Characterization of gadolinium oxide thin films with CF4 plasma treatment for resistive switching memory applications

Abstract The effect of the CF 4 plasma treatment on the gadolinium oxide (Gd x O y ) thin films for the resistive random access memory (RRAM) applications was investigated. The material properties of the fluorine incorporated Gd x O y films were analyzed by the X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and ultraviolet–visible spectroscopy (UV–VIS). Further, the set and reset voltages of the Pt/Gd x O y /W RRAM devices with the CF 4 plasma treatment were effectively reduced to −1.15 and 2.1 V respectively owing to the low Schottky barrier height. The formation of Gd F bonds can prevent the oxygen atoms from out-diffusing through Pt grain boundaries into the atmosphere, leading to the superior retention characteristics for over 10 4  s. The CF 4 plasma treated Gd x O y RRAMs can sustain a resistance ratio of 10 2 for more than 800 times stable set/reset cycling, suitable for future low-voltage and high-performance nonvolatile memory operation.