Electrostatic-Capacitive MEMS Force Sensors: A State-of-the-Art Review

MEMS force sensors are used in a wide range of technical applications, spanning from industrial and biomedical to consumer and biological fields. Due to their widespread adoption in the market, significant efforts have been dedicated in researching and developing various transduction principles, sensing materials, and innovative mechanical designs. This review summarizes the most employed transduction principles for force sensing at the MEMS scale. Among these, electrostatic-capacitive MEMS force sensors are particularly well-suited for implementing closed-loop configurations, as they can integrate both capacitive sensing and electrostatic actuation within a single device thus keeping the system compact and favorably compatible with integrated circuit. Accordingly, this review focuses on the latest research in the literature on electrostatic-capacitive MEMS force sensors operating in both open-loop and closed-loop configurations. The working principles of both approaches are discussed, along with their respective advantages and disadvantages, and a comparison of state-of-the-art sensors in terms of resolution, sensitivity, and measurement range is provided. Finally, the review presents future perspectives, highlighting challenges and opportunities for MEMS force sensor development. The goal is to offer references that can aid in improving the design and performance of novel MEMS force sensors.[2025-0166]