Search Results - "Unold, T."

Oxygen deficiency and Sn doping of amorphous Ga2O3 by Heinemann, M. D., Berry, J., Teeter, G., Unold, T., Ginley, D.

“…The potential of effectively n-type doping Ga2O3 considering its large band gap has made it an attractive target for integration into transistors and solar…”
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Measurement of charge carrier mobilities in thin films on metal substrates by reflection time resolved terahertz spectroscopy by Hempel, H, Unold, T, Eichberger, R

“…We show that charge carrier mobilities can be measured by reflection time resolved THz spectroscopy (R-TRTS) even for thin films on metal contacts, such as…”
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Experimental indication for band gap widening of chalcopyrite solar cell absorbers after potassium fluoride treatment by Pistor, P., Greiner, D., Kaufmann, C. A., Brunken, S., Gorgoi, M., Steigert, A., Calvet, W., Lauermann, I., Klenk, R., Unold, T., Lux-Steiner, M.-C.

“…The implementation of potassium fluoride treatments as a doping and surface modification procedure in chalcopyrite absorber preparation has recently gained…”
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Phase-transition-driven growth of compound semiconductor crystals from ordered metastable nanorods by Mainz, R., Singh, A., Levcenko, S., Klaus, M., Genzel, C., Ryan, K. M., Unold, T.

“…In polycrystalline semiconductors, grain boundaries are often sites with prevalence for electron-hole recombination and various strategies have been followed…”
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Analysis of grain orientation and defects in Sb2Se3 solar cells fabricated by close-spaced sublimation by Krautmann, R., Spalatu, N., Gunder, R., Abou-Ras, D., Unold, T., Schorr, S., Krunks, M., Oja Acik, I.

“…•Seed layer deployment clearly improved performance of TiO2/Sb2Se3 solar cells.•Pole figures revealed seed layer enhanced texture of Sb2Se3 along [001]…”
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Evolution of opto-electronic properties during film formation of complex semiconductors by Heinemann, M. D., Mainz, R., Österle, F., Rodriguez-Alvarez, H., Greiner, D., Kaufmann, C. A., Unold, T.

“…Optical and electrical properties of complex semiconducting alloys like Cu(In,Ga)Se 2 (CIGS) are strongly influenced by the reaction pathways occurring during…”
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Effect of precursor stacking order and sulfurization temperature on compositional homogeneity of CZTS thin films by Olgar, M.A., Klaer, J., Mainz, R., Levcenco, S., Just, J., Bacaksiz, E., Unold, T.

“…In this study, Cu2ZnSnS4 (CZTS) absorber layers were grown by sequential deposition of metallic Cu, Zn, and Sn layers by DC magnetron sputtering on Mo coated…”
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Nonconventional (Non-Silicon-Based) Photovoltaic Materials by Unold, T, Schock, H.W

“…Although photovoltaic devices and modules made from crystalline silicon currently dominate the market, many efforts in developing photovoltaics involve the use…”
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Cliff-like conduction band offset and KCN-induced recombination barrier enhancement at the CdS/Cu2ZnSnS4 thin-film solar cell heterojunction by Bär, M., Schubert, B.-A., Marsen, B., Wilks, R. G., Pookpanratana, S., Blum, M., Krause, S., Unold, T., Yang, W., Weinhardt, L., Heske, C., Schock, H.-W.

“…The electronic structure of the CdS/Cu2ZnSnS4 (CZTS) heterojunction was investigated by direct and inverse photoemission. The effects of a KCN etch of the CZTS…”
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Native oxidation and Cu-poor surface structure of thin film Cu2ZnSnS4 solar cell absorbers by Bär, M., Schubert, B.-A., Marsen, B., Krause, S., Pookpanratana, S., Unold, T., Weinhardt, L., Heske, C., Schock, H.-W.

“…Air-exposed Cu2ZnSnS4 (“CZTS”) thin-film solar cell absorbers have been investigated by surface-sensitive x-ray photoelectron and x-ray-excited Auger electron…”
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The influence of Na on low temperature growth of CIGS thin film solar cells on polyimide substrates by Caballero, R., Kaufmann, C.A., Eisenbarth, T., Cancela, M., Hesse, R., Unold, T., Eicke, A., Klenk, R., Schock, H.W.

“…The objective of this work is to study the influence of Na on the properties of Cu(In,Ga)Se 2 (CIGS) absorber layers and finished solar cell devices on…”
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Photoluminescence study of solution-deposited Cu2BaSnS4 thin films by Levcenko, S., Teymur, B., Mitzi, D. B., Unold, T.

“…To experimentally identify the character of radiative transitions in trigonal Cu2BaSnS4, we conduct temperature and excitation intensity dependent…”
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Metal acetate based synthesis of small-sized Cu2ZnSnS4 nanocrystals: effect of injection temperature and synthesis time by Irkhina, A, Levcenko, S, Hinrichs, V, Plate, P, Unold, T

“…We report the colloidal synthesis of small-sized Cu2ZnSnS4 (CZTS) nanocrystals (NCs) via a hot-injection method using zinc and tin acetates in combination with…”
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Effect of Na presence during CuInSe2 growth on stacking fault annihilation and electronic properties by Stange, H., Brunken, S., Hempel, H., Rodriguez-Alvarez, H., Schäfer, N., Greiner, D., Scheu, A., Lauche, J., Kaufmann, C. A., Unold, T., Abou-Ras, D., Mainz, R.

“…While presence of Na is essential for the performance of high-efficiency Cu(In,Ga)Se2 thin film solar cells, the reasons why addition of Na by post-deposition…”
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Effect of sodium on material and device quality in low temperature deposited Cu(In,Ga)Se2 by Puttnins, S., Levcenco, S., Schwarzburg, K., Benndorf, G., Daume, F., Rahm, A., Braun, A., Grundmann, M., Unold, T

“…Sodium is known to play an important role for the performance optimization of Cu(In,Ga)Se2 (CIGSe) thin film solar cells, i.e. it is found to significantly…”
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Efficient CuInS2 solar cells by reactive magnetron sputtering by Unold, T., Sieber, I., Ellmer, K.

“…We demonstrate CuInS2 thin film solar cell device efficiencies larger than 10% by preparing the absorber layers by reactive magnetron sputtering from metallic…”
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Depth profiling of Cu(In,Ga)Se2 thin films grown at low temperatures by KAUFMANN, C. A, CABALLERO, R, UNOLD, T, HESSE, R, KLENK, R, SCHORR, S, NICHTERWITZ, M, SHOCK, H.-W

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Impact of KCN etching on the chemical and electronic surface structure of Cu2ZnSnS4 thin-film solar cell absorbers by Bär, M., Schubert, B.-A., Marsen, B., Krause, S., Pookpanratana, S., Unold, T., Weinhardt, L., Heske, C., Schock, H.-W.

“…The chemical and electronic surface structure of Cu2ZnSnS4 thin-film solar cell absorbers has been investigated by direct and inverse photoemission. Particular…”
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Influence of Na on Cu(In,Ga)Se2 solar cells grown on polyimide substrates at low temperature: Impact on the Cu(In,Ga)Se2/Mo interface by Caballero, R., Kaufmann, C. A., Eisenbarth, T., Grimm, A., Lauermann, I., Unold, T., Klenk, R., Schock, H. W.

“…There are still open questions regarding the nature of the positive effect of the presence of Na on the performance of Cu(In,Ga)Se2 based, chalcopyrite thin…”
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Nanometer-scale electronic and microstructural properties of grain boundaries in Cu(In,Ga)Se2 by SADEWASSER, S, ABOU-RAS, D, LI, W, MILLO, O, RISSOM, Th, ROSENWAKS, Y, SCHOCK, H.-W, SCHWARZMAN, A, UNOLD, T, AZULAY, D, BAIER, R, BALBERG, I, CAHEN, D, COHEN, S, GARTSMAN, K, GANESAN, K, KAVALAKKATT, J

“…Despite many recent research efforts, the influence of grain boundaries (GBs) on device properties of CuIn1-xGaxSe2 solar cells is still not fully understood…”
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