From stainless steel 'til atomic ordeal. Creating a research ready STM

Abstract

Scanning Tunneling Microscopy (STM) is a technique with which the surfaces of metals, semiconductors and superconductors are investigated. A bias voltage is applied between the atomically sharp tip of the microscope and the surface of the sample. Through the tunneling of electrons between the tip and sample a constant current is established and the surface of the sample can be investigated. When using a new scanning tunneling microscope small vibrations can disrupt the delicate experiments. Sources of these vibrations can be external, such as pumps, or internal, such as vibrations leaking in from the computer. In this thesis we show how these vibrations can be investigated and reduced to 0.2pm peak to peak in order to make the microscope fully operational. Electrical wires, vibrations from the building and pumps have been found to be sources of these vibrations causing noise in the measurements. After reducing these vibrations it was shown that benchmark experiments could be conduc- ted. These experiments include scanning tunneling spectroscopy, taking atomic resolution images and atomic manipulation. By comparing the results of the experiments to literature it can be confirmed that the results match and therefore results of upcoming research can be trusted.