Study On Blue And White Organic Light-Emitting Devices

Since C.W. Tang has reported high brightness organic light-emitting devices (OLEDs) with low operating voltage for the first time in 1987, OLEDs have received more and more attentions. As a new flat panel display technology, OLEDs have many merits such as: light weight, thin thickness, low cost, broad visual angle, fast response speed, active emitting, low energy consume, high brightness and efficiency, broad operating temperature, more choice of materials, availability for full color display and flexible display, etc. Owing to the research on new materials, optimization of device structure and improvement of fabrication processes, OLEDs have developed rapidly. So far, red and green monochromatic devices have been commercially available, but the efficiency and lifetime of blue OLEDs are relatively low comparing with red and green ones and limit the development of white OLEDs (WOLEDs) at some degree. In this dissertation, we have fabricated various blue and white OLEDs with different materials and device structures. We study on the relationship between the selection of materials and design of device structure to the efficiency and color saturation of OLEDs. We discuss the reason why the external quantum...