Self-standing chitosan films as dielectrics in organic thin-film transistors

Organic thin film transistors, using self-standing 50 !m thick chitosan films as dielectric, are fabricated using sublimed pentacene or two conjugated polymers deposited by spin coating as semiconductors. Field-effect mobilities are found to be similar to values obtained with other dielectrics and, in the case of pentacene, a value (0.13 cm 2 /(V·s) compara- ble to high performing transistors was determined. In spite of the low On/Off ratios (a maximum value of 600 was obtained for the pentacene-based transistors), these are promising results for the area of sustainable organic electronics in general and for biocompatible electronics in particular.