The functional properties and technological utility of polycrystalline materials are largely determined by the structure, geometry, and spatial distribution of their multitude of crystals. However, crystallization is seeded through stochastic and incoherent nucleation events, limiting the ability to control or pattern the microstructure, texture, and functional properties of polycrystalline materials. We present a universal approach that can program the microstructure of materials through the coherent seeding of otherwise stochastic homogeneous nucleation events. The method relies on creating topographic variations to seed nucleation and growth at designated locations while delaying nucleation elsewhere. Each seed can thus produce a coherent growth front of crystallization with a geometry designated by the shape and arrangement of seeds. Periodic and aperiodic crystalline arrays of functional materials, such as semiconductors, can thus be created on demand and with unprecedented sophistication and ease by patterning the location and shape of the seeds. This approach is used to demonstrate printed arrays of organic thin-film transistors with remarkable performance and reproducibility owing to their demonstrated spatial control over the microstructure of organic and inorganic polycrystalline semiconductors.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: Part of this work was performed at CHESS, which was supported by the NSF and the NIH/National Institutes of General Medical Science via NSF award DMR-1332208. The research reported here was supported by the King Abdullah University of Science and Technology. A.A. is grateful to Saudi Arabian Basic Industries Corporation (SABIC) for the Career Development SABIC Chair.