It is very difficult to obtained the Auger depth profile of InP multilayer structures with argon ion sputtering because the very large surface roughness is caused; therefore the analyses of InP multilayers have been carried out practically with the angle-lap profiling method. In order to establish an Auger depth profiling analysis method for a InP/GaInAsP multilayer structure specimen with the conventional depth profiling analysis method, we have investigated the dependence of the depth resolution on ion accelerating voltage and ion current density. The depth resolution improved according to the increasing the argon ion accelelating voltage in the range of 1-3keV. We have obtained the excellent Auger depth profile of the InP/GaInAsP multilayer structure by using the argon spot beam of high ion density.
Factors influencing the secondary ion yield and depth resolution in the SIMS depth profiling of carbon in the tantalum thin films have been investigated. The highest ion yield of C has been achieved with 193TaC- by using Cs+ primary ion beam. However some changes in surface topography during Cs+ ion sputtering were observed. We found that the extent of the changes differed depending on implanted C+ doses and that the depth resolution became lower as the quantity of dosed C increased. These phenomena are supposed to be due to that Ta crystals became amorphous and carbonized.
We have carried out the Auger depth profiling analysis of GaAs/AlAs multilayer structure using the peaks of GaMVV and A1LVV. Since the two peaks of the specimen overlapped each other, we made peak separation with peak synthesis technique using a non-negative least-square curve fit containing a peak-shift correction. The top-hat filtered spectra were used for the calculation to remove their background. This procedure gave excellent results for the peak separation especially for the sample which had a large difference in elemental concentration.