Polyimide sacrificial layer for an all-dry post-process surface micromachining module

In this paper we present a novel post-process surface micromachining module that uses a commercial PI2610 polyimide as a sacrificial layer and PECVD SiC or SiN as structural layers. No wet etching is required thus avoiding stiction problems often encountered in wet sacrificial etching processes. A mask set containing cantilever beams, membranes, rotating structures, microswitches, etc. is applied to evaluate the potential of this process module. Silicon carbide micro-mechanical switches with different beam size are also designed and prepared using the three-mask process module suitable for appending to a CMOS fabrication sequence. A displacement /spl ges/15 /spl mu/m is achieved for 95 V and 235 V for the 1 /spl mu/m and 2 /spl mu/m wide silicon carbide beam, respectively.