Top-emission AMOLED display driven by organic TFTs with semiconductor layer patterned by inkjet process

We have developed an inkjet process for laying down an organic semiconductor layer in organic thin‐film transistors (OTFTs). The organic semiconductor crystallinity was improved by adjusting the contact angles of the bank, the gate insulator, and the source/drain electrodes. The threshold voltage of the OTFT was controlled by means of several surface treatments of the silicon dioxide gate insulator. The OTFTs showed a high mobility of 2.5 cm2/Vs and uniform threshold voltages of −0.4 ± 0.7 V. We also fabricated a 4‐in., 80‐ppi active‐matrix organic light‐emitting diode on a glass substrate that showed good luminance uniformity and high moving picture quality.