We demonstrated that the supercritical CO2 fluid treatment was a new concept to efficiently reduce the operation current of resistance random access memory. The dangling bonds of tin-doped silicon oxide (Sn:SiOx) thin film were passivated by the hydration-dehydration reaction through supercritical CO2 fluid treatment, which was verified by the XPS and FTIR analyses. The current conduction mechanism of low resistance state in post-treated Sn:SiOx thin film was transferred to hopping conduction from Ohmic conduction. Furthermore, the current conduction mechanism of high resistance state in the memory device was transferred to Schottky emission from Frenkel-Poole conduction. The phenomena were attributed to the discontinuous metal filament formed by hydration-dehydration reaction in Sn:SiOx thin film through supercritical fluid treatment. Finally, a reaction model was proposed to explain the mechanism of current reduction in Sn:SiOx thin film with supercritical CO2 fluid treatment. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.