Organic molecular beam deposition: Growth studies beyond the first monolayer

We review recent work on organic molecular beam deposition (OMBD) with emphasis on growth studies beyond the first monolayer, i.e. the evolution of the film structure and morphology. First, we briefly discuss general issues related to growth physics, including epitaxial relations, surface and interface energies, growth modes, correlation functions, dynamic scaling, and growth exponents. We also point out the general features that distinguish organic systems from inorganic systems, such as the different interaction potentials and the internal degrees of freedom of organic molecules. Then we discuss selected case studies, organised according to the role of the substrate (insulators, metals, semiconductors), covering examples from various organic semiconductors, namely perylene-derivatives (in particular diindeno-perylene (DIP) and 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA)), phthalocyanines, and oligoacenes (anthracene, tetracene, pentacene). Finally, we briefly discuss organics-based heterostructures and indicate some open problems and future directions.