石英音叉扫描探针显微镜

Scanning Probe Microscopy Using Quartz Tuning Fork

石英音叉是一种谐振频率稳定、品质因数高的时基器件,其音叉臂的谐振参数(谐振振幅和谐振频率)对微力极其敏感。利用石英音叉对外力的敏感性,与钨探针结合,构成一种新型的表面形貌扫描测头。该测头与xyz压电工作台结合,利用测头音叉臂谐振频率对扫描微力的敏感性,研制基于相位反馈控制的扫描探针显微镜。首先介绍石英音叉测头的构成、工作原理和特性测试,以及由该测头构建的扫描探针显微镜的结构和测试、分析。通过对测头和系统的测试结果分析,系统达到1.2 nm的垂直分辨率,并通过对一维栅的测量,给出扫描获得的试样表面微观形貌图以及相位图,证明系统的有效性。另外,由于采用大长径比的钨探针,该系统具有测量大深宽比微器件表面轮廓的能力。

Quartz tuning fork is a time base device with stable harmonic resonance frequency and high Q-factor.The resonant parameters of tuning fork arm（resonance amplitude and resonance frequency） are sensitive to the micro force.Based on the sensitivity of the micro-fork to external force and combining with a tungsten tip,a new scanning probe for surface micro-topography measurement is fabricated.Co-operating with xyz piezo-electrical scanner and using the sensitivity of resonant probe to the scanning micro force,a scanning probe microscopy based on phase feedback control is developed.The structure,operating mechanism and performance test of the probe are given,and then the structure,test and analysis of the scanning probe microscope are described.Through the analysis of the test results of the probe and system,the system has a vertical resolution of 1.2 nm.Besides,an one-dimensional measurement optical grating is measured by the scanning probe microscope,and the surface topography and its phase map of the sample are obtained.The results show that the new scanning probe microscope operates effectively.In addition,because of using large aspect ratio of the tungsten tip,the system has the capacity of measuring micro structure with large aspect ratio.