Fulton Alison Joy, Ozhukil Kollath Vinayaraj, Karan Kunal, Shi Yujun
Department of Chemistry, University of Calgary Calgary AB T2N 1N4 Canada
Department of Chemical and Petroleum Engineering, University of Calgary Calgary AB T2N 1N4 Canada.
Nanoscale Adv. 2020 Jan 31;2(2):896-905. doi: 10.1039/d0na00043d. eCollection 2020 Feb 18.
This work reports the influence of the substrate in the pulsed laser-induced dewetting (PLiD) of Au thin films for the fabrication of nanoparticle (NP) arrays. Two substrates were studied, , polished silicon and porous silicon (PS), the latter being fabricated electrochemical anodization in HF-containing electrolytes. The effect of both PLiD and substrate preparation parameters was explored systematically. On polished silicon substrates, it has been shown that uniform, randomly arranged NPs between 15 ± 7 nm and 89 ± 19 nm in diameter are produced, depending on initial thin film thickness. On PS however, there are topographical features that lead to the formation of ordered NPs with their diameters being controllable through laser irradiation time. The presence of surface pores and the appearance of surface ripples under low HF concentrations (<9.4 wt%) during electrochemical anodization results in this unique dewetting behaviour. Through AFM analysis, it has been determined that the ordered NPs sit within the valleys of the ripples, and form due to the atomic mobility enabled using the PLiD approach. This work has demonstrated that the utilization of topographically complex PS substrates results in size controllable and ordered NPs, while the use of polished Si does not enable such control over array fabrication.
本文报道了衬底对用于制备纳米颗粒（NP）阵列的金薄膜脉冲激光诱导去湿（PLiD）过程的影响。研究了两种衬底，即抛光硅和多孔硅（PS），后者是通过在含HF的电解质中进行电化学阳极氧化制备的。系统地探讨了PLiD和衬底制备参数的影响。在抛光硅衬底上，已表明根据初始薄膜厚度可产生直径在15±7nm至89±19nm之间的均匀、随机排列的NP。然而，在PS上，存在一些形貌特征，可导致形成有序的NP，其直径可通过激光照射时间控制。电化学阳极氧化过程中在低HF浓度（<9.4 wt%）下表面孔隙的存在和表面波纹的出现导致了这种独特的去湿行为。通过原子力显微镜（AFM）分析确定，有序的NP位于波纹的谷底，并且是由于使用PLiD方法实现的原子迁移而形成的。本文表明，利用形貌复杂的PS衬底可得到尺寸可控且有序的NP，而使用抛光硅则无法对阵列制备进行这种控制。
