NANO SURFACE TECHNOLOGY AND GENERAL LABORATORY SERVICES
Picture above: AFM recording of a V2A metal surface equipped with nanoparticles, to control the height and distribution of the applied structure. Image size 4x6 thousandths of a millimeter
General explanation of nano technology:
The collective term nanotechnology, often also nanotechnology (nanoancient greek dwarf), is based on the same magnitude of the nanoparticles from singleatom up to a structure size out of 100 nanometers (nm): A nanometer is one billionth of a meter (10 E−9 m). This order of magnitude denotes a border area in which the surface properties play an increasingly important role compared to the volume properties of the materials and increasingly quantum physical Effects must be considered. In nanotechnology, length scales are used, on which the size in particular determines the properties of an object. One speaks of “size-induced functionalities”.
The term is used today to describe the relevant research in the cluster, Semiconductor- and surface physics, the Surfaces- and other areas of Chemistry as well as in parts of the mechanical engineering and food technology (nano food) designated.
Nanomaterials already play an important role today. They are mostly produced chemically or by mechanical methods. Some of them are commercially available and used in commercial products, others are important model systems for physicochemical and materials science research.
Also important is the nanoelectronics. Their affiliation with nanotechnology is not seen uniformly in scientific and research-political practice. The effects and influence of the mostly artificially produced particles on the environment are unclear and unexplored in many areas.
A direction of development of nanotechnology can be seen as a continuation and expansion of microtechnology be viewed (top downapproach), but further miniaturization of micrometer structures usually requires completely unconventional new approaches. Chemistry in nanotechnology often follows the opposite approach: bottom up. Chemists typically working in molecular, i.e. Sub-nanometer dimensions work, build up larger nanoscale molecular compounds from a large number of individual molecular units.
AFM ATOMIC FORCE MICROSCOPE
SHOWS ATOMIC RESOLUTION
Picture made with a Nanosurf Mobile S AFM (Atomic Force Microscope) by Nobel Aerospace Ltd.
In a good scanning tunneling microscopy image of highly oriented pyrolytic graphite (HOPG) you will see a pattern consisting of white, gray and black spots. To interpret the graphite STM image correctly: the bright spots mean higher tunneling current and dark spots mean lower tunneling current.
2x2nm HOPG STM image, z-range 0.2nm
Out of the lattice model of graphite one can see that there are two different positions of the carbon atoms in the graphite crystal lattice (see e.g. RC Tatar et al. Phys Rev B 25 (1982) 4126).
One with a neighboring atom in the plane below (grey) and one without a neighbor in the lattice below (white). Consequently the electrical conductivity of the graphite surface varies locally slightly (different electronic density of states) so that the atoms without neighbors appear "higher" than the others (see e.g. I.P. Batra et al. Surf Sci 181 (1987) 126). This also causes the HOPG lattice constant between the bright 'hills' to have the higher value of 0.25nm than the nearest neighbor distance in the graphite lattice of 0.14nm.
