论文部分内容阅读
通过分析聚合物电致发光器件中载流子注入、输运、激子的解离与复合过程 ,提出了激子解离与复合的理论模型 .基于电流连续性方程和Poisson方程 ,给出了激子复合密度、电流密度及复合效率表达式 研究两电极与有机层之间在Ohmic和Fowler Nordheim接触条件下载流子迁移率对器件中激子的复合密度及外加电压和注入势垒对器件电流和复合效率的影响 结果表明 :1)在一个较宽的注入势垒和迁移率范围内 ,复合密度不是由两个注入电极的相对注入比决定而是由有机层电子和空穴迁移率之比所支配 ;2 )固定阴极势垒 ,而阳极势垒由小变大时 ,器件电流由接触限制向空间电荷限制转变 ;3)复合效率随外电压升高先增加 ,当电压达一临界值时而陡降 ,存在一个最佳的注入势垒值 结果说明 :电极与有机层的能带匹配及有机层间的迁移率匹配对器件复合发光有着极其重要的影响。其计算值与所报道的理论结果相符
By analyzing the carrier injection, transport and exciton dissociation and recombination processes in polymer electroluminescent devices, a theoretical model of exciton dissociation and recombination is proposed. Based on the current continuity equation and the Poisson equation, Exciton recombination density, current density and compound efficiency expression of the two electrodes and the organic layer between Ohmic and Fowler Nordheim contact conditions in the carrier mobility of the device exciton recombination density and applied voltage and implanted barrier on the device current The results show that: 1) In a wide range of injection barrier and mobility, the recombination density is not determined by the relative injection ratio of two implanted electrodes but by the ratio of the electron-hole mobility of the organic layer (3) The recombination efficiency first increases with the rise of the external voltage, and when the voltage reaches a critical value, the device current changes from the contact limit to the space charge limit Steep drop, there is an optimal value of the injected barrier results show that: the electrode and the organic layer of the band matching and the mobility of organic layer matching is extremely important for the device composite luminescence influences. The calculated value is consistent with the reported theoretical result