In the study, we reduced the operation current of resistance random access memory (RRAM) by supercritical CO2 (SCCO2) fluids treatment. The power consumption and joule heating degradation of RRAM device can be improved greatly by SCCO2 treatment. The defect of nickel-doped silicon oxide (Ni:SiOx) was passivated effectively by the supercritical fluid technology. The current conduction of high resistant state in post-treated Ni:SiOx film was transferred to Schottky emission from Frenkel-Pool due to the passivation effect. Additionally, we can demonstrate the passivation mechanism of SCCO2 for Ni:SiOx by material analyses of x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.