Measuring Molecular Structure at the Active Interface in Functioning Organic Field Effect Transistors via Vibrational Sum Frequency Generation

Technical: This project uses interface-selective vibrational sum frequency generation spectroscopy, a nonlinear optics technique, to study molecular vibrations and their orientations at the active interface in organic field-effect transistors. The object of the project is to characterize the interface prior to and during device operation to gain insight into the relationships between interfacial molecular structure and function. It aims to advance the level of understanding not only in the fields of materials science and engineering where the devices are developed and tested, but also at the level of molecular design and synthesis by prescribing the features that need to be built into next generation molecules for efficient materials performance. The in-situ nature of experiments performed during organic field-effect transistor activation will provide a new perspective on the materials response from inside the functioning device, with the potential to describe not only what changes, but also what the timescales of change are and how these properties relate back to the macroscopic electrical response.

Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance. The interdisciplinary nature of this project creates a training environment for undergraduate and graduate students, who are skilled in not only materials processing, but also electrical and spectroscopic techniques. The PI and his research team are actively involved in outreach activities. The PI, for example, is an active presenter on concepts of climate change for the FIRST LEGO League. These outreach activities not only seek to instill excitement about science in general, but to also make connections between the materials properties observed by the participants and the real-world technologies they are familiar with, such as plastic containers and cell phones.