The goal of this project was to initially re-establish a baseline process for the fabrication of Indium-Gallium-Zinc Oxide thin-film transistors, shown in Figure 1, that have been a part of ongoing research here at RIT. After bringing the fabricated devices back into a reliable process, capping layer differences were investigated to determine their effects on device thermal stability. The time of the passivation layer anneal was varied between 3 and 4 hours for the primary lot and the temperature of the ALD capping layer was varied between 150°C and 200°C. The devices were tested and then thermally stressed on a hot plate for an hour at 140°C and 200°C. From the initial testing, it was shown that devices with 200°C ALD and with a 3 hour anneal had the best performance were the most thermally stable. After testing I-V characteristics, a length dependency was also found from the thermal stability in which the shorter devices remained operational after stress, whereas, longer devices became short circuits.
"Capping Layers for Increased Thermal Stability of IGZO Thin-Film Transistors,"
Journal of the Microelectronic Engineering Conference: Vol. 25
, Article 14.
Available at: https://scholarworks.rit.edu/ritamec/vol25/iss1/14