Programmable Heterostructure Organic Light-Emitting Diodes

• Main Author: 陳介偉
• Other Authors: 吳忠幟
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/44659112348965889088

碩士 === 國立臺灣大學 === 光電工程學研究所 === 89 === Organic light-emitting diodes (OLEDs) based on small molecular organic materials have been extensively studied because of their various merits suitable for flat panel display applications. In this thesis, we investigate the properties of a new silylated conjugated compound, Bis-4,4’-[(diphenylmethylsilyl)vinyl]biphenyl (DPSVB), and its use in heterostructure OLEDs. We find that DPSVB functions as a hole-blocking layer in the tri-layer device, α-NPD/DPSVB/Alq3, resulting into an efficient blue-emitting OLED. Furthermore, we disclose a new type of electrically programmable, i.e. reconfigurable, organic light-emitting devices (OLEDs) incorporating a thin hole-blocking layer, DPSVB, as the sacrificial fusing layer. In such devices, the hole-blocking layer has lower glass transition temperature than neighboring layers. By raising the internal temperature of the device above the transition temperature of the hole-blocking layer with a large enough current, inter-diffusion between organic layers could occur through such layer. As a consequence, neighboring layers are fused and a new path for carrier transport is formed, bypassing the hole-blocking property and altering the device characteristics. A device that emits blue light as fabricated but can be transformed into a green-emitting one is demonstrated. Such type of devices may be used for color pixels in OLED displays, user-programmable OLED applications, and non-volatile memory devices.