单层有机器件的电子传输特性的数值模拟  

Numerical simulation of electrical transport characteristics of single layer organic devices

作　　者：胡玥[1] 饶海波[1] 

机构地区：[1]电子科技大学光电信息学院,成都610054

出　　处：《物理学报》2009年第5期3474-3478,共5页Acta Physica Sinica

摘　　要：在漂移扩散模型的基础上建立了单层有机器件的模型,包括了电荷注入、传输、空间电荷效应和陷阱的影响.电荷注入考虑了热电子发射电流和隧道电流.模拟得到的结果和文献中报道的实验测试数据一致.模拟研究了各个因素对器件J-V曲线的影响,电流和器件长度成反比,电流随着空穴注入势垒的减小而增加.电子注入势垒从1.7eV减少到0.5eV时,电流随着电子注入势垒的减小而减小,这主要是因为有机材料中电子迁移率太小,电子注入电流的增加可以忽略,而电子注入势垒的减小使内建势增加,在同样的电压下,场强变小,空穴注入电流变小;当电子注入势垒继续减小到0.1eV时,电流增加.这是因为有机材料的电子迁移率低,注入的电子堆积在阴极附近,使阳极附近的电场增大,空穴电流变大.A numerical model of organic devices, which includes charge injection, transport, space charge effect and trap influence, was discussed in this paper. Both thermionic emission over the barrier and tunneling through the barrier are considered in charge injection into the bulk. The result is in good agreement with the experimental data. Several parameters have been simulated to study the change of J-V characteristics. The current decreases with the increases of the length of device. The current density becomes higher when the hole injecting barrier is smaller. However, when the electronic injecting barrier decreases from 1.7 eV to 0. 5 eV, the current density becomes smaller. This is because the electronic mobility is too small, and the electronic injecting current is negligible compared with the hole current. When the electronic injecting barrier is smaller, the built-in potential becomes bigger, under the same applied voltage, the field diminishes, and the hole current becomes smaller. When the barrier is reduced to 0.1 eV, the current density increases. This is because the electronic mobility is too small, and electrons accumulate near the cathode, the electric field around the anode increases and the current increases.

关 键 词：有机器件 传输特性 数值模拟 

分 类 号：O482.4[理学—固体物理]