A measurement method of thermal conductivities of Cu thin films was devised from the temperature distributions of substrate surfaces. The substrate was prepared to have a prismatic bar shape, and was deposited with Cu thin films using sputtering. Two metal coated surfaces of specimens were brought into contact to maintain the insulated boundary condition. Specimens were heated with constant temperature at both ends. The temperature distributions were measured from the back surface of substrate using a radiation thermometry.

The thermal conductivities of Cu thin films were found to be much lower than those of bulk materials. Wiedemann-Franz law could be applied to thin films produced in this study. Thermal conductivity was also estimated from the resistivity of thin film and Lorenz number of bulk material.

Tungsten-tellurite glass thin films were fabricated by radio-frequency (rf) magnetron sputtering method at various processing parameters such as substrate temperatures, Ar/O2 processing gas flow ratio, processing pressure, and rf power from a 70TeO2-30WO3 target fabricated by solid–state sintering method. The effects of processing parameters on the growth rate, the surface morphologies, the crystallinity, and refractive indices of thin films were investigated using atomic force microscopy, X-ray diffractometer, scanning electron microscopy, and UV spectrometer. Amorphous glass thin films with a surface roughness of 4∼6 nm were obtained only at room temperature and crystalline phase were observed in all as-deposited thin films prepared at above the room temperature. The deposition rate strongly depends on the processing parameters. It increases as the rf power increases and the processing pressure decreases. Especially, it changes remarkably as varying the Ar/O2 gas flow ratio from 40sccm/0sccm to 0sccm/40sccm. When the films were formed in pure Ar atmosphere it shows a deposition rate of ∼0.2 μm /h, whereas ∼1.5 μm/h when the films was formed in pure O2 atmosphere.

ZnO films were produced on the Si(100) and sapphire(0001) wafers by RF magnetron sputtering in terms of processing variables such as substrate temperature and RF power. The stress in films was obtained from the Stoney's formula using a laser scanning device. The stress levels in the films showed the range from ∼40MPa to ∼-1100MPa depending on processing variables.

SEM was employed to characterize the microstructure of the films. As the substrate temperature increased, the film surface became rougher and the films showed coarser grains. The optical property of the films was studied by PL measurements. At the highest substrate temperature 800°C the film exhibited sharper UV peaks unlike other conditions.

Epitaxial PbZr0.5Ti0.5O3 (PZT) thin films were grown on top of a SrRuO3 epitaxial electrode layer on a (100) SrTiO3 substrate by the chemical solution deposition method at various temperatures. The microstructure of the PZT thin films was investigated by x-ray diffraction and transmission electron microscopy, and the ferroelectric properties were measured using the Ag/PZT/SRO capacitor structure. In the PZT thin film annealed at low temperature (450 °C/1h), both the perovskite PZT phase at the film/substrate interface and the fluorite PZT phase in the upper region of the film were obtained. It exhibited nonferroelectric properties. The PZT thin film annealed at temperature as low as 525 °C had only a perovskite tetragonal phase and the epitaxial orientational relationship of (001)[010]PZT∥(001)[010]SRO∥(001)[010]STOwith the substrate, and shows a ferroelectric property. The remnant (Pr) and saturation polarization (Ps) density of the sample annealed at 600 °C/1h were measured to be Pr ˜ 51.4 μC/cm2 and Ps ˜ 62.1 μC/cm2 at 5 V, respectively. The net switched polarization dropped only to 98% of its initial value after 7 × 108 fatigue cycles.

Metal matrix composites (MMC's) are known to have wide applications in parts of transportation devices such as automobiles and aircraft. Al matrix composites using SiC particles as reinforcements are especially spotlighted because of low cost, superior specific modulus, specific strength, wear resistance and high temperature stability. However, Al4C3 formed by the interfacial reaction between Al and SiC weakens the interfacial bonding strength. It is also known to be unstable in the water-soluble atmosphere.

In this study, the passive oxidation of SiC powder is used as protective layer against the reaction between the Al matrix and the SiC particle. We investigated the changes in interfacial product of the composites and mechanical properties such as interfacial bonding strength, and tensile strength in terms of the oxidized layer thickness of the reinforcement.

The mechanical properties of thin film materials are known to be different from those of bulk materials, which are generally overlooked in practice. The difference in mechanical properties can be misleading in the estimation of residual stress states in micro-gas sensors with multi-layer structures during manufacturing and in service.

In this study the residual stress of each film layer in a micro-gas sensor was measured according to the five difference sets of film stacking structure used for the sensor. The Pt thin film layer was found to have the highest tensile residual stress, which may affect the reliability of the micro-gas sensor. For the Pt layer the changes in residual stress were measured as a function of processing variables and thermal cycling.

Two- and three-layer composite models were developed using a beam vibration theory, and the models were applied for measuring Young's moduli of thin metallic films. The Cr, Ni, and Co-coated Si wafer composites (two-layer composite) and (Cr/Ti/Si) composites (three-layer composite) were produced by radio-frequency (rf) magnetron sputtering and used to test the developed models. Young's moduli of (Cr) films obtained by the three-layer composite model agree well with those of (Cr) films obtained by the two-layer composite model, considering (Ti/Si) as the one layer and (Cr) as the other layer. This suggests that moduli of multilayer films may be obtained by using a two-layer composite model repeatedly.

The mechanical properties and oxidation resistance of HIPed Ti5Si3 have been measured. HIPing submicron size powder compacts produces a crack-free, fine-grained microstructure with significantly higher hardness and toughness than a coarse-grained microstructure which contains microcracks within larger grains. Oxidation resistance is influenced by the grain size. Coarse-grained material has much lower mass gain than finegrained material in an oxidizing atmosphere and exhibits parabolic oxidation kinetics. The oxidation resistance of fine-grained material was measured between 700°C and 1000°C in air. Mass gain at 120 hours was measured to be 0.07 mg/cm2 at 700°C. At 900°C cracking of the scale leads to linear oxidation kinetics and significantly higher mass gain.