Depth Profiling Analysis of InP/GaInAsP Multilayers by Auger Electron Spectroscopy. Effects of Zalar Rotation and Liquid Nitrogen Cold Stage

We have investigated the Auger depth profiling analysis of InP/GaInAsP multilayer specimens. It is difficult to obtain the Auger depth profile of InP sample by argon ion sputtering because it causes a great increase in surface roughness of the specimens. In order to reduce the roughness caused by the argon ion bombardment, the Zalar rotation method and sample cooling method were applied to the depth profile analysis of InP/GaInAsP specimens. The ion species used for sputtering was Ar+. Ar+ accelerating voltage was 1.0kV. The electron accelerating voltage was 5keV, the beam current was 0.1 μA and measured Auger lines were In-MNN, P-LVV, Ga-LMM and As-LMM. The Zalar rotation method gave good results in the depth profiling of In-MNN and P-LVV. The surface roughness was observed by SEM. On the other hand, the sample cooling liquid nitrogen temperature gave excellent analytical results the depth resolution was about 80Å at the depth of 4600Å. We found few cones on the sample surface after depth profiling analysis using the sample cooling method.