TY  - JOUR
A1  - Wang, G.
A1  - Nespurek, S.
A1  - Rakusan, J.
A1  - Karaskova, M.
A1  - Schauer, F.
A1  - Brehmer, Ludwig
T1  - Polarized electrolumineseence from bilayer structures
N2  - The photoalignment ability of poly[methyl(phenyl)silylene] (PMPSi) films makes it possible to use them as hole- transporting substrates for the preparation of organic oriented films. A PMPSi layer prepared by spin coating was irradiated, after drying, with linearly polarized UV light. Then, water-soluble hydroxyaluminium phthalocyaninesulfonate [Al(OH)Pc(SO3Na)(1-2)] was deposited by casting. The cell ITO/PMPSi/AI(OH)Pc(SO3Na)(1-2)/Al showed non-linear current- voltage characteristics. For applied voltages higher than 10 V, polarized electroluminescence was observed. Its spectral characteristic consisted of two peaks with maxima at about 320 and 700 nm; their polarized anisotropies R-EL = Phi(parallel to) / Phi(perpendicular to) were ca. 15 and 0.5, respectively
Y1  - 2004
SN  - 1022-1360
ER  - 
TY  - JOUR
A1  - Smertenko, P. S.
A1  - Dimitriev, O. P.
A1  - Schrader, Sigurd
A1  - Brehmer, Ludwig
T1  - Doping of polyaniline by transition metal salts : current-voltage characteristics of the ITO/polymer film/metal heterostructures
N2  - Films of emeraldine base of polyaniline (PAni) doped by various transition metal salts have been prepared, and current-voltage characteristics of the indium-tin oxide (ITO)/PAni film/metal electrode heterostructures were investigated. It was found that the electrical characteristics of the heterostructures are greatly affected by the dopant used and the metal electrode used. Different dopants resulted in different current anomalies with asymmetric current-voltage characteristics. Depending on the dopant used, the exponential and power law of the current behavior can be distinguished. Depending on the metal electrode used, two different regimes of current passing have been found at low applied voltages, namely, a nearly ohmic regime for the indium electrode, and a diode regime for the aluminum electrode. The diode regime was found to accompany by a positive charge accumulation in the film near the film/metal interface, which creates a built-in potential in the film. The amount of positive charges accumulated at the interface and therefore the value of the built-in potential can be reversibly increased or reduced by successive runs of the applied voltage in the forward or reverse direction, respectively. (C) 2004 Elsevier B.V. All rights reserved
Y1  - 2004
SN  - 0379-6779
ER  - 
TY  - JOUR
A1  - Bochenkov, V.
A1  - Karageorgiev, Peter
A1  - Brehmer, Ludwig
A1  - Sergeev, G. B.
T1  - Quenched growth of nanostructured lead thin films on insulating substrates
N2  - Lead island films were obtained via vacuum vapor deposition on glass and ceramic substrates at 80 K. Electrical conductance was measured during vapor condensation and further annealing of the film up to room temperature. The resistance behavior during film formation and atomic force microscopy of annealed films were used as information sources about their structure. A model for the quenched growth, based on ballistic aggregation theory, was proposed. The nanostructure, responsible for chemiresistive properties of thin lead films and the mechanism of sensor response are discussed. (C) 2003 Elsevier B.V. All rights reserved
Y1  - 2004
SN  - 0040-6090
ER  -