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In-situ observation of thermal stresses in thin films deposited on a silicon substrate was made by synchrotron radiation. Specimens prepared in this experiment were nano-size thin aluminum films with SiO₂ passivation. The thickness of the films was 10 nm, 20 nm and 50 nm. Synchrotron radiation revealed the diffraction intensities for these thin films and make possible to measure stresses in nano-size thin films. Residual stresses in the as-deposited state were tensile. Compressive stresses were developed in a heating cycle up to 300°C and tensile stresses were developed in a cooling cycle. The thermal stresses in the 50 nm film showed linear behavior in the first heating stage from room temperature to 250°C followed by no change in the stress at 300°C, however, linearly behaved in the second cycle. On the other hand, the thermal stresses in 20 nm and 10 nm films almost linearly behaved without any hysteresis in increasing and decreasing temperature cycles. The mechanism of thermal stress behavior in thin films can be explained by strengthening of the nano-size thin films due to inhibition of dislocation source and dislocation motion.

Novel processes for fabricating micro/nano sized oxide devices employing self-assembled monolayers (SAM) were developed. SAM of PTCS (phenyltrichlorosilane) was modified to have a phenyl / hydroxyl-group pattern by UV irradiation using a photomask and was used as a template to arrange inorganic fine particles. Surface modification of micro/nano sized inorganic particles and chemical reactions between those particles and SAM were studied. Two-dimensional arrangement of functional particles on a SAM in a controlled manner through the formation of strong chemical bonds, such as amide or ester bonds, can be applied to the future microelectronics and photonics.