Study on an efficient fabrication process for PMMA movable microstructures based on hot embossing and polishing processes

This paper reports our study on an efficient fabrication process for polymer microstructures utilizing hot embossing and polishing. In this paper, PMMA micro movable structures are set as the target. First, a silicon mold is fabricated by bulk micromachining technology. Next, PMMA microstructures are formed on PMMA plate by hot embossing process. Then, the hot-embossed structures are bonded to a PMMA substrate, and the backside layer of the hot-embossed PMMA structure that remained after hot embossing is removed by polishing to release the movable structures. PMMA movable microstructures with line and space of 10 µm and 5 µm, respectively, and the thickness of about 60 µm have been fabricated successfully. This is a low-cost and highly efficient method to fabricate polymer MEMS devices.