Superlattice film

Two requirements should be satisfied in order to achieve the enhancement in strength of the superlattices modulation wavelength (X.) in the scale of nanometre and sharp interfaces between layers. There is an optimum for a superlattice film to achieve the maximum strength, as shown in Fig. 12 [100-102]. The strength of the superlattice film will de-... 

Schmitt J, Decher G, Dtessick WJ, Brandow SL, Geer RE, Shashidhar R, Calvert JM. Metal nanoparticle/polymer superlattice films fabrication and control of layer structure. Adv Mater 1997 9 61-65. 

Li YL, Hu SY, Tenne D, Soukiassian A, Schlom DG, Chen LQ, Xi XX, Choi KJ, Lorn CB, Saxena A, Lookman T, Jia QX (2007) Interfacial coherency and ferroelectricity of BaTi03/ SrTiOa superlattice films. Appl Phys Lett 91 252904... 

Fig. 14. Optical absorption coefficient a determined from photoconductivity for a-Si H/ a-SiNjj H superlattice film 1.2 /im thick with alternating layers of 1200 A a-Si H and 35 A...

For pSi superlattice multilayers of high quality, it is also possible to correlate the observed fringes in the low-order satellite peaks with the total number of periods in the pSi film (Buttard et al. 1998). This is viewed as strong evidence of lateral homogeneity of the entire superlattice film thickness overall. 

A number of other systems have been shown to be suitable for multilayer build-up by the ESA, like charged latex nanospheres [50,199,285-287] or metallo-supramolecular complexes [288-290]. ESA has also been combined with Langmuir-Blodgett transfer [291-294], and even superlattice films have been produced. 

Lvov, Y, Essler, F. and Decher, G., Combination of polycation/polyanion self-assembly and Langmuir-Blodgett transfer for the construction of superlattice films. JPhys Chem, 1993. 97 p. 13773-13777. 

Surface phase transformations and surfrice chemical reactions are followed by studying the time evolution of superlattice beams originating from monolayer or submonolayer films. See, for example. Chapters 8-10 in Low-EnergyYaj Hove et al. op cit.). 

Barnett, S. A., "Deposition and Mechanical Properties of Superlattice Thin Films, Rhysics of Thin Films, Vol. 17, Mechanic and Dielectric Rroperties, M. H. Francombe and J. L. Vossen, Eds., Academic Press, Inc., 1993, pp. 2-77. 

Generation of nanoparticles under Langmuir monolayers and within LB films arose from earlier efforts to form nanoparticles within reverse micelles, microemulsions, and vesicles [89]. Semiconductor nanoparticles formed in surfactant media have been explored as photocatalytic systems [90]. One motivation for placing nanoparticles within the organic matrix of a LB film is to construct a superlattice of nanoparticles such that the optical properties of the nanoparticles associated with quantum confinement are preserved. If mono-layers of capped nanoparticles are transferred, a nanoparticle superlattice can be con-... 

A smaller class of type II alloys of II-VI binaries also exists, including the (CdS) ,(ZnSe)i (CdS) ,(ZnTe)i (CdSe) ,(ZnSe)i (CdS) ,(CdTe)i-. (CdSe)x(CdTe)i i , and (CdS) c(ZnS)i i systems, which transform at some critical composition from the W to the ZB structure. Importantly, the transition temperatures are usually well below those required to attain a thermodynamically stable wurtzite form for the binary constituents (e.g., 700-800 °C for pure CdS and > 1,020 "C for pure ZnS). The type 11 pseudobinary CdxZni jcSe is of considerable interest in thin film form for the development of tandem solar cells as well as for the fabrication of superlattices and phosphor materials for monitors. The CdSe Tei-x alloy is one of the most investigated semiconductors in photoelectrochemical applications. 

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