A simple strategy for controlling the nanomorphology of semiconducting polymers on surface-modified polymer dielectrics as well as a technique for fabricating flexible OFETs.
Flexible organic field-effect transistors (OFETs) based on solution-processed semiconducting polymers and polymer dielectrics is of particular interest for the most advanced plastic electronics. However, current OFETs have limitations preventing them from being as advantageous as they could be. For example, the material used for inducing chain alignment is extremely brittle making it challenging to develop high mobility flexible transistors. Furthermore, due to the difficulty of aligning semiconducting polymers on meta-stable polymer dielectrics charge carrier mobilities have remained below industrial requirements. Therefore, a strategy for achieving high polymer alignment and high mobilities using a nanogrooved polymer dielectric, that is chemically and mechanically stable, is needed for the development of high mobility flexible OFETs.
Researchers at the University of California, Santa Barbara have created a simple strategy for controlling the nanomorphology of semiconducting polymers on surface-modified polymer dielectrics as well as a technique for fabricating flexible OFETs. These devices are comprised of a flexible substrate and flexible dielectric layers with semiconducting polymers that remain aligned. The one or more dielectric layers can increase mobility of the semiconducting polymers and/or alignment of the semiconducting polymers with one or more of the nanogrooves in the dielectric layers. Moreover, the flexible plastic FETs demonstrated excellent mechanical stability even under severe bending conditions. These results indicate significant achievements for solution-processed flexible OFETs, and demonstrate that high-mobility semiconducting polymers can be aligned by chemically stable soft nanostructures through directed self-assembly.
|United States Of America||Issued Patent||10,008,683||06/26/2018||2015-977|