Metallic Nanowires Grown via Field-Emission Induced Growth as Electron Sources

Single metallic nanowires can be grown from a cold field emission tip in the presence of a precursor, such as an organometallic compound. Electron emission from the newly grown nanowire tip continues the growth and can yield nanowires with lengths ranging from tens of nm to even hundreds of microns depending on the growth time. This approach of Field-Emission-Induced Growth (FEIG) has been used for various applications, including nanowire interconnects, scanning-probe tips, and in particular, as field-emission sources. This paper briefly describes the growth methodology and mechanism, and the characteristics of the material thus derived. Ultrathin tungsten nanowires of 5 nm in diameter and several hundred nm length have been characterized for their potential as a field emitter. After flashing, cold-field-emission current stability with standard deviation of better than 1% has been observed at vacuum levels of similar to 10(-9) mbar. The properties of such field emitters, and the reasons underlying the performance are discussed.