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Ceramic Films (ceramic + film)
Selected AbstractsMultilayer Construction with Various Ceramic Films for Electronic Devices Fabricated by Aerosol DepositionINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 6 2006Hironori Hatono Aerosol deposition (AD) is applicable as a fabrication technology for microstructures comprising different materials. We used this method for electronic devices that consist of ceramic films and metal electrodes. Various ceramic thick films (5,50 ,m thickness), for example, Al2O3, 2MgOˇSiO2, and BaTiO3, were deposited on substrates using room-temperature aerosol deposition. The dielectric constant of BaTiO3 was 78 at 1 MHz. Multilayer constructions with ceramic films and copper electrodes were obtained using aerosol deposition and sputtering. During deposition, photoresist film masks were applied to produce patterns of ceramic films and connections between upper and lower electrodes through the ceramic films. [source] Fabrication of Thick (>10 ,m) GeO2 Ceramic Films by a Facile Liquid Phase Deposition ProcessJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2007Chengbin Jing GeO2 thick (>10 ,m) ceramic films were fabricated by facile liquid-phase deposition. The solubility of hexagonal GeO2 in water was increased ten times on adding aqueous ammonia at 70°C because of the formation of soluble Ge5O112,. With the addition of sulfuric acid, the alkaline GeO2,aqueous ammonia was neutralized, leading to the transformation of Ge5O112, into GeO2 precipitates. When the H2SO4/NH4OH molar ratio was higher than 11.7, immediate precipitation of GeO2 particles took place in the solution with no GeO2 particles deposited on the substrate. When the H2SO4/NH4OH molar ratio was decreased from 5.85 to 0.29, the precipitation process was retarded, leading to the gradual growth of uniform hexagonal GeO2 thick films on the substrates. The compactness of the film increased with a decrease in the H2SO4/NH4OH molar ratio. The growth of the GeO2 crystal film followed the Bravais,Freidel,Donnay,Harker and Hartman,Perdok models, and the cubic GeO2 particles with a size of about 10 ,m were finally formed on the film. No GeO2 precipitate was produced on the substrate when the GeO2,aqueous ammonia had an excessively low H2SO4/NH4OH molar ratio (,0.15) because the GeO2 solute did not reach the saturation level and the nucleation process could not take place on the substrate. The particles on the film surface deposited from the solution with an H2SO4/NH4OH molar ratio of 0.29 exhibited a nanopore structure. An initial study using this film as a support for KNO3 catalyst was carried out and the result revealed that the catalyst showed good catalytic activity of diesel soot oxidation. [source] The Electrochemical Properties of Co(TPP), Tetraphenylborate Modified Glassy Carbon Electrode: Application to Dopamine and Uric Acid AnalysisELECTROANALYSIS, Issue 5 2006Yunlong Zeng Abstract We report the combination of the charge repelling property of tetraphenyl-borate (TPB) anion and the electrooxidation catalytic effect of cobalt(II) tetrakisphenylporphyrin (CoTPP) embedded in a sol gel ceramic film to develop a modified glassy carbon electrode (CoTPP-TPB-SGGCE) for the simultaneous determination of dopamine (DA) and uric acid (UA). The optimized CoTPP-TPB-SGGCE shows excellent sensitivity and selectivity for the DA and UA analysis. As high as 2000 fold acceptable tolerance of ascorbic acid (AA) for the determination of trace DA and UA is reached. In the presence of 0.10,mM AA, the linear concentration range for DA is from 6.0×10,8 to 2.5×10,5,M, and the detection limit is 2.0×10,8,M. For UA, the linear concentration range is from 1.0×10,7 to 3.5×10,5,M, and the detection limit is 7.0×10,8,M. Our study has also demonstrated that the novel CoTPP-TPB-SGGCE shows high stability and reliability. For 6.00,,M DA and UA, a total of 12,measurements were taken in one week, and the relative standard deviation is 2.05% and 2.68% respectively. No obvious shift of peak current and peak potential is observed over a three-month lifetime test. The response of the sensor is very quick and response time is approximately 1,s. Satisfactory results are also achieved when the CoTPP-TPB-SGGCEs being used to detect the DA and UA in human urine samples. [source] Thick Nb-Doped Bismuth Titanate Film with Controllable Grain OrientationJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2006Weiwu Chen In the current work, we reported a potential approach to obtain thick ceramic films with controllable grain orientation based on magnetic alignment and polymerization techniques. The slurry containing 40 vol% Bi4Ti2.96Nb0.04O12 (BINT) ceramic powder, monomer, initiator, and catalyst was drop coated on a Pt substrate and then moved into a vertical 10 T magnetic field. In 1,2 min, the ceramic particles were aligned by a strong magnetic force in slurry and then in situ locked by polymerization on the substrate. After sintering at 1000°C, a BINT ceramic film (50,80 ,m in thickness) with a highly a/b plane orientation was obtained. Theoretically, the grain orientation in the films can be easily controlled by adjusting the magnetic field direction. This approach is readily applicable to other materials with a non-cubic structure and is expected to facilitate the fast preparation of grain-oriented thick films. [source] Effects of Thermal Annealing on the Structure of Ferroelectric Thin FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2006Jiang-Li Cao The effects of thermal annealing on the structure of polycrystalline Pb(Zr0.3Ti0.7)O3 (PZT) ferroelectric thin films prepared by chemical solution deposition on Pt/TiOx electrode stacks were studied using scanning electron microscopy, transmission electron microscopy (TEM), and grazing incidence X-ray specular and diffuse reflectivity of synchrotron radiation. The stratified multilayered structure and element diffusions in the sample were characterized by TEM. Global statistical structural parameters including the density, surface or interface roughness and thickness of each layer in the samples were obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayer model of PZT/Pt/TiOx/SiO2. The results showed that the PZT surface and PZT/Pt interface roughness changed slightly during thermal annealing in oxygen at 700°C. By contrast, the density increase of the PZT ceramic and density decrease of the Pt-bottom electrode during annealing were observed. A high density value of the PZT ceramic film after the annealing was found, up to 99.8% of the theoretical value of the corresponding bulk ceramics. The density changes of the PZT and Pt layers were further confirmed by X-ray diffuse reflectivity. The influences of the annealing treatment on the density changes of the PZT and Pt layers were attributed to the further densification of the PZT ceramic and incorporation of light elements such as Zr, Ti and O from the neighboring layers into the Pt layer, respectively, as discussed in correlation with the TEM analyses. [source] Microstructural and Mechanical Investigations on Porcelain-Fused-to-Metal in Multilayer SystemADVANCED ENGINEERING MATERIALS, Issue 4 2010Adele Carradō Results on porcelain-fused-to-metal (PFM) technique of ceramic films for biomedical applications on metal substrate are reported. The coating of metallic implants with bio-ceramic films (glassy and opaque ceramic) was proposed to be a solution for combining the mechanical properties of the metallic material with the bioactive character of the ceramic layer, leading to a better integration of the entire implant. The aim of this paper is to determine a stress field distribution by a non-destructive method as high-energy synchrotron X-ray diffraction in energy dispersive in the metal and glass ceramic bulk as well as at metal,opaque ceramic interface in PFM three layers sample. Tensile stresses were found in palladium substrate and compressive state in glass ceramic coating. Moreover thermal stresses induced by PFM coating at the interfaces were calculated by analytical mathematical model, confirming that the stresses induced, due to the selection of the materials, are low. Finally, the micro-structural and chemical characteristics of glassy and opaque bio-ceramic coatings on palladium alloy substrate were investigated and no inter-diffusion area between metal and ceramic could be detected as well as non-homogeneity in the interface ceramic. [source] Multilayer Construction with Various Ceramic Films for Electronic Devices Fabricated by Aerosol DepositionINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 6 2006Hironori Hatono Aerosol deposition (AD) is applicable as a fabrication technology for microstructures comprising different materials. We used this method for electronic devices that consist of ceramic films and metal electrodes. Various ceramic thick films (5,50 ,m thickness), for example, Al2O3, 2MgOˇSiO2, and BaTiO3, were deposited on substrates using room-temperature aerosol deposition. The dielectric constant of BaTiO3 was 78 at 1 MHz. Multilayer constructions with ceramic films and copper electrodes were obtained using aerosol deposition and sputtering. During deposition, photoresist film masks were applied to produce patterns of ceramic films and connections between upper and lower electrodes through the ceramic films. [source] Fabrication of Thick (>10 ,m) GeO2 Ceramic Films by a Facile Liquid Phase Deposition ProcessJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2007Chengbin Jing GeO2 thick (>10 ,m) ceramic films were fabricated by facile liquid-phase deposition. The solubility of hexagonal GeO2 in water was increased ten times on adding aqueous ammonia at 70°C because of the formation of soluble Ge5O112,. With the addition of sulfuric acid, the alkaline GeO2,aqueous ammonia was neutralized, leading to the transformation of Ge5O112, into GeO2 precipitates. When the H2SO4/NH4OH molar ratio was higher than 11.7, immediate precipitation of GeO2 particles took place in the solution with no GeO2 particles deposited on the substrate. When the H2SO4/NH4OH molar ratio was decreased from 5.85 to 0.29, the precipitation process was retarded, leading to the gradual growth of uniform hexagonal GeO2 thick films on the substrates. The compactness of the film increased with a decrease in the H2SO4/NH4OH molar ratio. The growth of the GeO2 crystal film followed the Bravais,Freidel,Donnay,Harker and Hartman,Perdok models, and the cubic GeO2 particles with a size of about 10 ,m were finally formed on the film. No GeO2 precipitate was produced on the substrate when the GeO2,aqueous ammonia had an excessively low H2SO4/NH4OH molar ratio (,0.15) because the GeO2 solute did not reach the saturation level and the nucleation process could not take place on the substrate. The particles on the film surface deposited from the solution with an H2SO4/NH4OH molar ratio of 0.29 exhibited a nanopore structure. An initial study using this film as a support for KNO3 catalyst was carried out and the result revealed that the catalyst showed good catalytic activity of diesel soot oxidation. [source] Thick Nb-Doped Bismuth Titanate Film with Controllable Grain OrientationJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2006Weiwu Chen In the current work, we reported a potential approach to obtain thick ceramic films with controllable grain orientation based on magnetic alignment and polymerization techniques. The slurry containing 40 vol% Bi4Ti2.96Nb0.04O12 (BINT) ceramic powder, monomer, initiator, and catalyst was drop coated on a Pt substrate and then moved into a vertical 10 T magnetic field. In 1,2 min, the ceramic particles were aligned by a strong magnetic force in slurry and then in situ locked by polymerization on the substrate. After sintering at 1000°C, a BINT ceramic film (50,80 ,m in thickness) with a highly a/b plane orientation was obtained. Theoretically, the grain orientation in the films can be easily controlled by adjusting the magnetic field direction. This approach is readily applicable to other materials with a non-cubic structure and is expected to facilitate the fast preparation of grain-oriented thick films. [source] | ||||||||||