Microfabrication of hybrid structure composed of rigid silicon and flexible polyimide membranes

Abstract

We have designed and microfabricated millimeter-scale wing-shaped hybrid microstructures composed of rigid structures of single crystal silicon (SCS) and flexible polyimide (PI) membranes. The wing-shaped microstructures mimicking insect flapping flight have been designed using a fluid-structure interaction analysis, and have been microfabricated using microfabrication technologies with the SCS substrates coated with photosensitive polyimide membranes. The shape of the SCS parts of the hybrid microstructures have been fabricated using deep reactive ion etching (D-RIE) process. The flexible parts of PI membranes have been prepared using photolithography and the subsequent curing process of the micro-patterned photosensitive PI thin film. The wing-shaped hybrid microstructures fabricated have been observed, and the flexibility of the PI membrane part of the hybrid microstructures was also confirmed using the bending test of the PI membrane.