Nanoscale mechanically induced structural and electrical changes in Ge 2Sb 2Te 5 films

Abstract

We demonstrate that the microstructure and electrical properties of Ge 2Sb 2Te 5 films can be changed by a nanoscale mechanical process. Nanoscratching is used to define modified areas onto an as-deposited crystalline Ge 2Sb 2Te 5 film. Scanning tunneling microscopy measurements show that the modified areas have a very low electrical conductivity. Micro-Raman measurements indicate that the mechanically induced microstructural changes are consistent with a phase transformation from crystalline to amorphous, which can be reversed by laser irradiation.