Designing Sb phase change materials by alloying with Ga2S3 towards high thermal stability and low resistance drift by bond reconfigurations

The pure Sb phase-change thin films alloyed with Ga2S3 alloy have been prepared and the related properties have been investigated. Compared with pure Sb, Ga2S3-alloyed Sb films exhibit higher crystallization temperature (-250 degrees C), larger ten-year data retention temperature (-166 degrees C), and higher crystallization activation energy (4.10 eV). These thermal parameters indicate that the thermal stability of the Ga2S3- alloyed Sb thin films can be considerably enhanced due to the formation of high binding energy Sb-S and Sb-Ga bonds. Moreover, the enhanced thermal stability can also significantly lower resistance drift coeffi-cient (0.0014). According to the analysis of the crystallization mechanism, the crystallization kinetic index (n) is determined to be 0.625, implying one-dimensional growth type in Ga2S3-alloyed Sb thin films. This can benefit to reduce the nucleation randomness and decrease resistance drift. The work demonstrates that Ga2S3-alloyed Sb materials have excellent potential for embedded memory applications. (c) 2023 Elsevier B.V. All rights reserved.