X-ray Photoelectron Spectroscopy Depth Profiling of La2O3/Si Thin Films Deposited by Reactive Magnetron Sputtering

The La2O3/Si thin films have been deposited by reactive DC magnetron sputtering. Amorphous state of La2O3 layer has been shown by RHEED observation. Top surface chemistry of the a-La2O3 has been evaluated with layer-by-layer depth profiling by ion bombardment and XPS measurements. It was found by core level spectroscopy that the top surface of the a-La2O3 film consists of hydrocarbon admixture, lanthanum carbonate, and hydroxides that formed as a result of contact with air atmosphere. Thickness of this top surface modified layer is below 1 nm for a contact time of similar to 1.5 h with air at normal conditions.