This study examined the degradation of the device performance of InGaZnO4 (IGZO)-based thin-film transistors after annealing at high temperatures in air ambient. Using various characterization methods including scanning electron microscopy, x-ray diffraction, and transmission electron microscopy, we were able to disclose the details of a two-stage phase transformation that led to the device performance degradation. The Mo electrodes first succumbed to oxidation at moderate temperatures (400-500 °C) and then the Mo oxide further reacted with IGZO to produce an In-Mo-O compound with some Ga at higher temperatures (600-700 °C). We analyzed our results based on the thermodynamics and kinetics data available in the literature and confirmed that our findings are in agreement with the experimental results.
Bibliographical noteFunding Information:
This work was supported in part by the Ministry of Knowledge Economy (MKE) and the Korea Institute for Advancement of Technology (KIAT) through the Human Resource Training Project for Strategic Technology. This work was also supported in part by the World Class University program of National Research Foundation of Korea (Grant No. R32-2008-000-10124-0).
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering