Ultra precise 2-dimensional atomic tracking control for atom craft

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In this research, for the promote of the nanotechnology, we propose a compact absolute length measuring machine (ALMM) with sub-nanometer accuracy and sub-millimeter travel by combining crystalline lattice and the phase modulation homodyne laser interferometry. With the ALMM, an arbitrary length can be determined by combining fine scale (= lattice spacing) and coarse scale (= wavelength). The following results were obtained with the aid.(1) Ultra precise /stable laser interferometer system ; We developed a phase modulation homodyne laser interferometer with multi-path configuration, which can determine length incase optical path difference equals to products of wavelength and integer. A positioning control system for the stage using the interferometer, a fast DSP and precise AD/DA was also developed.(2) High stiff STM and ultra precise sample stage; A high stiff STM and a precise stage with the range of 10 micrometer and the resonance frequency is over 2kHz was developed using a flexture springs. It is easy to detect atomic image of graphite (HOPG) by combining the two instruments.(3) Direct measurement of lattice spacing on HOPG surface ; By comparing the atomic STM image of HOPG with the displacement of the sample stage, the lattice spacing on the HOPG surface was determined with high accuracy.(4) Protype of ALMM; We developed the protype of the ALMM, which included the phase modulation interferometer, dual sample stages, high stiff AFM/STM heads, thermo-stabilized vacuum cell. The performance has been evaluated.