Shen Mengyan, Carey James E, Crouch Catherine H, Kandyla Maria, Stone Howard A, Mazur Eric
Department of Physics and School of Engineering and Applied Sciences, Harvard University, 9 Oxford Street, Cambridge, Massachusetts 02138, USA.
Nano Lett. 2008 Jul;8(7):2087-91. doi: 10.1021/nl080291q. Epub 2008 Jun 10.
We report on the formation of high-density regular arrays of nanometer-scale rods using femtosecond laser irradiation of a silicon surface immersed in water. The resulting surface exhibits both micrometer-scale and nanometer-scale structures. The micrometer-scale structure consists of spikes of 5-10 mum width, which are entirely covered by nanometer-scale rods that are roughly 50 nm wide and normal to the surface of the micrometer-scale spikes. The formation of the nanometer-scale rods involves several processes: refraction of laser light in highly excited silicon, interference of scattered and refracted light, rapid cooling in water, roughness-enhanced optical absorptance, and capillary instabilities.
我们报道了通过对浸没在水中的硅表面进行飞秒激光辐照，形成高密度规则排列的纳米级棒状结构。所得表面呈现出微米级和纳米级结构。微米级结构由宽度为5 - 10微米的尖峰组成，这些尖峰完全被纳米级棒状结构覆盖，纳米级棒状结构宽度约为50纳米，且垂直于微米级尖峰的表面。纳米级棒状结构的形成涉及多个过程：激光在高度激发的硅中的折射、散射光和折射光的干涉、在水中的快速冷却、粗糙度增强的光吸收以及毛细管不稳定性。
