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Microstructures of the NiFe/AlOx/NiFe magnetic tunnel junctions and the barrier shape profile have been studied with atomic resolution using high-resolution electron microscopy and electron holography. A clear relationship between the growth morphologies of the electrodes and the quality of the barrier has been obtained. Although the bottom interface between electrode and barrier is very sensitive to the oxidation condition, a sharp interface can be achieved in optimumally oxidized junctions. The top interface, on the other hand, is always slightly oxidized due to the three-dimensional growth of top electrode above the barrier, independent of the oxidation condition of the barrier. Furthermore, charge accumulation seems to exist at the sharp interfaces. It is also interesting, yet surprising, that both interfaces are actually sharp in underoxidized junctions. Furthermore, charge accumulation seems to exist at the sharp interfaces.

Oxygen arrangement on Hg0.5Tl0.5Ba2CuOx (100) surface was studied by high-resolution electron microscopy. The {100} planes were found to be stable and to have preferred atomic surface. A surface structure model of Hg0.5Tl0.5Ba2CuOx was proposed and compared to the image calculations, which indicated the surface consists of Ba layers and oxygen atoms on the (Hg, Tl) layers. The present work indicates that the stable {100} planes of Hg-1201-type superconducting oxides would be suitable for the future device application.

The structures of light emitting porous and nanocrystalline silicon films have been investigated using high resolution electron microscopy. A pseudo-ordered structure has been found from the Fourier transformation of the high resolution images after digital processing of the images. The structure description was distinguished from common amorphous and nanocrystalline silicon films. The formation mechanism of the pseudo-ordered structure is described in the letter.

GaN layers having the zinc blende and wurtzite structures can be selectively deposited on (111)A and (111)B GaAs substrates by varying the growth temperature. Using the growth temperature as a variable, layers having the two structures have been sequentially deposited. The as‐grown structures have been examined by cross‐sectional high resolution electron microscopy. Results indicate that the two phases once formed are structurally stable in the temperature range examined. Furthermore, the transition from GaN (zinc blende) to GaN (wurtzite) is sharp, whereas a faulted region is observed during the reverse transition. Arguments have been developed to rationalize these observations.

Nanoprecipitates in YBa2Cu3O7‐δ(YBCO) thin films have been identified by high resolution electron microscopy (HREM) as Y2O3 inclusions; they correspond to two different types of epitaxial relationships namely [001] or [110] parallel to the YBCOc‐axis. The [001] precipitates are situated near the YBCO surface, in the bulk and on the YBCO film/substrate interface. The [110] precipitates have only been observed at the surface. Literature data have been reinterpreted.

High resolution electron microscopy (HREM) has been used to study misfit dislocations of ZnSe films grown on vicinal Si(001) substrates tilted 4° towards the [110] axis. In images taken with the electron beam parallel to the [110] direction, 60° dislocations were found to predominate whereas mostly Lomer dislocations or closely spaced 60° dislocations (separated by

The fabric of high‐Tc Nb3Ge superconducting material synthesized by coevaporation in the vacuum has been investigated using 200‐kV high‐resolution electron microscopy. The grain texture deduced from the high‐resolution structure images, which consist of groups of small coaxial Nb3Ge grains (A15 structure) which have one cubic axis [001] in common, is observed and analyzed using the high‐resolution structure images. The coaxial grains are related by a rotation of approximately ±30° around the [001] axis. Crystallites of Nb5Ge3 composition having either a D88 structure or D8m structure are distributed at random in the fabric and are coherent with the adjacent Nb3Ge grains. The statistical distribution of grain sizes of each compound is reported. The average grain size of Nb5Ge3 compounds is smaller than half the average size of the Nb3Ge grains.

In 〈100〉 cross‐sectional high‐resolution electron microscopy of the GaAs/AlAs heterointerface, images were formed only with chemically sensitive (200) and transmitted beams. The atomic configuration of the GaAs/AlAs interface can be characterized by the variation of (200) fringes at atomic resolutions. The large difference in the (200) fringe intensity between GaAs and AlAs layers greatly improves the visibility at the interface and relaxed the restriction on sample thickness. It is also shown that this technique is effective in observing the heterointerface of close compositions such as GaAs/AlGaAs.

InP/SiO2 interfaces have been studied by high resolution electron microscopy in cross section, by ellipsometry, and by x‐ray photoelectron spectroscopy. The roughness of the interface is shown to vary from 10 to 100 A peak to peak depending on the InP surface treatment prior to SiO2 desposition, and some evidence is found for a small amount of native oxide and P segregation at the interface. Thermal oxide grown on InP at 350 °C is shown to consist of two separate layers, an inner one of 30–70 A thickness and probably composition InPO4, and an outer one of 60‐A thickness and probably composition In2O3.

The new edition of this practical microscopy guide includes additional material on high-resolution images of periodic structures and associated techniques. It provides both a view of the fundamental principles of electron microscopy and detailed practical information needed to record the images. Various theoretical results are summarized and practical examples given. A considerable fraction of the book has also been set aside for practical information on setting up and using an electron microscope. Applications in materials science, mineralogy, the biology of radiation-sensitive specimens, semiconductor physics and solid-state chemistry are all described for research workers in these fields.