Investigation of Long-Term OLED Device Stability via Transmission Electron Microscopy Imaging of Cross-Sectioned OLED Devices

Investigating Organization
Lawrence Berkeley National Laboratory

Principal Investigator(s)
Gao Liu

Subcontractor
None

Funding Source
Building Technologies Program/NETL

Award
DOE Share: $849,750

Contract Period
9/1/07 - 8/31/10

The Lawrence Berkeley National Laboratory is proposing a three-year program to improve OLED lifetime and functionality by combining novel fabrication and state-of-the-art characterization techniques to understand the origins of device degradation in white light OLEDs.  The research will focus on the interfacial evolution at different stages of device lifetime to provide a comprehensive understanding of the interface degradation and resulting device characteristics to design more stable interfaces by controlling the light emitting polymer film morphology for improved lifetime.  This approach addresses the needs identified in the DOE sponsored Solid-State Lighting Workshop for approaches to OLED structures between he electrodes for improved performance low cost white light devices.

The proposed work would combine the advanced transmission electron microscopy imaging techniques with polymer morphology control to correlate the structure and interface changes to the device degradation process.  Techniques that better control the morphology of the light-emitting layer will be developed.  The ability to control the morphology of this layer will allow for optimization of the device for the desired performance attributes of improved efficiency and brightness.  Upon analysis, the morphologies that give the best long-term performance will be identified, along with the processes leading to these morphologies.  The approaches to stabilize the morphology and interface will also be studied in this work.

Content dated 2/08