Information depth determination for hard X‐ray photoelectron spectroscopy up to 15 keV photoelectron kinetic energy

In the present work, we have determined the information depth in a solid for hard X‐ray photoelectron spectroscopy (HAXPES) up to a photoelectron kinetic energy of 15 keV. For that, we have followed the evolution of the photoemission signal from different core levels of a gold overlayer grown in situ on a polycrystalline copper substrate as a function of the photoelectron kinetic energy. We demonstrate that in the case of gold, an information depth of 57 nm can be achieved by detecting photoelectrons with 15‐keV kinetic energy. The photoemission signal produced at this depth corresponds to 0.2% of the signal coming from a semi‐infinite solid bulk. Such a high sensitivity can only be reached with the combination of a third‐generation synchrotron radiation beam with a high‐transmission electron analyzer. Copyright © 2008 John Wiley & Sons, Ltd.