A KAIST research study group led by Professor Steve Park from the Department of Materials Science and Engineering
Recently, solution-processable organic semiconductors are being highlighted for their prospective application in printed electronic devices, ending up being a practical strategy to make large-area versatile thin movie at a low expense. The field-effect movement of small-molecule organic semiconductors depends on the crystallinity, crystal orientation, and crystal size. A range of solution-based finishing methods, such as ink-jet printing, dip-coating, and solution shearing have actually been established to manage the crystallinity and crystal orientation, however an approach for establishing methods to increase the crystal size of organic semiconductors is still required.
To conquer this concern, the research study group established an inorganic polymer micropillar-based solution shearing system to increase the crystal size of an organic semiconductor with pillar size. Using this strategy, the formation procedure of organic semiconductors can be controlled specifically, and for that reason large-area organic semiconductor thin movie with controlled crystallinity can be made.
A range of solution-based finishing methods can not manage the fluid-flow of options properly, so the solvent vaporizes arbitrarily onto the substrate, which has trouble in the fabrication of organic semiconductor thin movie with a big crystal size.
The research study group incorporated inorganic polymer microstructures into the solution shearing blade to resolve this concern. The inorganic polymer can quickly be microstructured by means of standard molding methods, has high mechanical sturdiness, and organic solvent resistance. Using the inorganic polymer-based microstructure blade, the research study group controlled the size of little particle organic semiconductors by tuning the shape and measurements of the microstructure. The microstructures in the blade cause the sharp curvature areas in the meniscus line that formed in between the shearing blade and the substrate, and for that reason nucleation and crystal development can be controlled. Hence, the research study group made organic semiconductor thin-film with big crystals, which increases the field-effect movement.
The research study group likewise showed a solution shearing procedure on a curved surface area by utilizing a versatile inorganic polymer-based shearing blade, which broadens the applicability of solution shearing.
ProfessorPark stated, “Our new solution shearing system can control the crystallization process precisely during solvent evaporation.” He included, “This strategy includes another crucial criterion that can be used to tune the residential or commercial property of thin movies and opens a wide range of brand-new applications.
The outcomes of this work entitled “Inorganic Polymer Micropillar-Based Solution Shearing of Large-Area Organic Semiconductor Thin Films with Pillar-Size-Dependent Crystal Size” was released in the July 2018 concern of Advanced Materials as a cover post.