Formation of arsenic clusters in InAs nanowires with an Al₂O₃shell

An in-depth understanding of thermal behavior and phase evolution is required to apply heterostructured nanowires (NWs) in real devices. The intermediate status during the vaporization process of InAs NWs in an Al₂O₃shell was studied by conducting quenching duringin situheating experiments, using a transmission electron microscope. The formation of As clusters in the amorphous Al₂O₃shell was confirmed by analyzing the high-angle annular dark field images and energy-dispersive X-ray spectra. The As clusters existed independently in the shell and were also observed at the end of the InAs pieces obtained after quenching. The formation process of the As clusters was demonstrated from a theoretical perspective. Moreover, anab initiomolecular dynamics simulation (AIMD) was conducted to study the atomic and molecular behaviors.