Fabrication of high-aspect-ratio polymer-based electrostatic comb drives using the hot embossing technique

We report on the formation of a lateral comb drive on poly-methyl-meth-acrylate (PMMA) using the hot embossing technique. A hot embossing mold insert is fabricated on a silicon wafer by means of lithography and inductive coupled plasma dry etching. The comb drive microstructure is hot embossed under a molding force of 35000 N at 130°C. We demonstrate the comb drive, 80 units of interdigitated parallel capacitors with the finger gap and width both being 10 μm. The minimum feature size is 5 μm and the thickness of the structure is 60 μm, which makes the aspect ratio 12:1. The comb drive strokes 5 μm under an actuation potential of 180 V. We also present a brief description of the design and simulation with ANSYS.