Highly uniform and reliable resistance switching properties in bilayer WO x /NbO x RRAM devices

• Published in: Physica status solidi. A, Applications and materials science Vol. 209; no. 6; pp. 1179 - 1183
• Main Authors: Sadaf, Sharif Md, Liu, Xinjun, Son, Myungwoo, Park, Sangsu, Choudhury, Sakeb H., Cha, Euijun, Siddik, Manzar, Shin, Jungho, Hwang, Hyunsang
• Format: Journal Article
• Language: English
• Published: 01.06.2012
• ISSN: 1862-6300; 1862-6319
• DOI: 10.1002/pssa.201127659

Abstract Memory performances, especially uniformity and reliability of resistance random access memory (RRAM) devices with W/NbO x /Pt structures were investigated. Scaling down the active device area ( ø  = 250 nm) can significantly minimize extrinsic defects related to nonuniform switching and also demonstrate low‐voltage SET/RESET operations due to increased Joule heating. Electromigration of oxygen ions under the bipolar electric field, bilayer formation, and lightning‐rod effect localized at WO x /NbO x interface can explain the improved switching behavior in this novel stack. Excellent device characteristics such as lower switching voltage, fast switching speed (100 ns), high‐temperature retention (>10 4  s, 85 °C), stable cycling endurance (10 7 cycles), almost 100% device yield and excellent switching uniformity are obtained.