Demonstration of GaAsSb/InAs nanowire backward diodes grown using position-controlled vapor–liquid–solid method

Abstract

p-GaAsSb/n-InAs type-II nanowire (NW) diodes were fabricated using the position-controlled vapor–liquid–solid growth method. InAs and GaAsSb NW segments were grown vertically on GaAs(111)B substrates with the assistance of Au catalysts. Transmission electron microscopy-energy-dispersive X-ray spectroscopy analysis revealed that the GaAsSb segments have an Sb content of 40%, which is sufficient to form a tunnel heterostructure. Scanning capacitance microscope images clearly indicated the formation of a p–n junction in the NWs. Backward diode characteristics, that is, current flow toward negative bias originating from a tunnel current and current suppression toward positive bias by a heterobarrier, were demonstrated.