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Resonant Auger spectra of H2O are recorded with unprecedented resolution, for excitation energies tuned across the O 1s→2b2 resonance. Electron emission spectra for decay to the 1b2-1 final state show a partially resolved vibrational envelope whose overall appearance is photon energy dependent. Comparison with ab initio calculations indicates that the two-dimensional nuclear motion of the Auger final state can be controlled by sampling different portions of the potential curve and changing the nuclear motion in the core-excited state.

We report on the selective-area growth and characterization of wurtzite (WZ) InP/AlGaP core–multishell nanowires. Quantum well (QW) structures were fabricated in AlGaP multishells by changing the alloy composition. Transmission electron microscopy revealed that the AlGaP multishells were grown with a WZ structure on the side of the WZ InP core. The lattice constants of the WZ InP core and WZ AlGaP shell were determined by X-ray diffraction. Cathodoluminescence studies showed that the WZ AlGaP QW with an Al composition of 20% exhibited green emissions at 2.37 eV. These results open the possibility of fabricating green light-emitting diodes using WZ AlGaP-based materials.

The valence- and conduction-band electronic densities of states (DOSs) in amorphous (a-) GeSe and GeTe were investigated by means of ultraviolet photoemission and inverse-photoemission spectroscopy (UPS and IPES), respectively. The UPS spectra for both a-GeSe and a-GeTe are very similar to those obtained in previous experiments; a distinct peak appears near the top of the valence band. The IPES spectra for both a-GeSe and a-GeTe corrected by subtracting the background exclude the possibility of a structure with 3(Ge):3(chalcogen) coordination if one compares them with the theoretical DOS calculated by O'Reilly, Robertson and Kelly. The corrected IPES spectrum for a-GeSe resembles the broadened theoretical DOS for chemically ordered 4(Ge):2(Se) structure, whereas that for a-GeTe resembles the theoretical DOS for randomly bonded 4(Ge):2(Te) structure. The characters of the conduction-band DOSs for a-GeSe and a-GeTe were also examined by means of soft-x-ray core absorption spectroscopy. The Ge and Se core absorption spectra of a-GeSe are very similar to those of a-, and were discussed using a simple bonding model with a 4(Ge):2(Se) local configuration. The Ge and Te core absorption spectra of a-GeTe were also discussed using a simple local bonding model. All of the present measurements indicate that both a-GeSe and a-GeTe have structures with 4(Ge):2(chalcogen) coordination.

We grew AlInP on two types of GaN substrate in order to transfer the wurtzite (WZ) structure to grown layers. An AlInP epitaxial layer grown on GaN with high-density stacking faults was obtained. X-ray diffraction and Raman scattering analyses indicate that the dominant crystal structure of the AlInP layer grown on GaN was WZ. Cathode luminescence measurements at 35 K revealed strong green emissions from the WZ AlInP layer, suggesting an energy band gap change from indirect to direct. These results demonstrate the potential of WZ AlInP as a new candidate for high-efficiency green emission material.

Soft X-ray absorption spectra of the lowest excited triplet states of several organic molecules (quinones, benzaldehydes, and other carbonyls) and potential curves of valence- and core- doubly excited states are calculated for the O 1s region.

Both anisotropic ablation and thin film formation of polytetrafluoroethylene (PTFE) were successfully demonstrated using synchrotron radiation (SR) irradiation of PTFE, that is, the SR ablation process. Anisotropic ablation by the SR irradiation was performed at an extremely high rate of 3500 µm/min at a PTFE target temperature of 200° C. Moreover, a PTFE thin film was formed at a high rate of 2.6 µm/min using SR ablation of PTFE. The chemical structure of the deposited film was similar to that of the PTFE target as determined from Fourier transform infrared absorption spectroscopy (FT-IR) analysis.

X-ray absorption near edge structure (XANES) spectra of the Diluted Magnetic Semiconductors (DMS) system Zn1-x Mn x S have been measured at the Zn LII,III-edges and of Zn1-x Y x S (Y = Mn, Fe, Co) at the S K-edge using total electron yield mode. The Zn LIII-edge results for Zn1-x Mn x S reveal a dramatic reduction in intensity of the first prominent feature, just above the edge, in the XANES spectra. Analysis of the S K-edge XANES spectra for Zn1-x Y x S revealed an increase in a pre-edge peak and a corresponding decrease in the first above-edge peak with increase in transition metal content in the alloys. These results are consistent with more S 3p- transition metal (Y) 3d(t2) hybridized states and less S 3p- Zn 4(s,p) and S 3p-Zn 3d hybridized states becoming available as transition metal content increases in the alloys.

X-ray excited optical luminescence yield spectra of single crystals of pure NaBr and Cu-activated NaBr are reported. X-rays are scanned at the energy regions of K edges of Br and Na. The yield spectra for the intrinsic luminescence emission band of NaBr at 4.5 eV for both samples and those for the Cu impurity luminescence band at 3.4 eV are compared. The results show that in the NaBr:Cu, both positive and negative edge jumps are observed depending on the monitored emission band. The yield spectra are reproduced with the calculation following our recent phenomenological theory.

The photo-assisted etching of heavily phosphorous-doped polycrystalline silicon by chlorine was studied using synchrotron radiation as an extreme ultraviolet (EUV) light source. The quantum yield for the removal of the Si atoms at a chlorine pressure of 0.3 Torr was found to be about 0.5% photon-1 using the Ti-filtered light, which is mostly in the EUV region, 1-20 nm. Formation of electronically excited Cl+ ions upon EUV irradiation was confirmed by emission spectroscopy. Negative bias applied to the Si crystal was found to increase the etch rate.