Crystal structure, thin films techniques

Starting with basic physical concepts and synthetic techniques, the book describes how molecules assemble into highly ordered structures as single crystals and thin films, with examples of characterization, morphology and properties. Special emphasis is placed on the importance of surfaces and interfaces. The final chapter gives a personal view on future possibilities in the field. 

As a probe of lattice vibrations, Raman spectroscopy is very sensitive to intrinsic crystal properties and extrinsic stimuli, especially in semiconductors. It may be employed to study crystal structure and quality, crystal orientation, optical interactions, chemical composition, phases, dopant concentration, surface and interface chemistry, and local temperatme or strain. As an optical technique, important sample information may be obtained rapidly and nondestructively with minimal sample preparation. Submicron lateral resolution is possible with the use of confo-cal lenses. These features have made it a vital tool for research labs studying semiconductor-based technologies. They also are increasingly important for the study of semiconductor NWs fabricated by both top-down and bottom-up approaches since many of the common characterization methods used with bulk crystals or thin films cannot be applied to NWs in a direct manner. 

During the last two decades a number of surface science techniques were developed that provided atomic level information on atomic or electronic surface structure as well as surface composition with ever improving spatial and time resolution [1]. LEED, XPS, AES, and SIMS have been routinely applied for surface characterization of single-crystal or thin film model catalysts used in the course for catalytic reaction studies. However, their drawback has been the need for a high vacuum working environment. To overcome this restriction, UHV compatible high pressure cells were developed [2,3] that combined capabilities to perform catalytic... 

In this paper, we review the determination of the shape and the structure of metal particles by electron microscopy as illustrated by examples of Pd clusters epitaxially oriented on oxide single crystals and thin films of MgO and ZnO. The metal-oxide interfaces are characterized by HRTEM profile-view imaging, numerical analysis of the images, and image simulations by the multi-slice technique. 

Transmission electron microscopy (TEM) can resolve features down to about 1 nm and allows the use of electron diffraction to characterize the structure. Since electrons must pass through the sample however, the technique is limited to thin films. One cryoelectron microscopic study of fatty-acid Langmuir films on vitrified water [13] showed faceted crystals. The application of TEM to Langmuir-Blodgett films is discussed in Chapter XV. 

Lincot D, Ortega-Borges R (1992) Chemical bath deposition of cadmium sulfide thin films. In situ growth and structural studies by Combined Quartz Crystal Microbalance and Electrochemical Impedance techniques. J Electrochem Soc 139 1880-1889... 

A naturally occurring chiral metal structure is a screw dislocation (Fig. 3.4),11 which is a chiral arrangement observed in metal crystals but never resolved and tested for enantioselective heterogeneous catalysis. A possible method of making chiral arrangements like screw dislocations is by the glancing angle deposition technique, which can produce chiral sculptured thin films.12... 

Two diacetylenes have been epitaxially polymerized as thin films in contact with alkali halide substrates. These films in contact with alkali halide substrates. These films consisted of highly oriented single crystals aligned along both <110> directions of the substrate. The structures of both poly(TCDU) and poly(DMDA) were modified by this technique and, in all cases, highly crystalline near-perfect films were achieved. 

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