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CAER Seminars

Metrology to enable the commercialization of organic electronics for an emerging flexible hybrid electronics industry

David Gundlach, Thin Film Electronics Project in the Nanoelectronics Group at NIST

April 2, 2015 at 4:30pm
SAB Conference Center
UK Center for Applied Energy Research


The combination of conventional high performance semiconductor integrated circuits (ICs) with robust, inexpensive, flexible substrates, displays, sensor arrays, and sparsely distributed lower performance conditioning circuits, switches, and memory provides pathways for unconventional electronic applications and new high dollar value manufacturing markets. This unorthodox approach of integrating disparate electronic materials and components on mechanically flexible substrates is commonly referred to as Flexible Hybrid Electronics (FHE). In contrast to strictly scaled silicon IC approaches, the performance of FHE systems is most appropriately defined by the specialized functionality achieved. Organic electronic devices and materials are among the most promising approaches for providing the tailored functionality needed to realize diverse FHE applications because of their compatibility with flexible substrates and unique electronic and optical properties. However, growing a robust and commercially attractive organic electronics sector necessitates accurate measurement methods, models, and data to facilitate the rational design of new materials and enable efficient manufacturing processes, circuit design, and the creation new device and system architectures.

In this presentation I will discuss our recent advances in impedance spectroscopy and transient perturbation measurements and models that complement conventional DC current-voltage measurements, and provide a more nuanced approach to understanding the effect of trapped and mobile charge density on device operation for organic photovoltaics. These contact based measurements are used to provide a framework to validate purely optical measurements that probe bulk properties and are better suited for manufacturing environments. Our combined approach gives greater insights to limitations in device performance due to the device design rather than a materials intrinsic properties. Impedance spectroscopy measurements are then used to disentangle contact effects from channel properties for organic thin film transistors to show the general utility of this approach to probe fundamental processes and accurately quantify critical electronic properties for benchmarking material performance and as input data to physics based models for device optimization and circuit design.