Improved Retention Characteristics of Pd-Nanocrystal-Based Nonvolatile Memories by a Simple Timing Technique

By controlling the different initial time of Hf and Al precursor supply, the proposed HfxAlyOz tunneling layer with different Al/Hf ratios from 0.21 (top) to 0.06 (bottom) can be fabricated. Regarding Al/SiO2/Pd nanocrystals/proposed HfxAlyOz/Si, the proposed HfxAlyOz film can prevent stress from Pd nanocrystals and achieve a higher electron current during programming. Regarding the retention characteristics, the final memory windows of 2.5/2.05 V at 25/90◦C can be obtained, respectively. Programmed and erased with ±10 V/100 ms, the device shows a memory window of 2.4 V after 104 cycles for a 25◦C test. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/2.0071512ssl] All rights reserved.