Enhancing Ga─Sb Bonds by GaSb Co-Doping Ge2Sb2Te5 for High Speed and Thermal Stability Phase Change Memory

Abstract

Chalcogenide phase change memory, a next-generation non-volatile memory technology, holds significant promise in neuromorphic computing, leading to an urgent demand for high-performance phase change materials. However, in the realm of phase change materials, there appears to be an inherent contradiction between enhancing crystallization speed and bolstering amorphous stability. In this work, the formation of Ga─Ge bonds associated with Ga single doping are effectively addressed through the deliberate incorporation of GaSb co-doping. This strategic approach to bonding variety has significantly improved operational speed to a remarkable 8 ns, the crystallization temperature is elevated to 196 °C, and multilevel phase change performance is retained. First-principles calculations and material characterization is conducted to elucidate the underlying mechanisms responsible for the observed enhancements in both thermal stability and operation speed. This investigation provides valuable insights for optimizing the performance of phase change materials and addresses the pressing challenge of integrating phase change materials into a neuromorphic computing system.