A Novel Two-Dimensional Micromachined Accelerometer Based on Thermocapillary Heat Transfer

In this work, we demonstrate the first prototype of a thermal-bubble-based two-dimensional (2-D) micromachined accelerometer. The only moving element in this accelerometer is a thermal-bubble created by vaporizing the working liquid contained in the chamber. The accelerometer consists mainly of a heating resistor and two pairs of temperature detectors placed symmetrically and orthogonally. The prototype devices indicated that a sensitivity of 1.5degC/g for an operating power of 60 mW can be realized. The frequency response of the accelerometer containing DI water is measured to be 200 Hz, and the corresponding noise equivalent acceleration (NEA) is approximately 1 mg/Hz^1/2.