The depth dependence of the depth resolution in composition–depth profiling with Auger Electron Spectroscopy

The depth dependence of the depth resolution in composition–depth profiles using Auger electron spectroscopy is briefly appraised to emphasize some of the different mechanisms operating for different classes of material and to show how the use of a characterized Ta 2 O 5 on Ta reference material can help to optimize the depth resolution. In addition it is shown that, even for flat uniformly‐layered samples sputtered under ideal conditions where the ion beam crater is flat and impurities may be ignored, five factors still limit the depth resolution: information depth, statistical effects and cascade mixing, electron stimulated desorption and sample roughening. These may each be observed to dominate at the appropriate depth for amorphous materials but, for evaporated polycrystalline metal films, the last term dominates for depths greater than 10 nm.