In this paper, a novel chemical soak method is proposed to fabricate a Cu-doped SiO 2 ReRAM device. This method can easily fabricate a lightly Cu-doped SiO 2 film and effectively improve the reliability of the conventional Cu-doped SiO 2 ReRAM device. A reproducible bipolar switching characteristic with set/reset voltage (ca. 2.5 V/ -0.7 V) is performed in this device and the electrical conduction in HRS and LRS are related to Poole-Frenkel and Ohmic conduction, respectively. Excellent performance in terms of high on/off ratio (∼10 6), narrow range distribution of set and reset voltages, stable data retention, and up to 110 times switching cycles has been achieved by this novel chemical soak method for Cu-doped SiO 2 ReRAM device.