A novel film-deposition technique using supercritical fluid was proposed in order to fabricate crystalline oxide thin films on silicon substrates at low substrate temperature. Flow-type deposition apparatus which supplies a metal-organic source on a silicon substrate continuously in the supercritical carbon dioxide (CO₂) atmosphare was manufactured. In this study, Ti(O i-Pr)₂(DPM)₂ was utilized as a starting material for the deposition of titanium oxide (TiO₂). Polycrystalline TiO₂ films (anatase) were depositied on silicon wafers at substrate temperature of 100^oC and CO₂ pressure of 8.0 MPa.

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CAD using FDTD method has been done to ring, square and tetragonal patch microstrip resonators in order to study the tuning of split resonant modes by using dopped Si, magnetic or ferroelectric material. The experimental results are in good agreement with our simulations. Further CAD optimization study for field or temperature sensors and control of resonances will be presented.

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Electromagnetic simulations on materials made from dielectric matrix and ferroelectric particles in symmetry (i.e. cubic) have been studied. Anisotropy properties also have been studied and EM field parameters have been calculated in each case. The temperature and electric field behavior of these materials has been also studied. Simulation results show interested properties for future electron devices applications. Size effects have been studied.

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The high-dielectric perovskite thin films are being developed as capacitor materials for use in on-chip decoupling and tunable devices and next-generation DRAMs. Although some devices have been already commercialized in a limited market, the dielectric thin-film technology is still immature with numerous problems to be solved for further improvement in electrical performance and reliability. In particular, the comprehensive understanding of electrical natures and associated metastable defects inherent in the thin films is essential to serious commercialization. In this report, the current parallel-plate capacitor technology and issues of (BaxSr1-x)TiO3 thin films for high-frequency devices will be discussed.

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We fabricated barium titanate thin films with a very uniform microstructure by the electrophoretic deposition method using a monodisperse suspension of sol-gel-derived BaTiO3 crystalline particles of 10 nm in diameter, and investigated the microstructure and dielectric properties of BaTiO3 ceramic thin films obtained by adding some sintering aids to the precursor films and then sintering them at a temperature below 800C.

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Microwave dielectric properties in (Ba_1-xCa_x)(Mg_1/3Ta_2/3)O₃system were investigated. Permittivity increased and Qf value decreased with Ca substitution. However, compared with A site substitution and B site one in this system, the effect of the former on Qf value was significant small. Also the results of the lattice vibrations analysis followed this effect. The present study showed the importance of substitution site for the improvement of the dielectric properties.

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Integrating and embedding various passive components like a resistor, a capacitor, and an inductor, in one system module, is one of the attractive way to achieve down-sizing, cost-reduction and higher performance in RF wireless communication products such as a cellular phone, a personal digital assistance (PDA) and so on. Aerosol Deposition (AD) method can offer the module with passive components by incorporating different materials with various electrical properties. In this paper, we present the properties of dielectric AD film deposited in various conditions to obtain high dielectric constant and high Q value in high frequency. The electrical properties of the multi-layered capacitor using AD method on resin FR4 substrate are also presented.

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Highly-controlled micrometer-size particle assembling can be achieved by a micro-electrophoretic deposition (m-EPD) process with a micro counter electrode or an interdigitated microarray electrode. In this study, monodisperse polystyrene microspheres were selected as a test example. With the use of this m-EPD process, we successfully fabricated microdot or microline consisting of highly ordered polystyrene microspheres.

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Electrophoretic deposition (EPD) is a colloidal process wherein ceramic bodies are directly shaped from a stable colloid suspension by a dc electric field. In this study, an attempt was made to investigate the role of phosphate esters on the stability of alumina ethanol suspensions and the corresponding effects on the electrophoretic deposition characteristics. The use of phosphate esters as dispersants enabled cathodic deposition of alumina particles with high green density. The mechanism of particle charging was investigated by measuring deposition yield, suspension pH, conductivity and zeta-potential at various experimental conditions.

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