There is increasing interest on solid-state biosensors due to potential advantages such as small size, low-cost, high density integration for point of care testing and next-generation drug discovery. In many cases, a gold electrode is used as a sensing surface on which specific biomolecule recognition events take place. However, gold is not always the best material for potentiometric measurement since the surface of gold electrode is polarized in aqueous solution, and there is room for improvement in stability of interface potential at the gold electrode surface. In this paper, we fabricated and characterized the mixed surface of self-assembled monolayer of alkanethiol and silver chloride to realize both stable interface potential and immobilization of biomolecules.

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The purpose of this article is to investigate the possibility to realize a fully integrated CMOS-Microfluidic device, the micro-fluidic channel being fabricated inside the CMOS chip, and passing underneath some micro-electrodes. The micro-channels are fabricated by isotropic deep-etching of silicon, which allows lateral etching, and then etching underneath the micro-electrodes. The electrodes are expected to be used for an all integrated system for electrical characterization of cells flowing underneath (flow impedance spectroscopy). This technology proposes an alternative to standard PDMS microfluidic channels which have limitations when applied to CMOS devices. Actually, these one have small size and have highly integrated pattern, making the alignment to the PDMS channel quite tricky. With the proposed technology, highly integrated device with micro-fluidics is obtainable, thanks to a submicron alignment precision. Moreover, it also gives possibilities of batch processing of integrated micro-fluidics on CMOS.

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Previously, we have developed a human monitoring system, which used 8051 microcontroller. The system has a 3-axis acceleration sensor, a pressure sensor, a humidity sensor, and an electrocardiogram (ECG) circuit. This paper reports the newly developed system by using PSoC (Programmable System-on-Chip), which is a microcontroller with some analog blocks in a single chip. The ECG and the acceleration are sampled at 125 Hz, the others are at 1 Hz by the PSoC. The sampled data are stored on the micro SD card or Static RAM (SRAM), transmitted by a Bluetooth module or USB interface to a PC. The multipurpose I/O pins for addition of some sensors are designed in the system. The multipurpose I/O pins are utilized to control and communicate with an infrared temperature sensor. The system was designed and fabricated by 4-layer printed circuit board (PCB). In comparison with the previous work, the system size was reduced from 85×48×15 mm³ to 50×50×15 mm³, the power consumption without Bluetooth communication was reduced from 45.0 mA to 24.6 mA when the power supply voltage is 3.3 V and the master clock is 48 MHz.

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This paper describes the design and experimental results of CMUTs (Capacitive Micromachined Ultrasonic Transducers) using an anodically bondable LTCC (Low Temperature Co-fired Ceramics) wafer. Electrical connection of the CMUTs top electrode and the LTCC via were successfully performed at a time of anodic bonding by forming Au bump on the electrode. The vibration characteristics of the membrane were measured by a laser Doppler vibrometer both in the atmosphere and in the water. Ultrasonic pressure signal of CMUTs arrays was measured using hydrophone.

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[in Japanese]

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