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In this study the structural and morphological properties of perylene films deposited on different substrates have been investigated. The film properties have been studied by employing a range of techniques including atomic force microscopy, x-ray diffraction, and drop shape analysis for the determination of the surface free energy. For films deposited on top of Al2O3, the perylene molecules have a fiber texture ordering perpendicular to the substrate, while for films deposited on top of a Au(111) layer, only for thicker films above 400nm were diffraction peaks observed. The different growths of perylene on top of these substrates are attributed to the different strengths of the molecule-substrate interaction.

The growth of perylene films on an amorphous oxide bottom layer is investigated. The perylene films show clear spiral growth and formation of screw dislocations. As a function of deposition rate and film thickness the densities of screw dislocations, grains as well as the roughness and the lateral correlation length are determined from AFM images. The evolution of microstrain as calculated from an XRD peak profile analysis corresponds to the dislocation density. The simultaneous decrease of grain density and dislocation density with film thickness is explained by considering the overgrowth of grains due to loss of dislocations acting as growth spirals. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 3.5 μm AFM images of 700 nm perylene film. Left: topography. Right: edge enhanced, showing steps and spiral growth. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Comparative structural analyses of a crystallized, 60 nm thick silicon film deposited on quartz substrate were performed using high resolution transmission electron microscopy (HRTEM) and Raman spectroscopy (RS). Both methods suggest high degree of crystallization of the film. The material of the film consists of crystalline grains with sizes up to 20 nm (HRTEM) and the mean size of the grains is ∼4 nm (RS). HRTEM results suggest large scatter of the crystal orientations of the grains. The existence of boundary defects between grains grouped in large agglomerates was also detected by HRTEM. RS analyses indicate large compressive strain in the system and the existence of high pressure Si phases in the material of the film.