Programmable organic light-emitting devices

In this letter, we report a promising type of electrically programmable, i. e., reconfigurable, organic light-emitting devices (OLEDs) incorporating a thin carrier-blocking layer as the sacrificial fusing layer. In such device s, the carrier-blocking layer has a lower glass transition temperature than neighboring layers. By raising the internal temperature of the device abov e the transition temperature of the carrier-blocking layer with a large eno ugh current, interdiffusion between organic layers could occur through such a layer. As a consequence, neighboring layers are fused and a new path for carrier transport is formed, bypassing the carrier-blocking property and a ltering the device characteristics. A device that emits blue light as fabri cated but can be transformed into a green-emitting one is demonstrated. Suc h a type of device may be used for color pixels in OLED displays, user-prog rammable OLED applications, and nonvolatile memory devices.(C) 2001 America n Institute of Physics.