Efficiency improvement of organic light-emitting diodes using 8-hydroxy-quinolinato lithium as an electron injection layer

• Published in: Thin solid films Vol. 478; no. 1-2; pp. 252 - 255
• Main Authors: Zheng, Xinyou, Wu, Youzhi, Sun, Runguang, Zhu, Wenqing, Jiang, Xueyin, Zhang, Zhilin, Xu, Shaohong
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.05.2005; Elsevier Science
• Subjects: 8-Hydroxy-quinolinato lithium; Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Efficiency; Electroluminescence; Electronics; Exact sciences and technology; Improvement; Light-emitting devices; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optoelectronic devices; Organic light-emitting diode; Other luminescence and radiative recombination; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; 8-Hydroxy-quinolinato lithium; Organic light-emitting diode; Improvement; Efficiency; Thickness; Voltage current curve; Dipole approximation; Electron injection; Quinoline; Aluminium compound; Electroluminescence; Experimental study; Current density; Organic compounds; Light emitting diode
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2004.08.020

Organic light-emitting diodes (OLEDs) using tris-(8-hydroxy-quinolinato) aluminum (Alq3) as an emitter, 8-hydroxy-quinolinato lithium (Liq) as an electron injection layer, were prepared. Experimental results show that the efficiency of device with Liq is three times higher than that without Liq. The device using Liq as an injection layer is less sensitive in efficiency to the Liq thickness than that using LiF. In addition to the Alq3 based devices, Liq is also very effective as an electron injection layer for 4,4′-bis(2,2-diphenylvinyl)-1,1′-biphenyl based blue OLED and poly (2-methoxy,5-(2′-ethyl-hexyloxy)-1,4-phenylenevinylene) based orange polymer OLED.