Magnetically assembled 30 nm diameter nickel nanowire with ferromagnetic electrodes

Abstract

Facile, cost-effective, and manufacturable techniques to create single-nanowire baseddevices with good electrical interconnects is demonstrated by combining template directedelectrodeposition, magnetic assembly, and a post-annealing in a reducing environment.Nickel nanowires with a diameter of approximately 30 nm were electrodepositedfrom low-stress nickel sulfamate baths at room temperature using in-house madeanodized alumina as a nanotemplate. After electrodeposition, nanowires werereleased from the template, efficiently positioned, trapped, and assembled onferromagnetic electrodes using the magnetic interaction between the nanowiresand the electrodes. By annealing the interconnect in a reducing environment of5%H2+95%N2 at300 °C for 30 min, the interconnect’s resistance was dramatically reduced from>10 M Ω to835 Ω. Magnetotransport studies at 300 K on a single nickel interconnect with diameters rangingfrom 30 to 200 nm show a strong diameter dependent magnetoresistance, which might beattributed to different domain structure within the interconnect.