International Research Fellowship Program: Light-Emitting Organic Memory of (LE-OMEM) Based on Photochromic Hole Transport Materials in Organic Light-Emitting Diodes (OLEDs)

Shallcross Richard C, Arlington TX

Investigators

Abstract

0965245 Shallcross The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four-month research fellowship by Dr. R. Clayton Shallcross to work with Dr. Klaus Meerholz at the University of Cologne in Germany. The scientific objective of this twenty-four month research fellowship is to develop solution-processable non-volatile organic memory (OMEM), image processing and display devices that may be optically switched via photochromic dithyenylethene (DTE) compounds in the active layer. The project focuses on both light-emitting and non-emitting devices based on organic light-emitting diodes (OLEDs) and ?hole-only? devices, respectively. The overall goal of this research fellowship is to design solution-processable (i.e. crosslinkable) photochromic DTE-based molecules that are specifically sensitive to blue, green, red and IR radiation and incorporate them into working devices, which will ultimately lead to full color image processing and complementary display capabilities that exhibit high contrast between their ON and OFF states (i.e. high ON/OFF ratios), low power consumption, and high fatigue resistance (cyclability). The broader significance of this project lies in the ability to utilize basic solution processing methods (e.g. spin coating) to easily and inexpensively process thin film non-volatile memory devices. In contrast to conventional device processing conditions utilized for conventional inorganic semiconductors, low-temperature solution processing will be employed to afford high-quality large area multi-layered thin films composed of pure or doped organic semiconductors on a variety of both rigid and plastic substrates. Some of the existing non-volatile memory technologies based predominately on organic compounds in metal-insulator-metal (MIM) and thin film transistor (TFT) formats do show reasonable voltage-induced ON/OFF ratios for current, but are not simultaneously optimized with respect to fatigue resistance (cyclability), power consumption (operating voltage) and ease of processing. Furthermore, light-emitting organic memory (LE-OMEM) devices offer the possibility of not only current read out for conventional memory and image processing applications, but also optical readout due to OLED emission modulation, which may find additional applications in ?smart? display technologies. Rational design of OMEM devices, incorporating a diverse catalog of structurally unique photochromic compounds, offers the prospect of utilizing low-temperature, low-cost and facile solution processing methods for optimizing full color image processing and complementary display devices.