基于相位反馈控制的压电微音叉扫描探针显微镜

压电微音叉具有谐振频率稳定、品质因数高和易于实现音叉臂的振动检测等优点。利用微音叉的这些特性,将其与钨探针结合,构成了压电微音叉扫描探针显微镜(SPM)测头,可实现对微观表面的测量。该测头扫描时,压电微音叉的谐振频率被试样表面原子和钨探针尖端原子间的作用力调制。探针的谐振状态通过锁相环路(PLL)实现,微音叉测头与试样间的恒定测力及测头的Z向定位通过相位反馈控制实现。此外,测量系统可同时获得试样表面的微观轮廓图和相位图。

Scanning Probe Microscoply Using Piezo-elecltrical Micto-folk Based on Phase Feedback Control

Piezo-electrical micro-fork has many advantages such as stable resonant frequency,high Q-factor and its vibration is easy to be measured. Based on these advantages of the micro-fork and combining with tungsten tip,a scanning probe microscope（SPM） stylus was constituted and can scan the micro-surface. When the stylus scans the sample,the resonant frequency of the piezo-electrical micro-fork is modulated by the force between the atoms of the sample surface and the tungsten probe＇s tip. The resonant state of the micro-fork is kept stable by phase locked loop（PLL）. The constant scanning force and the localization of probe in Z direction are kept by the phase feedback control technique. Besides,the measuring system can obtain the profile and phase diagram of the sample＇s microstructure simultaneously.