Department of Applied Chemistry, Kyung Hee University, Yongin, Gyeonggi 17104, Republic of Korea.
Nanotechnology. 2019 Oct 4;30(40):405202. doi: 10.1088/1361-6528/ab2d05. Epub 2019 Jun 26.
Silicon photonic structures have attracted a great deal of attention due to their potential benefits of efficient light management in optoelectronic applications. In this paper, we demonstrate broadband optical absorption enhancement in solution-processed amorphous silicon (a-Si) by leveraging the advantages of silicon photonic structures. Graded refractive index silicon multi-layer structures are employed by modulating optical constants with simple process optimization, resulting in significantly improved reflectance over a broad range of visible wavelengths. In addition, nanopatterning flexibility of solution-processed silicon provides benefits for tailoring silicon optical properties. With the incorporation of the two-dimensional submicron pattern into silicon films, the absorptivity of silicon films improves considerably below the wavelength of the bandgap (λ ∼ 800 nm), and the limited bandwidth of absorptivity in silicon films can be extended to near-infrared wavelengths by coating with a thin gold layer. The methodology is generally applicable to a platform for improving the broadband optical absorption of photonic and optoelectronic devices.
硅光子结构因其在光电应用中高效光管理的潜在优势而受到广泛关注。在本文中，我们通过利用硅光子结构的优势，展示了溶液处理非晶硅（a-Si）的宽带光吸收增强。通过简单的工艺优化来调制光学常数，使用梯度折射率硅多层结构实现了在宽可见光波长范围内的显著改善反射率。此外，溶液处理硅的纳米图案化灵活性为调整硅光学性质提供了优势。通过将二维亚微米图案融入硅膜中，硅膜在带隙波长（λ∼800nm）以下的光吸收率显著提高，并且通过涂覆薄金层，硅膜的光吸收率的有限带宽可以扩展到近红外波长。该方法通常适用于提高光子和光电设备宽带光吸收的平台。
