Self-assembled Bi interconnections produced by on-film formation of nanowires for in situ device fabrication

We fabricated Bi nanowire interconnections between two pre-patterned electrodes using a combination of on-film formation of nanowires (OFF-ON) and self-assembly. Bi nanowires were found to grow laterally from a multilayer structure with a Cr (or SiO₂) overlayer on top of a Bi thin film through thermal annealing to relieve vertically stored compressive stress. A Bi nanobridge with a diameter of 192 nm was formed between two Cr electrodes and was highly ohmic according to I-V measurements. A high transverse magnetoresistance of 123% was also observed at 300K. Our results indicate that self-assembled lateral nanowire growth can be utilized as an easy means for fabricating a variety of nanowire devices without the use of catalysts or complex patterning processes.