Yi-Kai Wang

A 5" active-matrix electrophoretic panel driven by organic TFTs

We successfully fabricated 5-inch organic thin film transistors array with 320×240 pixels on flexible substrate. All the processes were done by photolithography, spin coating and ink-jet printing. The OTFT-Electrophoretic (EP) pixel structure, based on a top gate OTFT, was fabricated. The mobility, ON/OFF ratio, subthreshold swing and threshold voltage of OTFT on flexible substrate are: 0.01 cm2/V-s, 1.3 V/dec, 10E5 and -3.5 V. After laminated the EP media on OTFT array, a panel of 5 inch 320×240 OTFT-EPD was fabricated. All of process temperature in 10×10 OTFT-EPD is lower than 150 . The pixel size in our panel is 300 μm × 300 μm, and the aperture ratio is 50 %. The OTFT channel length and width is 20 μm and 200μm, respectively. We also used OTFT to drive EP media successfully. The operation voltages that are used on the gate bias are -30 V during the row data selection and the gate bias are 0 V during the row data hold time. The data voltages that are used on the source bias are -20 V, 0 V, and 20 V during display media operation.