12 - Epitaxy of Small Organic Molecules

Abstract

Crystal growth phenomena are critical in the creation of organic thin-film materials and devices. Insight into the fundamental epitaxial processes of interface formation, nucleation, and surface transport can be obtained from epitaxy on organic single-crystal surfaces. Applications demand the creation of organic-inorganic interfaces between organic crystalline thin films and inorganic metal or insulator substrates for which deposition yields thin films with structures ranging from amorphous layers to epitaxial crystals. Epitaxial methods include organic molecular beam deposition, vapor transport, and solution phase deposition. Each method provides unique kinetic processes and opportunities in interface formation, the design of thin-film crystals with favorable morphologies, and to yield particular crystalline polymorphs. Organic epitaxial structures can be characterized by a wide variety of structural and microscopic techniques, including X-ray diffraction and scattering, optical probes, scanning probe microscopy, and electron diffraction and microscopy. The scope of organic epitaxial techniques are expanding to include multicomponent organic compounds and large low-symmetry molecules relevant to biomaterials.