Ordered organic-organic multilayer growth

Crystalline order and orientation influence both the electronic and optical properties of thin organic crystalline films. Here, we demonstrate the quasiepitaxially ordered growth via organic vapor phase deposition of two organic materials, 1,4,5,8-naphthalene-tetracarboxylic-dianhydride and dibenzotetrathiafulvalene-tetracyanoquinodimethane on single-crystal substrates. To understand the quasiepitaxial orientations between the organic-inorganic and organic-organic lattices we compare geometrical lattice registry to full-structure van der Waals potential calculations, and find that only the complete description of the atomistic potential correctly matches experimentally observed orientations. We also demonstrate single-crystalline film growth of alternating multiple quasiepitaxial layers of these two organic semiconductors, and discuss this phenomenon in the context of incommensurate quasiepitaxy and surface energy matching, which is distinct from the lattice-matching criterion for inorganic heteroepitaxy.