Magnetically assembled 30 nm diameter nickel nanowire with ferromagnetic electrodes

Abstract

Facile, cost-effective, and manufacturable techniques to create single-nanowire based devices with good electrical interconnects is demonstrated by combining template directed electrodeposition, magnetic assembly, and a post-annealing in a reducing environment. Nickel nanowires with a diameter of approximately 30 nm were electrodeposited from low-stress nickel sulfamate baths at room temperature using in-house made anodized alumina as a nanotemplate. After electrodeposition, nanowires were released from the template, efficiently positioned, trapped, and assembled on ferromagnetic electrodes using the magnetic interaction between the nanowires and the electrodes. By annealing the interconnect in a reducing environment of 5%H(2)+95%N(2) at 300 °C for 30 min, the interconnect's resistance was dramatically reduced from >10 M Ω to 835 Ω. Magnetotransport studies at 300 K on a single nickel interconnect with diameters ranging from 30 to 200 nm show a strong diameter dependent magnetoresistance, which might be attributed to different domain structure within the interconnect.