Deep layers analysis by hard x-ray photoelectron spectroscopy

Hard X-ray photoelectron spectroscopy (HXPES) has developed to be used in wide ranges of solid state science and technology due to its much larger information depth comparing to the conventional X-ray photoelectron spectroscopy. It enabled to investigate buried layers as deep as more than 20 nm from the surface. Here in this article, various applications of HXPES to the deep layer investigations including chemical state prôling by takeoš angle dependence measurements and standing wave methods, intermixing analysis of metal multilayers, analysis of band bending at the semiconductor hetero interfaces, analysis of 2 dimensional carriers in strongly correlated materials interfaces, electronic structure observations at buried layers and their interfaces in devices. Laboratory HXPES system with monochromatic Cr Ka X-ray excitations is also introduced with its applications to Si MOS gate stack model samples including interface state spectroscopy by electric ̂eld application are also introduced.