Enhanced reliability of phase-change memory modulation of local structure and chemical bonding by incorporating carbon in GeSbTe.

In this study, we investigated the effect of phase-change characteristics on the device performance of carbon-incorporated GeSbTe (CGST) to understand the origin of the enhanced reliability and stabilization of the device. Macroscopic and microscopic measurements confirmed that the structural stability significantly increased with the incorporation of as much as 10% carbon. After the completion of bond formation between C and Ge, the excess C (>5 atomic%) engages in bonding with Sb in localized regions because of the difference in formation energy.