Investigation of Sb65Se35/Sb multilayer thin films for high speed and high thermal stability application in phase change memory

Abstract

Sb65Se35/Sb multilayer composite thin films were prepared by depositing the Sb65Se35 and Sb layers alternately. In situ resistance vs. temperature was measured and the crystallization temperature increased with thickening the Sb65Se35 layer in Sb65Se35/Sb thin films. The data retention temperature of 10 years increased greatly from 14 °C of pure Sb to 103 °C of [Sb65Se35(3 nm)/Sb(7 nm)]3. Also, the band gap was broadened and the surface became smoother. X-ray diffraction patterns for the studied materials revealed that Sb and Sb2Se3 phases coexisted in Sb65Se35/Sb thin films. Absorbing the advantages of the fast phase change for Sb, the [Sb65Se35(1 nm)/Sb(9 nm)]5 multilayer thin film had an ultrafast amorphization speed of 1.6 ns. The results indicated that Sb65Se35/Sb multilayer thin film was a potential phase change material for fast speed and good stability.