A Review: Methods To Fabricate Vertically Oriented Metal Nanowire Arrays

Nanowires can be described as one-dimensional-like structures: elongated solids with two dimensions thinner than about a micrometer. They allow the study of novel physical phenomena and have many technological applications, including capture and storage of energy, thermal transport, and sensing. These applications often use arrays of nanowires on flat surfaces, and sometimes specifically require the nanowires to be vertically oriented rather than randomly oriented, arranged in lithographically ordered arrays rather than randomly distributed, or both. In addition, the nanowires’ height, diameter, cross-sectional shape, and the array pitch often must be controlled. Methods exist to exercise much of this control over insulating and semiconducting nanowires, but less control has been demonstrated for metal nanowire fabrication. Here, we review methods published for the fabrication of metal nanowires, and highlight areas in need of further development. Microwire fabrication is discussed in the context of methods that show promise for adaptation to nanowires.