High-Performance Multilevel Resistive Switching Gadolinium Oxide Memristors With Hydrogen Plasma Immersion Ion Implantation Treatment

Multilevel resistive switching (RS) of gadolinium oxide (GdxOy) memristors treated by hydrogen plasma immersion ion implantation (PIII) was investigated. Hydrogen ions were implanted at the Pt/GdxOy interface to modify the oxygen-vacancy distribution, which was examined by the X-ray photoelectron spectroscopy. After the hydrogen PIII treatment, a forming process is needed to operate the GdxOy memristors and the RS mechanism is changed from Schottky emission to space-charge-limited conduction. Superior multilevel RS properties such as data retention for more than 10(4) s at 85 degrees C, and sequentially cycling test for more than 10(3) times with a resistance ratio of approximately one order of magnitude between each state are realized, making the future high-density flash memory possible.