On the Key Impact of Composition of Ge-Te and Ge-Se Electrolytes on CBRAM Properties

Chalcogenides are interesting as CBRAM electrolytes due to large memory window ranging over 3 orders of magnitude. However, switching time and LRS retention are reliability concerns in these electrolytes. To identify pathways to improve reliability, we evaluate CBRAM devices with different compositions of two chalcogenide electrolytes (Ge-Te and Ge-Se) and investigate the role of chalcogen element and its proportion on the switching and retention characteristics. We find that Ge-Se requires longer SET times and shows better retention than Ge-Te. We also observe an anticorrelation between SET time and the proportion of chalcogen element in these electrolyte systems. Plausible mechanisms which may contribute to these results are also investigated.