Epitaxy of an Organic Semiconductor Templated by Molecular Monolayer Crystals

Abstract

Molecular template growth is an efficient approach to enhance the crystallinity of organic semiconductor materials deposited by physical vapor deposition methods. Lattice matching, large grain size, and large monolayer coverage are critical figures of merits to evaluate effective templates. Here, solution-processed molecular monolayer crystals (MMCs) with 100% monolayer coverage and large single-crystalline domain size present the optimum form of molecular templates, which are successfully utilized for the growth of organic semiconductor thin films. Commensurate epitaxy growth over a large area was observed, and the reason for widely observed lamella structures in thin films was disclosed. In addition, the MMCs are proven effective in templating the growth of various high-performance organic semiconductor materials into orientated thin films. The MMC template provides an efficient approach to enhance the crystallinity and regulate the molecular orientation of organic semiconductor thin films.