Organic CMOS technology by dielectric interface engineering

This work investigates the importance of electronic states at the dielectric / semiconductor interface for organic field effect transistor (OFET) charge carrier transport. It was determined, that balanced p- and n-type charge carrier transport in pentacene is possible, if an adequate gate dielectric is selected. It was further demonstrated, that the OFET charge carrier transport can be selectively influenced by either the introduction of charge carrier traps to the dielectric interface or the removal of such traps. By covering an electron trap afflicted silicon dioxide dielectric with a thin layer of oxidized Ca, which passivates and isolates available electron traps from the transistor channel, n-type transport in pentacene OFETs is achieved. In addition, it was demonstrated, that the introduction of electron traps into a Polymethylmethacrylat dielectric, using ultra violet radiation in ambient atmosphere, allows for the inversion of an otherwise unipolar n-type OFET to unipolar p-type. The possibility to realize OFETs of complementary polarity with an identical device cross section has allowed for the realization of an organic complementary metal oxide semiconductor inverter.