Failure analysis of pixel shorting problems in polymer light emitting diode (PLED) displays

A failure analysis process, combining electrical characterization, optical microscopy, SEM/FIB, and other analytical methods, to identify the root cause of pixel shorts in polymer light emitting diode (PLED) displays is presented. Shorted pixels appear black on a full-on white screen, influencing the display uniformity; they could also cause driver problems by drawing excess current. Pixel shorting also poses a reliability problem, since it can occur after burn-in, during the lifetime of the display. The paper discusses the FA process and identified failure mechanisms.