Molecular Technology for Organic Semiconductors Toward Printed and Flexible Electronics

Organic semiconductors are of scientific and technological interest due to their potential in printable and flexible electronic applications such as organic field-effect transistors ( OFET s), organic light-emitting diodes ( OLED s), and organic photovoltaic cells ( OPV s). The functions of organic semiconductors are generated by intermolecular charge transport between constituent neighboring π-conjugated molecules as well as the geometric and energetic features, which essentially determine device performance. Therefore, versatility in material design offers enormous potential to build molecules suitable for organic semiconductors, facilitating practical industrialization. This chapter focuses on the historical impact of small molecular-type semiconducting π-cores, such as acenes, heteroacenes, and other promising and high-impact organic semiconducting molecules of hole- (p-type) and electron- (n-type) transport characteristics based on “ molecular technology .” Furthermore, achievements in device performance of organic semiconductors in polycrystalline- and single-crystalline-based devices along with recent solution process techniques are described.