Investigation on the role of nitrogen in crystallization of Sb-rich phase change materials

Abstract

To better understand the role of nitrogen (N) during crystallization of Sb-rich phase change materials, a study was conducted using Sb and Sb(70)Te(30) as host materials of N. Crystallization of the as-sputtered Sb-N films of varying N content was examined to reveal that Sb-N bonds are formed in the as-sputtered states, enhancing amorphous phase stability increasingly with N content. Crystallization appeared to proceed with irreversible dissociation of these bonds to form N(2) molecules that may then exist stably during the subsequent memory operations. N(2) molecules are considered to play as growth-retarding agents as demonstrated with memory operations of N-doped Sb(70)Te(30).