Observation of Energy-filtered Images and Energy Dispersive Images of Au/Ta Photoelectron by EXPEEM with a Wien Filter Type Energy Analyzer

Review of Scientific Instruments

Yoshikawa

Kimura

et al. 2006

We have newly developed an x-ray photoemission electron microscope (XPEEM) which uses both soft x-rays and hard x-rays at the undulator beam line BL15XU in the synchrotron radiation (SR) facility SPring-8 to observe various practical materials. In combination with an energy analyzer and high brilliant x-ray source, the detection of high kinetic energy inner-shell photoelectrons is essential for revealing the chemical properties of specimen subsurfaces or buried interfaces, owing to long inelastic mean free path of the high kinetic energy photoelectrons. The most significant result in our design is the new combined electric and magnetic field objective lens in which the magnetic field penetrates up to the sample surface. This allows the measurement with high spatial resolution of both low intensity images of inner-shell photoelectrons with high kinetic energy and high intensity images of secondary electrons. By using the sample bias scan method, we can easily change the focus condition of the objective lens in order to allow the energy filtered imaging with photoelectrons having the kinetic energy in a wide range (1–10000eV). By the combination of high brilliant SR x-rays, the new objective lens, and sample bias method, our XPEEM can successfully obtain the microarea x-ray photoelectron spectra and energy filtered XPEEM images of inner-shell photoelectrons, such as Si 1s, without any surface cleaning procedure. The energy filtered XPEEM image using photoelectrons from deep inner shells, Si 1s, was obtained for the first time.

Section: B Energy Dispersion Spectral Images and Energy Filtered Imagesmentioning

confidence: 99%

On the wide-energy-range tuning of x-ray photoemission electron microscope optics for the observation of the photoelectrons excited by several keV x-rays

Review of Scientific Instruments

Yoshikawa

Kimura

et al. 2006

Application of x‐ray photoemission electron microscopy developed at SPring‐8 BL15XU

Surface & Interface Analysis

Yoshikawa

Kimura

et al. 2004

We have been developing x-ray photoemission electron microscopy (XPEEM) designed for measurement with both soft x-rays and hard x-rays at SPring-8 beamline BL15XU, in order to realize two-dimensional chemical analysis and to establish a technique for the micro-area x-ray absorption fine structure (XAFS) for practical materials. In this work, surface images of SbTe amorphous/crystalline patterned film, used as the recording layer for the digital versatile disc -rewritable (DVD + RW), were observed by XPEEM. We have also demonstrated the micro-area x-ray absorption near-edge structure (XANES) of Sb L III spectra in a 200 × 200 nm 2 area by means of XPEEM, and successfully distinguished the spectrum of the amorphous bit region from that of the crystalline region.

Observation of Element-Specific Energy-Filtered X-Ray Photoemission Electron Microscopy Images of Au on Ta Using a Wien Filter Type Energy Analyzer

Ohminami

Tsutsumi

et al. 2004

Jpn. J. Appl. Phys.

We estimate how well we will know the parameters of solar neutrino oscillations after KamLAND and Borexino. The expected error on ∆m 2 is few per-mille in the VO and QVO regions, few per-cent in the LMA region, and around 10% in the LOW region. The expected error on sin 2 2θ is around 5%. KamLAND and Borexino will tell unambiguously which specific new measurement, dedicated to pp solar neutrinos, is able to contribute to the determination of θ and perhaps of ∆m 2 . The present data suggest as more likely outcomes: no measurement, or the total pp rate, or its day/night variation.