Quantitative analysis of buried interfacial impurity layers by SIMS and RBS

In order to test the quantitative accuracy of secondary ion mass spectrometry (SIMS) analysis of interfacial layers using ion-implanted standards, we have compared SIMS and Rutherford backscattering (RBS) analyses of buried silver layers (about 10¹⁵ Ag/cm²) at silicon-silicon thin film interfaces. The silver interface concentration was determined by RBS on a system whose calibration was checked using a bismuth implant standard. At the same time, measurements were made on a set of silver-implanted samples. These implants were subsequently used as secondary standards in the SIMS analyses of the silver interfacial layers. The results of the independent analyses indicate that SIMS analyses at interfaces can be performed with a relative accuracy bettet than 15% and with detection limits on the order of 10^-3 monolayer.