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Abstract: In this work, we report electrical measurements of CaCu3Ti4O12 (CCTO) and (BaTiO3–barium titanate, BTO) thick films. The dielectric constant (K) measurements shows that the BTO thick film present a higher K compared to CCTO compound, in the range of frequencies under study. However, for the composite film (CCTO50 and CCTO50T films), one has an unexpected result; the dielectric constant is higher for all the frequencies under study. The BTO–CCTO composite films do not obey the empirical mixing rule. These electric properties were also studied in the temperature range of 80–300K. For the CCTO film, two relaxation processes were detected. The calculated activation energy was around 0.51eV for temperatures above 200K. One second relaxation process was observed on cooling below 200K with activation energy around 0.061eV. For the composite film CCTO50T, both relaxation processes are still present. Therefore, these measurements confirm the potential use of such materials for small high dielectric planar devices. These films are also attractive for capacitor applications and certainly for microelectronics, microwave devices (cell mobile phones, for example), where the miniaturization of the devices is crucial. [Copyright &y& Elsevier]

In this paper, we will study the effect of the presence of CCTO (CaCu3Ti4O12) in the dielectric permittivity and loss of barium titanate (BTO-BaTiO3) thick films. These films were prepared in two layers geometry using the screen printing technique on Al2O3 substrates. Mechanical alloying followed by the solid state procedure has been used successfully to produce powders of CCTO (CaCu3Ti4O12) used in the films. We also look at the effect of the grain size of the BTO and CCTO in the final properties of the film. These samples were studied using X-ray diffraction, scanning electron microscopy (SEM), Raman and infrared spectroscopies. We also did a study of the dielectric permittivity (K) and loss (D) in the medium-frequency (MF) range (100 Hz–1 MHz), of the films. The role played by firing process in the film preparation and the crystallite size of CCTO and BTO in the dielectric constant and structural properties of the films are discussed. Therefore, these measurements confirm the potential use of such materials for small high dielectric planar devices. These films are also attractive for capacitor applications and certainly for microelectronics, microwave devices (cell mobile phones, for example), where the miniaturization of the devices is crucial. [Copyright &y& Elsevier]

In this paper we will study the effect of the presence of hydroxyapatite (HA—Ca10(PO4)6(OH)2) on the dielectric permittivity and losses of the barium titanate (BTO—BaTiO3) thick films. These films were prepared in two layers geometry using the screen printing technique on Al2O3 substrates. Mechanical alloying has been used successfully to produce nanocrystalline powders of hydroxyapatite (HA) used in the films. We also look for the effect of the grain size of the BTO and HA on the final properties of the film. The samples were studied using X-ray diffraction, scanning electron microscopy (SEM), Raman and infrared spectroscopies, dielectric permittivity and losses measurements. The study of the dielectric permittivity and losses was done in the radio-frequency range (100 Hz–10 MHz). The role played by the firing process in the film preparation and the crystallite size of HA and BTO on the dielectric constant and structural properties of the films are discussed. [Copyright &y& Elsevier]