A5013325251- Silicon and Solar Cell Technologies
- Crystallization and Solubility Studies
- Thin-Film Transistor Technologies
- X-ray Diffraction in Crystallography
- Integrated Circuits and Semiconductor Failure Analysis
- Silicon Carbide Semiconductor Technologies
- Semiconductor materials and interfaces
- Advanced Surface Polishing Techniques
- Photovoltaic System Optimization Techniques
- Semiconductor materials and devices
- Thermography and Photoacoustic Techniques
- GaN-based semiconductor devices and materials
- solar cell performance optimization
- Industrial Vision Systems and Defect Detection
- Concrete and Cement Materials Research
- Silicon Nanostructures and Photoluminescence
- Chalcogenide Semiconductor Thin Films
- Diamond and Carbon-based Materials Research
- Thermal properties of materials
- Chemical Thermodynamics and Molecular Structure
- 3D IC and TSV technologies
- Structural Analysis of Composite Materials
- Fuel Cells and Related Materials
- Phase-change materials and chalcogenides
- Photonic and Optical Devices
Technical University of Munich
2020-2023
Carl Zeiss (Germany)
2021
Fraunhofer Institute for Photonic Microsystems
2021
Industrial Solar (Germany)
2010-2018
SeaWorld Entertainment
2018
Mettler-Toledo (China)
2017
PVA TePla (Germany)
2015
Universität Trier
2011-2015
Bavarian Center for Applied Energy Research
2010
TU Bergakademie Freiberg
2007
The efficiency record of industrial type PERC solar cells exceeded 22% at the turn year 2015 to 2016. Our best screen-printed cell reached 22.04% while batch showed a very narrow distribution. A detailed electrical and optical loss analysis those high is carried out which enables further optimization strategic improvements. variety characterization data allows for recombination current density, resistance based on numerical device simulation, analytical calculations raytracing, respectively....
Abstract Background: The abuse of synthetic cannabinoids (SCs) as presumed legal alternative to cannabis poses a great risk public health. For economic reasons many laboratories use immunoassays (IAs) screen for these substances in urine. However, the structural diversity and high potency designer drugs places demands on IAs regarding cross-reactivity antibodies used detection limits. Methods: Two retrospective studies were carried out order evaluate capability two homogenous enzyme...
The residual shear stress and the defect distribution in single‐crystalline c ‐plane AlN wafers prepared from crystals which were grown by physical vapor transport are visualized scanning infrared depolarization (SIRD) compared to synchrotron white‐beam X‐ray topography (WB‐XRT) measurements. Although at lower resolution, SIRD images resemble seen WB‐XRT, provides an order of magnitude higher spatial resolution and, this case, enables discerning individual dislocations. For a wafer crystal...
Liposomes consisting of egg phosphatidylcholine were prepared by a thin-film hydration method followed sonication and used to investigate the percentage encapsulation four flavonoids (quercetin, rutin, isoscutellarein diglycoside). The lipid recovery flavonoid-to-lipid molar ratio measured using high-performance thin-layer chromatography/flame ionization detection UV-vis spectroscopy. Differential scanning calorimetry was study effect on phase transition temperature enthalpy main...
A detailed approach to evaluate the sub-surface damage of diamond wire-sawn monocrystalline silicon wafers relating sawing process is presented. Residual stresses, presence amorphous and microcracks are considered related wire velocity cutting ability. In particular, degree amorphization wafer surface analyzed, as it may affect etching performance (texturing) during solar cell manufacture. Raman spectroscopy Scanning Infrared Stress Explorer (SIREX) measurements used independently...
We report on electroluminescence (EL) imaging of organic photovoltaic cells and modules with poly(3-hexylthiophene)/[6,6]-phenyl C61 butyric acid methyl ester as semiconductor layer. The dominant EL emission is found in a spectral regime between 1200 1400 nm identified the radiative decay charge transfer complex formed polymer fullerene. Electroluminescence from pristine compounds either much weaker or completely absent. Overall, shown to give valuable information defects but also...
Solar cells made of upgraded metallurgical grade silicon (UMG-Si) feedstock material generally show an increased reverse current at a relatively low bias, which is thought to be disadvantageous for the use in solar modules. In used this study, flows through many soft breakdown sites recombination active defects. The onset voltage decreased primarily due net doping concentration wafer base UMG-Si wafers compared standard multicrystalline silicon. We attribute behavior enhancement electric...
The capacitance-voltage (CV) measurement is a precise and fast method to determine base-dopant concentrations of crystalline silicon solar cells. Since available equipment usually limited in its current output, the application CV analysis has been small-area cells research laboratories. We present an experimental setup that capable measuring curves with output up 2 A. Using this setup, we demonstrate applicability measurements large-area industrial for ranging between 6.0 × 10 <sup...
In addition to boron and oxygen, copper is also known cause light-induced degradation (LID) in silicon. We have demonstrated previously that LID can be prevented by depositing negative corona charge onto the wafer surfaces. Positively charged interstitial ions are proposed diffuse negatively surface consequently empty bulk of copper. this study, out-diffusion was confirmed chemical analysis near region negatively/positively silicon wafer. Furthermore, permanently removed etching copper-rich...
The removal of azo dyes is a critical issue in current textile industry wastewater treatment. In contemporary management, many structures that are direct contact with constructed concrete. this contribution, the Congo red from aqueous solutions by material surface hardened binder paste was studied multiple exposure experiments. Flat prisms made ordinary Portland cement (OPC) and ground granulated blast-furnace slag (GGBS) were stored different solutions. powdered these flat used as substrate...
High‐efficiency solar cell designs such as the passivated emitter and rear (PERC) raise quality requirements for silicon substrates, favoring monocrystalline materials. Seed‐cast quasi‐monocrystalline (qm‐Si) is a promising alternative Czochralski (Cz) Si with potential benefits of lower cost reduced energy footprint. However, purity crystalline qm‐Si not on par Cz‐Si, which can cause efficiency losses example in form light‐induced degradation (LID). In this contribution, we study LID...
Abstract Using idealised assumptions, the stress condition in semi infinite body of Hertzian contact region can be calculated for various geometries as a function surface pressure (normal force), friction (tangential force at surface) and residual stresses material. Equivalent formed from coordinate using hypotheses (distortion energy hypothesis, shear hypothesis alternating hypothesis). The effects friction, geometry on location magnitude equivalent appearing material have been...
We present a technique to measure the interstitial oxygen concentration in monocrystalline silicon directly on 180 μm industrial solar wafers using an appropriate measurement setup. This avoids material and time consuming fabrication of special thicker samples which are usually necessary for Fourier Transform Infrared Spectroscopy (FTIR) measurements silicon. compare data obtained from wafer results slices use FTIR method evaluate impact high temperature steps content wafers.