Preparation of NiSi₂Nanowires with Low Resistivity by Reaction Between Ni Coating and Silicon Nanowires

Abstract

Nickel silicide nanowires are promising interconnection and gate materials for one dimensional nanoelectronic devices. In this report, NiSi 2 nanowires with low resistivity of 23.5 cm were prepared by nickel sputtering on silicon nanowires and 550 C annealing. High resolution transmission microscopy, selective area electron diffraction and energy dispersive X-ray spectroscopy were used to characterize the structure and composition of NiSi 2 nanowires. Four-terminal electrical measurement was used to verify the electrical property of nanowires. A low energy implantation mechanism is introduced to explain the formation of silicon rich nickel silicide.

Phase-controlled synthesis of nickel silicide nanostructures

“…Recently, various strategies have been developed for the growth of nickel silicide nanostructures involving about six stable nickel silicide phases, such as Ni 3 Si NWs [14], Ni 31 Si 12 NWs [15], Ni 2 Si NWs [11,16], Ni 3 Si 2 NWs [17], NiSi NWs [9,12,13], and NiSi 2 NWs [18], some of which have been successfully applied to nanoscale devices [19,20]. Generally, the method to synthesize different phases and morphologies of nickel silicides can be divided into two routes: delivery of Ni precursors to silicon and deposition of silicon sources on Ni film, both of which are based on the fundamental and crucial process of Ni-diffusion in silicon [9,12,13,21,22].…”

Nanostructural Transformation and Formation of Heterojunctions from Si Nanowires

“…This finding also indicated a method for fabricating high quality NiSi 2 nanowires or NiSi 2 /Si nanowire junctions. Since the reaction temperature for the Si nanowires with thick oxide shells is high, the growth rate of NiSi 2 is much faster than that of the Ni silicide fabricated by the point-contact reaction (0.11 nm/s) as reported by Lu et al 5 In previous studies, 17,18 several methods for converting Si nanowires to NiSi 2 nanowires have been reported. Using arc ion implantation in vacuum, we have synthesized NiSi 2 /Si structure on Si nanowire surfaces.…”

“…However, it was difficult to improve the quality of these silicide nanowires by further annealing at a higher temperature because a too high annealing temperature caused change of the nanowire morphology. Zeng et al 17 reported a sputtering method to coat Si nanowires using the Ni ions with a relative low kinetic energy (about 18 eV). 19 They sug-gested that because of the damaging or implantation effect some Ni ions could be implanted into the nanowire surface region.…”

“…In previous studies, , several methods for converting Si nanowires to NiSi 2 nanowires have been reported. Using arc ion implantation in vacuum, we have synthesized NiSi 2 /Si structure on Si nanowire surfaces.…”

Spatially Sequential Growth of Various WSi2 Networked Nanostructures and Mechanisms

“…9−12 Research on these materials is driven by their distinguished properties, such as high electrical conductivity 1,3,4,13 and superior thermal 14 and chemical stability. 14−16 Metallic silicides including TiSi 2 , 3,11 MnSi, 17 and NiSi 6,7,18 have been used as interconnects in electronic devices due to their low contact resistance. In addition, these materials are potential candidates for high-temperature applications as they usually have high melting points and show good oxidation resistance.…”