Integrated Active-Matrix Capacitive Sensor Using a-IGZO TFTs for AMOLED

We report a capacitive touch sensor using a-IGZO TFTs as active components to improve touch sensitivity and output robustness. The output potential difference between touched/untouched states is 1.7 V without readout buffer. Additionally, due to the fully compatible gate driving clocks with conventional active-matrix backplane, the integration of the capacitive touch sensor with AMOLED display without additional driver ICs can be realized. An 8 × 8 array with only one output pin using pixel-by-pixel readout has been developed, which benefits the full flexible applications with simple connection and readout method.