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Nanometer-sized structures, surfaces and sub-surface phenomena have played an enormous role in science and technological applications and represent a driving-force of current interdisciplinary science. Recent developments include the atomic-scale characterization of nanoparticles, molecular reactions at surfaces, magnetism at the atomic scale, photoelectric characterization of nanostructures as well as two-dimensional solids. Research and development of smart nanostructured materials governed by their surface properties is a rapidly growing field. The main challenge is to develop an accurate and robust electronic structure description. The density of surface-related trap states is analyzed by transient UV photoconductivity and temperature-dependent admittance spectroscopy. An advanced application of thin films on shaped substrates is the deposition of catalytic layers on hollow glass microspheres for hydrogen storage controlled exothermal hydrolytic release. Surface properties of thin films including dissolution and corrosion, fouling resistance, and hydrophilicity/hydrophobicity are explored to improve materials response in biological environments and medicine. Trends in surface biofunctionalization routes based on vacuum techniques, together with advances in surface analysis of biomaterials, are discussed. Pioneering advances in the application of X-ray nanodiffraction of thin film cross-sections for characterizing nanostructure and local strain including in-situ experiments during nanoindentation are described. Precise measurements and control of plasma properties are important for fundamental investigations and the development of next generation plasma-based technologies. Critical control parameters are the flux and energy distribution of incident ions at reactive surfaces; it is also crucial to control the dynamics of electrons initiating non-equilibrium chemical reactions. The most promising approach involves the exploitation of complementary advantages in direct measurements combined with specifically designed numerical simulations. Exciting new developments in vacuum science and technology have focused on forward-looking and next generation standards and sensors that take advantage of photonics based measurements. These measurements are inherently fast, frequency based, easily transferrable to sensors based on photonics and hold promise of being disruptive and transformative. Realization of Pascal, the SI unit for pressure, a cold-atom trap based ultra-high and extreme high vacuum (UHV and XHV) standard, dynamic pressure measurements and a photonic based thermometer are three key examples that are presented.

Nano-topography formation on material surfaces gains increasing interest in sensor, biomedical, optical, tribological applications by the wide options of introducing functionalities to the surface. While top-down structuring processes are not useable for large surfaces, bottom-up techniques, utilizing even material properties for targeted nanostructure formation control, become highly valuable. Self-assembling, fractal-like nano- and microtopography formed by bottom-up processes (physical vapor deposition techniques, magnetron sputtering, pulsed laser deposition) on polymers are presented in this work. Wrinkling effects are due to high stresses in the deposited thin films of different inorganic coating materials – titanium and titanium nitride in the current work – with high adhesion on the polymer substrates (polycarbonate, polyimide, polyamide, thermoplastic polyurethane). The feature size of the nano-hills and vermicular-like structures in the size between 10 nm and 100 μm distance and up to 300 nm height is controlled by the mechanical properties in the formed compound material.

The morphology of V 2 O 5 low-friction coatings on MgO (001) substrates synthesized by unbalanced reactive magnetron sputtering was investigated using atomic force microscopy. Analyzing the height–height correlation function, the evolution of the surface roughness parameters root mean square roughness (rms), lateral correlation length, and the Hurst parameter were determined. Studying samples of V 2 O 5 grown at temperatures from 25 °C to 300 °C, a transition from amorphous to crystalline growth at 80 °C was observed. The rms roughness increased from 0.7 nm at 26 °C to 21 nm at 300 °C. Furthermore, a method to quantitatively determine friction coefficients via friction force microscopy was applied. The surface contact forces were calculated via the cantilever's spring constants determined using the Sader method. At scan speeds of 1.25 μm/s and 3.13 μm/s, friction coefficients of 0.60 ± 0.02 and 0.63 ± 0.01, respectively, have been obtained.

Surface planarization and masked ion-beam structuring (MIBS) of high-Tc superconducting (HTS) YBa2Cu3O7-δ (YBCO) thin films grown by pulsed-laser deposition (PLD) method is reported. Chemical–mechanical polishing, plasma etching, and oxygen annealing of YBCO films strongly reduce the particulate density (~ 10–2 ×) and surface roughness (~ 10–1 ×) of as-grown PLD layers. The resistivity, critical temperature Tc ≈ 90 K and critical current density Jc (77 K) > 1 MA/cm2 of films are not deteriorated by the planarization procedure. The YBCO films are modified and patterned by irradiation with He+ ions of 75 keV energy. Superconducting tracks patterned by MIBS without removal of HTS material and, for comparison, by wet-chemical etching show same Tc and Jc(T) values. Different micro- and nano-patterns are produced in parallel on planarized films. The size of irradiated pattern depends on the mask employed for beam shaping and features smaller than 70 nm are achieved.

The epitaxial orientations of highly crystalline para-sexiphenyl (C 36 H 26 ) films on mica (001) surfaces are investigated by selected area electron diffraction (SAED) and transmission electron microscopy (TEM). Films at the early growth stage (growth time 26 s) and at an advanced growth stage (growth time 10 min) are studied. Films at the early growth stage exhibit only three-dimensional islands with an average size of 60×30×10 nm 3 , whereas films at an advanced growth stage consist of long oriented nano-fibres with a needle-like morphology. We identified three different types of epitaxial relations between the mica (001) substrate and the sexiphenyl crystallites, which are the same in both growth stages. Moreover, within a single island as well as within a single fibre crystalline domains with these three epitaxial orientations are observed. At the advanced growth stage, these domains are aligned antiparallel or perpendicular to the fibre axes; the typical size of the domains is 20 nm.

A two-temperature process has been applied to grow 80-nm Si 0.7 Ge 0.3 films on Si(001) by molecular-beam epitaxy (MBE). The first 30 nm were deposited at a reduced temperature of only 150–200°C (low-temperature stage). The subsequent growth was performed at 550°C, the temperature range conventionally applied for SiGe MBE. Using atomic-force microscopy, we observed that the misfit dislocation network introduced during sample heating after the low-temperature (LT) stage guides the arrangement of {105}-faceted pyramid-like islands. In the case of a very narrow dislocation network — induced by ion-assisted growth during the LT stage — a checkerboard array of {105}-faceted pits and pyramids evolves with a ‘lattice constant’ of approximately 200 nm.

In this work, Si + ions generated by the electron-beam evaporator are employed to influence strain and morphology of MBE-grown SiGe layers on Si (100) substrates. Strain relaxation of SiGe layers and modified surface morphology are attained by ion bombardment at reduced growth temperature. A study on the influence of ion energy (0–1000 eV) and density on both degree of relaxation and surface morphology is performed. Regular misfit-dislocation networks and a specific surface morphology are observed when the in situ ion bombardment at reduced temperatures leads to a degree of relaxation around 25%. This surface morphology shows uniform shallow pyramids ordered in directions which provide a template favourable for nanomagnets and other opto- and nanoelectronic applications.