TIPS-pentacene crystalline thin film growth

The crystalline film growth of TIPS-pentacene thin films by confined solution deposition is investigated. The crystalline thin films grow dendritic in the initial stage and continue to grow to elongated plate-like crystals when the solution is deposited in a confined space in-plane. The majority of the thin film, containing smaller thin crystals, is formed within the first 10 s after depositing the solution and continues to grow in minutes to millimeter sized single crystals. By atomic force microscopy we show that impurities are expelled by the growing crystals and clusters accumulate at step edges on the surface of the larger crystals. The influence of crystal thickness and orientation on the electronic transport in field-effect transistors is studied, and shows an optimum performance for devices with thin elongated crystals that are aligned parallel to the electric field between the source–drain electrodes.

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► In situ observation of TIPS-pentacene during confined crystallization by cross polarized microscopy.
► Different growth mechanisms and grow speeds observed in a single crystalline film.
► Relationship between field-effect transistor performance and crystalline thin film morphology.
► Expelled impurity observation for large plate-like crystals at step edges.
► Crystal orientation dependence of the field-effect mobility.