Controllable Fabrication of Large-Size Defect-Free Domains of 2D Colloidal Crystal Masks Guided by Statistical Experimental Design

Large defect-free domains of a hexagonal packed monolayer silica spheres with the size 4000 µm2 were successfully prepared by dual-speed spin coating. Experimental design and statistical analysis instead traditional ‘changing one separate factor at time’ (COST) approach employed to guide implementation experiments. With its assistance, hexagonal-close-packed (HCP) percentage was elevated 84% in this study. Furthermore, almost all samples parameters selected ranges possessed more than 60% HCP percentage. In addition, optimal values for suspension concentration, first rotation speed, spinning time obtain well-ordered arrays also identified as 30 wt.%, 1000 rpm 20 s, respectively.