Abstract
This study has successfully demonstrated a DRIE assisted wet anisotropic bulk micromachining (DAWN process) to fabricate various three-dimensional MEMS devices on the (100) silicon wafer and SOI wafer. This platform employs the characteristics of the DRIE process to prevent the convex corner undercut and crystal plane dependent effect during bulk etching. Moreover, these mesas and cavities with arbitrary shape can further integrate with suspended thin film structures and the structure formed by the inclined {111} crystal planes. This study has also developed various out-of-plane springs and actuators on SOI wafer using the SOI DAWN process. Further, the integration of these out-of-plane components with the existing in-plane components is also demonstrated. Thus, various multi-degrees-of-freedom (DOF) movable platforms made of single-crystal-silicon (SCS) are implemented on a SOI wafer. A novel method has been developed for the manufacture of a three dimensional multi-electrode array. The microneedle array can be employed for not only bio-neural stimulating but also in-situ signal recording, and a test on rabbit retina was also available. This study has also demonstrated the idea of concreting the aligned CNT-films using the chemical vapor deposited (CVD) polymer film, so as to form the “CNT-polymer” composite-film. The mechanical properties of the aligned CNT-film and the “CNT-polymer” composite-film are characterized. Thus the “CNT-polymer” composite-film could be a potential material for MEMS.