In this paper, we propose the method that PZT thin layer, which is formed on a Si substrate, can be transferred to polydimethylsiloxane (PDMS) without additional chemical contamination. In consideration of embedding in the substrate more easily, sandwich structures of PZT between two metal layers are used as thin-film capacitor. To embed PZT in the PDMS substrate by dry process, 3-mercaptopropyltrimethoxysilane (MPTMS) is used in this process as the molecular glue. MPTMS was coated on the upper electrode, gold, as an adhesive layer between gold and PDMS. As a result, the sample with thickness of 300 nm that was treated with MPTMS is embedded in PDMS.

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The silica agglomerates were formed on PFA film by the application of colloidal silica followed by drying to prepared the silica-agglomerates electret. Three methods, inkjet-printing, air-spray and ultrasonic nebulization, were used to apply the colloidal silica on the film. The prepared electrets were heated on a hot plate to investigate the heat resistance. The silica-agglomerates electret showed higher charge retention than the PFA electret over 200℃. The electret on which silica agglomerates were formed by inkjet-printing or air-spray indicated that the charge retention was monotonically increased with the area fraction of silica agglomerates. Furthermore, the prepared electrets were kept under humidity of 60 to 70% to investigate the humidity resistance. The charge retention of the electret n which silica agglomerates were formed by inkjet-printing was not changed while it was gradually decreased when silica agglomerates were formed by ultrasonic nebulization. These results suggested that the application of silica agglomerates was effective method to enhance heat resistance of fluorine resin film.

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Delamination damages in a juncture between different materials will raise problems in electric products, such as semiconductor plastic package. In this study, we are proposing a tactic to achieve robust juncture between leadframe and epoxy resin based on nano-structure control of leadframe surface. In the result, nano-structure of plated layer on leadframe can be controlled by a strict condition of electroplating bath. The nano-structure controlled leadframe surface shown remarkable robust junction to the epoxy resin successfully.

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We developed a twin-probe atomic force micrsocpy (AFM) system using Si-cantilever probes. The system utilizes the optical beam deflection method for detecting the deflection of each cantilever-probe mounted on each tube-type actuator. The cantilever-probes mounted on each actuator are realized independent control of the probe positions, which are attached to manual-sliders. Each displacement sensing sensitivity of two cantilever-probes achieves 90fm/√Hz or less. We succeeded the simultaneous observation of the topographic image under the state which they approached mutually with 40µm.

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This paper reports a novel method of evaluating the actual Bn (Brownian Noise) in capacitive sensors for high sensitivity. By analyzing the frequency response of the electrical impedance, the proposed method provides an advantage of evaluating the Bn associated with the mechanical characteristics of capacitive sensors even when the sensors are packaged. We employed the method to measure the quality factors of the MEMS capacitive sensors, and evaluated the value of the Bn and the damping coefficients. The experimental results show a good agreement with the conventionally-known physical parameters.

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