Application of Auger Depth Profiling on the AlSiO2 Interface

Abstract

Careful application of Auger depth profiling (ADP) in connection with quantitative consideration of electron escape depth and surface roughness allows to obtain a large depth resolution (0.5 nm at 10 nm film thickness) and a reduction of chemical changes due to the measurement. The Al‐SiO2 interlayer is very thin (about five atom layers) and may be described well with a simple penetration‐reaction model. The reduction of SiO2 and formation of Al2O3 can be caused by X‐rays, electron beam, or ion beam.

Detection of trap activation by ionizing radiation in SiO2 by spatially localized cathodoluminescence spectroscopy

“…Indeed, quantitative Auger-electron spectroscopy depth profile studies show that the Al-SiO 2 interface contains an interfacial layer due to reduction of the SiO 2 and formation of Al 2 O 3 . 28 This metal-semiconductor reaction is thermodynamically favorable, even at room temperature. 29 Such reactions are common at metal-semiconductor junctions in general, and their presence correlates with changes in interface charge transfer.…”

“…29 Such reactions are common at metal-semiconductor junctions in general, and their presence correlates with changes in interface charge transfer. 30 Bond breaking due to x-ray irradiation can promote the Al-SiO 2 reaction further 28 and could account for the increase in O vacancy defects and hence the R(2.7 eV/1.9 eV) increase at Location A after irradiation. While such bond breaking might also promote O diffusion from SiO 2 into Si, the thermodynamic driving force to form an Al oxide at the Al-SiO 2 interface is much higher.…”