【作者】 李梦超；

【导师】 胡小唐；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2007， 博士

【摘要】 扫描隧道显微镜(STM)是纳米测量研究中最有利的工具之一,提高仪器精度和重复性是测试的两个重要的指标。STM工作时隧道间隙在几个纳米左右,即使在使用隔振平台的情况下,在测量过程中也会受到外界随机振动的影响,且测量的重复性很低。因此,振动已经成为提高纳米测量精度的主要障碍之一。抗振、隔振、振动补偿技术成为纳米测量领域中的一大分支,特别是纳米级振动测试技术的发展,对于纳米学科的研究具有非常重要的意义。振动对STM的测量结果影响很大,说明STM对振动非常敏感,反过来思考,利用基于隧道效应的测量原理,可以对纳米级振动进行检测,并对STM振动引起的误差进行补偿。本课题的研究内容主要包括:1.对纳米级振动测量机理和方法进行初步的研究和探索,提出基于隧道效应的纳米级振动检测的方法。该方法可以实现STM工作状态下进行在线的检测,而且采用和STM相同的测量原理,可以实现对STM的全补偿。2.设计了采用双平台微动结构的纳米级振动检测实验系统,两个平台分别在横向和纵向达到纳米级的分辨率。这样可以保证在隧道状态下对纳米级振动进行测量。系统具有稳定,刚性好,符合阿贝误差原理设计的特性。3.设计了适用于隧道电流测量的检测电路。设计了测头结构,解决了检测电路屏蔽和针尖固定的问题。进行了隧道电流的静态、动态特性的测量试验,并对静态特性进行了标定,其分辨率可以达到1pA。4.利用该实验系统进行了纳米级振动的检测实验,得到不同频率、不同振幅、不同激振信号情况下,系统对纳米级振动的响应情况。实验表明,系统对频率、振幅等改变情况下,其输出响应也会出现规律性的改变。5.分析了该实验系统误差的来源,提出后续需要改进和解决的方法,为纳米级振动微型传感器的设计打下基础。更多还原

【Abstract】 Scanning tunneling microscopy is one of the advantageous instruments for nano measurement study, instrument precision and repetition are two important indexes. Even if using the vibration-isolation platform, it is easily affected by the outer random vibration in the course of measurement and the measuring repetition is not well, because the tunneling gap only has several nanometers or less. The vibration has become one of the obstacles to improve the nano measurement precision. Now, the anti-vibration, vibration isolation, vibration compensation are one branch in the nano measurement field, especially it has great important significance in the nano subject, especially along with the development of the nano test technology.The vibration has great influence on the measuring result of STM, considering inversely, STM is very sensitive to the vibration in the measurement. Using this measuring principle, the nano level vibration can be detected and compensated for the error of STM by vibration.The main research works are listed as follows:1. The principle of nano level vibration detection is studied primitively and the method of nano level vibration detection based on the tunneling effect is put forward. This method is fit for online detection in STM working state and it can realize the complete compensation because the same measuring principle.2. The nano level vibration detection system using the double micro-motion stage is designed, two stage have nano level resolution in the horizontal and vertical direction respectively. Using this system, it can ensure the measurement of nano level vibration. The system is stable and rigid, and it accords with Abbe error design principle.3. The detection circuit suitable for the measurement of tunneling current is designed. According to the character of the detection circuit, the measuring head is designed to solve the circuit shield problem and the tip fixing. The measuring experiments of the static and dynamic character of tunneling current are carried out and the static character is calibrated. The resolution of the circuit is 1pA.4. The detection experiments of nano level vibration are made and the response of the system to the nano level vibration is available in the different frequency, different amplitude and different signal. The experiments show the output response also has regular change under changeable frequency and amplitude.5. The source of the system error is analyzed and the improved and settling method is put forward. All of this will make a foundation for the design of micro sensor for nano level vibration.更多还原