A Novel Growth Method of Single-Crystalline Bi Nanowires

Abstract

A novel growth method of single-crystalline bismuth (Bi) nanowires is presented. It is found that the growth of Bi nanowires on as-sputtered films occurs during heat treatment due to the relaxation of stress between the film and substrate, originating from thermal expansion mismatch. The diameter of Bi nanowires was found to decrease with the mean grain size of the film. The grains of Bi film grown at 100 W and annealed having preferred orientation, i.e., (003) and (006), serve as Bi nanowire seeds. The largest MR values of 2246 % at T = 75 K and 286 % at T = 300 K in a 400-nm Bi nanowire were obtained, indicating that high-quality, single-crystalline Bi nanowires could be grown by the proposed stress-induced method. These results provide motivation for exploring the magneto-transport properties of single-crystalline Bi nanowires.