Minority carrier lifetime of thermal degradation in organic light emitting diode

Lifetime is one of the most important parameter that it is implied many information of device electrical characteristics directly. It can be estimated to using the degradation of luminance with accelerating the charge supply in the traditional method of display devices lifetime analyzing. It takes great deal of time and a lot of effort to measure the lifetime according to degradation effects. This plot reveals that minority carrier lifetime is dominant in the entire device life of organic light emitting diode (OLED). Forward current (I_F) measured before switching, reverse current (I_R) after switching, storage time (t_s) and reverse recovery time (t_rr) were measured by transient response to drive minority carrier lifetime (τ_p). The device minority carrier lifetime 90ns and 121ns extracted from transient equation and 9μs to 12μs average storage time is obtained in RGB OLEDs, respectively. We have reported that comparing the minority carrier lifetime characteristics of OLED with red, green and blue general diode, the color emission material induced device lowering through the carrier behavior. Ultimately, using the optical measurement including luminance transition and whole lifetime, carrier lifetime correlated with degradation is elicited in this paper.