Construction of an ultra-low temperature scanning tunneling microscope

We describe designs and specifications of an ultra-low temperature scanning tunneling microscope developed at University of Tsukuba. It works over a wide temperature range between 90 mK and 300 K with atomic resolution as well as the capability of site specific tunneling spectroscopy. The microscope is now being used to study superconductivity and charge density waves in materials at millikelvin temperatures.