Study on the Electrical Current Mechanism of Organic Thin Film Device

For organic thin film devices(OTFD),such as organic light-emitting diode(OLED) and organic thin film triode(OTFT),the electrical current mechanism of devices governs the performance of devices,as a result,it is inevitable to understand the relative theory.Although there have already been lots of reports on electrical performance of OTFD,the results of them deviate from each other due to the complexity of device structure and internal mechanism of organic thin film.In this study,by using magnesium-silver alloy(MgAg) as both electrodes and 8-hydroxy quinoline aluminum(Alq3),which was widely applied as electron transporter and light-emitter,as organic functional layer,electrical current mechanism of sandwich device of MgAg/Alq3/MgAg was studied.The measured and fit results indicate that the device is electron-only device,whilst device current obeys trapped charge limited current(TCLC) mechanism.In addition,device current increases with the increase of temperature,which is attributed to the fact that the concentration and mobility of carriers have an exponential relation with negative reciprocal of temperature.