In-process functional testing of pixel circuit in AM-OLEDs

This paper presents a functional testing scheme using a two-thin-film-transistor (TFT) pixel circuit of an active-matrix organic light-emitting display (AM-OLED). This pixel circuit and the co-operative electrical testing scheme can not only evaluate the characteristics of each TFT, but also determine the location of line and point defects in the TFT array. Information on defects can be used in a unique repair system that cutting and repairing these defects. Furthermore, the functional testing scheme can be applied as a part of yield management of the AM-OLED array process.