Thermoforming of Parylene C to Form Helical Structures

Microfabricated, thin film, Parylene C helices down to a 0.25 mm diameter were achieved using a post-fabrication thermoforming process. This overcomes the planar configuration imposed by MEMS fabrication techniques. By utilizing a thermoplastic, Parylene C backbone, planar devices can be fixtured into a desired 3D geometry and thermoformed, permanently transforming the device into the fixtured shape. This work characterizes the thermoforming process and necessary parameters to achieve 0.25 to 2.6 mm diameter helices in bare Parylene strips and microfabricated Parylene and metal devices without insulation (Parylene) or electrical (metal) failure.