Quantitative de terminations of thickness and composition are presented for 100- to 10,000-A iron-nickel films. Calibration of X-ray intensities with interferometric and calorimetric values give linear plots for films deposited on Mylar or glass substrates. Application of a film-casting technique shows promise of alleviating two of the problems encountered in X-ray spectroscopy, i.e., matrix-effect-caused deviations from proportionality and the lack of standards for calibration of many types of material.

We have developed an algorithm for calculating the x-ray tube continuum based on the eqidistribution proposed by Love and Scott, extended the description of white and characteristic radiation given by Wiederschwinger et al for the energy range 10 to 50 keV to the low energy range from 5 to 30 keV, and compared the results from this algorithm to those responses obtained from algorithms using the absorption correction of Pochou and Pichoir, Philibert, Sewell and Pella. The comparison to other models showed a significandy better performance by our model.

The primary X-ray analyzer is used for nondestructive spectrochemical analysis of solid specimens. Accelerated electron beams bombard the specimen surface directly and generate primary X-rays which are measured in a vacuum spectrometer. The method of primary X-ray spectroscopy is superior to the fluorescence X-ray spectroscopy because (1) detectable sensitivity for such light elements as magnesium and aluminum is very high, and (2) the correction of the measured value for self-absorption of X-rays by the specimen itself is low. The performance of the instrument and applications are reported.

A micro fluorescent X-ray analyzer with a focusing type of spectrometer has been developed to analyze samples of small amounts such as extracted inclusions or precipitates from metals or small areas in samples from 0.1 to 2.0 mm in diameter. This instrument is expected especially to analyze powder samples of small quantity because average values from such samples can be obtained and because surface conditions of the samples scarcely affect the results compared with their effect in electron probs microanalysis. A commercial X-ray tube is combined with a device of slits limiting incident X-rays, a focusing spectrometer with a Rowland circle of 4-in. radius, and a microscope of low magnification for observing the analyzing point on the samples. The wavelength range of the spectrometer with LiF and ADP analyzing crystals is from 1.20 to 9.94 Å, and, therefore, higher elements than aluminum in atomic number can be analyzed. The authors exerted their efforts to obtain the higher X-ray intensities in order to analyze smaller areas. The X-ray intensities obtained are satisfactory, except for light elements. For example, the detected X-ray intensity of pure nickel is 1650 cps with the use of a 0.1-mm diameter specimen, and that of pure sulfur is 52 cps with the use of a 0.1-ramdiameter specimen; however, with a 1-mm-diameter specimen, the intensity of pure nickel is over 5000 cps and that of pure sulfur is 1650 cps. These correspond to the intensities from 20-mm-diameter specimens of those elements when a flat-crystal spectrometer is used. The calibration curve for quantitative analysis generally varies with the sample area under analysis, but the same curves are obtained if the sample area is larger than 1 mm in diameter. Then, powder samples are analyzed quantitatively by using a plastic sample holder of 1-mm diameter and 0.3-mm depth. This instrument has good ability for microanalyzing trace elements by, for example, the ion-exchenge membrane method. The sensitivity represented is nearly 5000 cps/μg for Ni Kα from NiSO4 that is soaked and dried in thin rice paper. Some applications of the micro fluorescent X-ray analyzer to precipitates in steels and corrosion products are reported.

A review is given of the main gas-discharge sources and auxiliary equipments which were used in soft and ultra-soft X-ray emission spectrometry. Special attention is paid to the basic principles and instrumentation of low-energy electron-induced X-ray spectrometry (LEEIXS) whose excitation source is an electron beam generated in a glow-discharge system. Capabilities of LEEIXS in surface and thin film analysis and characterization are illustrated by examples dealing with control and optimization of surface treatment and thin film deposition processes. Sensitivity of the technique down to the submonolayer range and influence of backscattering phenomena are shown.

Methods for rapid and accurate analysis of coating composition and thickness are of major importance for the semiconductor industry. Typical coating problems are Al, Au or Pt coatings on metal and Cr/Ni alloy or SiO2/P2O5 glass on Si wafers. Due to the nature of the coatings ana tne variety of elements, a software package, COAT95 has been developed to cover the following three possible situations:

• 1. Single element coating for thickness only.

• 2. Compound, elements A and B, coating on substrate element S, for composition and thickness.

• 3. Compound, elements A and S, coating on substrate element S , for composition and thickness.

The main goal of the COAT95 software is to have all possible models for the single layer coating problems of the semiconductor industry.

Measurements have been made on the FeLII/LIII intensity ratio on oxide free iron surface produced by evaporating a 50 Å Ti film on iron. These results show that the reported increase in the FeLII/LIII ratio with decreasing accelerating voltages is due largely to surface oxide and not self absorption. Also, for the vacuum presently used by soft x-ray spectroscopists the oxide surface on metals contribute strongly to the soft x-ray spectra of the bulk material for accelerating voltages below 4 kV.

The development of X-ray fluorescence analysis of light elements (e.g. O, C, B and Be) has been carried out for many applications. Recently, the revolutional expansion of semiconductor electronic and memory devices has roused the needs of analysis and identification of the surface and the single- and multi-layered film structure in devices, using the fundamental parameter method for the soft and ultrasoft X-ray region. From the view point of the extensive studies of soft and ultrasoft X-ray measurements.

Nonlinear sin2ψ curves are often obtained in X-ray stress measurement. One of the reasons, for non-textured materials, is a steep stress gradient snowing in a surface layer of a sample. Regarding such experimental results, several new principles have been developed for X-ray stress analysis. At the present stage, we can evaluate the stress gradient in a triaxial stress state. As the next stage of the investigation, it is necessary to consider the validity of the assumptions taken in the principle, especially, the assumption about linear distribution of stress along the depth direction.

Depth profile analysis of phase composition, residual strain and crystallite size in ceramic specimens can be determined by varying the information depth (ID) as defined by Delhez et al. (1988) for an x-ray opaque specimen. The information depth may be controlled by making use of the dependence of ID on Bragg angle and by selecting wavelengths which give appropriate x-ray absorption within the specimen.

Procedures are outlined for extracting depth profiles for (i) composition from intensity data and (ii) residual strain and crystallite size from peak width data. Results are described for both discrete-peak and Rietvetd pattern-fitting analysis of zirconiaalumina specimens for which preliminary results have been reported by van Riessen et al. (1990).

The continuing development in recent years of mercuric iodide room temperature x-ray spectrometers has led to steady improvment in the spectral energy resolution capability of these systems. This has been due largely to the continuing reduction in the electronic noise level of the associated preamplification electronics. It has been demonstrated that a system consisting of a mercuric iodide detector in combination with a pulsed-optical feedback preamplifier provides superior energy resolution performance in x-ray spectrometry in comparison to the other types of preamplification. Previously, results have been reported by us of the energy resolution of such systems with both the detector and input FET of the preamplifier at room temperature and with the input FET cooled by liquid nitrogen and the mercuric iodide x-ray detectors lightly cooled.

The lattice misfits between γ and γ' phases in Ni-base superalloys (single crystal) were accurately determined for filings of specimens by using both a conventional X-ray tube focusing diffractometer(CXRFD) and a synchrotron-radiation parallel beam X-ray diffractometer (SRPXRD). All reflection peaks measured with the CXRFD were in a cluster of overlapping peaks because of the very small differences in the lattice parameters of both phases and the instrumental broadening due to X-ray optics including the spectral distribution of Xray source such as CuKα doublet. The deconvolution method was applied to remove the instrumental broadening from the peaks measured with the CXRFD. The window functions for the deconvolution method were calculated from CuKα doublet reflection of Si standard by a nonlinear least-square method.

The instrumental broadening of SRPXRD was much smaller than that of CXRFD since the monochromatic X-rays produced single peak profiles and constant profile shape over a wide 2θ range. A profile fitting with a pseudo-Voigt function was used to determine 2θ angles to 0.0005 deg. for the synchrotron powder data. The peak angle and shape reflected from γ' phases in γ-matrix and those fron electrochemically extracted γ'-phase were significantly different.

This paper briefly traces the study of the preprecipitation or cold-aging stage of the decomposition of supersaturated solutions by means of diffuse scattering of X-rays.

This part of the overall precipitation process is of considerable practical as well as theoretical interest because it is during preprecipitation that changes in many physical and mechanical properties take place without the formation of a precipitate phase.

Examples will be given to show the types of zones encountered during this stage in various age-hardening alloys. These will attempt to illustrate the contribution which the study of diffuse scattering of X-rays, guided by present-day concepts of crystal imperfections, has made toward a better understanding of the precipitation process in alloys.

The properties of particle-induced X-ray emission, PIXE, and secondary target mode X-ray fluorescence, XRF, applied to the analysis of unprepared drill cores in open air have been evaluated. Typical detection limits for elements heavier than Mg have been determined for a PIXE-system with an external 2.55 MeV proton beam and for an XRF-system with Ti, Mo and Tb secondary targets. These two systems were found to have similar detection limits for most elements in a typical geological sample. The heterogeneous composition of drill cores prevents the performance of accurate matrix corrections, though calculations using fundamental parameters show that in the PIXE analysis of elements heavier than Ca, these corrections are much less sensitive to variations in the matrix composition than in the XRF analysis.

Cemented carbide composites with a WC hard phase and a Co-Ni alloy binder phase have been subjected to monotonic and cyclic deformation and studied using the high resolution General Purpose Powder Diffractometer at the Argonne Intense Pulsed Neutron Source. Upon deformation, relaxation of bulk differential thermal residual stresses, tensile in the binder and compressive in the carbide, is observed to occur as a function of loading mode and plastic strain via shifts in diffraction peak positions. In addition, peak breadth behavior indicates broadening. At low plastic strain this is due primarily to a range of residual stress and at high plastic strain it is attributable to the plastic deformation alone since relaxation is essentially complete. The appropriateness of neutrons is discussed.

A design is described for a variable-temperature diffractometer specimen mount developed internally in the Physics Laboratory of Materials Central. Temperature capability of 1600°C is achieved using Indirect radiation heating. Higher temperatures may be obtained by directly heating the sample. An adaptation allows operation at temperatures as low as −196°C and is useful for studying low-temperature phase changes and examining materials normally liquid at room temperature. The mount operates in vacuum or inert atmosphere. A full 180° 2θ scanning range is possible through the use of curved beryllium- or aluminum-foil windows. Realignment of the sample at temperature and under vacuum may be accomplished from four points around the front plate of the mount. Only two vacuum seals are used In this mount in addition to the window seal and thermocouple seals. Power for the mount is high current, low voltage, and is controlled by an automatic temperature regulator and sensing device which maintains an accurate preset temperature.

Applications of variable temperature techniques on refractory metals, alloys, and compounds are shown, along with an example of low-temperature effects in materials normally liquid at room temperature.

A numerical procedure known as the constrained linear inversion method is employed for obtaining the z-profiles of diffraction data from their τ-profiles. The method was first tested with known z-profiles and gave good agreement with the starting z-profiles even with up to 5% random noise introduced into the τ-profile or up to 10% error in specimen thickness. The procedure was then applied to an experimentally obtained strain profile and a non-oscillatory z-profile was calculated. Although the z-profile obtained could not be verified by an independent method, the success of tests with known z-profiles leads to increased confidence in the numerical method described.

Art X-ray spectrographic technique requiring no calibration curves is used to determine chlorine, bromine, and lead in automotive combustion deposits. Other elements, such as zinc and barium, can probably be determined by the same X-ray technique. The inert dilution method, described by Sherman in 1957, is employed. Improvements in sample preparation have been made to make the procedure more reliable. Results are calculated by the use of a formula, which is shown to be valid even though sample and standard have composition differences which cause interelement-effect errors if calibration-curve techniques are used. Adequate agreement is obtained between the inert dilution X-ray method and chemical procedures.

Given the vast superiority of synchrotron radiation sources for EXAFS and near-edge measurements, one might assume that conducting such experiments in the laboratory is a waste of time and resources. Upon more careful consideration of the realities of everyday research, however, one can easily see that this is not true. In fact, many people have come to this realization, so much so that a whole conference has been devoted to laboratory EXAFS facilities, their role in research and their relation to synchrotron facilities. The concensus after the conference was that laboratory instruments can and have been developed, with adequate performance for a variety of nontrivial experiments. They usually employ dedicated focusing spectrometers, rotating anode generators and fairly expensive monochromator crystals (see articles in ref. 1 and 2).