Production and Demonstration of Atomically Clean Metal Surfaces

Abstract

Ion bombardment as a means of cleaning solid surfaces has been tested by applying it to the metal tungsten. The test, which showed the resulting surface to be clean, is a sensitive one because atomically clean tungsten is very reactive to the common gases. The test is definitive since it is performed on a material for which there is overwhelming evidence that another means, namely heating, does produce an atomically clean surface. The phenomenon used in this work to observe surface conditions during the cleaning procedures is the Auger-type ejection of electrons by slowly moving positive ions. This is again shown to be a sensitive means of detecting surface contamination. Data on the electron release by ions from heavily contaminated metal surfaces are reported.