Elucidating Structure-Property Relationships for Charge Carrier Mobility and Mobility Relaxation in Organic Semiconductor Blends using Kinetic Monte Carlo Simulations Informed by TEM Tomography

A detailed understanding of how materials structure on the nano- to meso-scale affects long-range charge transport behavior is needed to refine design rules for organic electronic devices. While this problem is acutely relevant in donor-acceptor blends for photovoltaic applications where the bulk heterojunction morphology is well-known to play a critical role in device performance, charge transport through crystalline-amorphous microstructures and in semiconductor-insulator blends for flexible transistors share similar physical characteristics. In this presentation, we will introduce a unique approach to developing structure-property relationships for charge transport in these systems using kinetic Monte Carlo simulations with material morphologies derived from spectroscopic transmission electron microscope tomography. We will then quantify how morphological features such as the domain size, domain shape, tortuosity, and structural hierarchy are expected to impact detailed charge transport characteristics such as the carrier density, temperature, and electric field dependence of the mobility and the mobility relaxation dynamics.