Materials characterization instrument

A major challenge in developing techniques for characterizing film materials is the limited amount of material present. For example, in a one-micrometer-thick film, there is only 10 cm of material for each cm of film area. Thus, a 10-cm film has a volume of only one microliter and a mass on the order of one milligram. Many material characterization instruments do not have sufficient sensitivity to analyze these small volumes or masses [9], In addition, those tech-... 

The type and sophistication of materials characterization instrumentation made available for a given IC facility will depend on several factorsi oost/benefit, quality perceptions, process complexity, maturity of the process. Commercial support labs are becoming more readily available to meet the VLSI challenge. The mix of in-house versus external laboratory support then becomes a matter of choice based on considerations of sample turn-around time, maintaining security of proprietary devices or processes, and outside versus inside expenditures. 

The diagnostics applied to shock experiments can be characterized as either prompt or delayed. Prompt instrumentation measures shock velocity, particle velocity, stress history, or temperature during the initial few shock transits of the specimen, and leads to the basic equation of state information on the specimen material. Delayed instrumentation includes optical photography and flash X-rays of shock-compression events, as well as post-mortem examinations of shock-produced craters and soft-recovered debris material. 

Traditionally, the first instrument that would come to mind for small scale materials characterization would be the optical microscope. The optical microscope offered the scientist a first look at most samples and could be used to routinely document the progress of an investigation. As the sophistication of investigations increased, the optical microscope often has been replaced by instrumentation having superior spatial resolution or depth of focus. However, its use has continued because of the ubiquitous availability of the tool. 

For the purpose of a detailed materials characterization, the optical microscope has been supplanted by two more potent instruments the Transmission Electron Microscope (TEM) and the Scanning Electron Microscope (SEM). Because of its reasonable cost and the wide range of information that it provides in a timely manner, the SEM often replaces the optical microscope as the preferred starting tool for materials studies. 

ICP-OES is one of the most successful multielement analysis techniques for materials characterization. While precision and interference effects are generally best when solutions are analyzed, a number of techniques allow the direct analysis of solids. The strengths of ICP-OES include speed, relatively small interference effects, low detection limits, and applicability to a wide variety of materials. Improvements are expected in sample-introduction techniques, spectrometers that detect simultaneously the entire ultraviolet—visible spectrum with high resolution, and in the development of intelligent instruments to further improve analysis reliability. ICPMS vigorously competes with ICP-OES, particularly when low detection limits are required. 

In electron-optical instruments, e.g. the scanning electron microscope (SEM), the electron-probe microanalyzer (EPMA), and the transmission electron microscope there is always a wealth of signals, caused by the interaction between the primary electrons and the target, which can be used for materials characterization via imaging, diffraction, and chemical analysis. The different interaction processes for an electron-transparent crystalline specimen inside a TEM are sketched in Eig. 2.31. 

Williams-Thorpe, O., S. E. Warren, and J. G. Nandis (1997), Characterization of obsidian sources and artefacts from central and eastern Europe, using instrumental neutron activation analysis, in Korek, J. (ed.), Proc. Int. Conf. Lithic Raw Material Characterization, Budapest and Siimeg, 1996, Budapest. 

Development of a linked network of expert systems, EXMAT, has been described for application to materials characterization. Selected instrumentation which are common to modern laboratories generate databases that are treated and interpreted within an analytical strategy directed toward a desired goal. Extension to other problem-solving situations may use the same format, but with specialized tools and domain-specific libraries. Importantly, a chemometrician s expertise has been embedded into EXMAT through access to information derived from a linked expert system,... 

Electron microscopy is an efficient microscopy technique that has been extensively used for the material characterization of artistic and archaeological objects, especially in combination with x-ray microanalysis [54], The use of electrons instead of light in these instruments is the basis of the higher resolution ( 9-0.2 nm) and has greater depth of held than LM. Thus, characterization of the finest topography of the surface objects is possible, and additional analytical information can be obtained. Different electron microscopes are currently used in art and art conservation studies scanning electron microscopes (SEM), Cryo-SEM... 

A recent survey has shown that our first polymer standard samples are widely distributed and used in research and industry for the calibration of a variety of characterization instruments, particularly gel-permeation chromatographs. They also serve as materials with well defined properties for research in many areas. These properties should become better defined with time as results accrue in the literature. 

G. C. Adams, Materials Characterization by Instrumented Impact Testing, in... 

Characterization of materials in the solid state, often loosely referred to as materials characterization, can be a vast and diverse field encompassing many techniques [1-3]. In the last few decades, revolutionary changes in electronic instrumentation have increased the use of highly effective automated instruments for obtaining analytical information on the composition, chemistry, surface, and internal structures of solids at micrometer and nanometer scales. These techniques are based on various underlying principles and cannot be put under one discipline or umbrella. Therefore, it is important first to define the scope of techniques that can be covered in one chapter. 

A process for forming a ZnS insulative layer on an HgCdTe material characterized by the absence of an intermediate native oxide layer is taught in EP-A-0366886 (Texas Instruments Incorporated, USA 09.05.90). 

This chapter focuses on the use of fluidized bed granulation process in the development and preparation of low-dose granule formulations for further conversion to immediate release tablets for personal administration. As a reference document, the chapter does not cover some very common subjects such as process safety, material characterization techniques and basic process and instrumentation technologies. Because the authors intention is to relate their experience in this specialized area, these areas are not discussed in any depth however their omission does not reduce their importance. 

Cygnus Instruments, UK UVM1 Sound velocity Materials characterization Yes Yes... 

Malvern Instruments, UK (http //www.malvern.co.uk) Ultrasizer Attenuation spectroscopy Particle sizing and materials characterization No Yes... 

The resolution of SEMs is now suitable for nano-materials characterization. High resolution SEM is a powerful instrument for imaging fine structures of materials and nanoparticles fabricated by nanotechnology. In lens SE, BSE modes, and STEM mode are often performed to check the structure of CNT growths or CNT as delivered by commercial producers, and sometimes coupled with TEM. Even the single-walled carbon nanotubes can easily be observed by HR-SEM (see Figure 3.13). The STEM mode can also be used for free CNT observation (75). 

It is worth noting that unlike the instrumental and wavelength dispersion functions, the broadening effects introduced by the physical state of the specimen may be of interest in materials characterization. Thus, effects of the average crystallite size (x) and microstrain (s) on Bragg peak broadening (P, in radians) can be described in the first approximation as follows ... 

The powder diffraction experiment is the cornerstone of a truly basic materials characterization technique - diffraction analysis - and it has been used for many decades with exceptional success to provide accurate information about the structure of materials. Although powder data usually lack the three-dimensionality of a diffraction image, the fundamental nature of the method is easily appreciated from the fact that each powder diffraction pattern represents a one-dimensional snapshot of the three-dimensional reciprocal lattice of a crystal. The quality of the powder diffraction pattern is usually limited by the nature and the energy of the available radiation, by the resolution of the instrument, and by the physical and chemical conditions of the specimen. Since many materials can only be prepared in a polycrystalline form, the powder diffraction experiment becomes the only realistic option for a reliable determination of the crystal structure of such materials. 

FTIR spectroscopy can combine with microscopy for generating FTIR spectra from microscopic volumes in materials. The instrument for FTIR microspectroscopy is simply called the FTIR microscope, which is often attached to the conventional FTIR instrument. The FTIR microscope is increasingly used for materials characterization because of its simple operation and FTIR spectra can be collected rapidly from microscopic volumes selected with the microscope. 

Raman microscopes are more commonly used for materials characterization than other Raman instruments. Raman microscopes are able to examine microscopic areas of materials by focusing the laser beam down to the micrometer level without much sample preparation as long as a surface of the sample is free from contamination. This technique should be referred to as Raman microspectroscopy because Raman microscopy is not mainly used for imaging purposes, similar to FUR microspectroscopy. An important difference between Raman micro-and FUR microspectroscopies is their spatial resolution. The spatial resolution of the Raman microscope is at least one order of magnitude higher than the FTIR microscope. 

Static SIMS. The static SIMS instrument was briefly described in the instrumental section. Static SIMS has been applied to the study of metal surfaces (fig.) oxide formation (11), and catalysts (ii fi6) but static SIMS is not widely used in microelectronics materials characterization. A major limitation of static SIMS for microelectronics applications is the inability to obtain a detectable signal from a very small area on the sample. The low energy low current density primary ion source used in static SIMS produces a lower count rate per unit area of sample than does the higher energy higher current density used in dynamic SIMS. 

Grffnbfrg RR (1986), Elemental characterization of the National Bureau of Standards Milk Powder Standard Reference Material by instrumental neutron activation analysis. Anal Chem 58 2511-2516. 

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