This paper presents a touch mode MEMS capacitance diaphragm gauge for differential pressure measurement. The design principle of the gauge is demonstrated, then the diaphragm deflection and capacitance sensitivity are analyzed theoretically. Experimental work was carried out using a principle prototype, which has a square pressure-sensing diaphragm with large width-to-thickness ratio. The test results are consistent with the theoretical model for pressure from 1 Pa to 1000 Pa, and the capacitance-pressure curve of the gauge is near linear in three pressure sections and a maximum sensitivity of 135 fF/Pa is achieved in low pressure range. Moreover, high pressure test results ranging from 1000 Pa to atmospheric pressure indicate that the developed touch mode gauge has wide load range and good overload protection.

本文提出了一种用于差压测量的触摸模式MEMS电容膜片计。阐述了液位计的设计原理，然后从理论上分析了膜片的挠度和电容灵敏度。实验工作是使用一个原理原型进行的，该原型具有一个方形的压力感应膜片，该膜片的宽厚比大。测试结果与从1 Pa到1000 Pa的压力的理论模型一致，并且压力表的电容-压力曲线在三个压力部分中接近线性，并且在低压范围内获得了135 fF / Pa的最大灵敏度。此外，从1000 Pa到大气压的高压测试结果表明，开发的触摸模式压力表具有宽负载范围和良好的过载保护。