Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 701, Taiwan.
Sci Rep. 2017 Jun 9;7(1):3164. doi: 10.1038/s41598-017-03498-y.
Facile, effective and reliable etching technique for the formation of uniform silicon (Si) nanowire arrays were realized through the incorporation of back substrates with metal-assisted chemical etching (MaCE). In comparison with conventional MaCE process, a dramatic increase of etching rates upon MaCE process could be found by employing the conductive back substrates on p-type Si, while additionally prevented the creation of nanopores from catalytic etching reaction. Examinations on the involving etching kinetics, morphologies, wetting behaviors and surface structures were performed that validated the role of back substrates upon MaCE process. It was found that the involved two pathways for the extraction of electrons within Si favored the localized oxidation of Si at Si/Ag interfaces, thereby increasing the etching rate of MaCE process. This back-substrate involved MaCE could potentially meet the practical needs for the high-yield formation of Si nanowire arrays.
通过在金属辅助化学蚀刻（MaCE）中加入具有金属辅助化学蚀刻（MaCE）的背衬基底，实现了均匀硅（Si）纳米线阵列的简单、有效和可靠的蚀刻技术。与传统的 MaCE 工艺相比，通过在 p 型 Si 上使用导电背衬基底，可以在 MaCE 工艺中发现蚀刻速率的显著提高，同时还可以防止催化蚀刻反应产生纳米孔。对涉及的蚀刻动力学、形态、润湿行为和表面结构进行了研究，验证了背衬基底在 MaCE 工艺中的作用。结果发现，Si 中电子的两种提取途径有利于 Si/Ag 界面处 Si 的局部氧化，从而提高了 MaCE 工艺的蚀刻速率。这种背衬基底参与的 MaCE 有可能满足高产率形成 Si 纳米线阵列的实际需求。
