Photoelectron based soft x-ray detector for removing high order x rays

• Published in: Review of scientific instruments 2020-08, Vol.91 (8), p.083103-083103
• Main Authors: Nagasaka, Masanari, Iwayama, Hiroshi
• Format: Article
• Language: English
• Subjects: Photoelectrons; Polymer films; Scientific apparatus & instruments; Sensors; Silicon carbide; Soft x rays; Spectrum analysis; X ray absorption; X ray detectors; X-rays
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/5.0011302

Soft x-ray absorption spectroscopy (XAS) in the low energy region below 200 eV is important to investigate chemical and biological phenomena under an atmospheric condition since it covers K-edges of Li and B and L-edges of Si, P, S, and Cl. Monochromatic soft x rays usually include not only first order x rays but also high order x rays due to the high order diffraction of a plane grating monochromator. It is difficult to measure XAS in the low energy region under an atmospheric helium condition since the transmitted soft x rays mostly consist of the high order x rays due to the low transmission of the first order x rays. In this study, we have developed a photoelectron based soft x-ray (PBSX) detector, where the Au 4f photoelectrons emitted by the first order x rays are separated from those by the high order x rays using a difference in kinetic energies of photoelectrons. By using the PBSX detector, we have successfully obtained Si L-edge XAS spectra of the SiC and polymer/SiC films that mainly include the first order x rays by removing the major contributions of the second order x rays at the C K-edge and the fifth order x rays at the O K-edge. In the future, several physical, chemical, and biological phenomena in solution will be investigated by XAS in the low energy region with the PBSX detector.