Design and performance of a programmable-temperature scanning tunneling microscope

In this article we introduce a novel scanning tunneling microscope (STM), which operates in a sample temperature range from 60 to at least 850 K. The most important new feature of this STM is that, while one selected part of the surface is kept within the microscope's field of view, the sample temperature can be varied over a wide range of several hundreds of degrees during actual imaging. The extremely low drift of the scanner and sample was achieved by the combination of a thermal-drift compensated piezoelectric scanner design with a newly developed sample stage. The design of the sample stage defines a fixed center from which thermal expansions, in all three directions, are forced outwards. The performance of the microscope is demonstrated for several surfaces including Au(110), on which we follow one particular surface region over a temperature range of more than 270 K.