We have investigated the dependence of hole mobility on thickness in free-standing films of bisphenol-A-polycarbonate (PC) doped with 30 wt% p-diethylaminobenzaldehyde diphenylhydrazone (DEH). Carrier generation in a time-of-flight (TOF) experiment was achieved through direct ionization of dopant molecules by electron impact using an electron gun supplying pulses of monoenergetic electrons in the range of 2 to 50 keV. The position of dopant ionization depends upon the electron energy and three TOF variants have been recently developed and used in this study. We have found that the hole mobility generally decreased with increasing film thickness with concomitant acceleration of the post-flight current decay indicating that the transport process approaches the steady-state regime, this process happening slightly faster than our model predicts. Numerical calculations have been compared with experimental data. The results are discussed in detail. The way to reconcile ostensibly contradictory interpretations of our results and those commonly reported in literature relying on photo injection technique has been proposed.

我们研究了掺杂有30 wt％p的双酚A-聚碳酸酯（PC）的自立膜中空穴迁移率对厚度的依赖性。-二乙氨基苯甲醛二苯hydr（DEH）。飞行时间（TOF）实验中的载流子生成是通过使用提供2至50 keV范围内的单能电子脉冲的电子枪通过电子撞击使掺杂剂分子直接电离来实现的。掺杂剂电离的位置取决于电子能量，最近已开发出三种TOF变体并用于本研究中。我们发现，空穴迁移率通常随膜厚的增加而降低，同时伴随着飞行后电流衰减的加速，这表明传输过程接近稳态状态，该过程发生的速度比我们的模型预测的要快。数值计算已与实验数据进行了比较。结果进行了详细讨论。