 40:10. The annealed film with a 40:40 O2/Ar ratio exhibits a dielectric performance with a high dielectric constant (εr) of 25 at 1 MHz, a temperature coefficient of permittivity of not more than 122.7 ppm/°C from 0 °C to 125 °C, and a low leakage current density of about 2 × 10−7 A/cm2 at 30 V with an ohmic conduction mechanism. [ABSTRACT FROM AUTHOR]

CaZrO3 (CZO) thin films were deposited on Pt/Ti/SiO2/Si substrates at 450 °C by radio-frequency magnetron sputtering technology. The microstructures and dielectric properties of CZO thin films were investigated. X-ray diffraction analysis reveals that the perovskite orthogonal CZO phase would be promoted by a higher O2 partial pressure in the flow ratio of O2/Ar after thin films were annealed at 700 °C for 3 h in air. The films prepared under the flow ratio of O2/Ar (20:40, 30:40 and 40:40) show the main perovskite crystal phase of CaZrO3 with a small amount of Ca0.2Zr0.8O1.8. The main crystal phase was Ca0.2Zr0.8O1.8 when the film was deposited under an O2/Ar ratio of 40:10. The annealed film with a 40:40 O2/Ar ratio exhibits a dielectric performance with a high dielectric constant (εr) of 25 at 1 MHz, a temperature coefficient of permittivity of not more than 122.7 ppm/°C from 0 °C to 125 °C, and a low leakage current density of about 2 × 10−7 A/cm2 at 30 V with an ohmic conduction mechanism.

SiO 2 thin film was deposited on quartz glass substrate with radio frequency (RF) magnetron sputtering. The effects of O 2 /Ar flow ratio and heat treatment on the O/Si molar ratio, surface morphology and optical properties of the film were investigated. SiO 2 film was composed of amorphous nanoparticles. When the O 2 /Ar flow ratio increased from 30% to 60%, the film's O/Si ratio increased continuously from severe O-deficiency 1.68:1 to 1.93:1, close to the stoichiometric ratio 2:1. Meanwhile, the particles' average size decreased and became more uniform, and the surface roughness decreased with the O 2 /Ar flow ratio increase. And the film's refractive index and absorptivity decreased continuously, while the coated glass substrate's average transmittance (hereinafter referred to as the film's transmittance) within 300–1100 nm increased from 91.7% to 92.9% continuously. Heat treatment at 550 °C resulted in an obvious agglomeration of the nanoparticles, reduced the refractive index of the film and improved its transmittance. [ABSTRACT FROM AUTHOR]

Abstract: The deposition of rutile phase TiO2 films on unheated substrates by radio frequency magnetron sputtering is elaborated. The effect of total pressure and O2/Ar flow ratio on the growth of rutile film on different substrates has been studied thoroughly. The development of crystalline phase along with film deposition rate, surface morphology, optical transmission and band gap were also investigated for various growth conditions. It was found that the rutile phase crystallinity increased with decrease in total pressure and increase in O2 flow. In addition, the grown rutile films have interesting optical characteristics such as high transmittance (~85%) and high refractive index (~2.7) with a band gap about 3.2eV. [Copyright &y& Elsevier]

Abstract: Hafnium dioxide (HfO2) thin films were deposited on a quartz substrate by RF reactive magnetron sputtering. The influence of O2/Ar flow ratio on the deposition rate, structure and optical properties of HfO2 thin films were systematically studied using X-ray diffraction (XRD), scan electron microscopy (SEM) and UV–visible spectroscopy. The results show that the deposition rate decreases obviously when the O2/Ar flow ratio increases from 0 to 0.25 and then, decreases little as the O2/Ar flow ratio further increases to 0.50. The HfO2 thin films prepared are all polycrystalline with a monoclinic phase. The thin film deposited with pure argon shows a preferential growth and has considerably improved crystallinity and much larger crystallite size. Meanwhile, after oxygen is introduced into the deposition, the thin films prepared have random orientation, weakened crystallinity and smaller crystallite size. The refractive index is higher for the thin film deposited without oxygen and increases as the O2/Ar flow ratio increases from 0.25 to 0.50. The band gap energy of the thin film increases with an increasing O2/Ar flow ratio. [ABSTRACT FROM AUTHOR]