Emerging oxide resistance change memories

Abstract

The state of the art in resistance-based memory technology is presented. Recently memory technology has been focused on convergence towards ubiquitous memories which are non-volatile, have random access, and have fast programming times. This chapter is focused on electrically induced resistive change memories (including the resistive switching materials and mechanism) and other applications. Resistive random access memory (RRAM) has the simplest structure of new memory technologies, in fact the resistance change phenomenon can be observed in a metal-insulator-metal structure. Also, the switching speed has been reported to be about 10 ns and the resistance change effect scales down to cell sizes of 10 × 10 nm2 [1, 2]. First, we review classification of resistance memory and materials: unipolar, bipolar, ionic, and electronic effect memory. The second section deals with structure of cell stack architecture, which is a very important merit of resistance memories in particular, RRAM cell scaling and RRAM integration. In the final section the superior intrinsic scaling characteristics of RRAM compared to charge-based devices, and multilevel cell (MLC) RRAM, are discussed. Finally, we conclude with some comments on the outlook, future works, and research necessary for realization of RRAM technology.