Development of a novel MEMS gas flowmeter with a temperature difference suspension structure

Abstract
Micro-electro-mechanical systems (MEMS) gas flowmeters are innovative devices that use microfabrication technology to measure gas flow with high precision and sensitivity. With MEMS technology, flow measurement can now be performed more accurately and compactly than ever before, using low-power, compact, and highly accurate sensors. MEMS gas flowmeters utilize various principles to measure gas flow, including thermal, Coriolis, and pressure differential methods.A micro flowmeter was designed using a MEMS sensor and a weak signal acquisition technique. The MEMS sensor used a thermal resistor-suspended VO2 structure to provide high heat isolation and sensitivity. Since SU-8 gum was used for the flow channel, the technology was simple and affordable, making it suitable for batch production.
To acquire high-resolution, low-noise data, the following device used a super low bias current operational amplifier, aided by Guard ring protection, and a 24-bit high-resolution ADC. The sensor and data acquisition combination shows that the flow meter has favorable linearity and sensitivity between 0 and 50 mL/min at a specific offset voltage. The flow meter should have advantages such as high sensitivity and stability, low cost, and so on, to satisfy the applications in the fields of biochemical detection and medicine.