Fabrication Of White Organic Light-emitting Diode With Blend Single-layer Structure And Study About Improving Its Properties

Recently the organic light-emitting diodes (OLED) has become a predominant contestant in most flat display technology because of its many advantages, such as full solid display; low driven voltage; flexible displays and so on. Now the scientists are making great efforts to realize the full color display. The white OLED devices can easily realize full color display with the sieve implement and be used to LCD's lamp-house. So the white OLED acts as more and more important roles in the area of OLED. We adopt the method of polymer mixed to fabricate two kinds of white organic light-emitting diode with blend single-layer Structure. All factors which affect the luminescent performance of OLED were analyzed in this paper. We considered that the characteristics of the interface between the organic layer and the cathode and the device structure are the crucial factors. In the light of the above analysis, the luminescent performance of white OLED devices were promoted by adopting heat treatment. In the end of this paper, we reported a new type of white OLED device which was fabricated by using polymer doped with organic small molecular material.1. PVK as host was doped with MEH-PPV, OXD-7 and PMMA. Using it we fabricated whiteorganic light-emitting diode with blend single-layer Structure. Then we particularly record the preparation process of the devices and accurately measured photoelectric characteristics of the devices. Heat treatment at low vacuum on this kind of devices at different temperature and time conditions was performed. After heat treatment, the luminescence performance of the above devices was improved obviously. Our experiments indicated that the optimum heat treatment condition for the MEH-PPV devices is 180℃,1 hour. We analyzed the reason of this phenomenon.2. LPPP as host is doped with MEH-PPV, OXD-7 and PMMA. Using it we fabricated whiteorganic light-emitting diode with blend single-layer Structure. Heat treatment at low vacuum on this kind of devices at the optimum condition (180℃,1 hour) was performed. After heat treatment, the luminescence performance of the devices was improved obviously. After analyzing, we think the reason of the enhancement of LPPP devices by adopting heat treatment may be similar with that of PVK devices. And we compared the difference of luminescent performance of these two kinds of devices.3. Polymer MEH-PPV PVK was doped with organic small molecular material Balq. We use itto fabricate a new kind of white organic light-emitting diode with blend single-layer Structure. And we simply analysised the doped mechanism of doped with organic small molecular material, accurately measured photoelectric characteristics of this sort of devices, validated the feasibility of using blend measurement to fabricate white organic light-emitting diode with blend single-layer structure.