Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

Visionen der Medizinphysik

The results of the basic solution of the V1000 coolant transient benchmark obtained by means of the coupled code system DYN3D/ATHLET are compared to a variation calculation, where the coolant mixing is simulated using the CFD code CFX-5.

Der postgraduale Masterstudiengang "Medical Radiation Sciences" in Dresden

Technisches Seminar, DESY Zeuthen, 13.03.2007 Zeuthen

A three-dimensional hexagonal dynamic benchmark describing the ejection of a peripheral control rod in a VVER-440 core with neutron kinetics and simple adiabatic Doppler feedback. The initially critical reactor experiences a power excursion without any reactor scram. Nodal solutions are compared to a reference solution obtained with the fine mesh diffusion code CRONOS2.

WP1: Development of PET/CT for oncology

In-beam PET for radiotherapy monitoring

Quasi-Particle Model for the EOS - critical point imaginary μ

QCD Equation of State in a Quasi-Particle Perspective

Lattice QCD Based Equation of State - within a Quasi-Particle Perspective

There is a growing interest in graphite nanostructures since the discovery of exotic quantum properties of and the evidence for a field effect in few-layer-graphene (FLG) [1]. A promising method to produce mechanically stable and electrically isolated graphite nanostuctures is focused ion beam (FIB) implantation into diamond and subsequent annealing [2].
Graphite nanostructures with dimensions down to 100 nm, i.e. wires and electrodes including contact pads, which enable Hall and field effect measurements are produced by 30 keV Ga+ FIB implantation in a (100)- and (111)-oriented diamond surface followed by a subsequent annealing in the temperature range from 600° to 1500°C in vacuum. The structural quality and the electrical properties of the graphite nanostructures are investigated in dependence on the preparation conditions by means of AFM, SEM and electrical measuring techniques.
[1] K. S. Novoselov et al. Science 306, 666 (2004) and Nature 438, 197 (2005)
[2] A. M. Zaitsev and I. A. Dobrinet, phys. stat. sol. (a) 203, R35 (2006)

Renormalisation - from classical theory to quantum electrodynamics

In-Medium Hadronic Observables: Impact of Four-Quark Condensates

Four-Quark condensates in QCD Sum Rules for Nucleons and Mesons

Gluon Radiation of Heavy Quarks in Deconfined Matter

The continuous scaling down of the dimensions of Cu interconnect structures in microelectronics requires ultra thin barriers against Cu diffusion. Typically 10 nm thin films of pure, binary and ternary nitrides of refractory metals as Ta, TaN, TaSiN, WN are investigated to prevent effectively the Cu diffusion into the substrates. X-ray diffraction, depth profile analysis by glow discharge optical emission spectrometry (GD-OES), Auger electron spectrometry (AES) and Rutherford backscattering (RBS) and electron microscopy are used to correlate results of microstructure and phase characterization with diffusion phenomena [1-3].
The degradation of the barrier performance after annealing was controlled by depth profile analysis using GD-OES [4]. For each barrier composition a critical temperature was found above which a significant Cu concentration in the substrate occurred in the GD-OES signal. Apart from the Cu diffusion, also the onset of barrier material diffusion towards the surface could be traced by GD-OES. At GD-OES depth profiling of laterally inhomogeneous layers containing conducting as well as non conducting parts it became clear that focusing and defocusing effects of the sputtering ions exist.
Essential properties of these barrier layers, as electrical and thermal conductivity and resistivity against oxidation, are optimized by variation of the chemical composition. Phase formation and transformation or diffusion also depends strongly on the initial distribution of elements in the layer system. Therefore, an accurate quantification of the element concentration is needed for reliable production and thorough investigation. However, all applied methods have special advantages, disadvantages and limitations. With RBS, e.g., it is impossible to determine N and the layers must be deposited on C, but RBS delivers absolute concentrations without calibration. AES has an excellent lateral and depth resolution, but suffers from preferential sputtering and matrix effects and needs, as GD-OES, standard material for calibration. Therefore, only the combination of all could solve this requirement successfully.
[1] N. Mattern, M. Hecker, D. Fischer, C. Wenzel, N. Schell, W. Matz, H. Engelmann, E. Zschech, Microelectronics Reliability 40, 1765 (2000)
[2] M. Hecker, D. Fischer, V. Hoffmann, H.-J. Engelmann, A. Voss, N. Mattern, C. Wenzel, C. Vogt, E. Zschech, Thin Solid Films, 414, 2, 184 (2002)
[3] R. Huebner, M. Hecker, N. Mattern, V. Hoffmann, K. Wetzig, C. Wenger, H.-J. Engelmann, C. Wenzel, E. Zschech, J.W. Bartha , Thin Solid Films, 437, 248 (2003)
[4] V. Hoffmann, R. Dorka, L. Wilken, V.D. Hodoroaba, K. Wetzig, Surface and Interface Analysis 35, 7, 575 (2003)

A method of proceeding the elements of the system matrix for iterative reconstruction of PET data

Der Rossendorfer Freie-Elektronen Laser

Die Ionenstrahlsynthese mittels Fokussierten Ionenstrahl (FIB) wird am Beispiel des Kobalt-Disilizides erläutert und demonstriert sowie Anwendungen aufgezeigt.
Weitere FIB Applikationen im Bereich der Nano-Technologie, wie das Vorstrukturieren (Templating), die Ga-Implantation und das selektive anisitrope nasschemiche Ätzen als auch die Metallorganische CVD mit dem FIB werden diskutiert.

The flash lamp processing for Group IV semiconductors is discussed.

Das Verfahren zur Blitzlampen-Temperung im msec-Bereich für die SiC-Si-Heteroepitaxie wird vorgestellt.

Es wird ein Überblick über Innovationen im Institut FWI bei der Silizium-basierten Lichtemission und der Blitzlampen-Temperung gegeben.

An overview about silicon-based light emission from ion-implanted materials is given.

The EPOS – ELBE positron source, a positron annihilation multifacility project in Dresden, is presented.

Fabrication and evaluation of efficient light emitters comprising nanocluster-rich SiO2 layers

The effect of electric field generated by the application of surface acoustic waves on photoluminescence (PL) of silicon nanocrystals embedded in SiO2 films is studied. It is shown that the application of electric field results in an increase in the intensity of nanocrystal PL, the increase amounting to 10% at a field amplitude of 6 kV cm(-1). The results are discussed within the frame of the self-trapped exciton model.

In this talk an overview will be presented regarding the influence of ion irradiation effects and treatments on the formation of silicon-based light emission structures and devices. After a short overview to the complete field-as to my knowledge- we will concentrate on two activities performed at the FZR during the last years, (i) Blue-violet (400 nm) light emitters basing on Metal-Oxide-Silicon capacitors, and, (ii) Infrared (~1µm) light emitters basing on pn-junctions. Both approaches use ion beam processing as a key doping technique of advanced semiconductor technologies. For the first case we employed implantation of group IV ions (C, Si, Ge, Sn) into thermally silicon dioxide layers followed by an appropriate annealing step leading to electroluminescence effects with a power efficiency/external quantum efficiency of ~0.5/10 %. This preparation leads to the formation of semiconductor nanoclusters in the oxide matrix; the luminescence itself is related to defects. Comparing to other oxide production techniques like sputtering or evaporation it is shown that such high electroluminescence values are only possible on the base of ion beam processing, i.e. the combination of nanocluster synthesis and beam-induced energy deposition. For the second case we will demonstrate that appropriate boron implantation and annealing steps can lead to pn-junctions with two electroluminescence bands from bound excitons at 1.065 eV and around 0.95 eV. This effect needs local oversaturation of boron –which, of course, is only possible by ion implantation- leading to nanoclusters which produce the necessary doping and strain induced disturbances to the band structure.

Coolant mixing is an important mitigative mechanism against reactivity accidents caused by local boron dilution. Experiments on coolant mixing were carried out at three different test facilities representing three different reactor types. These are the ROCOM test facility modelling a German KONVOI-type reactor, the Vattenfall test facility being a model of a Westinghouse three-loop PWR and the Gidropress test facility modelling a VVER-1000 PWR. The scenario of the start-up of the first main coolant pump was investigated in all three facilities.
The experiments were accompanied by velocity measurements in the downcomer for the same scenario in the ROCOM and the Vattenfall test facilities. A similar flow structure was found in these measurements in both cases. A maximum of the velocity is measured at the opposite side in regard to the position of the loop with the starting-up pump whilst a recirculation area was found just below this inlet nozzle in both facilities.
The analysis of the slug mixing experiments showed also comparable flow behaviour. In accordance with the velocity measurements, the first part of the deboration is also found on the opposite side. In this region, the maximum deboration is measured in all three cases. These maximum values are in the same order of magnitude for nearly identical initial slug volumes.

Deep level defects in He-implanted n-6H-SiC studied by deep level transient spectroscopy

A lecture is given about slow positron implantation spectroscopy as a tool to characterize vacancy-type damage in ion-implanted 6H-SiC

The epitaxial 3C-SiC formation at the SiO2/Si interface by C+ Implantation into SiO2 and subsequent annealing is studied.

The mechanism of efficient light emission in boron implanted silicon diodes is discussed.

The temperature dependence of efficient silicon light-emitting diodes prepared by ion implantation is investigated.

The investigation of insulation debris generation, transport and sedimentation becomes more important with regard to reactor safety research for PWR and BWR, when considering the long-term behavior of emergency core coolant systems during all types of loss of coolant accidents (LOCA). The insulation debris released near the break during a LOCA incident consists of a mixture of disparate particle population that varies with size, shape, consistency and other properties. Some fractions of the released insulation debris can be transported into the reactor sump, where it may perturb/impinge on the emergency core cooling systems.
Open questions of generic interest are for example the particle load on strainers and corresponding pressure drop, the sedimentation of the insulation debris in a water pool, its possible re-suspension and transport in the sump water flow. A joint research project on such questions is being performed in cooperation with Institute of Process Technology, Process Automation and Measuring Technology (IPM) Zittau. The project deals with the experimental investigation and the development of CFD models for the description of particle transport phenomena in coolant flow. While the experiments are performed at the IPM-Zittau, the theoretical work is concentrated at Forschungszentrum Dresden-Rossendorf.
In the paper the basic concepts for CFD modeling are described and feasibility studies including the conceptual design of the experiments are presented.

A thermal model for flash lamp annealing of 3C-SiC/Si multilayer systems is developed.

An abstract is not available, please contact the author.

The way how to fabricate ultra-shallow junctions by plasma doping and flash lamp annealing is demonstrated.

Advanced Thermal Processing of Semiconducting Materials using Flash Lamp Annealing is Discussed.

An abstract is not available, please contact the authors.

An abstract is not available, please contact the authors.

The optical and microstructural properties of doubly implanted SiO2 layers fabicated combined Ge-Si implantation are investigated.

An abstract is not available, please contact the authors.

The nucleation control in FLASiC assisted short time liquid phase epitaxy by melt modification is studied.

The ion beam assisted formation of Ge nanocrystals in Ta2O5 films is studied.

Profiles of excess vacancies in silicon produced by ion implantation are studied by TEM.

E1/E2 an Z1/Z2 deep level defects in n-type 6H silicon carbide induced by electron irradiation and He implantation are studied.

EPOS – an intense positron beam project at the Research Center Rossendorf is presented

The design of a mono-energetic positron source for positron lifetime measurements at the radiation source ELBE is presented.

Gettering effects in CZ-type Silicon are investigated with SIMS

Effects of ion beam induced excess vacancies in silicon are discussed.

Investigation of defects induced by ion implantation of noble gases in yttria-stabilized zirconia

Microarrays of miniaturized silicon-based light sources: fabrication and use

Microstructural characterization of 3C-SiC thin films epitaxially formed by the flash lamp process (FLASIC)

In the present work, positron annihilation spectroscopy (PAS) is employed for microstructure investigations of various ultra fine grained (UFG) metals (Cu, Ni, Fe) prepared by severe plastic deformation (SPD), namely high-pressure torsion (HPT) and equal channel angular pressing (ECAP): Generally, UFG metals prepared using both the techniques exhibit two kinds of defects introduced by SPD: dislocations and small microvoids. The size of the microvoids is determined from the PAS data. Significantly larger microvoids are found in HPT deformed Fe and Ni compared to HPT deformed Cu. The microstructure of UFG Cu prepared by HPT and ECAP is compared and the spatial distribution of defects in UFG Cu samples is characterized. In addition, the mircrostructure of a pure UFG Cu prepared by HPT and HPT deformed Cu+Al2O3 nanocomposite (GlidCop) is compared.

Our aim in the present work was to investigate changes of the defect structure of bulk niobium induced by hydrogen loading. The evolution of the microstructure with increasing hydrogen concentration was studied by x-ray diffraction and two complementary techniques of positron annihilation spectroscopies (PAS), namely positron lifetime spectroscopy and slow positron implantation spectroscopy with the measurement of the Doppler broadening, in defect-free Nb (99.9%) and Nb containing a remarkable number of dislocations. These samples were electrochemically loaded with hydrogen up to xH=0.06 [H/Nb], i.e. in the alpha-phase region, and it was found that the defect density increases with hydrogen concentration in both Nb samples. This means that hydrogen-induced defects are created in the Nb samples. A comparison of PAS results with theoretical calculations revealed that vacancy-hydrogen complexes are introduced into the samples due to hydrogen loading. Most probably these are vacancies surrounded by 4 hydrogen atoms.

In the present work, positron annihilation spectroscopy (PAS) is employed for microstructure investigations of various ultra fine grained (UFG) metals (Cu, Ni, Fe) prepared by severe plastic deformation (SPD), namely high-pressure torsion (HPT) and equal channel angular pressing (ECAP): Generally, UFG metals prepared using both the techniques exhibit two kinds of defects introduced by SPD: dislocations and small microvoids. The size of the microvoids is determined from the PAS data. Significantly larger microvoids are found in HPT deformed Fe and Ni compared to HPT deformed Cu. The microstructure of UFG Cu prepared by HPT and ECAP is compared and the spatial distribution of defects in UFG Cu samples is characterized. In addition, the mircrostructure of a pure UFG Cu prepared by HPT and HPT deformed Cu+Al2O3 nanocomposite (GlidCop) is compared.

The photoluminescence of Er doped SiO2 films embedded Si nanoclusters is investigated. These clusters are fabricated by dual ion implantation and annealing.

A UHV device with a base pressure of p<10^-9 mbar was connected to the ECR ion source of the Forschungszentrum Rossendorf for improved calorimetric measurements of the retention of the potential energy of highly charged ions. The chemical state of the target surface is controlled by AES using LEED optics. With a clean silicon and gold surface prepared by sputtering using Ar-ions, the retained energy of Ar^q+ (q = 1 up to 9) ions was determined at kinetic energies between q*60 eV and q*200 eV . By extrapolation to zero kinetic energy, the retained fraction of the potential energy is obtained, which is related to the full potential energy given by the ionization potentials. The potential energy retention coefficient results as (0.8 up to 0.9) +- 0.2 and decreases weakly with increasing charge state. This is about three times larger than earlier results with contaminated copper surfaces.

Deep level defects in He-implanted n-6H-SiC are studied by deep level transient spectroscopy.

Density functional theory (DFT) calculations in combination with the polarizable continuum model (PCM) are a very useful method for obtaining the structure of actinide complexes in aqueous solution. The accuracy in energy, however, is often not sufficient to find a definite answer on whether ligands are coordinated in monodentate or bidentate fashion [1], pinpointing the limitations of working solely with theoretical calculations. Extended X-ray absorption fine structure (EXAFS) spectroscopy is a powerful experimental method for the determination of structures of aqueous complexes; the limitation is, however, a relatively poor distal resolution and often no information on the spatial orientation, making the resolution of co-existing species difficult. Finally, thermodynamic calculations also do not always provide accurate information.
Therefore, we combined all three methods, DFT, EXAFS, and thermodynamic speciation, to study the speciation and structure of actinide complexes in aqueous solution. We will show examples of uranyl(VI) ligation towards water, carbonate, and sulfate. We will also address the formation of polymeric complexes.

For the safety assessment of geological disposal of spent nuclear fuels, to predict and prevent migration of uranium in the geo-sphere is very important. Uranium can take oxidation states IV, V, and VI in aqueous solution. Its solubility differ several orders of magnitude depending on its oxidation state, but also depends strongly on pH and Eh of the solution and concentrations of co-existing organic/inorganic ligands. In this study, quantum chemical methods (MP2, CASPT2) were used to estimate the redox potential of the U(VI)/U(V) couple and the result was compared with experimental data. Similarly, An(VI)/An(V) redox potentials were also calculated for An = Np, Pu, and Am, and the importance of multi-configurational calculations and the role of spin-orbit effect were discussed.
Uranium may coordinate with various organic/inorganic ligands, and this is also a determining factor of the redox potential. We studied the complexation of uranium(VI) with several inorganic ligands (sulfate, carbonate, etc.) by DFT calculations and also by electrochemistry experiments. The structures of uranium complexes were characterized using EXAFS (extended X-ray absorption fine structure) spectroscopy at the Rossendorf Beamline, European Synchrotron Radiation Facility, in Grenoble, France. DFT and EXAFS were found to provide complementary structural information.

Rutherford Backscattering Spectrometry ( RBS) and Elastic Recoil Detection Analysis (ERDA) are well established techniques for quantitative thin film and surface analysis. The advantage of these methods consists in the simple physics they are basing on, namely the stopping of energetic ions in matter and the binary scattering of at the Coulomb potential of atomic nuclei.
In particular RBS with He ions is widely used at many small accelerators utilizing standard surface barrier or implanted silicon detectors with typical depth resolution values of 12 keV, which provides a depth resolution in the order of 10 nm.
The increasing importance of ultra-thin layers for novel technologies demands quantitative analysis techniques with a depth resolution of atomic monolayers, which can be obtained for RBS and ERDA by magnetic spectrometers only.
We operate at the 3 MV Tandetron accelerator a magnetic spectrometer consisting of an UHV scattering chamber and a simple magnet with circular field boundaries (Browne-Buechner spectrometer). Since in many cases of high resolution IBA the samples must be prepared in situ in UHV, the chamber with a base vacuum of 4x10-10 mbar is equipped with an Ar ion sputter gun and two OMICRON EFM3 low rate e-beam evaporators for in situ layer deposition.
A RHEED system is used to check the surface reconstruction and monitor the layer growth. Samples are transferred, together with a BN heater, to the precision 5-axes channelling goniometer . The magnet with a mean radius of 0.65 m is mounted vertically and can be positioned either at 35.5° or 144.5°. The backward position offers the advantage of a high mass resolution, but the Rutherford cross sections are a factor of about 100 lower than at the forward angle, which is the preferred position if kinematically possible.
Using a two-dimensional position sensitive focal plane detector the transversal position provides the possibility for kinematical corrections since the transversal focusing of the magnet is small. A multiple-pad PSD with a pitch of 4 mm is adequate.
This spectrometer is described, recent applications are discussed and as well as he influence of charge state transitions of ions on the obtainable depth resolution will be demonstrated.

The fundamentals of and recent results on depth profiling of defects in materials by means of a slow positron beam are reported.

6H-SiC surfaces after ion implantation and annealing are characterized by AFM.

The prototype of the new flash lamp apparatus is discussed and compared with the old equipment. First experiences and results are reported.

Es wird beschrieben, wie eine Datenbank für Betriebswerte eines Teilchenbeschleunigers aufgebaut wurde. Der Schwerpunkt der Betrachtungen liegt dabei auf der Theorie zum Aufbau einer solchen Datenbank.

Das Ziel der Diplomarbeit war, auf Basis eines 32-Bit Mikrocontrollers wesentliche Teile der Signalverarbeitung eines Rotorvoltmeters von analoger Schaltungstechnik in eine digitale Verarbeitung zu überführen. Mit diesem Schritt kann das am Institut für Ionenstrahlphysik und Materialforschung des FZR eingesetzte Rotorvoltmeter eines Van-de-Graaff-Ionenbeschleunigers in seiner Anwendung wesentlich verbessert werden. Erwartet werden neben der einfacheren Parametrierung und der erhöhten Flexibilität des Gerätes vor allem auch eine Erhöhung der Stabilität im Betrieb durch den Wegfall von Drifterscheinungen analoger Schaltungstechnik.

Das Ziel der Diplomarbeit war, auf Basis eines 32-Bit Mikrocontrollers wesentliche Teile der Signalverarbeitung eines Rotorvoltmeters von analoger Schaltungstechnik in eine digitale Verarbeitung zu überführen. Mit diesem Schritt kann das am Institut für Ionenstrahlphysik und Materialforschung des FZR eingesetzte Rotorvoltmeter eines Van-de-Graaff-Ionenbeschleunigers in seiner Anwendung wesentlich verbessert werden. Erwartet werden neben der einfacheren Parametrierung und der erhöhten Flexibilität des Gerätes vor allem auch eine Erhöhung der Stabilität im Betrieb durch den Wegfall von Drifterscheinungen analoger Schaltungstechnik.

Dipole-strength distributions in the nuclides 98Mo and 100Mo up to the neutron-separation energies have been studied in photon-scattering experiments at the superconducting electron accelerator ELBE of the Forschungszentrum Dresden-Rossendorf. In order to determine the dipole-strength distribution up to the neutron emission threshold statistical methods were developed for the analysis of the measured spectra. The measured spectra of scattered photons were corrected for detector response and atomic background by simulations using the code GEANT3. Simulations of gamma-ray cascades were performed in order to correct the intensities of ground-state transitions for feeding from high-lying levels and to determine their branching ratios. The photoabsorption cross sections obtained for 98Mo and 100Mo from the present (gamma,gamma) experiments are combined with (gamma,n) data from literature resulting in a photoabsorption cross section covering the full range from 4 to about 15 MeV of interest for nuclear astrophysics network calculations. Novel information about the low-energy tail of the Giant Dipole Resonance and the energy spreading of its strength is derived. The photoabsorption cross sections deduced from the present photon-scattering experiments are compared with existing data from neutron capture and 3He induced reactions.

Positron annihilation spectroscopy is used to analyse implantation defects in 6H-SiC.

In dem Vortrag werden die neuen Ergebnisse auf dem Gebiet der Cr- bzw. Ni-Implantation in Permalloy vorgestellt. Darüber hinaus wird über erste Ergebnisse der Bestrahlung von FeAl-Legierungen berichtet.

We present a study of the early stage of ripple formation on Ge(001) surfaces irradiated by a 1 keV Xe+ ion beam at room temperature and near-normal incidence. A combination of a grazing incidence x-ray scattering technique and atomic force microscopy allowed us to observe a variation of the symmetry of the surface nanopattern upon increase of the ion fluence. The isotropic dot pattern formed during the first minutes of sputtering evolves into an anisotropic ripple pattern for longer sputtering time. These results provide a new basis for further steps in the theoretical description of the morphology evolution during ion beam sputtering.

Star-shaped molecules based on a phloroglucinol core with three oligobenzoate arms are powerful mesogens, that can be combined to columnar liquid crystalline materials and to soft organic crystals. The structural properties of such modern materials exhibit polymorphism at two different length scales. On the molecular level, the mesogens are highly flexible molecules with a large variety of almost isoenergetic conformers of different propensity towards a regular stacking in the bulk phase. On the supramolecular level, polymorphic structures occur, which comprise different liquid crystalline phases with anisotropic columnar order and soft crystals with a more isotropic three-dimensional ordering. For the smallest mesogen the present experimental structure data and computational results give evidence that the two forms of polymorphism are linked. Columnar liquid crystals form from a low-symmetry, folded conformer, which already accounts for the nano-segregation of the planar aromatic centre and the flexible aliphatic chain parts of the mesogen, whereas the soft, more isotropic crystals are grown from the C3-symmetric, star-shaped conformer. Molecular dynamics simulations confirm the stability of each structure at room temperature.

A DC photocathode gun is part of the injector of the Energy Recovery Linac Prototype (ERLP) presently being built at Daresbury Laboratory. A buncher is required for the ERLP downstream of the photocathode gun to decrease the relatively long bunches (20-30ps) from the GaAs cathode. Three different single-cell cavity designs were investigated: the Cornell buncher, the ELBE buncher and an EU cavity without Higher Order Mode (HOM) dampers. The properties of these cavities were studied with the computer codes CSTs Microwave Studio and ASTRA. The fundamental frequency and field pattern of each buncher was investigated in Microwave Studio. The EU cavity was scaled from 500MHz to the required frequency for the buncher of 1.3GHz. As the anticipated kinetic energy of the electron beam after the gun is about 350keV a particle tracking code including the space charge forces is mandatory to study the effect of the different buncher cavity designs on the beam dynamics. The particle tracking code ASTRA was used to study the performance of the bunchers for a variety of beam parameters. From these investigations it was found that the three bunchers produce very similar effects on the particle bunch.

The impact of high energy Ga ion beams focused to diameters below 100 nm on antimony (Sb) substrates offers a new approach for the formation of pure Sb nanowires. In contrast to several well-known processes for bottom–up fabrication of one-dimensional nanostructures, for this process neither additional temperature treatment nor any additional material component is needed. Initially, the resulting nanostructures are completely amorphous and show very homogeneous diameters in the range of 20 nm. Lengths up to several microns can be achieved. Annealing at temperatures around 150 °C leads to re-crystallization of these nanowires.