Young's modulus and residual stress of GeSbTe phase-change thin films

• We deposited amorphous Ge1Sb2Te4 and Ge2Sb2Te5 phase change thin films on microcantilevers.
• Upon annealing, the films crystallized, leading to a change in cantilever resonance frequency.
• From this change, we determined the change in Young's modulus and residual stress.

The mechanical properties of phase change materials alter when the phase is transformed. In this paper, we report on experiments that determine the change in crucial parameters such as Young's modulus and residual stress for two of the most widely employed compositions of phase change films, Ge1Sb2Te4 and Ge2Sb2Te5, using an accurate microcantilever methodology. The results support understanding of the exact mechanisms that account for the phase transition, especially with regard to stress, which leads to drift in non-volatile data storage. Moreover, detailed information on the change in mechanical properties will enable the design of novel low-power nonvolatile MEMS.