DEVELOPMENT IN AUGER DEPTH PROFILING TECHNIQUE

The usage of Auger depth profiling technique in its conventional form was limited considerably by surface roughening accompanying the ion sp uttering. The depth resolution thus decreased with the thickness of th e removed layer. Introducing rotation of the specimen and using glanci ng-incidence-angle ions the surface roughening was greatly reduced. Ap plying these conditions, one can study the ion mixing effect, which is another limiting factor for the depth resolution. A Mo 3.6 - Si 3.3 n m multilayer system deposited on a Si substrate has been studied by AE S depth profiling with specimen rotation and glancing-incidence-angle ions (87-degrees to the surface normal) in the 1-2 keV electron and 1- 5 keV ion energy ranges, using a special ion gun. Depth profiling was followed by plasmon loss and elastic peak electron spectroscopy (EPES) . EPES enables variation of the sampling depth, while the AES sampling depth was approximately 0.4 nm. Plasmon loss spectra have been record ed on the Mo and Si layers and are considerably different from those o btained on pure Mo and Si, respectively. Simulation of the elastic pea k intensity versus profiling depth resulted in good agreement with exp erimental data. The calculation was based on a single elastic scatteri ng approach and with Liau's ion mixing model.