Si纳米线的固-液-固可控生长及其形成机理分析

Controlled growth of silicon nanowires by solid-liquid-solid method and their formation mechanism

以Au膜作为金属催化剂,直接从n-(111)Si单晶衬底上制备了直径为30—60nm和长度从几微米到几十微米的高质量Si纳米线.实验研究了Au膜层厚、退火温度、N2气流量和生长时间对Si纳米线形成的影响.结果表明,通过合理选择和优化组合上述各种工艺条件,可以实现直径、长度、形状和取向可控的纳米线生长.基于固-液-固生长机理,定性阐述了Si纳米线的形成过程.

High quality silicon nanowires （SiNWs） were grown directly from n-（111） silicon single crystal substrate by using Au film as a metallic catalyst. The diameter and length of the formed nanowires are 30—60 nm and from several micrometers to sereral tens of micrometers, respectively. The effects of Au film thickness, annealing temperature, growth time and N2 gas flow rate on the formation of the nanowires were experimentally investigated. The results confirmed that the silicon nanowires with controlled diameter, length, shape and orientation can be obtained via reasonably choosing and optimizing various technical conditions. The formation process of the silicon nanowires is analyzed qualitatively based on solid-liquid-solid growth mechanism.