Papers by Author: Kenta Suzuki

Abstract: Flexible micropumps are important components for advanced microfluidic systems. Here, polyimide (PI) for flexible micropumps was focused on. This is because PI has many advantageous properties such as good biocompatibility, high thermal stability, and superior mechanical strength. However, the difficulty in realizing an all-PI micropump lies in fabricating microstructures on PI film surfaces. In this paper, we present improved performances of a flexible all-PI micropump fabricated using high-temperature hot embossing above 320 oC that is considerably higher than its glass transition temperature of 275 oC. The fabricated micropump had diffuser/nozzle valves and a chamber with 5 mm diameter, and it was functioned by vibrating a 2-µm-thick PI diaphragm with alternating air pressures outside of the diaphragm. The flow rate of deionized water in the micropump reached to 110 μl/min at 3 Hz.

Abstract: A ring-shaped low-frequency resonator operating in the in-plane (2,1) mode was designed and fabricated utilizing anodic bonding of a 9-µm-thick single-crystal silicon to a glass substrate. Although the gap between the ring and the driving electrode was relatively large (900 nm), a high quality factor of 4212 at 1.609 MHz was realized. The motional resistance was 1.853 MW. In addition, the resonant frequency was electrically tuned by varying the dc bias of drive electrodes with 21.5 ppm/V. Therefore, it was expected that this resonator could possibly replace low frequency quarts resonators of a few MHz ranges.