A modulation technique for discrimination against ion induced auger electrons in micro‐area AES

Beam brightness modulation Auger spectrometry is shown to be an effective means of eliminating ion induced Auger electrons from Auger electron energy spectra. Modulating the incident electron beam intensity causes the true electron induced Auger electron emission to be modulated at the beam modulation frequency which can be easily separated from the unmodulated ion induced Auger electrons by means of frequency sensitive detection using a lock-in amplifier. This technique is particularly useful when depth profiling with a high energy ion beam (∼5 kV) and a low current (small spot) electron beam (<100 nA).