A SOI-MEMS-Based Single Axis Active Probe for Cellular Force Sensing and Cell Manipulation

Abstract

This paper presents the design, analysis, fabrication, and characterization of an electrostatically driven single axis active probing device for cellular force sensing and cell manipulation applications. The active probe is actuated by linear comb driver to create the motion in the probing direction. Both actuation and sensing comb drives are designed for the probing stage. The sensing comb structures enable us to sense the probe displacement when it is actuated, which enables application of force balanced sensing. The designed active probing device has an overall size of 5 mm × 4.5 mm, is fabricated on a silicon-on-insulator (SOI) substrate through surface micromachining technologies and deep reactive-ion etching (DRIE) process. The probe stage structure is fabricated on the 10-μm-thick device layer of SOI wafer. The handle layer beneath probe stage is etched away by DRIE process to decrease the film damping between the stage and the handle wafer thus achieving high quality factor. The proposed single axis probe is aimed at sensing cellular force which ranges from pN to μN and cell manipulation applications.