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Freiberg, Germany

Richter D.,Max Planck Institute for Evolutionary Anthropology | Richter D.,University of Bayreuth | Krbetschek M.,TU Bergakademie Freiberg | Krbetschek M.,Freiberg Instruments GmbH
Journal of Human Evolution | Year: 2015

Thermoluminescence (TL) data are presented for eight samples of heated flint collected at the archaeological site of Schöningen 13/I-1 (Cycle I), for which a Holsteinian age is suggested by palynology of stratigraphically similar positions within a cyclic sedimentological model for the Quaternary sequence of Schöningen. Although the fire responsible for the zeroing of the TL-signal cannot be unequivocally attributed to human activities, any time difference between a natural fire and the human occupation is negligible for a site of this antiquity. The weighted mean age of 321±16ka places the last heating of the flints nominally in the age range of Marine Isotope Stages (MIS) 10 to 8. By inference this data would suggest an attribution of the Holsteinian to MIS 9 and may also serve as a maximum age estimate for the spear site of Schöningen 13/II-4 (Cycle II). Considering the chronometric data available and following an alternative sedimentological model the age of these two sites at Schöningen can be considered as belonging to the same climatic cycle. This suggests an attribution to MIS 9, and by inference provides an age estimate of 337-300ka for the oldest spears in human history. © 2015 Elsevier Ltd.

Agency: Cordis | Branch: FP7 | Program: CP | Phase: ICT-2013.3.3 | Award Amount: 11.05M | Year: 2013

SEA4KET (Semiconductor Equipment Assessment for Key Enabling Technologies) is an IP proposal taking the consequent step from equipment R&D to equipment assessment experiments. The strategic objective is to effectively combine resources and expertise in a joint assessment of novel equipment for key enabling technologies to foster and accelerate the successful transfer of novel European equipment into the world-wide market.\nSEA4KET builds on the proven principle established in previous European SEA programs and projects: to take novel, innovative and promising equipment that has left the R&D phase into a joint assessment activity this bridges the well-known gap between the phase of having an engineered tool available and finding the first user and finally success in the market for it.\nWhile proven principles from previous SEA activities are kept, SEA4KET takes them to the new field of assessing equipment for Key Enabling Technologies: SEA4KET concentrates on process and metrology systems for important enablers of future technologies: 450 mm wafer equipment, SiC material and 3D processing. The proposal comprises 15 sub-projects each dedicated to a specific equipment. The assessment activities were to a lesser extent chosen by high S&T excellence, but by their expected chance on the market.\nWhile leading R&D institutes are active in each assessment experiment to support individual final developments, several cross-cut R&D activities were identified (and combined in a dedicated sub-project) that are relevant to multiple assessments. Training material will be provided and workshops will be organized, to support and strengthen the individual dissemination activities.\nSEA4KET will significantly strengthen the European equipment and material industry for the emerging market for Key Enabling Technologies in a sustainable way by combining advanced R&D with equipment assessment involving users, institutes and equipment suppliers with specific benefit for SME suppliers.

Walter D.,Fraunhofer Institute for Solar Energy Systems | Walter D.,Institute for Solar Energy Research Hamelin | Rosenits P.,Fraunhofer Institute for Solar Energy Systems | Berger B.,TU Bergakademie Freiberg | And 3 more authors.
Progress in Photovoltaics: Research and Applications | Year: 2014

The effective minority carrier lifetimes on epitaxial silicon thin-film material have been measured successfully using two independent microwave-detected photoconductivity decay setups. Both measurement setups are found to be equally suited to determine the minority carrier lifetime of crystalline silicon thin-film (cSiTF) material. The different measurement conditions to which the sample under investigation is exposed are critically analyzed by both simulations and measurements on a large number of lifetime samples. No systematic deviation between the lifetime results from different measurement setups could be observed, underlining the accuracy of the determined lifetime value. Subsequently, a method to separate the epitaxial bulk lifetime and the total recombination velocity, consisting of front surface and interface recombination between the epitaxial layer and the substrate, is presented. The method, based on different thicknesses of the epitaxial layer, is applied to all batches of this investigation. Each batch consists of samples with the same material quality but different epitaxial layer thicknesses whereas different batches differ in their material quality. In addition, the same method is also successfully applied on individual cSiTF samples. From the results, it can be concluded that the limiting factor of the effective minority carrier lifetime for the investigated solar-grade cSiTF material is the elevated recombination velocity at the interface between epitaxial layer and the substrate compared with microelectronic-grade material. In contrast, the samples cannot be classified into different material qualities by their epitaxial bulk lifetimes. Even on multicrystalline substrate, solar-grade material can exhibit high epitaxial bulk lifetimes comparable to microelectronic-grade material. Copyright © 2012 John Wiley & Sons, Ltd. The effective carrier lifetime of crystalline silicon thin-film material has been measured on a wide range of different material qualities using two independent microwave-detected photoconductivity decay setups. No systematic deviation between the two measurement setups could be observed. Through a variation of the epitaxial layer thickness, the recombination in the interface region between the layer and the underlying substrate has been identified to be the limiting factor of the effective lifetimes. Copyright © 2012 John Wiley & Sons, Ltd.

Schuler N.,Freiberg Instruments GmbH | Berger B.,Freiberg Instruments GmbH | Blum A.,Sinton Instruments | Dornich K.,Freiberg Instruments GmbH | Niklas J.R.,Freiberg Instruments GmbH
Energy Procedia | Year: 2013

The iron density is one crucial parameter to verify the quality of the material. Brick measurements enable to check the material quality right at the beginning of the production line. This paper presents contact less high resolution inline topographic measurements of the iron density in multicrystalline silicon bricks by MDP (microwave detected photoconductivity). The measurement procedure is fully automatic and takes less than 5 min a brick. The data obtained were compared to QSSPC (quasi steady state photoconductivity) measurements, however, with a loss in spatial resolution. Furthermore, passivated wafers were prepared from the bricks after the measurements and investigated individually. The consistency of all the data is remarkable. © 2013 The Authors.

Berger B.,TU Bergakademie Freiberg | Schuler N.,Freiberg Instruments GmbH | Anger S.,Freiberg Instruments GmbH | Grundig-Wendrock B.,Solar World Innovations GmbH | And 2 more authors.
Physica Status Solidi (A) Applications and Materials Science | Year: 2011

The contactless electrical characterization techniques MDP and MD-PICTS will be presented in this paper. Both methods are predestined for defect investigation in a variety of semiconductors. Due to a so far not reached sensitivity, major advantages of MDP are its high spatial resolution and its measurement speed, which allows for two dimensional inline measurements at production speed. Furthermore a versatile numerical tool for simulations of electrical properties of a semiconductor as a function of defect parameters was developed. MD-PICTS is a contactless temperature dependent measurement which allows the determination of activation energies of trap levels in the material. To demonstrate the abilities of both methods, measurements conducted at different semiconductor materials, e.g. silicon, silicon carbide, gallium arsenide and indium phosphide, will be presented exemplarily. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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