Thin film materials

Coercivity of Thin-Film Media. The coercivity ia a magnetic material is an important parameter for appHcations but it is difficult to understand its physical background. It can be varied from nearly zero to more than 2000 kA/m ia a variety of materials. For thin-film recording media, values of more than 250 kA / m have been reported. First of all the coercivity is an extrinsic parameter and is strongly iafluenced by the microstmctural properties of the layer such as crystal size and shape, composition, and texture. These properties are directly related to the preparation conditions. Material choice and chemical inborn ogeneties are responsible for the Af of a material and this is also an influencing parameter of the final In crystalline material, the crystalline anisotropy field plays an important role. It is difficult to discriminate between all these parameters and to understand the coercivity origin ia the different thin-film materials ia detail. 

StiU another method used to produce PV cells is provided by thin-fiLm technologies. Thin films ate made by depositing semiconductor materials on a sohd substrate such as glass or metal sheet. Among the wide variety of thin-fiLm materials under development ate amorphous siUcon, polycrystaUine sUicon, copper indium diselenide, and cadmium teUuride. Additionally, development of multijunction thin-film PV cells is being explored. These cells use multiple layers of thin-film sUicon alloys or other semiconductors tailored to respond to specific portions of the light spectmm. 

Since the 1950s XRF has been used extensively for the analysis of solids, powders, and liquids. The technique was extended to analyze thin-film materials in the 1970s. XRF can be used routinely for the simultaneous determination of elemental composition and thickness of thin films. The technique is nondesuuctive, rapid, precise, and potentially very accurate. The results are in good agreement with other elemental analysis techniques including wet chemical, electron-beam excitation techniques, etc. 

Allen, T. H., et al., Enhanced Optical Thin-Film Materials, ... 

Electrocatalytic activity of supported metal particles has been investigated on surfaces prepared in an ultrahigh vacuum (UHV) molecular beam epitaxy system (DCA Instruments) modified to allow high throughput (parallel) synthesis of thin-film materials [Guerin and Hayden, 2006]. The system is shown in Fig. 16.1, and consisted of two physical vapor deposition (PVD) chambers, a sputtering chamber, and a surface characterization chamber (CC), all interconnected by a transfer chamber (TC). The entire system was maintained at UHV, with a base pressure of 10 °mbar. Sample access was achieved through a load lock, and samples could be transferred... 

NCu was calculated for 55 boundaries from four quantitative X-ray maps, and the probability distribution is shown in Figure 5.26. The mean coverage of this distribution is 2.2 atoms/nm2, and these data illustrate the feasibility of measuring segregation by X-ray mapping in the AEM in the case of fine-grained, thin film materials. 

Scott, G.D. Optical constants of thin film materials. J. opt. Soc. America... 

Shioya, Y., Ikeue, K., Ogawa, M., and Anpo, M. (2003) Synthesis of transparent Ti-containing mesoporous silica thin film materials and their unique photocatalytic activity for the reduction of C02 with H20. Applied Catalysis A General, 254 (2), 251-259. 

The primary methodologies for forming thin-film materials with atomic level control are molecular beam epitaxy (MBE) [4-9], vapor phase epitaxy (VPE) [10-12], and a number of derivative vacuum based techniques [13]. These methods depend on controlling the flux of reactants and the temperature of the substrate and reactants. 

Banger, K. K. Cowen, J. E. Hepp, A. F. 2001. Synthesis and characterization of the first liquid single-source precursors for the deposition of ternary chalcopyrite (CuInS2) thin film materials. Chem. Mater. 13 3827-3829. 

Selective Etching of Common Thin Film Materials... 

In this artide, we review the new field of combinatorial materials science. We describe in detail our particular materials exploration approach that we call the continuous compositional spread (CCS) approach. This CCS approach allows the synthesis and characterization of a major fraction of a ternary or pseudo-ternary phase spread in about 24 hours. We compare the CCS approach with other schemes for rapid materials investigations. We also provide an example of the successful application of the CCS approach in the discovery of a new high dielectric constant thin-film material, an amorphous zirconium tin titanate, aZTT. New combinatorial approaches to materials research can allow us to do studies that would not have been possible using conventional techniques. 

Systematized Search for a New High-s Thin-film Material 10.3.r... 

J 0.3 Systematized Search fora New High-e Thin-film Material 1161... 

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