Preparation of patterned boron nanowire films with different widths of unit-cell and their field emission properties**Project supported by the National Basic Research Program of China (Grant Nos. 2013CB933604), the National Natural Science Foundation of China (Grant No. 51572290), and the Fund from the Chinese Academy of Sciences (Grant Nos. 1731300500015 and XDB07030100).

Abstract

Large-area patterned films of boron nanowires (BNWs) are fabricated at various densities by chemical vapor deposition (CVD). Different widths of unit-cell of Mo masks are used as templates. The widths of unit-cell of Mo masks are 100 μm, 150 μm, and 200 μm, respectively. The distance between unit cells is 50 μm. The BNWs have an average diameter of about 20 nm and lengths of 10 μm–20 μm. High-resolution transmission electron microscopy analysis shows that each nanowire has a β-tetragonal structure with good crystallization. Field emission measurements of the BNW films show that their turn-on electric fields decrease with width of unit-cell increasing.