Development of Fabrication Process for Large-Displacement Polymer MEMS with Stacked Movable Structures Based on Hot Embossing and Polishing

Abstract

This paper reports on our study of a fabrication process for polymer MEMS devices utilizing hot-embossing and polishing steps. In this paper, a PMMA thermal microactuator was developed and characterized to demonstrate the process's capability and robustness. In the hot-embossing step, a two-step silicon mold fabricated using bulk micromachining technology was used to create PMMA microstructures. Then, the hot-embossed structures were bonded to the PMMA substrate using a surface activation bonding method, and the back layer of the hot-embossed PMMA structure that remained after hot embossing was removed by a polishing step to release the movable microstructures. A V-shaped PMMA thermal microactuator with a thickness of about 50 孠was fabricated and tested successfully. The displacement was about 10 times larger than that of a Si counterpart at the same temperature difference.