Abstract
By direct comparison it is shown that Auger electron spectroscopy (AES) is more sensitive than appearance potential spectroscopy (APS) for the detection of S, C, and O on a Ti film. Similar combined studies of a number of clean films reveal that APS is about equally sensitive to Cr, Ti, Fe, and Ni, but is unable to detect Cu, Ag, or GaAs under the present conditions. The sensitivity of AES to all these materials in bulk form is the same within a factor of 5.