Organic thin film transistor (OTFT) is expected as a switching device for flexible displays because organic semiconductor thin films can be fabricated by solution process at highest process temperatures lower than 150 °C, which allows us to use flexible and inexpensive plastic substrates. In this chapter, in the light of requirements for practical thin film transistor materials, how the requirements can be satisfied with a new type of organic semiconductor, i.e., liquid crystalline organic semiconductors, is described. At the same time, the state of the art of OTFT materials is described with a representative liquid crystalline organic semiconductor of 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene, Ph-BTBT-10 exhibiting highly ordered smectic liquid crystalline phase.

Chapter Contents:

• 17.1 Introduction
• 17.2 Liquid crystalline organic semiconductors
• 17.3 Reliable fabrication process using liquid crystallinity
• 17.4 Enhanced thermal durability with highly ordered liquid crystal phase
• 17.5 High TFT performance of polycrystalline TFTs fabricated with liquid crystalline Ph-BTBT derivative
• 17.6 Conclusion
• References

Inspec keywords: liquid films; semiconductor thin films; organic field effect transistors; thin film transistors; organic semiconductors; smectic liquid crystals; crystallisation; liquid crystals

Other keywords: flexible plastic substrates; OTFT materials; liquid crystalline organic semiconductor; smectic liquid crystalline phase; organic thin film transistor; 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene; temperature 150.0 degC

Subjects: Other field effect devices