电流模式Poly-Si TFT AM-OLED像素单元的模拟设计  

Simulation on Current Programmed Poly-Si TFT AM-OLED Pixel

作　　者：郭斌[1] 吴春亚[1] 孟志国[1] 林立[1] 杨广华[1] 李娟[1] 周祯华[1] 熊绍珍[1] 

机构地区：[1]南开大学光电子所,天津300071

出　　处：《光电子．激光》2004年第2期142-146,共5页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金资助项目(60077011;69907002);国家863计划资助项目(2002AA303261);天津市自然科学基金资助项目(023602011)

摘　　要：模拟和分析了作为电流模式多晶硅薄膜晶体管(poly SiTFT)有源矩阵有机发光二极管(AM LOED)像素单元的poly SiTFT/OLED耦合对的J V特性和poly SiTFT电流镜的I V特性。使用Mathcad数学计算软件和AIM SPICE电路模拟工具,分别对OLED和TFT耦合对和TFT电流镜进行了模拟计算。理论上,采用电流模式的poly SiTFTAM OLED可以解决器件间的不一致性问题。无论迁移率的不一致还是阈值电压Vth的差异都可以被补偿,从而使灰度的一致性得以改善。因为采用了倒置的OLED结构,可以用N型poly SiTFT作为电流阱来驱动OLED,所以像素的性能进一步优化。结果表明,poly SiTFT/OLED耦合对的驱动电压低,在200A/m2下不超过8V;而TFT电流镜的跟随能力很好,在0.0～2.5μA时饱和电压只有1.5～2.5V。The J-V characteristics of the poly-Si TFT/OLED coupling pair and the I-V characteristics of poly-Si TFT current mirror were simulated and analyzed as a pixel unit of current programmed poly-Si TFT AM-OLED. The simulation and computation were completed by using Mathcad and AIM-SPICE. Theoretically, the poly-Si TFT AM-OLED with current programmed mode can resolve the device-to-device uniformity problem. Both the mobility non-uniformity and the Vth variation can be compensated, and the gray scale uniformity will thus be improved. Since an inverted structure of OLED is adopted, the N type poly-Si TFT can be used as current sink so that the performance of the pixel can be further improved. The results show that the poly-Si TFT/OLED pair has a low driving voltage, which is not larger than 8 V under 200 A/m2. The poly-Si TFT current mirror has a perfect following capacity and its saturation voltage is only 1.5-2.5 V under 0.0-2.5 μA.

关 键 词：有机发光二极管 多晶硅薄膜晶体管 有源矩阵 电流编程驱动 电流镜 AM-OLED 

分 类 号：TN383.1[电子电信—物理电子学]