Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Flexible and Printed Electronics

Summary

This project is focused on developing the measurement methods and polymer physics models needed to accelerate the innovation cycle for organic semiconductor-based devices, to enable bespoke, flexible, low cost electronics for the IoT, Industry 4.0, and healthcare. Specially, we are (1) developing and demonstrating measurement methods (soft and hard X-ray, IR, TEM, SANS, calorimetry, and swelling-based measurements), polymer physics models, and computational toolboxes (pyPRISM) focused on characterizing and predicting the local structure and orientation in organic semiconductor-based systems to link structure to device performance for device optimization and (2) developing in-situ and operando measurement methods to probe the kinetics and induced morphological changes during the doping process in organic electrochemical transistors (OECTs) to gain the understanding necessary to optimize the structure and performance of such devices.

Description

Approach

Developing commercial products based on organic electronics requires materials that deliver predictable and reproducible performance. One advantage of these materials is their compatibility with versatile solution processing methods. However, this advantage can lead to unpredictable performance and poor reproducibility because the critical microstructure of the material forms dynamically as the solution dries during manufacturing. Many process parameters influence the drying process and the microstructure formation is often hard to control.

We aim to develop and demonstrate multimodal analysis suites that combine information from the molecular level (IR-absorption, near edge X-ray absorption fine structure - NEXAFS) and crystalline structure (grazing-incidence wide-angle X-ray scattering - GIWAXS) with mesoscale (transmission electron microscopy - TEM, grazing-incidence small-angle X-ray scattering - GISAXS, vapor swelling, polarized soft X-ray scattering - pRSoXS) tools to “triangulate” on the film structure to correlate to device performance. These tools are deployed in both static (structure<->function) and in-situ (process<->structure) modalities. Through the combination of static and in-situ modalities we seek to elucidate the mechanisms underlying (meso)phase and structure development during processing and link key material properties to device performance.

Major Accomplishments

Recent Reviews

Organic Photovoltaics (OPV)

Schematic of an organic photovoltaic device, showing device components including the bulk heterojunction consisting of the electron donating and electron accepting organic semiconductors.
Typical structure of a bulk heterojunction based OPV device.

Organic Thin-Film Transistors (OTFT)

Schematic of an organic thin film transistor showing gate, dielectric, source, drain, and organic semiconductor.
Credit: Chad Snyder

Organic Electrochemical Transistors (OECT)

Animated gif showing swelling and color change (due to doping/de-doping) of an organic electrochemical transistor upon water and ion infiltration and exfiltration.
Swelling and color change (due to doping/de-doping) of an OECT upon water and ion infiltration and exfiltration.
Credit: Chad Snyder
Created November 4, 2008, Updated March 1, 2023