Numerical model of tandem organic light-emitting diodes based on a transition metal oxide interconnector layer

• Published in: Journal of semiconductors Vol. 35; no. 4; pp. 68 - 76
• Main Author: 路飞平 彭应全 邢永忠
• Format: Journal Article
• Language: English
• Published: 01.04.2014
• Subjects: Barriers; Carrier injection; Charge; Devices; Electric fields; Electrodes; Mathematical models; Semiconductors; TMOS; 串联式; 互连; 数值模型; 有机发光二极管; 注入势垒; 载流子注入; 过渡金属氧化物
• ISSN: 1674-4926
• DOI: 10.1088/1674-4926/35/4/044005

By utilizing a two-step process to express the charge generation and separation mechanism of the transition metal oxides （TMOs） interconnector layer, a numerical model was proposed for tandem organic light emitting diodes （OLEDs） with a TMOs thin film as the interconnector layer. This model is valid not only for an n-type TMOs interconnector layer, but also for a p-type TMOs interconnector layer. Based on this model, the influences of different carrier injection barriers at the interface of the electrode/organic layer on the charge generation ability of interconnector layers were studied. In addition, the distribution characteristics of carrier concentration, electric field intensity and potential in the device under different carrier injection barriers were studied. The results show that when keeping one carrier injection barrier as a constant while increasing another carrier injection barrier, carri- ers injected into the device were gradually decreased, the carrier generation ability of the interconnector layer was gradually reduced, the electric field intensity at the interface of the organic/electrode was gradually enhanced, and the electric field distribution became nearly linear： the voltage drops in two light units gradually became the same. Meanwhile, the carrier injection ability decreased as another carrier injection barrier increased. The simulation re- sults agree with the experimental data. The obtained results can provide us with a deep understanding of the work mechanism of TMOs-based tandem OLEDs.