کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1665665 | 1518050 | 2014 | 5 صفحه PDF | دانلود رایگان |
• Electron and hole mobilities in Alq3 were determined using impedance spectroscopy.
• The measured mobilities are consistent with those by a time-of-flight technique.
• Mobilities of thin semiconducting layer (~ 100 nm) can be measured.
The electron and hole drift-mobilities of tris(8-hydroxy-quinolinato) aluminium (Alq3) thin films have been determined using impedance spectroscopy (IS) measurements. The theoretical basis of drift-mobility measurement with IS rests on a theory for single-injection space-charge limited current. The electron drift-mobilities in Alq3 which measured from the frequency dependence of both capacitance and conductance had the same electric-field dependence and were identical to those measured by a time-of-flight (TOF) transient photocurrent technique. To estimate the hole drift-mobility in Alq3, a 4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl thin film was inserted as an injection layer to reduce the hole injection barrier between an injection electrode and the Alq3 thin film. The hole drift-mobilities of Alq3 thin films measured with IS were identical to those measured by the TOF method. These results are essential for clarifying the mechanism of the carrier transport of organic light emitting diodes (OLEDs) with the aim of improving OLED performance.
Journal: Thin Solid Films - Volume 554, 3 March 2014, Pages 213–217