Characterizations of micromachined devices using planar motion analyzer (PMA)

In this paper we illustrate the capabilities of the planar motion analyzer (PMA) with a study of the dynamic and static behavior of a micromachined structure. Both static and dynamic characterizations and measurement settings are also demonstrated. The optical measurement system uses the laser vibration measurement technique for imaging; and then measuring the lateral resonant frequency and sensor displacements as well. The PMA analyzes in-plane vibrations of a MEMS device under a clear microscope. Its working principle is based on the stroboscopic principle. Based on this principle, characterization results in both time and frequency domains can be accurately generated and analyzed. Our device example for the measurement is a tunneling-based microresonator, which was fabricated using the backside released SOI (BARS) process. The lateral moving proof mass is suspended by the folded springs, and its tip protrudes to an opposing electrode by means of electrostatic forces