A description is given of several new applications of the NIST Database for the Simulation of Electron Spectra for Surface Analysis (SESSA). These applications include: (i) the determination of effective attenuation lengths for different XPS configurations, algorithms, and materials; (ii) examination of the effects of elastic scattering on film thicknesses obtained from the Tougaard QUASES software; and (iii) estimation of XPS detection limits and amounts of material in samples with complex morphologies. An overview is also given of a recent evaluation of calculated and measured cross sections for inner-shell ionization by electron impact. New recommendations have been made for K-shell and L- and M-subshell ionization cross sections. These cross sections will be available in a new NIST database that is expected to be released in 2014.

  We would report the repeated survey-spectra acquisition method in order to analyze the instability of the acquired spectrum in Auger Electron Spectroscopy. The experiment followed a sequence of continuous spectral acquisition for one hour and one-hour acquisition halt, while the electron beam irradiation was continued during the acquisition halts. The sequence was repeated three times. The intensity of the survey spectra gradually decreased, and we think this was mainly due to the surface contamination. After excluding the contamination effect, we found that the intensities of spectra revealed the gradual increase by a few percent for the acquisition time less than ~500 s and for all the electron energy examined. In contrast, the rapid intensity increase by one percent was observed for the acquisition time less than ~15 s and for the energy lower than ~600 eV. After a prolonged continuous-acquisition, the stable spectrum was finally derived, however, the acquisition halt disrupted the stable state. We think the observed instability of the spectra intensity was due to the gain fluctuations of a micro-channel plate installed in a cylindrical mirror analyzer.

  A method for estimation of inelastic mean-free path (IMFP or λ) of an unknown material except for an arbitrary proportionality constant c, i.e. λ₀(E) in λ(E)=cλ₀(E), where E is the electron kinetic energy, has been proposed through iteration of background optimization on an XPS spectrum. The dependence of the i-th core peak intensity p_i on its energy E_i given by background optimization is proportional to the product of theoretical photoexcitation cross sections σ_i and the asymmetry factor a_i after analyzer transmission correction. Therefore, any non-parallel behavior between p_i and (σ_i·a_i) is ascribed to λ(E). This enables the estimation of λ₀(E) using p_i and (σ_i·a_i), by assuming the initial λ to be constant, and then repeating background optimization and λ update. Between 700 and 1500 eV kinetic energy (KE) for Au metal, where λ by TPP [Tanuma et al, Surf. Interface Anal., 43,689(2011)], denoted as λ_TPP, is known to be well approximated by a straight line, λ converges to λ_TPP within 2.4 % if c is chosen so that both values coincide at 800 eV. This is remarkably satisfactory because only relative peak intensities are involved in a usual practical analysis and because what is requested for surface analysis is to analyze the sample whose properties including λ are yet to be known.

  Recently, various cluster ion beam sources have been studied with the aim of improving sensitivity in secondary ion mass spectrometry (SIMS) and achieving damage-free etching in X-ray photoelectron spectroscopy (XPS). Thus, compact gas cluster ion beam guns are now available for commercial SIMS and XPS instruments. The electrospray droplet impact (EDI) method was also developed as a new source for massive cluster beam, in which the charged droplet beams are produced from ambient electrospray and introduced into the vacuum system. The EDI method has been successful in achieving efficient ionization of organic molecules, soft etching of polymers, and nonselective etching of metal oxides. However, the current EDI method lacks adequate beam focusing and brightness for practical use. As a solution for these problems, we have proposed and developed a new method for producing a charged droplet beam and a stable electrospray of aqueous solutions under vacuum. In this study, the characteristics of ambient and vacuum electrospray were investigated with optical microscopy, and the ability of vacuum electrospray as the primary beam source will be discussed.

  Atom probe tomography (APT) is a widely used technique to evaluate the atomic structure of semiconductor materials such as the field effect transistor. However, application of the APT technique faces difficulties, among which is the low reliability of reconstruction calculations due to poor understanding of the field evaporation mechanism. In general, lower detection efficiencies are observed in low evaporation field elements that undergo DC evaporation in APT. However, in the analysis of SiO₂ and GaAs, the detection efficiencies of oxygen and arsenic are higher than those of silicon and gallium, even though oxygen and arsenic have higher evaporation fields. To explain these phenomena, we evaluated the potential for neutral desorption from the sample surface without ionization in the APT analysis. We observed changes in the detection efficiencies of arsenic and phosphorus during analysis of InGaAsP, when the laser power and initial temperature were varied. This was attributed to increases in the temperature of the surface atoms during irradiation of the pulsed laser. Therefore, under the ultrahigh vacuum conditions applied in the experiment, the low vapor pressure elements might have experienced sublimation.

  The three-dimensional stacking technology of heterogeneous devices is one of the most effective methods to realize high-performance devices without scaling down. The through-silicon via interconnect process is the most commonly for that purpose. The technology that measures the depth of the high aspect via hole with high accuracy is indispensable for metal contamination-free via-middle processes. Displacement measurements from the surface using interference spectra are more accurate compared with measurement from the back side. However, because such a system is not presently available, we decided to build one for trial purposes. As a result, we successfully build a system that was able to directly measure a high aspect via hole (diameter: 3.3 μm; aspect ratio: 15) by using a spectrum interferometer. We believe that this technology can use in the production of next-generation 3D devices for supercomputer.

  A novel method with quaternary ammonium salts as internal additives has been applied to the mass scale calibration of time-of-flight secondary ion mass spectrometry (TOF-SIMS). Five kinds of quaternary ammonium salts, octyltrimethylammonium bromide (C8TMA), tetradecyltrimethylammonium chloride (C14TMA), octadecytrimethylammonium chloride (C18TMA), cetylpyridinium chloride (CPC) and benzyldimethyltetradecylammonium chloride (Bzl) were diluted with distilled water and conc-NH₃ and were mixed in equal quantities. The solution was added to Tinuvin 770 coated on a Si wafer. Then, the sample was measured by TOF-SIMS. The relation between the relative mass accuracy of molecular ions of Tinuvin 770 and the combinations of ions selected for the mass scale calibration was investigated. To improve the mass accuracy of the molecular ion of Tinuvin 770, ions should be selected for the mass scale calibration in the following two ways: one way is for ions to consist only of molecular ions of C8TMA, C14TMA and C18TMA, and the other way is for ions to include the molecular ion of C18TMA, along with the C_XH_Y fragment ions. These results support the proposition of ISO 13084. The novel method with internal additives is effective to improve the mass accuracy of high-mass ions. Quaternary ammonium salts are potential candidates of internal additives.

  Improvement of bainitic hardenability is outstanding feature of the boron addition into iron and steel. It is well established that a hardenability peak is accomplished when the concentration of boron is about several to several tens of weight ppm. In the previous study, resistive anode encoder (RAE) of the secondary ion mass spectroscopy (SIMS) was used to map the distribution of ppm of boron in iron and steel with the overall quantification using cluster-polyatomic secondary ion species for both impurity, I_i and matrix, I_m to reduce the matrix effect. The quantification of the boron was proposed by retrospective depth profile from the RAE boron map. In this study, the relative sensitivity factors (RSFs) and calibration curve of the standard reference materials were examined and calculated to identify the dissolved boron concentration which might be originated from poly crystal boron nitride (PCBN) tool in friction stir welding (FSW) for steel samples. Retrospective depth profile and linear regression of the calibration curve provides the boron quantification in FSW steel samples. Dark contrast areas on the FSW steel samples were indentified higher boron concentration than bright areas. It is accounted that the combination of ¹¹B¹⁶O₂ and ⁵⁶Fe¹⁶O as for I_i / I_m is a useful method of SIMS quantification from boron image in iron and steel with minimal number of standard reference materials.

  Segregation volume is an important quantity controlling the pressure effect on grain boundary chemistry. In the present paper, we define molar segregation volume on basis of fundamental thermodynamics and evaluate it for example of phosphorus and sulfur grain boundary segregation in low-alloy ferritic steels including its development during non-equilibrium segregation under tensile and compressive deformations. We also show expected effect of anisotropy on equilibrium segregation under pressure.

  Two on-site nondestructive methods, one involving an electromagnetic thickness tester and the other a handheld x-ray fluorescence analysis system, were used to evaluate thicknesses of hot-dip galvanized coatings on steel and compared with destructive analytical methods. They were sufficiently applicable for measuring the remaining thickness or mass of the coatings when the density of the alloy layer or the zinc depth profile was already known.

  Laser-assisted atom probe tomography (APT) and Auger electron spectroscopy (AES) were applied to examine the elemental distributions in Ta/NiFe/Ta/CoFeB/Ta/NiFe multilayer thin films. The impact of APT analysis direction on the elemental distributions of atoms which evaporate at high field could be seen. In particular, B atoms appeared deeper within the CoFeB layer along the analysis direction in APT due to its artifact. On the other hand, B atoms were homogeneously distributed in CoFeB layer with AES analysis.

  In this study, we demonstrate low damage etching of titania for depth profile analysis using large Ar cluster ions. Sample damage caused by impinging ion beams is discussed and a comparison is made between monatomic Ar⁺ ions and Ar_n⁺ cluster ions with respect to surface damage. Monatomic ions of beam energy 5 kV cause considerable changes to the structure of amorphous titania resulting in the preferential removal of oxygen and damage to the lattice structure. Titanium is reduced from the +4 oxidation state to +3 and +2 oxidation state during this preferential removal. In contrast, the use of clusters greatly diminishes this damage and also reduces the incorporation of the impinging ion into the sample surface. Here we discuss the use of Ar_n⁺ clusters as a new methodology for reducing the damaging effects caused by ion bombardment.

  The degradation of organic materials was often observed during XPS measurement. We have evaluated the degradation of silicon wafers modified with 3,3,3-trifluoropropyltrimethoxysilane (F3PTMS-Si), 3-chloropropyltriethoxysilane (CPTES-Si), 3-bromopropyltrimethoxysilane (BPTMS-Si) and 3-iodopropyltrimethoxysilane (IPTMS-Si), and gold substrate modified with 1H,1H,2H,2H-perfluorodecanthiol (PFDT-Au) as reference material in order to investigate influence of C-F, C-Cl, C-Br and C-I bonds in the organic silane monolayers. As a result, the order of damaging factor, β, was IPTMS-Si > BPTMS-Si > CPTES-Si > F3PTMS-Si. It was found that the value of β was related to the chemical bond energy of C-X(X=F, Cl, Br, I).

  Oxidation reaction efficiency of the embedded Si atoms in the diamond-like carbon (DLC) film was studied with a combination of the broad O-atom beam, high-speed chopper wheel and synchrotron radiation photoelectron spectroscopy (SR-PES). The high-speed chopper wheel converted the translational energy distribution of O-atom into spatial distribution on the DLC surface. High spatial and energy resolutions of SR-PES allow studying the difference in oxidation states of Si atoms in different translational energies. It was confirmed that the SiO₂ was formed by the high-energy collision conditions of O-atoms, whereas sub-oxides are formed with the low-energy collisions. The efficiency of SiO₂ formation at 9 eV-collision is evaluated to be 4 times greater than that at 2 eV-collision.

  Surface relief grating of azobenzene polymer formed on a soda-lime-silica glass plate was treated by corona discharge for the formation of a hologram on the glass plate. The Na concentration distribution near the glass surface was investigated using a time-of-flight secondary ion mass spectrometry (TOF-SIMS) depth analysis with buckminsterfullerene (C₆₀) ion sputtering and an image processing. The periodical Na deficient region identical to the azobenzene grating pattern existed near the glass surface, which suggested that the Na ions below the grating groove preferentially migrated to the cathode side during the corona discharge treatment. Generally, the refractive index of the Na poor region becomes lower than that of the pristine soda-lime silica glass. Therefore, the origin of the hologram on the glass surface should be the three-dimensional distribution of refractive index at the glass surface.

  The PC liposomes constructed with one lipid bilayer have been fabricated without using chloroform solution and phosphate-buffer saline. After reaction promotion, the Au NPs covered with PC molecules exist on the outside of the liposome membrane. The thickness of the liposome membrane is estimated to be approximately 5 nm.