Laboratory Hard X-ray Photoelectron Spectroscopy

Hard X-ray photoelectron spectroscopy (HAXPES) has recently attracted attention for its unique capabilities. High energy X-ray enables to excite deep core level electrons and in parallel the information depth from the sample surface is significantly larger than conventional XPS, which enables to investigate electronic structures beneath the sample surface and buried interface without destructive ion etching. Although most of the previous HAXPES studies have been conducted with synchrotron radiation source, laboratory HAXPES is getting more and more attracted in practical applications. In this review, we report unique capabilities of the laboratory HAXPES with our recent applications, which has both of soft and hard X-ray as excitation sources.