Design of a compact scanning tunnelling microscope with a feedback to coarse approach controller for low scan ranges

Abstract

We describe here the design of a simple and compact scanning tunnelling microscope based on the principle of an inertial slider mechanism. The Z feedback which adjusts the tip–sample gap separation is applied to the coarse movement piezo unlike the conventional method of applying it to the four quadrants of the tip scanning piezo. This method produces better stability in addition to eliminating the requirement of four high voltage amplifiers. Several simple features incorporated in the sample stage improve the stability and reliability considerably.