Effect of the Electrode Materials on the Drain-Bias Stress Instabilities of In鈥揋a鈥揨n鈥揙 Thin-Film Transistors

详细信息    查看全文

• 作者：Jun Yong Bak ; Sinhyuk Yang ; Min Ki Ryu ; Sang Hee Ko Park ; Chi Sun Hwang ; Sung Min Yoon
• 刊名：ACS Applied Materials & Interfaces
• 出版年：2012
• 出版时间：October 24, 2012
• 年：2012
• 卷：4
• 期：10
• 页码：5369-5374
• 全文大小：377K
• 年卷期：v.4,no.10(October 24, 2012)
• ISSN：1944-8252

文摘

The effects of electrode materials on the device stabilities of In鈥揋a鈥揨n鈥揙 (IGZO) thin-film transistors (TFTs) were investigated under gate- and/or drain-bias stress conditions. The fabricated IGZO TFTs with a top-gate bottom-contact structure exhibited very similar transfer characteristics between the devices using indium鈥搕in oxide (ITO) and titanium electrodes. Typical values of the mobility and threshold voltage of each device were obtained as 13.4 cm² V^鈥? s^鈥? and 0.72 V (ITO device) and 13.8 cm² V^鈥? s^鈥? and 0.66 V (titanium device). Even though the stabilities examined under negative and positive gate-bias stresses showed no degradation for both devices, the instabilities caused by the drain-bias stress were significantly dependent on the types of electrode materials. The negative shifts of the threshold voltage for the ITO and titanium devices after the 10⁴-s-long drain-bias stress were estimated as 2.06 and 0.96 V, respectively. Superior characteristics of the device using titanium electrodes after a higher temperature annealing process were suggested to originate from the formation of a self-limiting barrier layer at interfaces by nanoscale observations using transmission electron microscopy.

Keywords:

oxide semiconductor; thin-film transistor; device reliability; bias stress; electrode; In鈭扜a鈭抁n鈭扥