Nanocomposite Phase-Change Memory Alloys for Very High Temperature Data Retention

Phase-change memory alloys based on germanium, antimony, and tellurium with SiO₂ nanophase dielectric inclusions are investigated for material and electrical properties. The new alloys are prepared by cosputtering with a SiO₂ target creating nanophase dielectric inclusions. The addition of the dielectric inclusions significantly increases the crystallization temperature without affecting the required programming current. In memory device configurations, the nanocomposite alloys exhibit a ten-year data retention above 200°C and a cycle life greater than 1 × 10⁷ cycles while maintaining the SET programming speed of 250 ns.