Parylene-C Coating on High Resolution MEMS Tactile Sensor for Protection of Measurement Surface

In this paper, we report the effect of parylene-C coating on a high resolution 2-axis MEMS tactile sensor for protection of the contact surface of measured samples. Thin parylene-C layer was coated on overall device chip surface, and the improvement effect was evaluated to use it as a coating material suitable for protection of the measurement surface. The effect of parylene-C layer coating to mechanical characteristic of the tactile sensor was within 5%, even though 3μm-thick parylene-C is deposited on the suspension springs. Protection effect of the parylene-C layer was also evaluated with measured samples of color paint on a metal. As a result, the depth of scratches made by sensor sweeping motion was much reduced by 60%, and the sensitivity and the spatial resolution was almost not affected. Parylene-C is an effective material for coating of high resolution tactile sensor surface.