Millimeter-Long and Uniform Silicon Nanocables

Abstract

An ultralong Si nanocable has been prepared by simple thermal evaporation of SiO powder mixed with a small amount of Sn. The nanocable has a uniform diameter of about 680 nm and millimeters in length. The core of the nanocable is single-crystal Si with an average diameter of 160 nm, and the shell is composed of compact amorphous SiO x with a uniform thickness of 260 nm. The cladding SiO x emits strong light in a wide spectral range from UV to visible. In particular, each nanocable has a droplet head of Si-Sn eutectic and an uncovered Si core at the tail. The nanocables can be directly fabricated into metal-oxide-semiconductor field effect transistors (MOSFETs) via simple thermal deposition of Au electrodes. The performance of the MOSFETs reveals that the Si nanocables are p-type semiconductors with 1.1 x 10 17 cm -3 hole concentration and 3.69 cm 2 V -1 s -1 hole mobility.