Selective X‐ray analysis of electron localizing sites using capacitance or electrostatic force

Abstract

SUMMARYFor selective analyses of nanostructures, an X-ray analysis in which X-ray-induced photoionization of electron localizing sites is probed with capacitance (C) or electrostatic force (EF) is proposed. The photoionization of nanostructures with localized electrons provides a quasistable state with a long lifetime of 1 ms or longer. The photoionization is rapidly relaxed to initial state within several femtoseconds at the other sites without localized electrons. Because of high sensitivity of C and EF to the quasi-stable state with long lifetime, selective analyses of nanostructure can be achieved. We demonstrate this technique with samples of Cu metal and chemically deposited Si oxide film. We observe the modulation of C and EF with a parallel-plate capacitor and electrostatic force microscopy. The C modulation dependent on X-ray photon energy indicated an electronic state of Cu/Cu 2 O interface, and the EF modulation realized stoichiometry mapping of thin SiO x film on Si wafer.