Study on fabrication process of micro-bridge structure arrays based on amorphous silicon films

The critical technology for fabrication of the micro-bridge structure based on amorphous silicon (a-Si) films is studied. As a key technology in the fabrication of the micro-bridge structure, the sacrificial layer technology, including the preparation of polyimide thin films (i.e., curing, wet etching, and plasma etching processes), is systematically researched, and a series of key parameters are obtained. An improved process flow of self-supporting micro-bridge structure is established. Experimental results and scanning electron microscope (SEM) images show that the fabrication technology presented is simple and feasible. A 160×120 micro-bridge array is successfully fabricated using this method. © 2010 Chinese Optics Letters.