The European Physical Journal Applied Physics

Physics of Organic Materials and Devices

Evaluation of organic sub-monolayers by X-ray based measurements under gracing incident conditions

O. Werzera1, B. Stadlobera2, A. Haasea2, H.-G. Flescha1 and R. Resela1

Institute of Solid State Physics, Graz University of Technology, Graz, Austria

Institute of Nanostructured Materials and Photonics, Joanneum Research Forschungsgesellschaft mbH, Weiz, Austria


The structural investigations of model organic systems like pentacene on silicon oxide in the monolayer regime is very important for the basic understanding of initial nucleation process together with the electronic performance of transistor devices. A method for the evaluation of the island formation and layer closing of the first monolayer is introduced. The method is based on specular X-ray reflectivity and diffuse scattering and reveal integral information on the coverage together with the size and separation of pentacene islands. The results are in good agreement with AFM investigation that encourages the use of this type of investigation in in-situ experiments.

(Received September 16 2008)

(Revised November 20 2008)

(Accepted January 20 2009)

(Online publication March 27 2009)


  • – Theories of X-ray diffraction and scattering;
  • – X-ray reflectometry (surfaces, interfaces, films);
  • 61.43.Hv – Fractals; macroscopic aggregates (including diffusion-limited aggregates);
  • – Polymers, organics