石英音叉扫描探针显微镜

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。     

表面轮廓测定用扫描探针测头研究

利用压电聚偏氟乙烯(PVDF, Polyvinilidene fluoride)薄膜和压电微音叉(Micro-fork),分别与钨探针结合,构成了三种新型的表面轮廓扫描测头。该新型测头与x-y压电工作台结合,采用与TM-AFM（Tapping mode atomic force microscope）相同的工作原理,构成了扫描探针显微镜。分别介绍了这些测头的构成及特点,给出了所构成测量系统所获得的试验结果,证明了这几种新型扫描测头的有效性。     

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。     

基于聚偏氟乙烯的扫描探针显微镜系统

采用聚偏氟乙烯(PVDF)压电薄膜和压电陶瓷(PZT),并结合由电化学研磨得到的钨探针,研制了一种具有对称结构的新型轻敲模式扫描测头。在该测头中,PVDF压电薄膜作为振动梁,其下方中间位置固定有钨探针,在PZT的驱动下,PVDF和探针处于谐振振动状态,同时,PVDF作为微力传感器检测探针顶端原子与试样表面原子间的作用力。所构建测头结合三维纳米定位台、控制程序等构成了新型扫描探针显微镜系统。介绍了测头的构成、工作原理、特性以及SPM系统的整体结构、测量原理、三维工作台的定位控制、信号处理过程和整系统特性测试,并以一维标准光栅为试样进行三维图像扫描,证明了该新型扫描探针显微镜系统的可行性和有效性。     

基于PVDF扫描测头的电路系统构建及性能测试

一种采用PVDF薄膜和压电传感器结合钨探针构成的新型扫描测头可以对柔软易损坏及具有大台阶特征的表面实现高精度非破坏性测量.基于该新型测头构建了硬件电路系统,并通过相关试验测试了系统特性.试验结果证明:该扫描测头在垂直方向上可实现亚纳米级的分辨率.     

基于聚偏氟乙烯（PVDF）薄膜的新型SPM测头结构及性能研究

为了对柔软易损坏材料以及具有大台阶特征的表面实现高精度非破坏性测量,研制了一种采用PVDF薄膜和压电驱动器（PZT-actuator）结合钨探针构成的新型SPM测头。介绍了测头的构成和工作原理,并通过一系列相关实验,确定了测头的相关参数和性能（如薄膜的尺寸参数、所构成振动梁的品质因素及弹性常数等）,初步证实了该测头可以满足上述测量要求。     

扫描探针显微镜在粗糙度、纳米尺寸、表面形貌观测方面的应用

扫描探针显微镜是近十几年来在表面特征表面形貌观测方面最重大的进展之一，是纳米测量学的基本工具，本文叙述了扫描探针显微镜的工作原理、检测模式及在观察检测纳米级的粗糙度、微小尺寸、表面形貌方面的特点和方法，比较了原子力显微镜、常规的表面轮廓仪、干涉显微镜、扫描电子显微镜在表面特性、表面形貌观测方面的性能，着重介绍了扫描探针显微镜在这方面的应用和存在的问题。     

扫描力显微镜中的点衍射干涉现象及其应用

本文论述了扫描力显微镜中的点衍射干涉现象,论证了硅微探针可以作为后向点衍射板并用于检测微探针变位的光学原理。根据这一原理设计了一种新型灵巧的扫描力显微镜,它具有更好的抗干扰能力,稳定优质的光电信号。理论分析及实测表明,该扫描力显微镜具有０．０１ｍｍ 的纵向分辩率、５ｎｍ 左右的横向分辨率。     

坐标测量机高精度测头技术

介绍了坐标测量机高精度测头的研究发展现状;分析了接触方式,光学方式,扫描方式测头的优缺点,研究了日本松下公司研制的高精度测头测量原理;基于原子力微探针的基本原理,设计了一种新型的坐标测量机测头,指出了采用原子力准接触技术是测头向高精度发展的方向之一。     

实现变温扫描的扫描探针显微镜的发展与应用

将实现微尺度温度测量的技术按其温度控制方式分为两类,即控制探针的温度和控制样品的温度,所对应的仪器为扫描热显微镜和各类可直接应用于普通扫描探针显微镜的变温样品台,分别介绍其结构、工作原理及应用情况,分析了这两类具有不同控温方式的仪器的区别,并进一步讨论了目前在扫描探针显微镜变温辅助设备中仍然存在的问题以及实现变温扫描的扫描探针显微镜的发展前景.     

A long-stroke 3D contact scanning probe for micro/nano coordinate measuring machine

This paper presents a long-stroke contact scanning probe with high precision and low stiffness for micro/nano coordinate measuring machines (micro/nano CMMs). The displacements of the probe tip in 3D are detected by two plane mirrors supported by an elastic mechanism, which is comprised of a tungsten stylus, a floating plate and two orthogonal Z-shaped leaf springs fixed to the outer case. A Michelson interferometer is used to detect the vertical displacement of the mirror mounted on the center of the floating plate. An autocollimator based two dimensional angle sensor is used to detect the tilt of the other plane mirror located at the end of the arm of the floating plate. The stiffness and the dynamic properties are investigated by simulation. The optimal structural parameters of the probe are obtained based on the force-motion model and the constrained conditions of stiffness, measurement range and horizontal size. The results of the performance tests show that the probe has a contact force gradient within 0.5 mN/μm, a measuring range of (±20 μm), (±20 μm), and 20 μm, respectively, in X, Y and Z directions, and a measurement standard deviation of 30 nm. The feasibility of the probe has preliminarily been verified by testing the curved surface of a convex lens.     

Soft control of scanning probe microscope with high flexibility

Most commercial scanning probe microscopes have multiple embedded digital microprocessors and utilize complex software for system control, which is not easily obtained or modified by researchers wishing to perform novel and special applications. In this paper, we present a simple and flexible control solution that just depends on software running on a single-processor personal computer with real-time Linux operating system to carry out all the control tasks including negative feedback, tip moving, data processing and user interface. In this way, we fully exploit the potential of a personal computer in calculating and programming, enabling us to manipulate the scanning probe as required without any special digital control circuits and related technical know-how. This solution has been successfully applied to a homemade ultrahigh vacuum scanning tunneling microscope and a multiprobe scanning tunneling microscope.     

A versatile multipurpose scanning probe microscope

A combined scanning probe microscope has been developed that allows simultaneous operation as a non‐contact/tapping mode atomic force microscope, a scattering near‐field optical microscope, and a scanning tunnelling microscope on conductive samples. The instrument is based on a commercial optical microscope. It operates with etched tungsten tips and exploits a tuning fork detection system for tip/sample distance control. The system has been tested on a p‐doped silicon substrate with aluminium depositions, being able to discriminate the two materials by the electrical and optical images with a lateral resolution of 130 nm.     

基于电化学研磨的SPM钨探针制备方法研究

钨探针是扫描隧道显微镜(STM)常用探针之一。为了将钨探针应用于扫描探针显微镜(SPM)，根据钨探针的受力，通过理论分析确定了钨探针的理想轮廓：钨探针的直径变化应具有指数曲线。为了获得指数曲线轮廓、尖锐测头等良好特性的钨探针，分别提出并研究了改进的钨探针液面直流电化学研磨法和薄膜直流电化学研磨法。通过这两种电化学研磨法获得的探针以及通过传统的交流电化学研磨法获得的钨探针，分别在探针的形状、探针尖端曲率半径、表面质量、研磨速度、可复现性等多个方面进行了观察和比较。通过实验发现，除了研磨速度外，改进的液面直流电化学研磨法和薄膜直流电化学研磨法在其他各方面都优于交流电化学研磨法。     

Analysis of the contact probe mechanism for micro-coordinate measuring machines

High precision contact scanning probes for measuring miniature components on micro- and nano-coordinate measuring machines requires sensitive mechanisms. This paper analyzes the mechanism of a developed contact probe in order to find its optimal dimensions. The contact probe is composed of a fiber stylus with a ball tip, a mechanism with a wire-suspended floating plate, and focus sensors. The wires experience elastic deformation when a contact force is applied. The probe mechanism with a four-wire floating plate is studied. Stiffness analysis is carried out using the theory of elasticity. It is found that, with a proper stylus length, a contact probe with uniform stiffness can be designed.     

The art of electrochemical etching for preparing tungsten probes with controllable tip profile and characteristic parameters

Using custom made experimental apparatus, the art of electrochemical etching was systematically studied for fabricating micro/nano tungsten probes with controllable tip profiles of exponential, conical, multidiameter, and calabashlike shapes. The characteristic parameters of probe including length, aspect ratio, and tip apex radius could also be well defined. By combining of static and dynamic etching, the conical-shape probe with length up to several millimeters, controllable tip apex radius, and cone angle could be fabricated. In addition, by continuously lifting the tungsten wire up during the electrochemical etching with different speeds and distances, the multidiameter shape probe could be fabricated. Finally by controlling the anodic flow, the multiple "neck-in" could be realized creating a calabashlike probe. The aspect ratio of probes depends on (i) the effective contact time between the surrounding electrolyte and the wire, (ii) the neck-in position of immersed tungsten wire. Under the optimized etching parameters, tungsten probes with a controllable aspect ratio from 20:1 to 450:1, apex radius less than 20 nm, and cone angle smaller than 3° could be achieved. The technique is well suited for the tungsten probe fabrication with a stabilized stylus contour, ultra-sharp apex radius, and high production reproducibility. The art for preparing microprobes will facilitate the application of such microprobes in diverse fields such as dip-pen nanolithography, scanning probe microscopy, micromachining, and biological cellular studies.     

Probe design optimization for a high-resolution scattering-type scanning near-field optical microscope

The scattering-type scanning near-field optical microscope (SNOM) has a probe with a sharp tip for use in high resolution imaging. As sharp a tip as possible is generally considered ideal for the observations, but actually, a sharp tip does not always provide a high resolution SNOM image. We numerically examined the scattering property of the SNOM probe by the three dimensional finite difference time domain method. In this paper, we show the criterion for the ideal scattering probe which satisfies the simple relation between radius and taper angle of the tip.