Exhibition Preview丨The 1st HAXPES Hard X-ray Photoelectron Spectroscopy Symposium

The first HAXPES Hard X-ray Photoelectron Spectroscopy Symposium will be held at Shanghai Zhangjiang Science City-Shanghai Light Source on October 12-13, 2024.

X-ray photoelectron spectroscopy (XPS) is a non-destructive detection technology that can achieve qualitative and quantitative analysis of elemental composition and chemical state on the surface of samples, and has been widely used in scientific research and industry. Traditional XPS uses soft X-rays as the light source, and its analysis depth is generally within 10 nm of the surface, while the depth analysis involving the bulk phase needs to be carried out with the help of ion beam etching. However, XPS depth analysis based on ion etching is a sample destruction process, which may cause the destruction of the chemical state and produce false images, so it is urgent to develop non-destructive depth analysis methods. For this reason, hard X-ray photoelectron spectroscopy (HAXPES) came into being. It uses higher energy hard X-rays (5-10 KeV) as the excitation source. The photoelectrons excited have a larger inelastic mean free path, so HAXPES can extend the detection depth of XPS to tens of nanometers. The unique advantage of HAXPES is that it can not only realize non-destructive in-depth analysis of interface structures, but also extend the detection information to deeper core energy levels. Therefore, HAXPES will provide strong support for basic scientific research and related industrial development.

HAXPES has been widely used internationally, such as non-destructive detection of metal oxide interface layers in semiconductor devices and in-situ analysis of electronic structures of solid-liquid interfaces. Important progress has been made. However, the basic research and applied research based on HAXPES in China are still in the initial stage, especially the HAXPES facilities based on synchrotron radiation light sources are still relatively lacking. The Energy Materials Line (E-line) of Shanghai Light Source is the first composite line station in China that covers the soft and hard X-ray energy range. The photon energy range is 130-18000 eV. It is an ideal platform for basic and applied research on HAXPES, and has developed ultra-wide energy range near-ambient pressure XPS and HAXPES methods. At the same time, X-ray sources based on Cr targets (Kα, 5.42 KeV) and Ga targets (Kα, 9.25 KeV) have also been successfully applied to laboratory HAXPES instruments.