电致发光加速层二氧化硅的电子高场迁移率  

HIGH FIELD ELECTRON TRANSPORT OF AMORPHOUS SiO 2 AS ACCELERATING LAYER IN THE LAYERED OPTIMIZATION TFEL

作　　者：娄志东[1,2,3] 徐征[1,2,3] 徐春祥[1,2,3] 于磊[1,2,3] 滕枫[1,2,3] 徐叙[1,2,3] 

机构地区：[1]天津理工学院材料物理研究所 [2]北方交通大学物理系 [3]中国科学院长春物理研究所激发态物理开放研究实验室

出　　处：《物理学报》1998年第1期139-145,共7页Acta Physica Sinica

基　　金：国家自然科学基金;天津市21世纪青年基金

摘　　要：根据非晶态半导体的能带理论，讨论了分层优化薄膜电致发光方案中非晶二氧化硅加速层中的电子在高电场中的输运行为．研究结果表明：在高电场下，由于电场的存在降低了陷阱之间的平均势垒高度．在费密能级附近处的杂质及缺陷定域态和导带尾定域态中，电子的输运主要表现为电场增强的热辅助式跳跃传导；而在导带扩展态中，电子的输运仍像晶态半导体那样表现为共有化运动．此外，以实验数据为基础，计算出了非晶二氧化硅中电子的迁移率、最小金属电导率、导带迁移率边界状态密度及费密能级处的状态密度．Abstract Amorphous SiO 2 is used as the accelerating layer in the layered optimization thin film electroluminescent devices. In this paper we discuss the effects of high electric fields on the transport of electrons in amorphous SiO 2. The energy differences between two localized states in the vicinity of the Fermi level or in the tail of the conduction band are lowered due to high electric fields. Therefore, electron transport in these localized states is in the form of thermally assisted hopping conduction strengthened by electric fields. Based on the experimental data we calculate the average mobility value of electrons in the conduction band, the minimum metal conductivity and the densities of states near the Fermi level and the mobility edge.

关 键 词：电子输运 二氧化硅 电致发光 加速层 高电场 

分 类 号：TN383.101[电子电信—物理电子学] O471.5[理学—半导体物理]