The market for organic electronic devices is growing rapidly. Global sales of organic LED display technology for example are projected to increase from over $1 billion in 2010 to more than $6 billion by 2016. Improving the efficiency of organic CMOS circuits will be critical to the continued success of this industry. Like silicon (i.e. non-organic) CMOS circuits organic CMOS circuits are based on complementary logic thus they use both p-type and n-type field-effect transistors. Up until now p-channel organic semiconductors have been widely studied and have achieved excellent device performance and air stability but the development of n-channel organic semiconductors has significantly lagged behind. For the successful application of organic semiconductors in organic CMOS circuits it is essential to obtain both p-channel and n-channel semiconductors with high performance and air stability. Researchers in Prof. Zhenan Bao’s lab at Stanford University have developed several n-type dopants that have been found to work effectively on a variety of n-channel organic semiconductors. Both vacuum deposition and solution process were used in the course of the research. Their tests show that n-type doping definitely improves the air stability of n-channel organic thin-film transistors (OTFTs). This technology describes preparation of n-channel OTFTs with several n-type dopants. The invention opens up new opportunities for the use of air-sensitive n-channel organic semiconductors in many practical applications. A closely-related technology is Stanford Docket No. S10-055 “n-Type Dopants for Organic Electronics” invented by Zhenan Bao and Peng Wei.
Much higher air stability in ambient conditions due to the increase of electron charge carriers from strong n-type dopants.