聚N-乙烯基咔唑-2,4,7,三硝基-9-芴酮电荷转移复合物薄膜的载流子迁移率

采用渡越时间法测量了PVC_z-TNF电荷转移复合物薄膜载流子的迁移率。观察到电子和空穴在输运过程中的差异:电子的渡越时间是大致均一的。空穴的渡越时间有一个分布,在电场作用下迁移可用Scher-Montroll的理论处理;并观察到在低电场下(E<1.8×10⁵V/cm)迁移率为一恒定值。结合暗电导率的测量对该材料的非欧姆性电导的本质进行了讨论,认为在强电场下载流子迁移率和浓度都随电场增加而增大。关键词：

DRIFT MOBILITIES OF CARRIERS IN AMORPHOUS FILMS OF PVCz-TNF CHARGE-TRANSFER COMPLEXES

The drift mobilities of carriers in amorphous charge-transfer complexes of PVCz-TNF were obtained by Time-of-Flight. Differences in the transport characteristics between electrons and holes were observed. The transient current trace of electrons has a knee by which the transit time can be determined, but. the current trace of holes is featureless indicating that t_T is dispersive. The transient current of holes can be analysed by Scher-Montroll theory. At low electrical field μ_h is independent of the field. Combining the results of dark conductivity measurements, we conclude that the non-ohmic conductivity at high field is contributed by the field-dependent mobilities and carrier concentrations that are both increasing with the field strength.