Effect of TiCu source/drain on an amorphous IGZO TFT employing SiNx passivation for low data-line resistance

摘要

We successfully fabricated a-IGZO TFTs with a TiCu sourcedrain (SD) in order to reduce the data-line resistance. SiNx passivation was used to protect the Cu from Cu-oxygen diffusion. The TFTs exhibited normal enhancement-mode characteristics compared to the TFT employing a Mo SD, which behaved like a conductor. Our experiments suggest that the TiCu SDs control the channel resistivity of the fabricated TFT lower than the Mo case. We found an indium-deficient IGZO layer under the Ti contact; this is thought to be the origin which reduces oxygen vacancy concentration in the channel.