Abstract
A complementary metal oxide semiconductor (CMOS)-compatible WO <sub>x</sub> based resistive memory has been developed. The WO <sub>x</sub> memory layer is made from rapid thermal oxidation of W plugs. The device performs excellent electrical properties. The switching speed is extremely fast (∼2 ns) and the programming voltage (<1:4 V) is low. For single-level cell (SLC) operation, the device shows a large resistance window, and 10 <sup>8</sup> -cycle endurance. For multi-level cell (MLC) operation, it demonstrates 2-bit/cell storage with the endurance up to 10000 times. The rapid thermal oxidation (RTO) WO <sub>x</sub> resistance random access memory (RRAM) is very promising for both high-density and embedded memory applications. © 2010 The Japan Society of Applied Physics.