A multi-Vth a-IGZO TFT technology using anodization to selectively reduce oxygen vacancy concentration in channel regions

作者：He Xin; Xiao Xiang; Shao Yang; Deng Wei; Leng Chuanli; Zhang Shengdong

来源：IEEE Electron Device Letters, 2014, 35(12): 1248-1250.

DOI：10.1109/LED.2014.2359931

• a-IGZO
• Amorphous indium gallium zinc oxides (a igzo)
• Anodization voltages
• C. thin film transistor (TFT)
• Enhancement modes
• Oxygen vacancy concentration
• Reduction of oxygen
• TFT

A multithreshold voltage amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) technology based on the anodic oxidation (anodization) technique is demonstrated. It is shown that the characteristics of the a-IGZO channel layer can be considerably tailored by the anodization treatment. As a result, the threshold voltage of the a-IGZO TFTs depends on the anodization voltage, making it possible to fabricate both depletion and enhancement mode TFTs on the same substrate. The secondary ion mass spectrometry result shows that the oxygen content is noticeably increased in the anodized a-IGZO film, suggesting that the dependence of the threshold voltage on the anodization treatment is attributed to the anodization-induced reduction of oxygen vacancy concentration in the channel region, which also leads to an alleviated Vthshift under negative bias illumination stress in the anodized devices.

• 出版日期2014
• 单位北京大学