Charge transport mechanism of high-resistive state in RRAM based on SiO<i>x</i>

Abstract

Nonstoichiometric silicon oxide SiOx is a promising material for developing a new generation of high-speed, reliable flash memory based on the resistive effect. It is necessary to understand the electron transport mechanism of the high-resistive state in SiOx to develop a resistive memory element. At present, it is generally accepted that the charge transport of the high-resistive state in the Resistive Random Access Memory (RRAM) is described by the Frenkel effect. In our work, the charge transport of the high-resistive state in RRAM based on SiOx is analyzed with two contact-limited and five volume-limited charge transport models. It is established that the Schottky effect model, thermally assisted tunneling, the Frenkel model of Coulomb trap ionization, the Makram-Ebeid and Lannoo model of multiphonon isolated trap ionization, and the Nasyrov-Gritsenko model of phonon-assisted tunneling between traps, quantitatively, do not describe the charge transport of the high-resistive state in the RRAM based on SiOx. The Shklovskii-Efros percolation model gives a consistent explanation for the charge transport of the high-resistive state in the RRAM based on SiOx at temperatures above room temperature.