Balance of Horizontal and Vertical Charge Transport in Organic Field-Effect Transistors

Beyond the usual, lateral layouts for organic field-effect transistors (OFETs), vertical designs allow for high current densities and fast switching, but charge transport in such a configuration is not well understood. This study integrates experiments on light-emitting transistors with drift-diffusion simulations to investigate the formation of the conduction channel in a vertical OFET. The authors present a model for the lateral extent of the channel, and its scaling behavior. The results will allow us to find better routes to optimize such vertical OFETs, and the methodology extends to other vertical devices as well.