A VERTICAL HORIZONTAL 2-DIMENSIONAL PIEZOELECTRIC DRIVEN INERTIAL SLIDER MICROPOSITIONER FOR CRYOGENIC APPLICATIONS

We have developed a simple, two-dimensional piezoelectric tube device which uses the inertial slider method to achieve remote micropositioning in the vertical and horizontal directions. The motion of the slider car occurs with respect to a quartz rod which is attached to, and accelerated by the piezo tube. The vertical motion, against or with gravity, is achieved by activating the longitudinal mode of the piezo tube. The horizontal motion is a rotation about the quartz rod, achieved by activating the bending mode of the piezo tube. The device is very compact, works at cryogenic temperatures and is ultrahigh vacuum compatible. Step sizes from 10 to 3000 nm and speeds up to 0.2 mm/s are possible. A computer simulation model of the inertial slider process has been developed also, to investigate the effectiveness of various activating waveforms. It confirms the advantage of a cycloidal-like waveform recently reported in the literature. Also, the model predictions are consistent with the results obtained in the laboratory. A diagram of the analog circuit developed to produce a cycloidal-like waveform to drive the piezoelectric is included. We briefly describe an alternative design where the activating piezoelectric is attached to the slider car which moves vertically on a fixed quartz rod.