微波腔体微扰法在测厚技术中的应用

Application of the Method of Microwave Cavity Perturbation in Measuring Thickness Techniques

本文介绍一种微波腔体微扰法测量介质薄膜厚度的仪器。它的主要特点是:用圆柱TE_(011)模谐振腔作为介质膜厚度测量的传感器,将非电量厚度的参量转换为谐振的频偏值,用电调谐的场效应压控振荡器(FET-VCO)作为微波源。它们与指示电路组合构成测厚装置显示介质膜厚度。其结构简单,测量快速方便,可实现非接触测量,不受静电干扰,对ε'_r=2.0～3.0的塑料薄膜、分辨率优于032μm。

This article presents a thickness measuring meter for the dielectric films based on cavity perturbation. A high Q TE_(011) cylinderical cavity is used as the sensor, it transforms the thickness parameter into frequency-shift data. A FET voltage-control oscillator is used as the source.in conncction with a detective circuit to indicate the thickness of dielectric films. The device has some good features such as, simple structure, convenient for use,contactless measurement and without electrostatic interference.