The electrical characteristics of the BCE-structure IGZO TFTs were studied. Through modifying the passivation layer and optimizing the selection of copper acid and PFA material, the TFTs exhibited good threshold voltage and reliability. Finally, a high performance 31-inch 8K4K GOA LCD was demonstrated.

Abstract

Illumination instability of BCE IGZO TFT was studied in this paper. It was found that the distance between island‐in IGZO and gate electrode is larger than 2μm (P2) could be able to resist light induced device deterioration effectively. We also found that P4 was an optimum distance for flicker performance compared to P2 design, the flicker level of P2 and P4 is 25dB and HdB respectively. Finally, a high performance 32‐inch 8K4K IGZO LCD was successfully demonstrated based on all the study above.

We successively fabricated 1G1D 85″ 8K4K 120Hz LCD with oxide TFT using only four‐mask array process. The transmittance and contrast ratio of our 85″ panel are 4.5% and 5000, which show 8% and 15% improvement than a‐Si TFT counterparts. The power consumption is reduced 20% compared to a‐Si TFT panels.

Due to the low resistance and excellent glass adhesion, Cu/Mo dual-layer metal wire has been widely used in TFT-LCD industry. However, the galvanic reaction between the two metals, which may be the main cause of metal corrosion and diffusion in some failure TFT devices, has been seldom reported.According to the detailed study of the wet and rinse process, this work proposes a possible corrosion mechanism.