The objective of this research is to study effects, mechanisms, and limits of charge implantation into gate dielectrics of organic/plastic field-effect transistors and to develop processes for charge implantation that are fully integrated with roll-to-roll printing. Charged dielectrics in transistors offer the opportunity to preset the conductance of OFETs without addressing gate electrodes during operation, to impart a nonvolatile threshold voltage offset to transistors, to reverse the majority carrier in a single organic semiconductor, and most importantly, to fabricate transistors with different characteristics out of the same materials and with the same architectures, greatly diminishing the need to print multiple semiconductors when fabricating complex printed/plastic circuits. The approach is to synthesize new semiconductors with functional groups and energy levels optimized for charging stability and maximum charge-induced modulation, utilization of dielectrics with improved film-forming capabilities via printing processes and the most hydrophobic possible surface functionalities, optimizing charging dynamics, and process transfer to rapid roll-mounted charging apparatus located in Germany.
The intellectual merit will include a valuable new approach for printing circuits of commercial interest for wireless identification tags, for which there are no printable, practical, and stable alternatives, and which are increasingly in demand. Sensor arrays for homeland security and reconfigurable plastic circuits are other likely technological applications. New compounds, solids, and physical phenomena will be explored.
Broader impact includes undergraduate engineering laboratory enhancements, demonstrations for middle and high school outreach events, and modules suitable for high school electronics instruction. The international collaboration will be especially enlightening for graduate student trainees.
