Semiconducting properties of p- and n-type organic nanofiber/poly(methyl methacrylate) composite films for film rectifier

• The p-type FET of P3HT nanofiber/PMMA composite film was measured.
• The n-type FET of PTCDI-C13 nanofiber/PMMA composite film was measured.
• The pn junction of these composite films showed the rectifying effect.
• The rectifying effect showed a diode region with the ideal factor of 2.30.

We investigated the field-effect mobility of regioregular poly(3-hexylthiophene) (P3HT) and N,N′-ditridecyl-3,4,9,10-perylenetetracarboxyl diimide (PTCDI-C13) nanofibers composited in poly(methyl methacrylate) (PMMA) with varying P3HT/PMMA or PTCDI-C13/PMMA ratio, solvent species, and doping concentration by fabricating the field effect transistor (FET) of these composite films. Both composite films functioned as a p- or n-type semiconducting layer of FET, and the apparent field-effect mobility gradually increased with increasing P3HT or PTCDI-C13 ratio, and was estimated to be about 4.7 × 10−3 cm2 V−1 s−1 (P3HT nanofiber/PMMA composite, P3HT weight ratio = 10%) and 2.0 × 10−5 cm2 V−1 s−1 (PTCDI-C13 nanofiber/PMMA composite, PTCDI-C13 weight ratio = 20%). In addition, a pn junction between P3HT nanofiber/PMMA and PTCDI-C13 nanofiber/PMMA composite films was fabricated to examine the rectifying effect. The rectifying effect was obtained and an appropriate diode region was observed in the forward current with the ideal factor n of 2.30. The rectifying effect can be derived by a simple fabrication method, i.e., simply pasting n- and p-type flexible films together, which gives us a novel methodology for fabricating flexible semiconducting devices.

I–V characteristics p-n junction organic diode.Figure optionsDownload as PowerPoint slide