USE OF ZR- SECONDARY-ION ENERGY-DISTRIBUTIONS AND FACTOR-ANALYSIS TO CONSTRUCT CHEMICAL-STATE DEPTH PROFILES IN SIMS

Factor analysis (FA), the multivariate statistical technique, has been used to extract chemical bonding information from SIMS secondary ion energy distributions. The method is outlined in detail and shown to be capable of constructing quantitative profiles for the chemical states of zirconium present in ZrO2/Zr and ZrNx/Zr structures. In addition, a truncated data collection procedure wherein secondary ion intensity values are collected at a fixed number of emission energy values durin g the depth profile is outlined. This method, which enables data to be collected in a shorter time and from a smaller sample volume, is subs equently shown to yield reliable results, as confirmed by FA of Auger depth profiles on similar specimens.