Morphology analytical techniques

The physical techniques used in IC analysis all employ some type of primary analytical beam to irradiate a substrate and interact with the substrate s physical or chemical properties, producing a secondary effect that is measured and interpreted. The three most commonly used analytical beams are electron, ion, and photon x-ray beams. Each combination of primary irradiation and secondary effect defines a specific analytical technique. The IC substrate properties that are most frequendy analyzed include size, elemental and compositional identification, topology, morphology, lateral and depth resolution of surface features or implantation profiles, and film thickness and conformance. A summary of commonly used analytical techniques for VLSI technology can be found in Table 3. 

Having said this, it was felt therefore that there is a need for a book addressing analysis and characterisation of polymers from the point of view of what we wish to call the primary analytical question. Many excellent textbooks and reference works exist which address one or more individual analytical techniques, see, for example, references [1-10]. These books form the basis of the knowledge of the technique expert. They also contain many excellent and varied examples on successful applications of analytical techniques to polymer analysis and characterisation. There are also books which address the multitude of analytical techniques applied in polymer analysis, see, for example, references [11-24], However, a synthetic chemist may wish to know the constitution of his/her polymer chain, a material scientist may want to find out the reasons why a fabricated sample had failed. What technique is best or optimal to study chain constitution will depend on the situation. Polymer failure may result from morphological features, which needs to be avoided, a contaminant, a surface property degradation, etc. When a sample has been processed, e.g., a film blown, molecular orientation may be the key parameter to be studied. A formulation scientist may wish to know why an additive from a different supplier performs differently. It is from such points of view that polymer analysis and characterisation is addressed in this book. 

In addition to surface analytical techniques, microscopy, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning tunneling microscopy (STM) and atomic force microscopy (AFM), also provide invaluable information regarding the surface morphology, physico-chemical interaction at the fiber-matrix interface region, surface depth profile and concentration of elements. It is beyond the scope of this book to present details of all these microscopic techniques. 

The chapters in this volume present a concise overview of surface analytical techniques from the specific viewpoint of surface morphology and its modification at the polymer-metal interface. A consistent picture begins to emerge of the chemical reactions occurring on metal deposition and why this leads to metal adhesion. The coeditors hope this information will be timely and useful. 

X-ray diffraction technique is a non-destructive analytical technique that reveals information about crystallographic structure, chemical composition and physical properties of nanostructured materials. UV/Vis spectroscopy is routinely used in the quantitative determination of films of nanostructured metal oxides. The size, shape (nanocomb and nanorods etc,) and arrangement of the nanoparticles can be observed through transmission electron microscope (TEM) studies. Surface morphology of nanostructured metal oxides can be observed in atomic force microscopy (AFM) and scanning electron microscopy (SEM) studies. 

Simultaneously, as articulated above, it is realized that intrinsically new phenomena may occur on the nanoparticles, which cannot be deduced from the knowledge obtained from single crystals, due to changes in the electronic structure [3], morphology [3,6], and kinetics of nanometer scale particles [4] (Fig. 4.3). This is in essence what the structure gap in catalysis is about. Clearly, it is desirable to devise better methods to prepare model catalysts, which not only maintain the critical aspects of their original function but also provide a well-defined structure that allows for detailed scrutiny with a large range of analytical techniques (experimental and theoretical). 

Providing a comprehensive characterization of pharmaceutical dosage forms requires a multi-instrumental approach as no single surface analytical technique can ascertain both the chemical and morphological nature of the surfaces. To this end, SPM, XPS, and ToF-SIMS have been used as complementary techniques with which to characterize the surface nature of dosage forms (141,143-145). 

Many poly(imide)s are insoluble in their processed form, either because of interchain charge-transfer interactions, or because of the presence of crosslinks in cured poly(imide) resins. The range of analytical techniques available to characterize processed poly(imide)s is therefore limited. NMR spectroscopy, and in particular solid-state NMR [1-3], has an important role to play in the determination of structure, conformation, morphology and molecular motion in poly(imide) materials. The aim of this chapter is first, to briefly summarize the various classes of poly(imide)s, second, to review the current literature on NMR of these materials and finally, to hopefully indicate where NMR spectroscopy will make further additions to the knowledge of the properties of poly(imide)s. 

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