Ultra precise 2-dimensional atomic tracking control for atom craft

由于超精密工程，如纳米技术，迅速发展，需要一种新的定位方法与亚纳米分辨率。如果晶体没有应力，则对于一些规则晶格的约0.2nm的晶格间距在长范围内是均匀和稳定的。扫描隧道显微镜（STM）具有高性能以获得晶体表面的原子图像。因此，通过将晶体与STM相结合，这种晶体晶格可以用作具有亚纳米分辨率的定位基准。我们提出了一个原子跟踪控制的STM针尖参考原子顶点和阵列上的晶体表面。在本研究中，我们发展了一种原子追踪控制的稳定化方法，以对抗外界的干扰。使用该基金取得了以下成果。(1)研制了一种超精密直线运动工作台。直线度为0.2角秒，谐振频率为2kHz， ...更多信息 10微米的nning范围分别进行了评价。使用该平台和STM头可以很容易地获得原子图像。(2)分析了STM隧道电流对外界干扰的噪声，将其分为空气中的噪声、STM针尖与样品之间的热漂移噪声和来自地面的振动噪声三部分。部分（C）可以通过提高STM仪器的刚度和通过使用防振台来去除。部分（A）的振幅和频率分别相对较小和较高。然而，部分（B）的幅度变化和频率分别相对较大和较慢。(3)采用两级PI控制器实现了原子跟踪控制的稳定性。每一级PI控制器分别对扰动（A）或（B）进行补偿，然后将它们合并。两级PI控制器对扰动（A）和（B）都有很好的补偿效果。少

Since ultra precision engineering, e.g. nanotechnology, has progressed rapidly, a new positioning method with sub-nanometer resolution is required. The lattice spacing of approximately 0.2 nm for some regular crystalline lattice is uniform and stable over a long range, if the crystal is stress free. The scanning tunneling microscope (STM) has high performance to obtain an atomic image of a crystalline surface. Therefore, such crystelline lattice can be used as a positioning reference with sub-nanometer resolution by combining the crystal and a STM. We have proposed an atomic tracking control of the STM tip by referring atomic apex points and arrays on crystalline surface. In this research, a stabilization method for the atomic tracking control against the outer disturbances has been developed. The following results were obtained using the fund.(1) An ultra precise stage with fine straight motion was developed. The straightness of 0.2 arc second, the resonance frequency of 2 kHz and sca … More nning range of 10 micrometer were evaluated, respectively. An atomic image was obtained easily using the stage and a STM head.(2) The noises on the tunneling current of the STM against the outer disturbances were analyzed and divided into the following three parts; (A) the sound noise in air, (B) the thermal drift between the STM tip and the sample and (C) the vibration noise from the floor. The part (C) can be removed by enhancement of the stiffness of the STM instrument and by use of the anti-vibration table. The amplitude and frequency for the part (A) were relatively small and high, respectively. However, the amplitude change and frequency for the part (B) were relatively large and slow, respectively.(3) The two-stages PI controller was implemented for the stabilization of the atomic tracking control. Each stage PI controller was adjusted for compensation of the disturbance (A) or (B), respectively, and then they were combined with. Both the disturbance (A) and (B) were compensated well with the two-stage PI controller. Less