The assembly of colloidal semiconductive nanocrystals into highly ordered superlattices predicts novel structure‐related properties by design. However, those structure–property relationships, such as charge transport depending on the structure or even directions of the superlattice, have remained unrevealed so far. Here, electric transport measurements and X‐ray nanodiffraction are performed on self‐assembled lead sulfide nanocrystal superlattices to investigate direction‐dependent charge carrier transport in microscopic domains of these materials. By angular X‐ray cross‐correlation analysis, the structure and orientation of individual superlattices is determined, which are directly correlated with the electronic properties of the same microdomains. By that, strong evidence for the effect of superlattice crystallinity on the electric conductivity is found. Further, anisotropic charge transport in highly ordered monocrystalline domains is revealed, which is attributed to the dominant effect of shortest interparticle distance. This implies that transport anisotropy should be a general feature of weakly coupled nanocrystal superlattices.

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Mathematical modeling of the cell-material contact demands a thorough characterization of both the material surface and the cellular reaction. In earlier investigations we used stochastic material surfaces for this purpose. Also, other groups working on the same or similar subject used such stochastically structured material surfaces. In continuation of this work we now use fine-structured material surfaces with well-defined regular geometry because a stepwise and systematic variation of the structural parameters of geometrically defined surfaces makes it easier to find the characteristic parameters for modeling the cell-material interface. To begin with, we used grooves with rectangular profiles and cubic pillars. The grooves were etched in silicon by dry etching and then were sputter coated with 100 nm titanium. Arrays of cubic photo resist pillars with vertical side walls in different dimensions were obtained by a photolithographic process and were also sputter coated with 100 nm titanium. The samples were characterized by SEM and electrochemical methods. Human osteoblastic cells MG-63 (ATCC, LGC promochem, Manassas, USA) were cultured in Dulbecco's modified eagle medium with 10% fetal calf serum (FCS) at 37• C and 5% CO 2 . MG-63 cells grown on microstructures within 24 h were visualized by SEM. We observed that cells on the grooved surfaces grew along the grooves mainly adhering to the horizontal edges of the material surface, whereas on the pillar structures the cells lie on the top of the pillars and are well spread. But the direction of spreading on the pillars is also determined by the horizontal and vertical edges of the surface structure.

Ion beam etching has been successfully applied to InP using an Ar/O2-gas mixture. Varying angles of beam incidence resulted in different shapes of the etched profiles with the achievement even of undercutting. Good selectivity with respect to Novolak-type photoresists prevails at higher accelerating voltages.

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