By Janice K. Mahon, Min-Hao Michael Lu, Universal Display Corp., Ewing, New Jersey
VTE has been the leading technology for OLED production, but OVPD, IJP and LITI have the potential to drive display performance and manufacturing efficiencies in future device generations. For OLED technology to advance in FPD applications, its production technology must continue to achieve device performance advances and manufacturing cost reductions.
An OLED typically consists of a stack of organic layers sandwiched between two conductive films deposited onto a substrate. Within the organic stack, the emitting layer (EML) is critical. This layer determines the color of the light emitted, typically red, green and blue (RGB) for full-color displays; this layer also plays a major role in device efficiency. In 1997, researchers at Princeton University and the University of Southern California discovered that by adding phosphorescent dopants to the EML, the resulting phosphorescent OLEDs (PHOLEDs) could be up to four times more power-efficient than conventional, fluorescent OLEDs.
Universal Display Corp. then developed a class of new materials and device technology to enable the commercialization of this approach. Based on the demonstrated performance from phosphorescence, Pioneer introduced the first product containing PHOLED technology in a commercial product late in 2003. Since then, OLED manufacturing capacity has been quickly increasing (see “OLED opportunity”).
Julie MacShane, Managing Editor, SST at email: [email protected]