Spontaneous growth of nickel silicide nanowires and formation of self-assembled nanobridges by the metal induced growth method

Nickel monosilicide (NiSi) nanowires (NWs) have been fabricated by the metal induced growth (MIG) method. Ni as a catalyst was deposited on a SiO ₂ coated Si wafer. In a DC magnetron sputtering system, the Ni reacts at 575 °C with sputtered Si to give nanowires. Different metal catalysts (Co and Pd) were used to prove the MIG NW growth mechanism. NiSi NWs were a single crystal structure, 20-80 nm in diameter and 1-10 μm in length. The linear NW growth property provided nanobridge formation in a trenched Si wafer. The trenches in a Si wafer were made by dry etching and a simple, conventional metal lift off method. The self-assembled nanobridge can be applied to form nanocontacts at relatively low temperatures. The MIG NB is a promising 1 dimensional nanoscale building block to satisfy the need of 'self and direct' assembled 'bottom-up' fabrication concepts.