ABSTRACT Interfacial Studies in Organic Field-Effect Transistors

Organic field-effect transistors (OFETs) are potential components for large-area electronics because of their attractive advantages: light weight, cost-effective and large-area process-ability, flexibility and resonable performance potential. However, the commercialization of OFETs faces several technical obstacles. Low mobility of organic semiconductors limits the current-carrying capacity; high operation voltage restricts their use in many applica-tions; easy degradation in air and instability under electrical stress usually make the lifetime too short to be useful; and contact resistance and contact matching also limit the charge injection to the semiconductor. Many of the above problems relate to interfaces in OFETs. There are two important interfaces in OFETs. The interface between organic semiconductor and the dielectric layer is of crucial importance since it is the location where charge transport in the channel occurs. The other important interface in OFETs is between the semiconductor and the contacts, where the charge injection and removal happen during device operation. Surface treatment of the contacts for bottom-contact devices is usually necessary to achieve both a good semiconductor microstructure and excellent contact performance