Superlattice-like SnSb4/Ge thin films for ultra-high speed phase change memory applications

Abstract

Superlattice-like (SLL) SnSb₄/Ge thin films were studied by thermal, electrical and optical methods. It was found that SnSb₄ (SS) films composited with Ge in a superlattice-like configuration showed better thermal stability. With composited Ge, the temperature of 10-year data retention increased from 54 °C to 139 °C. In the electrical studies, reversible transition of a phase change memory cell based on [SS (8 nm)/Ge (4 nm)]₄ could be achieved by using an electrical pulse as short as 500 ns. Moreover, ultrafast crystallization (∼6.54 ns at a energy density of ∼4.47 mJ cm⁻²) in the [SS (8 nm)/Ge (4 nm)]₄ film was confirmed, which was essential to achieve rapid data recording in phase change memory.