Fabrication and Characterization of a MEMS Thermal Convective Accelerometer on Silicon-in-Glass Substrate

In this article, the fabrication and characterization of a 2-D micro-electromechanical system (MEMS) thermal convective accelerometer are demonstrated. This sensor consists of a heater and four thermistors. The central heater warms up the chip to a temperature higher than the ambient, while the four thermistors, which are arranged symmetrically around the heater, monitor the temperature gradients induced by the acceleration. The heater and thermistors are fabricated on one side of a silicon-in-glass (SIG) substrate using a glass reflow process. The utilization of this SIG substrate not only enhances the sensor robustness at low power consumption but also allows the lead wires of the sensor to be directly soldered to the printed circuit board (PCB), significantly simplifying the sensor packaging. Experimental tests on the fabricated accelerometer indicate that the sensor can measure acceleration exceeding 80 m/ $\text{s}^{{2}}$ , with an approximate linear sensitivity of about 150 mV/g. The proposal of this SIG-based device provides a new paradigm for developing high-reliability and low-power-consumption MEMS accelerometers.