Abstract To meet the ultra-broadband perfect absorption of visible-infrared light on silicon surfaces, a green, efficient and economical method for fabricating multi-scale micro-nano composite structures in ambient air is proposed. We experimentally demonstrate laser cleaning assisted femtosecond laser ablation for fabricating anti-reflection structures. Laser cleaning technology not only effectively eliminates oxide deposition on the laser textured surfaces, but also manufactures the small scale fine-microstructures and nanostructures. A focused ellipse laser spot is innovatively applied to realize large area and energy decays continuously multiple laser cleaning of laser-treated surfaces, and solve the problem that new oxide deposition is generated in the cleaning process. The processing efficiency is also increased by 4.8 times. The average reflectance of 2.06% is reached from 300 to 2500 nm. Great enhancement of infrared light absorption of silicon from 2.5 to 16 μm is realized experimentally. The average reflectance is reduced to 4.98% with a broadband reflectance below 6.6%. Especially, a reflectance below 5.0% from 2.5 to 10 μm and an average reflectance of 4.3% is achieved, which is the least reported to date by laser processing techniques as far as we know. This strategy for anti-reflection structures is excellent candidate for future optoelectronic devices.

中文翻译：

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用于环境空气中宽带超低反射率硅表面的激光清洗辅助激光烧蚀制备多尺度微纳米结构

摘要 为满足可见光-红外光在硅表面的超宽带完美吸收，提出了一种绿色、高效、经济的环境空气多尺度微纳复合结构制备方法。我们通过实验证明了用于制造抗反射结构的激光清洁辅助飞秒激光烧蚀。激光清洗技术不仅可以有效消除激光纹理表面的氧化物沉积，而且可以制造出小尺度的微细结构和纳米结构。创新应用聚焦椭圆激光光斑，实现大面积、能量连续衰减的激光处理表面多次激光清洗，解决清洗过程中产生新氧化物沉积的问题。处理效率也提高了4.8倍。在 300 至 2500 nm 范围内达到 2.06% 的平均反射率。通过实验实现了硅的红外光吸收从 2.5 到 16 μm 的极大增强。平均反射率降低到 4.98%，宽带反射率低于 6.6%。特别是，在 2.5 至 10 μm 范围内实现了低于 5.0% 的反射率和 4.3% 的平均反射率，这是迄今为止激光加工技术报道最少的。这种抗反射结构的策略是未来光电器件的绝佳候选者。实现了 5 至 10 μm 和 4.3% 的平均反射率，据我们所知，这是迄今为止激光加工技术报道最少的。这种抗反射结构的策略是未来光电器件的绝佳候选者。实现了 5 至 10 μm 和 4.3% 的平均反射率，据我们所知，这是迄今为止激光加工技术报道最少的。这种抗反射结构的策略是未来光电器件的绝佳候选者。