A5002378588- Silicon and Solar Cell Technologies
- Silicon Carbide Semiconductor Technologies
- Semiconductor materials and devices
- Ion-surface interactions and analysis
- Integrated Circuits and Semiconductor Failure Analysis
- Thin-Film Transistor Technologies
- GaN-based semiconductor devices and materials
- Nanowire Synthesis and Applications
- Semiconductor materials and interfaces
- Silicon Nanostructures and Photoluminescence
- Metal and Thin Film Mechanics
- Semiconductor Quantum Structures and Devices
- Quantum Dots Synthesis And Properties
- Photonic Crystals and Applications
- Ga2O3 and related materials
- Block Copolymer Self-Assembly
- Electron and X-Ray Spectroscopy Techniques
- Diamond and Carbon-based Materials Research
- Nanofabrication and Lithography Techniques
- CCD and CMOS Imaging Sensors
- ZnO doping and properties
- Force Microscopy Techniques and Applications
- Advanced Electron Microscopy Techniques and Applications
- Chalcogenide Semiconductor Thin Films
- Image and Signal Denoising Methods
Paderborn University
2016-2025
University of Bonn
2013-2025
University of Augsburg
2001-2011
Augsburg University
1999-2011
TU Dortmund University
1987-1994
Czech Academy of Sciences, Institute of Physics
1989
It is shown that diamond nucleation on iridium buffer layers followed by an appropriate textured-growth step offers a viable way to realize single-crystal films. Bias-enhanced results in heteroepitaxial films with highly improved alignment. By subsequent step, the mosaicity can be further reduced for tilt as well twist sharp contrast former experiments using silicon substrates. Minimum values of 0.17° and 0.38° have been measured twist, respectively. Plan view transmission electron...
Abstract Image restoration via alternating direction method of multipliers (ADMM) has gained large interest within the last decade. Solving standard problems Gaussian and Poisson noise, set “Total Variation” (TV)-based regularizers proved to be efficient versatile. In few years, Generalized (TGV) approach combined TV different orders adaptively better suit local regions in image. This improved technique significantly. The solved staircase problem inherent first-order while keeping beneficial...
Abstract Block copolymer (BCP) self‐assembly (SA) can be exploited for next‐generation lithography the advanced nanopatterning of surfaces with versatile nanoscale features. To render BCP‐SA suitable creation tailored surface patterns, a fundamental understanding interfacial interactions is crucial. This progress report gives an overview on interplay BCP microscale film thickness modulation and microphase separation during BCP‐SA. Light shed role energies in both events. Microscale processes...
We investigate the impact of shell growth on carrier dynamics and exciton–phonon coupling in CdSe–CdS core–shell nanoplatelets with varying thickness. observe that recombination can be prolonged by more than one order magnitude, analyze results a global rate model as well simulations including strain excitonic effects. reveal type I band alignment hetero platelets is maintained at least up to three monolayers CdS, resulting approximately constant radiative rates. Hence, observed changes...
Abstract Dodecyl amine edge functionalized few-layer graphene oxide quantum dots were synthesized in good yields. The covalent functionalization was demonstrated with NMR and AFM-IR. resulting structure particle size measured AFM HRTEM. thermal stability of the compound investigated showed a up to 220 °C. modified excellent solubility various organic solvents, including ethers, methanol, toluene, n -hexane, heptane, xylene, dichloromethane toluene. toluene solution also proven by static...
Measurements in general are limited accuracy by the presence of noise. This also holds true for highly sophisticated scintillation-based CCD cameras, as they used medical applications, astronomy or transmission electron microscopy. Further, signals measured with pixelated detectors convolved inherent detector point spread function. The Poisson noise, arising from quantized nature beam electrons, gets correlated this convolution, which allows to reconstruct PSF based on Wiener–Khinchin...
Abstract Block copolymer (BCP) lithography is a versatile bottom‐up approach for the creation of regular nanoscale patterns on large surface areas. The pattern morphology evolving during microphase separation BCP strongly dependent polymer film thickness. Thus, wetting as well interfacial energies between and substrate determine behavior, however, complex interplay those effects not yet fully understood. In this work, model describing thickness dependence self‐assembly prepatterned surfaces...
The existence of anti-phase domains in cubic GaN grown on 3C-SiC/Si (001) substrates by plasma-assisted molecular beam epitaxy is reported. influence the substrate morphology studied with emphasis (APDs). nucleation governed APDs substrate, resulting equal plane orientation and same boundaries. presence independent layer thickness. Atomic force microscopy surface analysis indicates lateral growth anisotropy facets dependence APD orientation. This can be linked to Ga N face types {111}...
Block copolymer lithography for the nanopatterning of Au, Pt and TiO<sub>2</sub> surfaces is presented; by combining this technique with nanosphere lithography, we create hierarchical nanopores.
DNA origami nanostructures are versatile substrates for the controlled arrangement of molecular capture sites with nanometer precision and thus have many promising applications in single-molecule bioanalysis. Here, we investigate adsorption nanohole arrays which represent an important class biosensors may benefit from incorporation origami-based probes. Nanoholes well-defined diameter that enable single triangles fabricated Au films on Si wafers by nanosphere lithography. The efficiency...
Tuning Exciton–Phonon Interaction in CdSe Nanoplatelets.
Atomistic simulations on the silicon carbide precipitation in bulk employing both, classical potential and first-principles methods are presented. The calculations aim at a comprehensive, microscopic understanding of mechanism context controversial discussions literature. For quantum-mechanical treatment, basic processes assumed process calculated feasible systems small size. migration carbon...
A heterojunction field-effect transistor (HFET) was fabricated of nonpolar cubic AlGaN/GaN grown on Ar+ implanted 3C–SiC (001) by molecular beam epitaxy. The device shows a clear field effect at positive bias voltages with Vth=0.6 V. HFET output characteristics were calculated using ATLAS simulation program. electron channel the interface detected room temperature capacitance-voltage measurements.
Abstract We report the influence of {111} stacking faults on cathodoluminescence (CL) emission characteristics cubic GaN (c‐GaN) films and GaN/AlN multi‐quantum wells. Transmission electron microscopy (TEM) measurements indicate that (SFs) planes are predominant crystallographic defects in epitaxial films, which were grown 3C‐SiC/Si (001) substrates by plasma‐assisted molecular beam epitaxy. The correlation SFs luminescence output is evidenced with a CL setup integrated scanning TEM (STEM)....
Thin C60 films have been deposited on mica(001) substrates by thermal evaporation at substrate temperatures between room temperature and 200 °C a constant deposition rate. The influence of the growth C60-thin has systematically investigated x-ray diffraction. θ–2θ measurements (111) peaks show decrease full width half-maximum (FWHM) with increasing temperature, leading to minimum FWHM 0.15° for °C. Oriented an out-of-plane mosaic spread Δω=0.2° could be grown 150±25 It can shown that...