Paper EM+PS-WeM4
The Effect of High-Pressured N₂ Annealing in NiO_x based Resistive Random Access Memory

Wednesday, October 30, 2013, 9:00 am, Room 102 A

High pressure annealing (HPA) is known as an effective way to control the fundamentals of oxide system through the modification of stoichiometry, thermal decomposition, and compression.[1] Here, we report the effect of N₂ HPA on NiO_x based resistive random access memory (RRAM) device in terms of applied pressures in NiO_x system. In this research, the annealing temperature was fixed at 350 ^oC while the applied pressures were varied to 1, 20, and 50 atm. Pt was commonly used as bottom and top layer of metal-insulator-metal structure. As the N₂ pressure increased, the on- and off- resistance ratio was decreased from ~10⁵ to ~10⁴. However, the operation voltages (reset and set voltage) were reduced followed by increment of N₂ pressure. Specifically, the 50 atm HPA sample shows the lowest reset voltage of 0.95 V and set voltage of 2.12 V. This result implies that enhanced grain size was induced by the N₂ pressure as the grain boundaries are preference sites for conduction filament formation.[2] Furthermore, notable increment of non-lattice oxide component was confirmed which may cause the reduced driving voltages by x-ray photoelectron spectroscopy. These findings can enhance the understanding of low-power driving RRAM for next generation memory device.

References:

[1] Y. S. Rim, W. H. Jeong, D. L. Kim, H. S. Lim, K. M. Kim and H. J. Kim, J. Mater. Chem. 22, 12491 (2012).

[2] S. Kim, D. Lee, J. Park, S. Jung, W. Lee, J. Shin, G. Choi, and H. Hwang, Nanotech. 23, 325702 (2012).