Ultrathin film characterization

Other excellent methods of phase identification include TEM and electron diffraction. These may be more useful for low-Z materials, ultrathin films, and for characterizing small areas, including individual grains. For multiphase films with incomplete texture, these methods and XRD are complementary, since in commonly used geometries, they probe atomic planes perpendicular and parallel to the thin film surface, respectively. 

Ultrathin films of CdS ranging in coverage from 25 to 200 ML were grown also by the previous method on Au substrates (of non-specified nature) and were characterized by quantitative Raman resonance [41], It was found that the electronic structure of the films in this coverage regime corresponds to that of bulk CdS. It was concluded also that ECALE does not involve growth by random precipitation of CdS onto the Au surface the thin deposited layers of the material were contiguous. 

The parameters K1/ K2/ and K3 are defined by the refractive indices of the crystal and sample and by the incidence angle [32]. If the sample has uniaxial symmetry, only two polarized spectra are necessary to characterize the orientation. If the optical axis is along the plane of the sample, such as for stretched polymer films, only the two s-polarized spectra are needed to determine kz and kx. These are then used to calculate a dichroic ratio or a P2) value with Equation (25) (replacing absorbance with absorption index). In contrast, a uniaxial sample with its optical axis perpendicular to the crystal surface requires the acquisition of spectra with both p- and s-polarizations, but the Z- and X-axes are now equivalent. This approach was used, through dichroic ratio measurements, to monitor the orientation of polymer chains at various depths during the drying of latex [33]. This type of symmetry is often encountered in non-polymeric samples, for instance, in ultrathin films of lipids or self-assembled monolayers. 

Kera S, Yamane H, Honda H, Fukagawa H, Okudaira KK, Ueno N (2004) Photoelectron fine structures of uppermost valence band for well-characterized CLAl-phthalocyanine ultrathin film UPS and MAES study. Surf Sci 566 571... 

Lu C, Donch I, Nolte M, Fery A (2006) Au nanoparticle-based multilayer ultrathin films with covalently linked nanostructures spraying layer-by-layer assembly and mechanical property characterization. Chem Mater 18 6204-6210... 

Y. Shimazaki, M. Mitsuishi, S. Ito, M. Yamamoto, Preparation and Characterization of the Layer-by-Layer Deposited Ultrathin Film Based on the Charge-Transfer Interaction in Organic Solvents , Langmuir, 14,2768 (1998)... 

Ultraviolet Raman spectroscopy has emerged as a powerful technique for characterization of nanoscale materials, in particular, wide-bandgap semiconductors and dielectrics. The advantages of ultraviolet excitation for Raman measurements of ferroelectric thin films and heterostructures, such as reduced penetration depth and enhanced scattering intensity, are discussed. Recent results of application of ultraviolet Raman spectroscopy for studies of the lattice dynamics and phase transitions in nanoscale ferroelectric structures, such as superlattices based on BaTiOs, SrTiOs, and CaTiOs, as well as ultrathin films of BaTiOs and SrTi03 are reviewed. 

The electronic structure, morphology, and chemical reactivity of metal nanoclusters have attracted considerable attention due to their extensive technological importance. Chemical reactions and their catalytic relevance have been investigated on a variety of well-characterized, supported model catalysts prepared by vapor deposition of catalytically relevant metals onto ultrathin oxide films in ultrahigh vacuum conditions. Such ultrathin film supports are usually prepared by vaporizing a parent metal onto a refractory metal substrate in an oxygen atmosphere at a high temperature. These unique model systems are particularly well suited for surface-... 

Chance B 1991 Optical method Annu. Rev. Biophys. Biophys. Chem. 20 1-28 Granstrom M, Berggren M and Ingan s O 1995 Micrometer- and nanometer-sized polymeric light-emitting diodes Science 267 1479-81 Hanken D G and Com R M 1995 Variable index of refraction ultrathin films formed from self-assembled zirconium phosphonate multilayers Characterization by surface plasma resonance measurements and polarization/modulation FT-IR spectroscopy Anal. Chem. 67 3761-74... 

Franchina J. G., Lackowski W. M., Dermody D. L., Crooks R. M., Bergbreiter D. E., Sirkar K., Russell R. J., and Rishko M. V, Electrostatic immobilization of glucose oxidase in a weak acid, polyelectrolyte hyperbranched ultrathin film on gold Fabrication, characterization, and enzymatic activity, A a/. Chem., 71(15), 3133-3139,1999. 

Lvov Y, Decher G, Mohwald H. 1993. Assembly, structural characterization, and thermal behavior of layer by layer deposited ultrathin films of poly(vinyl sulfate) and poly (aUylamine). Langmuir 9 481 486. 

Li, F, Shan, C., Bu, X., Shen, Y, Yang, G., and Niu, L. (2008). Fabrication and electrochemical characterization of electrostatic assembly of polyelectrol3d e-functionalized ionic liquid and Prussian blue ultrathin films./ Electroanal. Chem, 616, pp. 1-6. 

Wegner, G. (1992). Ultrathin films of polymers Architecture, characterization, properties. Thin Solid Films 216, 105-116. 

V. P. Tolstoy, Ph.D. Thesis, Synthesis and IR Spectroscopic Characterization of Ultrathin Films on Metal Surfaces, Leningrad State Technological University, Leningrad, 1980. 

Chernyshova and Rao [558] snggested to characterize the MO and MP from IRRAS of ultrathin films on transparent substrates by fitting the DR calculated... 

The formation and characterization of ultrathin film formed by poly(3-amino-benzoic acid) (PABA) was carried out by Sriwichai et al. [55] using ESPR for the development of immunosensor to detect human immunoglobulin G. With the aid of simultaneous measurements of SPR and CV it has been become possible to calculate the thickness and dielectric properties of a polymeric film, allowing that immunosensor responses can be related to its surface morphology. Another ESPR biosensor also based on PABA was developed by Baba et al. [56] to detect adrenaline. The polymer acts as a specific reaction site for adrenaline, presenting different electrochemical and SPR responses to those for uric and ascorbic acids, which are major interferences of the catecholamine studied. The two techniques were used to evaluate the electrodeposition of PABA and to obtain the calibration curves and the detection limit was set to 100 pmol... 

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