Hard x-ray photoemission spectroscopy

Hard x-ray photoemission spectroscopy (HX-PES) has been realized using high-energy and high-brilliant synchrotron radiation at SPring-8. High energy (∼6-keV) excitation results in larger probing depth of photoelectrons compared to conventional PES, and enables a study of intrinsic electronic property of materials much less influenced by surface condition. With this newly realized technique, requirements for surface preparation are much reduced, if not eliminated. The high energy resolution and high throughput was confirmed by measuring Au 4f core level and valence band spectra. It is a non-destructive tool to determine electronic structure from surface to genuine bulk as shown by a study on SiO2/Si(100). Electronic structure modification related to the ferromagnetism in the diluted magnetic semiconductor Ga0.96Mn0.04N was observed. (author)