Controlled growth of amorphous silicon nanowires via a solid-liquid-solid (SLS) mechanism

Amorphous silicon nanowires (a-SiNW's) with average diameter around 20 nm were synthesized at about 950??C under an Ar/H2 atmosphere on large area of a (111) Si substrate without supplying any gaseous or liquid Si sources. The Si substrate, deposited with a layer of Ni of about 40 nm thick, served itself as a silicon source for the growth of the a-SiNWs. Different from the well-known vapor-liquid-solid (VLS) for conventional whisker growth, it was found that growth of the a-SiNWs was controlled by a solid-liquid-solid mechanism, which is analogous to the VLS model.EI0225-22958