Chapter 4 - Organic Field-Effect Transistors for Large-Area Electronics

Abstract

This chapter focuses on the field of organic thin-film field-effect transistors (OTFTs). As in traditional inorganic semiconductors, organic semiconductors function either as p-type, in which the majority charge carriers are holes, or n-type, in which the majority charge carriers are electrons. OTFTs based on conjugated polymers, oligomers, or fused aromatics are envisioned as a viable alternative to more traditional, mainstream thin-film transistors (TFTs) based on inorganic materials. Because of the relatively low mobility of organic semiconductors, OTFTs cannot rival the performance of field-effect transistors based on single-crystalline inorganic semiconductors, such as Si, Ge, and GaAs, which have charge carrier mobilities of three or more orders of magnitude higher Consequently, OTFTs are not suitable for use in applications requiring very high switching speeds. However, the unique processing characteristics and already demonstrated performance of OTFTs suggest that they can be competitive candidates for existing or novel TFT applications requiring large area coverage, low-temperature processing, structural flexibility, and especially low cost.