Robert Williams has pioneered the application of surface science techniques to the study of semiconducting solids and important interfaces in solid state electronic devices. He is accredited with developing the multi-technique approach to surface science within which the crystallography, chemical properties and electronic structure of semiconductors and associated metal overlayers are probed at the same time as their conventional electrical and optical properties.
More specifically, his novel experimental and theoretical work has resulted in a detailed understanding of compound semiconductor surfaces. His observations, showing how controlled intermediate layers of gas or metals can be used to modify metal–semiconductor interfaces, will be of lasting practical importance.
Robert was amongst the first to demonstrate that angle-resolved photoelectron spectroscopy could be used to determine the detailed electronic band structure of solids and also to appreciate the potential of synchrotron radiation as a probe for studying matter. His classic research, involving synchrotron radiation coupled with angle-integrated and angle-resolved photoelectron spectroscopy, played a vital role in the development of the Synchrotron Radiation Source at Daresbury.