Compact piezoelectric X-Y positioner on a sample holder of scanning tunneling microscope
作者单位：Department of Physics and AstronomySeoul National University
会议名称：《第18届国际真空大会》
会议日期：2010年
关 键 词：X-Y positioner STM
摘 要：Piezo-scanner used in STMs has limited the scanning range up to several micrometers in two dimensions. Various two dimensional positioners have been tried to cover wider scanning range of STMs in order to locate the probing tip over a position of interest. However, existing positioners require entire modification of the previous STM system. Changing the original STM system is difficult because one should redesign the whole STM head and resize other parts. We constructed a X-Y piezoelectric positioner that requires only minor modification of the original STM system. It is designed to move a sample holder over a distance of some millimeters with a few nanometer steps on a plane. It has one X-aligned shear piezo stack and another Y-aligned shear piezo stack being orthogonal to the former one and its size is about 20×20×10 mm. Slip-stick motion could be realized by a contact consists of a stainless steel ball and a polished alumina surface. This X-Y positioner could be made by modifying only the sample holder and the electrical connection part between the STM head and new sample holder. We could expand scanning range to a few millimeters without modifying original STM system. Because only a slightly modification was needed, it was possible to use the original sample holder. For uniform samples we could use the original sample holder and for patterned samples or samples which have nano-structures, we could use our modified sample holder. Our observations are performed using optical microscope in the air at room temperature. We expect further improvement can be done by adjusting tension between a stainless steel ball and a polished alumina surface or by changing the combination of contact materials.