A Cryogenic Quadraprobe Scanning Tunneling Microscope System with Fabrication Capability for Nano-transport Research

Abstract

We describe the development and the capabilities of a Quadraprobe system, consisting of a low temperature four-probe scanning tunneling microscope (STM) and a high resolution scanning electron microscope (SEM), coupled to a molecular-beam epitaxy sample preparation chamber. The four STM probes can be manipulated independently with sub-nanometer precision, enabling atomic resolution STM imaging and four-point electrical transport study of surface electronic systems and nanostructured materials at temperatures down to 10 K. Additionally, the four scanning probes with automated motion controls allow for atom assembly to perform "bottom-up" fabrication of nanostructures. Some testing results are presented.