P‐50: Effects of Fabrication Process Variation on the Operation of OLED Pixel Circuit

Non‐uniform parasitic capacitance at the storage node of OLED pixel circuit varies the gate‐to‐source voltage of driving transistor and therefore leads to brightness variation. Both the charging speed of the capacitance during threshold voltage compensation and the capacitive coupling effects from switching signal lines can be different due to the parasitic capacitance variation. We report how the parasitic capacitance varies due to overlay misalignment and line width deviation during the fabrication process. We also report how the capacitance variation affects the emission current of OLED pixel.