One Gate Diode-Connected Dual-Gate a-IGZO TFT Driven Pixel Circuit for Active Matrix Organic Light-Emitting Diode Displays

摘要

A dual-gate (DG) amorphous indium-gallium- zinc-oxide thin-film transistor (TFT)-driven pixel circuit for active-matrix organic light-emitting diode displays is presented. One gate of the DGs serves as a primary gate (PG) and the other as an auxiliary gate (AG). The threshold voltage (VTH) of the DG TFT under the PG operation is modulated by the AG bias voltage. The VTH variation (ΔVTH) is compensated with the AG and the drain diode-connected structure. The validity of the presented pixel circuit is experimentally verified. The measured current error rates are less than 3.2% at a ΔVTH of TFT = ±0.5 V and a ΔVTH of OLED = 0.5 V with the emission current ranging from 7 nA to 1.13 μA.