Low Angle Annular Dark Field Scanning Transmission Electron Microscopy Analysis of Phase Change Material

Abstract

The continuously growing demands in high-density memories drive the rapid development of advanced memory technologies. In this work, we investigate the mushroom type PCM cells based on Ge2Sb2Te5 at nanoscale by low angle annular dark field (LAADF) STEM imaging technique as well as energy dispersive X-ray spectroscopy (EDX) to study the changes in microstructure and elemental distributions in PCM mushroom cells before and after SET and RESET conditions. We describe the microscope settings used for LAADF image formation to reveal the amorphous dome in RESET device and discuss the application example in failure analysis of PCM test device.