Field effect transistors with organic semiconductor layers assembled from aqueous colloidal nanocomposites.
We demonstrate field effect transistors based on organic semiconductor molecules dispersed in a self-organized polystyrene (PS) latex bead matrix. An aqueous colloidal composite made of PS and tetrahexylsexithiophene (H4T6) is deposited with a micropipet into the channel of a bottom-contact field effect transistor. The beads self-organize into a network whose characteristic distances are governed by their packing. The semiconductor molecules crystallize in the interstitial voids, leading to the growth of large interconnected domains. Depending on the bead size and the ratio between H4T6 and PS, the fraction of the different phases in the polymorph can be controlled. In the transistors where the H4T6 metastable "red phase" is the largest, the device response and the charge mobility are comparable to those of sexithienyl thin films grown by high-vacuum sublimation.
Dionigi
Chiara
C
Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, Via P. Gobetti 101, I-40129 Bologna, Italy. c.dionigi@bo.ismn.cnr.it
Stoliar
Pablo
P
Porzio
William
W
Destri
Silvia
S
Cavallini
Massimiliano
M
Bilotti
Ivano
I
Brillante
Aldo
A
Biscarini
Fabio
F