Takao Adachi

The optimized SMA micro pump chip applicable to liquids and gases

We fabricated a high performance micro pump chip with optimized design. This chip can flow not only liquids but also gases (12 µ/min., 25 kPa for water. 11 µ/min., 5 kPa for air). Moreover, the micro pump is tolerant of gas bubbles in the liquid chamber and it is possible to prime itself. To achieve this performance, the micro pump improved three elements. The first one is eliminating pressure loss of the check valves. The second one is optimizing flow pattern inside the deformable chamber. And the third one is increasing compression ratio of the deformable chamber. Our original 3D micro fabrication process named “Hybrid IH process (micro stereo lithography)” to hybridize various micro parts (silicone rubbers, SMA actuators etc.) with UV-polymer structure was utilized for chip fabrication. Therefore, their packaging without leakage was made successfully.

Microstereolithography and its application to biochemical IC chip

The worlds first micro stereo lithography, named IH process, was proposed and developed by the speaker in 1992. By now, several types of micro stereo lithography systems have been developed. Three-dimensional resolution of solidification has reached to 0.2 micron at present. These 3D micro fabrication processes using UV curable polymer gave a big impact on not only MEMS but also optics. The latest version of IH process enables us to make a movable micro mechanism without assemble process or sacrificial layer technique often used in silicon process. It is well known that the IH process is the mother of two-photon micro stereo lithography and its applications. Recently new micro chemical device named Biochemical IC Chip was proposed and developed by the speaker. This chip is based on the module IC chip-set like todays TTL family. IH process enable to make the biochemical IC including real three-dimensional micro fluid channels. Various kinds of Biochemical IC chips such as micro pump, switching valve, reactor, concentrator and detector have already been fabricated successfully. Basic performance of micro chemical devices constructed by the biochemical IC chips were demonstrated. The biochemical IC chips will open new bioscience and medicine based on innovative technology.

Multi-Micro PuMP Chip to Flow Gases and Liquids

We fabricated the optimized SMA micro pump chip applicable to both liquids and gases. The measured maximum flow and pressure for water were 12 µl/min. and 25 kPa, respectively. And the flow and pressure for air were 11 µl/min. and 5 kPa, respectively. Moreover, the micro pump satisfied insensitive ability to gas bubbles and self-priming. This performance was realized by improving the check valves, the chamber and the SMA actuator design. Our original 3D micro fabrication process named “Hybrid IH process (micro stereo lithography)” to hybridize various micro solid parts with UV-polymer structure was utilized for chip fabrication. Therefore, their packaging without leakage was made successfully.