Goh Chiatzun, Coakley Kevin M, McGehee Michael D
Department of Materials Science & Engineering, Stanford University, Stanford, California 94305, USA.
Nano Lett. 2005 Aug;5(8):1545-9. doi: 10.1021/nl050704c.
We demonstrate a method for embossing titania sol--gel precursor with poly(methyl methacrylate) (PMMA) molds to make thin films of titania that have dense arrays of 35--65 nm diameter pores, whose features are 1 order of magnitude smaller than those previously demonstrated for sol--gel molding. We show that the high modulus of PMMA is necessary to preserve small features with high aspect ratios on the mold for nanopatterning. The molds are prepared by thermally infiltrating PMMA into anodic alumina templates, whose pore dimensions and depths are adjustable by varying anodization conditions. The difficulties associated with mold release from a master are avoided by wet etching the template. These titania films, and others made with other semiconductors, could be useful for photovoltaic, photocatalytic, and sensing applications where nanostructuring of surfaces with controlled dimensions are essential.
我们展示了一种用聚甲基丙烯酸甲酯（PMMA）模具对二氧化钛溶胶 - 凝胶前驱体进行压花的方法，以制备具有直径为35 - 65nm致密孔阵列的二氧化钛薄膜，其特征尺寸比先前溶胶 - 凝胶成型所展示的小1个数量级。我们表明，PMMA的高模量对于在模具上保留用于纳米图案化的高纵横比小特征是必要的。通过将PMMA热渗透到阳极氧化铝模板中来制备模具，其孔尺寸和深度可通过改变阳极氧化条件来调节。通过对模板进行湿蚀刻避免了与从母模脱模相关的困难。这些二氧化钛薄膜以及用其他半导体制成的薄膜，对于表面具有可控尺寸的纳米结构至关重要的光伏、光催化和传感应用可能是有用的。
