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41.
Wolfram Witte Daniel Abou‐Ras Karsten Albe Gottfried H. Bauer Frank Bertram Christian Boit Rudolf Brüggemann Jürgen Christen Jens Dietrich Axel Eicke Dimitrios Hariskos Matthias Maiberg Roland Mainz Max Meessen Mathias Müller Oliver Neumann Thomas Orgis Stefan Paetel Johan Pohl Humberto Rodriguez‐Alvarez Roland Scheer Hans‐Werner Schock Thomas Unold Alfons Weber Michael Powalla 《Progress in Photovoltaics: Research and Applications》2015,23(6):717-733
The gallium gradient in Cu(In,Ga)Se2 (CIGS) layers, which forms during the two industrially relevant deposition routes, the sequential and co‐evaporation processes, plays a key role in the device performance of CIGS thin‐film modules. In this contribution, we present a comprehensive study on the formation, nature, and consequences of gallium gradients in CIGS solar cells. The formation of gallium gradients is analyzed in real time during a rapid selenization process by in situ X‐ray measurements. In addition, the gallium grading of a CIGS layer grown with an in‐line co‐evaporation process is analyzed by means of depth profiling with mass spectrometry. This gallium gradient of a real solar cell served as input data for device simulations. Depth‐dependent occurrence of lateral inhomogeneities on the µm scale in CIGS deposited by the co‐evaporation process was investigated by highly spatially resolved luminescence measurements on etched CIGS samples, which revealed a dependence of the optical bandgap, the quasi‐Fermi level splitting, transition levels, and the vertical gallium gradient. Transmission electron microscopy analyses of CIGS cross‐sections point to a difference in gallium content in the near surface region of neighboring grains. Migration barriers for a copper‐vacancy‐mediated indium and gallium diffusion in CuInSe2 and CuGaSe2 were calculated using density functional theory. The migration barrier for the InCu antisite in CuGaSe2 is significantly lower compared with the GaCu antisite in CuInSe2, which is in accordance with the experimentally observed Ga gradients in CIGS layers grown by co‐evaporation and selenization processes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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J. Beger H.-J. Binte L. Brunne R. Neumann 《Advanced Synthesis \u0026amp; Catalysis》1992,334(3):269-277
Synthesis of 4-Alkoxy-2-hydroxyphenyl Ketoximes as Reagents for Metal Extraction The C-Acylation (Friedel-Crafts reaction) of resorcinol with aluminium chloride, the monoetherification in 4-position of the resulting 2,4-dihydroxyphenylketones, and the preparation of oximes ( 8, 9, 10, 11 ) from this ketones were investigated. The compounds obtained are characterized by elemental analysis, and the i.r., u.v. and 1H-n.m.r. spectra are discussed. Solubility data of some oximes are determined in water, octane and toluene. The extraction properties for copper-(II)-and iron-(III)-ions are measured by isotope methods in relation to the extragent structure, the extraction time and the pH-range. 相似文献
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Neumann Sebastian Asad Amjad Kasper Tom Schwarze Rüdiger 《Metallurgical and Materials Transactions B》2019,50(5):2334-2342
Metallurgical and Materials Transactions B - In the paper, two different cleaning strategies for nonmetallic inclusions in steel melts, active filtration and reactive cleaning, are examined in a... 相似文献
45.
J. Duan J. Liu H. Yao D. Mo Y. Chen L. Zhang M. Hou R. Neumann 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(16):2567-2570
Cobalt nanowires with diameter 75 nm were synthesized in ion track-etched membranes by electrochemical deposition. Scanning electron microscopy displays cylindrical wires with smooth and homogeneous contours. X-ray diffraction studies indicate that the wires possess a face centered cubic structure and a preferred growth orientation along the [1 1 0] direction. The wires exhibit magnetic anisotropy, which is observed and is ascribed to shape anisotropy. The optical extinction spectrum shows a band which probably originates from a surface plasmon resonance. 相似文献
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用多种快重离子辐照高定向石墨(HOPG),借助扫描隧道显微镜(STM)系统地研究了表面及体内缺陷,结果表明,离子在表面及解理面上都形成了小丘状的缺陷,且在表面较容易形成,可以用非连续损伤径迹结构来对其进行解释。 相似文献
48.
J. Tillmans P. Neumann und H. Will 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1918,35(12):497-498
Ohne Zusammenfassung 相似文献
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