Investigation on the current nonuniformity in current-mode TFT active-matrix display pixel circuitry

Detailed analysis of the mechanisms that cause deviations of the emission current from the input data current in polycrystalline silicon (poly-Si) thin-film transistor (TFT) current-copier active matrix carbon nanotube field emission display (FED) pixel circuits is presented. These effects make the modulated emission current sensitive to the process variations of the circuit elements. Monte Carlo circuit analysis with a Gaussian statistical distribution of all related process parameters in the pixel circuit shows the emission current nonuniformity, and therefore illustrates the importance of improving the poly-Si TFT process for the design of high-resolution and high-brightness current-mode active matrix addressed displays. The analysis is also suitable for design and optimization of other reported current-mode active matrix addressed FED or organic light-emitting displays.