Interface engineering for improving reliability of resistance switching in Cu/HfO2/TiO2/Pt structure

• DOI: 10.1063/1.4928710
• Publication Date: 2015-08-17T17:00:27Z
• Authors: Li Wei Zhou; Xing Long Shao; Xiang Yuan Li; Hao Jiang; Ran Chen; Kyung Jean Yoon; Hae Jin Kim; Kailiang Zhang; Jinshi Zhao; Cheol Seong Hwang
• Keywords: 02 engineering and technology; 0210 nano-technology

Reliability and uniformity in resistance switching behaviours in top electrode Cu-sputtered TiO2-bottom electrode Pt memory structure were greatly improved by inserting an interface layer of 5 nm-thick HfO2 between Cu and 50 nm-thick TiO2. The thin HfO2 layer, with much smaller cluster size than TiO2, limited the Cu migration appropriately and induced more uniform Cu conducting filament distribution. The repeated rejuvenation and rupture of Cu filament was limited within the HfO2 layer, thereby improving the switching reliability and uniformity. This also greatly decreased operation power compared to a memory cell without the thin HfO2 layer.