Use of Cluster Secondary Ions for Minimization of Matrix Effects in the SIMS Depth Profiling of La/B4C Multilayer Nanostructures

The elemental composition of La/B4C multilayer metal structures is studied using SIMS on a TOF.SIMS-5 experimental setup. Analysis conditions that make it possible to considerably enhance the depth resolution are found. They include using low-energy O-2(+) and Cs+ ions for sputtering and cluster secondary ions for registering matrix elements. The roughness evolution in the etching crater region is studied in a layer-by-layer analysis. It is shown that, at an incidence angle of 45 for sputtering ions, the rms roughness increases slightly (from an initial value of 0.5-0.7 nm) in the etching crater of the (La/B4C)(70)/Si structure at a depth of 0.5 mu m. The profiles of elements in multilayer structures grown using two different types of magnetron systems with stationary and high-frequency discharges are compared. The main contaminations in the structures are determined.