Electrical Wind Force–Driven and Dislocation-Templated Amorphization in Phase-Change Nanowires

• DOI: 10.1126/science.1220119
• Publication Date: 2012-06-21T23:53:18Z
• Authors: Sung-Wook Nam; Hee-Suk Chung; Yu Chieh Lo; Liang Qi; Ju Li; Ye Lu; A.T. Charlie Johnson; Yeonwoong Jung; Pavan Nukala; Ritesh Agarwal
• Keywords: 02 engineering and technology; 0210 nano-technology

Exploiting Defects in a Jam

Phase-change materials that can readily switch between crystalline and amorphous states are increasingly finding use in nonvolatile memory devices (see the Perspective by

Hewak and Gholipour

). Using high-resolution transmission electron microscopy,

Nam et al.

(p. 1561 ) show that for Ge 2 Sb 2 Te 5 , the application of an electric field drives crystal dislocations in one direction, leading to their accumulation and eventual jamming, which causes the phase transition.

Loke et al.

(p. 1566 ) found that by applying a constant low voltage to Ge 2 Sb 2 Te 5 , they could accelerate its phase-switching speeds, without harming the long-term stability of the switched state.