The Transient Electroluminescent Measurement Applied In Different OLED Luminescence Mechanisms

Organic electroluminescent glow as a new kind of technology is more and more people understand and use, a variety of physical, more and more into peop le’s lives.In the past few decades, with a luminescent material optimization, opti mization of the device structure and preparation process of the reform, luminesce nce properties of organic electroluminescent devices have a lot of ascension, but the light emitting mechanism of organic electroluminescent has also does not hav e a unified theory, so the researches on the mechanism of the organic electrolum inescent devices within also appears more and more important.Based on above all, this paper has done the following works:ITO/PEDOT:PSS/m-MTDATA (20nm)/m-MTDATA:3tpymb (1:1,40nm)/3tpymb (20nm)/LiF (0.8nm)/Al (80nm) of the device, and use the tra nsient electroluminescent measurement system to measure its electronic luminous, measuring pulse for the two drive pulse of periodic, two pulse interval of100us,300us and500us.The study found that in the second pulse device driven b y the intensity of EL stable value than the value of the first drive driven by EL strength stability, and the second pulse intensity of EL stable value and the rati o of the value of the first pulse EL intensity stability decreases with increasing t hrough the device of the current, the experiment also found that the second puls e to cancel delay light attenuation speed faster than the first impulse cancellation, this is because the second pulse to cancel the light-emitting layer in polaron (c harge) quenching of exciton (TPQ) serious.The preparation of the device structure of ITO/Alq3,80,90,100(70nm)/Al (80nm);ITO/Alq3(10nm)/Bphen20,30,40(nm)/Al (80nm);10,20,30,40ITO/NPB (nm)/Alq3(20nm)/LiF/Al (80nm) of the three groups of basic devices.Using tr ansient electroluminescent measurement system for measuring, the study found th at under the same current density, electron transport layer thickness in, the greate r the shorter the time required to stabilize the emitting, this is because to achiev e the same current density, the thickness of the device, the greater the need of t he higher the voltage, high voltage can improve the ability of the injection of el ectrons and holes, so on light-emitting device to achieve stable luminous time pl ayed a role.The preparation of the device structure of ITO/PEDOT/TAZ:IrO10%(wt)/L iF/Al of a set of devices, including light-emitting layer adopts jilt membrane pre pared, sling film speed1500r/min respectively,2000r/min and2500r/min and3000r/min.Experiment found that the device steady luminescence spectra, with hi gher driving voltage, light shoulder peak is more and more high, this is because the light emitting layer of more intense internal TPQ therefore lower energy att enuation of exciton emitting occupy more luminous elements, cause the change o f the luminous shoulder peak.Using transient electroluminescent measurement syst em for measuring, found that there was a luminous overshoot phenomenon, drive to cancel this is due to the accumulation in the light-emitting layer on both sid es of the electrons and holes caused by recombination luminescence.