Experimental and modeling study of low-voltage field-effect transistors fabricated with molecularly aligned copolymer floating films

In order to reduce the cost of next generation flexible and printed electronic devices, and enhance their performance, it is expected that they can be produced using simple solution processable techniques. In this paper, we have successfully demonstrated the application of a simple method to obtain molecularly aligned floating films of an organic semiconducting polymer, diketopyrrolopyrrole-naphthalene (PDPP-TNT), on top ofwater.Themacromolecular alignment in thesefilms deposited over glass susbstrates was confirmed by atomic forcemicroscopy, polarized opticalmicroscopy and polarizedUV–vis absorbance spectroscopy. Whenthe PDPP-TNTfloating filmswere deposited as the active layer in organicfield-effect transistors (OFETs), the devices exhibitedmobility values as high as 1.3 cm2V−1 s−1 at low operating voltages (6V). Furthermore, we have also performed a theoreticalmodeling study usingAim-Spice Level 15model to extract theOFETparameters.By varying the tuning parameters, themodeling data fits well with the experimental data ofPDPP-TNTOFETs