用于扫描近场光学显微镜的一种新型非光学样品-探针间距测控方法

A novel non optical method of tip sample distance regulation based on shear force in scanning near field optical microscopy

扫描近场光学显微镜ＳＮＯＭ（ｓｃａｎｎｉｎｇｎｅａｒ－ｆｉｅｌｄｏｐｔｉｃａｌｍｉｃｒｏｓｃｏｐｅ）自八十年代中期以来获得了迅速的发展，并具有超衍射极限光学分辨率。作为ＳＮＯＭ的关键技术之一，样品与探针间距的控制十分重要而且实现起来比较困难。基于剪切力原理，本文提出了一种新型的样品－针尖间距测控的非光学方法，即，利用压电陶瓷的压电和逆压电效应，将压电陶瓷片分为三部分，分别用于激励探针振动、固定探针以及探测针尖振动变化。该方法的灵敏度很高，可将样品－针尖的间距控制在３ｎｍ左右，而且廉价、制备十分简单。

SNOM has been developed rapidly since the middle of 1980's and optical images with nano metric resolution have been obtained. As one of key techniques, sample tip distance regulaton is important and difficult to realize as well. By full use of piezoelectricity and the contrary effects of ceramic piezo electric element, half of a round PZT plate is divided into three parts and the different part is used as the stimulate dithering of fiber tip, fix and detect element respectively. A novel method for sample tip distance regulation based on shear force principle is presentd. It is very sensitive and the sample tip distance can be regulated below 3nm. In addition, it is very cheap and easy to prepare.