Material and Electrical Properties of Hole-Trapping Memory Capacitors Composed of nc-ITO Embedded ZrHfO High-k Films

The material and electrical properties of MOS memory capacitors composed of single- and dual-layer nc-ITO embedded ZrHfO high-k films have been investigated. The dual-layer nc-ITO embedded sample shows a higher charge trapping density than the single-layer nc-ITO embedded sample does. The formation of an interface layer at the nc-ITO and ZrHfO contact region is confirmed by XPS analysis. The memory function is mainly based on trapping holes at both the bulk and interface of the nc-ITO site. The frequency-dependent C-V and G-V results indicate that parts of holes are loosely trapped at the nc-ITO/ZrHfO interfaces. The hole-trapping and -detrapping phenomena are also confirmed from the J-V measurements.