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Central to the use of Ge-Sb-Te based phase-change materials for data storage applications is their crystallization capability since it determines memory writing time. Although being intensively studied to identify intrinsic limits and develop strategies to enhance memory performance, the crystallization process in these materials is still not fully explored. Therefore, this study focuses on the determination of crystal growth dynamics in an epitaxial phase-change material thin film model system offering the advantage of high crystalline quality and application-relevant sizing. By introducing a method that combines time-resolved reflectivity measurements with high-resolution scanning transmission electron microscopy, crystal growth velocities upon fast cooling after single ns-laser pulse irradiation of the prototypical phase-change material Ge2Sb2Te5are determined. As a result, an increase in crystal growth velocity from 0.4 to 1.7 m/s with increasing laser fluence is observed with a maximum rate of 1.7 m/s as the upper detectable limit of the studied material.

A route toward a top‐down fabrication of non‐periodically arranged substrate‐bound metal nanostructure arrays using mask projection laser ablation is presented. In the first step phase masks featuring non‐periodic patterns are fabricated by laser lithography and subsequent ion‐beam etching. It is shown that the geometry of the diffraction mask projection laser ablation (DiMPLA) setup plays a crucial role for the ability to transfer non‐periodic phase mask structures into arrangement of nanodots. The latter nanostructures, in the present case derived from an ultrathin Au film on a sapphire substrate, consist non‐periodically arranged gold nanodots. These dots are exemplarily used as templates for the growth of sculptured thin films (STFs) by glancing‐angle deposition (GLAD).

Nano-sculptured thin films (STF) are prepared by the glancing angle deposition technique and take different forms of nano columnar structures. Varieties of STFs are investigated to find the optimum structure for biosensing based on the surface enhanced fluourescence (SEF). The highest amplification of fluorescent signal is found for Ag based STFs on fused silica giving an enhancement factor of x23°, where h=400nm, d=75nm, á=23o relative to Ag dense film using fluorescent dye Rhodamine 123. Based on this, a demonstration of monitoring of antibodies and even confirmation of successful immobilization of the receptors presented. Bound antibody to the thiol self assembly monolayer on sample surface is then quantified by means of the fluorescent signal. Upon excitation of the fluorophore by Hg source light, a CCD camera with a controlled exposure time detects the pattern of fluorescent antibody/E-coli bacteria colonies on the STF surface. A fiber optic holder attached to the microscope allowed quantitative measurement of the fluorescence spectrum on a microspot.

Germanium nanocolumns grown by glancing angle deposition on Si(100) substrates and prepatterned substrates comprising of SiO2nanospheres demonstrated an altered morphology that is greatly influenced by the substrate temperature (TS). Surface diffusion‐driven mass transport and increased adatom mobility at homologous temperatures TS/TM≈ 0.34 and 0.39 (TMmelting temperature of Ge) augmented fibrous‐columnar and intracolumnar growth, respectively. Further increment of the substrate temperature provoked column merging and column broadening. The degree of film crystallinity increased while TSincreased from 200 to 340 °C, shifting the preferential crystallite orientation from (111) to (220).

Eine physikalische Deposition unter den Bedingungen eines schräg einfallenden Partikelflusses und begrenzter Adatom‐Diffusion führt zu Schichten mit einer säulenartigen Mikrostruktur. Diese Säulen sind in Richtung der Partikelquelle orientiert. Eine zusätzliche Substratrotation kann genutzt werden, um diese Strukturen in unterschiedlicher Gestalt (senkrechte und geneigte Säulen, Zick‐Zack‐Strukturen, Schrauben, Spiralen) zu entwickeln. Mit der Deposition unter schrägem Partikeleinfall (GLAD) können poröse dünne Schichten von isolierenden, halbleitenden und metallischen Materialien konstruiert werden. In dieser Arbeit werden die physikalischen Grundlagen der GLAD‐Technologie vorgestellt, die Herstellung von Mikro‐ und Nano‐Struktruren unterschiedlichen Habitus auf nicht strukturierten und vorstrukturierten Substraten demonstriert und auf einige potentielle Anwendungen dieser neuen Depositionstechnologie hingewiesen.

High-energy oxygen ions were implanted with fluences from 2.5×1017up to 1.5×1018O+-ions/cm2into molybdenum at temperatures between −60°C and room temperature. Subsequent annealing processes were carried out at 500°C up to 60 min. The chemical composition was investigated using Rutherford backscattering spectrometry. The concentration distribution of the implanted oxygen is characterized by two kinds of profiles: gaussian profiles are observed, when the fluence is lower than the critical fluence required to form a buried molybdenum oxide layer, and a concentration plateau, when the fluence exceeds this critical concentration. Annealing reinforces the tendency to form a flat-topped distribution. Electron and X-ray diffraction studies show that the molybdenum oxide phase δ-MoO2is formed during annealing. Cross-sectional TEM studies of the as-implanted and annealed oxygen implanted molybdenum are presented. After implantation a buried amorphous layer between strongly damaged material could be found in the near surface region. With increasing annealing time different oxide precipitate morphologies and a buried molybdenum oxide layer covered by an amorphous layer is formed.

Polycrystalline titanium was implanted with nitrogen ions at energies from 30 to 60 keV and with doses from 1 × 1016 to 1.5 × 1018 N+-ions cm-2 at room temperature. The implanted titanium layers were investigated by high-voltage electron microscopy and transmission high-energy electron diffraction. The formation of titanium nitride, titanium carbonitride and titanium carbide phases were considered in relation to their dependence on nitrogen ion implantation dose. In the dose range from 1 × 1016 up to 1.5 × 1018 N+-ions cm-2 the cubic phase d-TiNx was formed. In the dose range between 1 to 2.5 × 1017 and 1.5 × 1018N+-ions cm-2 the tetragonal phase e-Ti2N was found in addition to the d-TiNx phase. The lattice structure of these titanium nitride phases is a function of the nitrogen ion implantation dose. Additionally, the presence of titanium carbonitrido TiCyOx and titanium carbide TiCy phases can be proved. The analysed titanium nitride, titanium carbUnitride and titanium carbide phases are represented in a state diagram as a function of implantation dose.

Growing highly crystalline nanowires over large substrate areas remains an ambiguous task nowadays. Herein, a time‐efficient and easy‐to‐handle bottom‐up approach is demonstrated that enables the self‐assembled growth of biaxially textured Ti thin films composed of single‐crystalline nanowires in a single‐deposition step. Ti thin films are deposited under highly oblique incidence angles by electron beam evaporation on amorphous substrates. Substrate temperature, angle of the incoming particle flux, and working pressure are varied to optimize the crystallinity in those films. Height‐resolved structure information of individual nanowires is provided by a transmission electron microscopy (TEM) nanobeam, high‐resolution TEM, and electron diffraction. Ti nanowires are polycrystalline at 77 K, whereas for ≥300 K, single‐crystalline nanowires are tendentially found. The Ti crystals grow along the thermodynamically favored c‐direction, but the nanowires’ tilt angle is determined by shadowing. Biaxially textured Ti thin films require a certain temperature range combined with highly oblique deposition angles, which is proved by X‐ray in‐plane pole figures. A general correlation between average activation energy for surface self‐diffusion and melting point of metals is given to estimate the significant influence of surface self‐diffusion on the evolution of obliquely deposited metal thin films. Herein, the formation of biaxially textured, columnar titanium thin films on amorphous substrates at different temperatures (77 K ≤ TSub≤ 873 K) is investigated. The Ti columns tend to grow as single crystallines. A relation is derived that allows to estimate the average adatom surface self‐diffusion length for a given substrate temperature.

Chemically synthesized YBa2Cu3Oxhas been characterized by scanning electron microscopy, energy dispersive X-ray analysis and high-voltage electron microscopy. The surface topography and the composition are strongly depended on time of sintering. Diffraction studies show the superconducting phase to crystallize in a orthorhombic, oxygen-deficient perovskite superstructure. Different phase transitions and the variation of the unit cell parameters were observed as function of temperature.

For many applications non‐periodic or uncommonly shaped phase masks are necessary to pattern structural features on the nanoscale. Highly efficient fabrication of non‐periodically arranged gold nanostructure arrays using interfering laser beams is demonstrated by Marisa Mäder et al. on pp. 2208–2211. The templates are generated by diffraction mask projection laser ablation of thin metal films. The metal nanodots are bound to the substrate, thus improving their mechanical stability, chemical inertness, and technological compliance. The well ordered nanodot arrangements are fast and easy to fabricate.

Silicon carbide layers grown by C60deposition on silicon (100) substrates at temperatures between 700°C and 870°C were investigated by optical microscopy (OM) as well as by scanning and transmission electron microscopy (SEM and TEM). The formation of extended cavities in the substrate surfaces, below the growing SiC layers, was observed. These cavities start to develop at the very beginning of SiC nucleation. The SiC layers bridging the cavities consist of columnar grains and contain open channels in between the grains. The epitaxial-oriented cubic fractions in the SiC layers increase with the elevation of the substrate temperature applied during C60deposition.