Katherine Aidala, Mount Holyoke College

Organic semiconductors offer the promise of solution processible, flexible electronics, but the charge transport in these disordered films is not fully understood.  Atomic Force Microscopy (AFM) brings a nanoscale tip close to or in contact with the surface of a sample and is best known for measuring the topography of the surface.  The AFM tip responds to any force, and a charged tip will respond to electric fields, allowing nanoscale mapping of electrical properties.  This talk will focus on a technique under development that enables us to learn about real time charge movement recorded in an organic field effect transistor.  By stepping the voltage on the gate, charges will be injected in or extracted from the organic thin film.  Kelvin Probe Force Microscopy (KPFM) allows us to measure the potential at the surface of the transistor, with a time resolution of around 3ms.  We are able to study the population and depopulation of charge carrier traps with this technique.