In this paper, we present a SPICE equivalent circuit model of an electrostatic vibration energy harvester. The SPICE model consists of a generation part and a mass-spring system part considering electrostatic force. The change in capacitance between electrodes with the position of the mass is analyzed by FEM analysis and is applied for the generation part. For investigating the characteristics of the actual harvester, the harvester was fabricated and charged by a -200 V monopolar potential. The maximum output power of the monopolar-charged harvester is 1.1 µW with applied vibration amplitude of 350 µm_pp at 323.3 Hz with 0.8 MΩ optimum load resistance. We confirmed that the examined and analyzed results indicate high correspondence.

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This paper reports a novel approach to modify a microfluidic chip by hybrid molding of small pieces to the inner wall of PDMS microchannel exposing the surface of the pieces. In this research, we employed a LSI chip and a microfabricated chip as an embedded piece. Addition of intermediate material between a piece to be embedded and a mold prevent a functional surface of the piece from possible coverage with PDMS. Agarose gel showed the best performance as such intermediate material. The use of the optimal amount of agarose successfully embedded a bare LSI chip as a functional piece into the inner wall of PDMS microchannel without wraparound or moat. This research enables us to fabricate microfluidic chips of complicated hybrid structure with various sensors as chip at low cost.

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To curtail manufacturing cost of PZT pyroelectric sensor device, we reduced ion milling and ashing process by the lift-off method Pt formation and CSD method PZT thin film deposition. Remanent polarization of the PZT film on patterned Pt was approximately 2P_r = 15 µC/cm². This value was 2/3 of all over coated Pt deposited at 600°C, but its pyroelectric current was 0.6 pA/mm². PZT on SiO₂/Si has cracks, but by splitting the SiO₂ face into 20 µm rectangular through patterning Pt, these cracks were reduced to 20%. Furthermore, ladder-formed Pt electrode was satisfactory for crack-free PZT film on SiO₂/Si.

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In this paper, we report the optimized combo sensor using quartz crystal resonator for analyzing the physicochemical properties of liquids. This sensor can measure the mechanical properties and the electrical properties simultaneously by integrating a LFE (Lateral Field Excited) sensor with an ACR (Antiparallel Coupled Resonator) or two types of ACR sensor on a same substrate. We optimized the electrode diameter of resonator for measuring a glucose aqueous solution or NaCl aqueous solution. Moreover, we measured concentration of glucose aqueous solution and NaCl aqueous solution with optimized sensor. This sensor is expected to be used for product quality control in industrial plants.

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In this study, we have fabricated a droplet manipulation device which has a microchannel oscillated by piezoelectric actuator. This device can manipulate droplets by producing a pressure distribution of a standing acoustic field caused by ultrasonic vibration in the microchannel. The manipulated droplet's size has been estimated from the relationship between acoustic force and viscous force. The device has been designed by using a finite element method analysis. Fabricated device has been evaluated by observing droplets in manipulation experiment and measuring a manipulated droplet's distribution. When n-dodecane was used as dispersed phase, this device can manipulate a droplet whose diameter is larger than 20µm when the applied voltage and the driving frequency were 80V_p-p and 2.25MHz. When Silicone oil was used as dispersed phase, the manipulated droplets diameter was larger than 15µm. From these results, we have indicated that the microchannel device can manipulate droplets by using ultrasonic vibration.

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The concept of unobtrusive physiological balance sensing system implementing biosensors is discussed. Biosensors connected with a data system is expected to play a significant role when we extend the sensing objects from body to mind and spirit. Here, we describe the unobtrusive monitoring system using FET-type sensors and wireless communication devices. Substances subject to the survey of our research will include small ions, immunoglobulins, and hormones.

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