基于改进型DLIA的AFM探针高速振幅检测

发布时间：2018-05-20 12:33

本文选题：原子力显微镜(AFM) + 轻敲模式　；参考：《微纳电子技术》2014年12期

【摘要】：轻敲模式是原子力显微镜(AFM)最为常见的扫描模式之一。轻敲模式以探针振动信号幅值作为反馈信号,实行实时检测。目前,有模拟检测和数字检测两种检测方法,模拟检测方法由于模拟器件固有的温漂导致误差较大,数字检测方法误差小但运算量较大。提出了一种实时检测轻敲模式信号振幅的改进型数字锁相放大器(MDLIA),在自制的AFM扫描成像系统中同时具备误差较小和运算量较小两个优点。MDLIA使用与振动信号同频同相的方波信号作为参考信号,因此仅采用单通道运算即可检测振动信号幅值。首先通过理论分析介绍了MDLIA的原理,然后介绍各组成部分及实现过程,最后通过运算耗时实验验证MDLIA运算量小且运算速度快的特点,并通过误差对比实验证明MDLIA误差较小,同时通过标准栅格扫描实验验证MDLIA的稳定性。
[Abstract]:Tap mode is one of the most common scanning modes in AFM. In tap mode, the amplitude of probe vibration signal is used as feedback signal, and real-time detection is carried out. At present, there are two detection methods: analog detection and digital detection. The error of analog detection method is large due to the inherent temperature drift of analog device, and the error of digital detection method is small but the calculation is large. In this paper, an improved digital phase-locked amplifier for detecting the amplitude of tap mode signal in real time is proposed. In the self-made AFM scanning imaging system, it has two advantages: less error and less computation. MDLIA is used with the same frequency and same frequency as the vibration signal. The square wave signal of the phase is used as the reference signal, Therefore, the amplitude of vibration signal can be detected only by single channel operation. Firstly, the principle of MDLIA is introduced through theoretical analysis, then the components and the realization process are introduced. Finally, the characteristics of MDLIA are proved to be small and fast by time-consuming experiments, and the error comparison experiment proves that the error of MDLIA is small. At the same time, the stability of MDLIA is verified by standard grid scanning experiment.
【作者单位】：中国科学院沈阳自动化研究所机器人学国家重点实验室;中国科学院大学;
【基金】：国家自然科学基金资助项目(61304251) 国家高技术研究发展计划(863计划)资助项目(2012AA041204)
【分类号】：TH742

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