The term "ceramics" covers a very broad range of materials. By definition, ceramies include all nonmetallic inorganic solids, containing both nonmetallic and metallic constituents ; the interatomic bonds thus usually have both ionic and covalent character. The usefulness of ceramies in a wide variety of applications sterns from properties such as hardness and resistance to heat, corrosion, and electricity. Ceramies are sometimes divided into two groups known as "traditional ceramics" and "new ceramies" (Kingery et al., 1976). The traditional ceramies include those primarily in the silicate industries (e.g ., whitewares) and refractories. The new ceramies include electro-optic ceramies, magnet ic ceramics, single crystals used for thin-film substrates, those used in the nuclear industry, and pure oxide ceramies to name a few (Kingery et al., 1976). The study of ceramies using electron backscatter diffraction (EBSD) has not yet extended into all of these areas of ceramics. However, EBSD research of certain ceramies has received considerable attention, and this will be the focus ofthis review.Ceramies used in many applications today are polycrystalline and polyphase materials with grain sizes that typically vary between about 0.1 and 10 um; this range of grain sizes means that x-ray diffraction (XRD) usually cannot be used to determine local crystal orientations. In addition, many ceramies possess a complex crystal structure coupled with anisotropie materials properties, making routine transmission electron .microscopy (TEM) analysis difficult. The phase and orientation of the grains, and the properties and microstructure of the grain boundaries , have a large influence on the useful properties of these materials. Therefore, it is essential to have a characterization technique that can readily provide information such as grain size, orientation, and phase. In this context, EBSD can make extensive contributions to the crystallographic and structural analyses of

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As nanoscale systems are increasingly incorporated into industrial products, an understanding of defect behavior and interfaces in these materials is critical. Because of the inherently small dimensions of the "nano" regime, characterization of nanoparticle-based systems demands high resolution. The transmission electron microscope (TEM) is uniquely suited for this task, although its resolution is limited by the aberrations present in electromagnetic lenses [1].

Recent work has shown that the electrical properties of hydrogenated amorphous Si films with nanocrystalline inclusions (a/nc-Si:H) make this material a promising candidate for applications in solar cells. The present study applies the technique of spherical aberration-corrected high-resolution transmission electron microscopy for the identification and analysis of the crystalline content of an a/nc-Si:H film. By varying both the spherical aberration of the objective lens and the defocus, regions of crystallinity in the a/nc-Si:H film can be identified. This study reports the analysis of Si nanoparticles of approximately 1.5 nm in size. Some of these nanoparticles contain planar defects, such as twin defects and stacking faults. All particles observed were the same crystal structure as bulk Si, which agrees with theoretical cluster calculations. Beam damage was observed in the amorphous matrix for long electron–beam exposures.

Faceting is the transformation of a planar surface into two or more surfaces of lower energy. Metal, semiconductor and ceramic surfaces can all undergo faceting. The evolution of facets formed on the m-plane (1010) of alumina has been monitored using atomic-force microscopy (AFM). When heat-treated, the (1010) surface reconstructs into a hill-and-valley morphology. The present study investigates the manner in which facets originally form and grow to cover a surface. A gravity-loaded indenter (load of 25 grams) was used to mark a 25 μm × 25 μm square area on as-received, polished alumina specimens. An initial heat-treatment of 1400°C for 10 minutes is carried out to initiate faceting. With the indents as guides the same area can be identified and imaged after each subsequent heat-treatment. The morphology of the facets can be described as being comprised of a “simple” and “complex” surface. The simple surface corresponds to the (1102) plane which is stable over the course of heat treatments, whereas the complex surface gradually transforms to a lower energy surface after several heat treatments and acts as a nucleation site for new facet growth.