HIGH-PRECISION MECHANICAL APPROACH MECHANISM FOR A LOW-TEMPERATURE SCANNING TUNNELING MICROSCOPE

A novel mechanical micropositioner has been developed for producing ex act linear displacements in the nm range. Incorporated in a low temper ature scanning tunneling microscope (STM), it is used as a coarse appr oach mechanism for the tunneling tip. The advantage of the design is t he high accuracy of the linear motion and the absence of backlash. The design principle is discussed and its positioning accuracy and stabil ity for STM imaging are demonstrated. (C) 1997 American Institute of P hysics.