低温环境下MEMS动态测试系统

研制了低温环境下MEMS动态特性测试系统.对低温环境的产生及其关键问题、低温环境下的激励方法、信号检测方法,及高速数据采集方法进行了初步研究.采用半导体冷阱产生低温环境,为防止低温下结霜对测试精度造成影响,测试在真空环境中进行.研制了基于压电陶瓷的底座激励装置,用于低温环境下对微器件激励.采用2种方法用于低温环境下微器件振动响应信号的检测,一种是采用内置敏感元件的方法,被测微器件受到激励后自身输出信号,经高速数据采集单元采集进入计算机;另一种是采用激光多普勒测振仪在低温环境外部进行检测.以LabVIEW为平台开发了测试系统控制软件,实现了微器件激励、数据采集、存储自动化.对系统的总体设计、硬件组成、系统功能、实验研究等方面作出了详细阐述.

Dynamic test system for MEMS in low temperature environment

A dynamic test system for MEMS in the environment of low temperature was developed. The issues of low temperature environment generation, micro device excitation in low temperature environment, response sig-nal detection and high speed data acquisition are discussed. A thermoelectric cooling refrigerator is utilized as the low temperature environment; to prevent the influence of frost on test precision in low temperature environment,dynamic test is carried out in vacuum environment. An excitation device used in low temperature environment is developed, which adopts a piezoelectric ceramic as the driving source. Two schemes are adopted to realize the measurement and acquisition of the oscillation signal of the micro structure in low temperature: one is the built-in sensor method, with which the micro structure outputs signal by itself when it is excited and the signal is acquired into a computer through a high speed data acquisition unit; another one uses a laser-Doppler vibrometer to meas-ure the signal outside the low temperature environment. The test control system software is written based on Lab-VIEW, and the automation of the excitation, data acquisition and storage is realized. This article elaborates the system design, hardware and software composition and experiment result in details.