Bias-stress trapping

Fig. 5.1. Example of successive transfer curves obtained if bias stress is due to charge trapping in immobile states (a) and if bias stress is due to the formation of shallow donor-like states...

The recovery rate of the reversible traps determines the duty-cycle cut-off below which only long-lived traps contribute to bias stress. At higher duty cycle, the current decay is the result of the simultaneous interplay of fast and slow trapping. 

FIGURE 3.19. J-V characteristics taken at various times for a device stressed at 150 /xA/cm2. Successive curves begin to deviate from the original at about 3 Y and then reconverge to the same square-law behavior at higher bias. This corresponds qualitatively to the simulations where traps are generated —0.25 eY below the Alq3 LUMO, shown by the solid curves. 

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