Chemical routes to two-dimensional photonic crystal sensors equipped with nano/microcavities

配备纳米/微腔的二维光子晶体传感器的化学路线

• 批准号: 426173341
• 负责人: Professorin Dr. Claudia Pacholski
• 金额: --
• 依托单位: Fachbereich II: Mathematik, Physik, Chemie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/426173341?language=en
• 关键词: Chemical; routes; two; dimensional; photonic

The development of simple, small, and highly sensitive sensors for detecting hazardous substances is one of the hot topics in both academic research and commercial applications. In this context, optical sensors based on nano/microstructured silicon are highly interesting and different configurations such as Mach-Zehnder interferometers, gratings, waveguides and photonic crystal devices have been investigated. These sensors can show extraordinary sensing performance if their geometrical lay-out is well designed and specific optical read-out methods are applied. Most promising for achieving extremely high sensitivities are optical sensors based on two-dimensional photonic crystal slabs. The sensors are often realized by creating a periodic array of holes in a thin silicon slab which can exhibit a photonic band gap (stop band) characterized by the prevention of light propagation at a range of frequencies. Thereby, narrow resonance linewidths in their optical spectra are achieved making them ideal candidates for sensor applications. Furthermore, by introducing point or line defects into the periodic lattice of holes optical nano/microcavities are formed facilitating a strong confinement of light. Despite the high demand for these sensors, two-dimensional photonic crystal slabs are almost exclusively fabricated by top-down methods, e.g. photo- and e-beam lithography. These methods allow for a precise definition of the geometric dimensions of nanostructures, including their size and morphology, but require sophisticated equipment. In contrast, bottom-up approaches provide simple and cost-efficient methods for structuring large areas using self-assembly processes. Especially in colloidal lithography tremendous progress was made towards the realization of highly ordered and hierarchical nanostructures. However, until now the fabrication of nanomaterials with site-selective variations in their dimensions on the micro/nanoscale by colloidal lithography was barely investigated even though simple, fast and cost-efficient production methods for these kinds of materials are highly desirable. This project aims at the fabrication of 2D photonic crystal sensors equipped with nano/microcavities using a combination of colloidal lithography and metal-assisted etching of silicon-based substrates. For this purpose, the exceptional properties of stimuli-responsive hydrogel microgels will be exploited in order to provide independent control over lattice constants and colloid diameters in two-dimensional arrays of hydrogel microgels deposited on the substrate surface. Resulting colloidal masks will be used for preparing gold nanodisc arrays which will subsequently be employed for metal-assisted etching of the silicon-based substrate. Thereby, 2D photonic crystal sensors equipped with nano/microcavities will be realized in a simple and cost-efficient way on large areas.

开发简单、小型、高灵敏度的有害物质检测传感器是学术研究和商业应用的热点之一。在这种情况下，基于纳米/微结构硅的光学传感器是非常有趣的，不同的配置，如马赫-曾德尔干涉仪，光栅，波导和光子晶体器件已被研究。这些传感器可以显示非凡的传感性能，如果他们的几何布局设计良好，并应用特定的光学读出方法。最有希望实现极高的灵敏度是基于二维光子晶体板的光学传感器。传感器通常通过在薄硅板中创建孔的周期性阵列来实现，所述薄硅板可以表现出光子带隙（阻带），其特征在于阻止在一定频率范围内的光传播。因此，实现了它们的光谱中的窄共振线宽，使它们成为传感器应用的理想候选者。此外，通过将点或线缺陷引入到孔的周期性晶格中，形成光学纳米/微腔，从而促进光的强限制。尽管对这些传感器的需求很高，但二维光子晶体板几乎完全是通过自上而下的方法制造的，例如照片和电子束光刻。这些方法允许精确定义纳米结构的几何尺寸，包括它们的大小和形态，但需要复杂的设备。相比之下，自下而上的方法提供了简单且具有成本效益的方法，用于使用自组装过程构建大面积。特别是胶体光刻技术在实现高度有序和分级的纳米结构方面取得了巨大的进展。然而，到目前为止，通过胶体光刻法在微米/纳米尺度上制造具有位置选择性尺寸变化的纳米材料几乎没有研究，即使这些种类的材料的简单，快速和具有成本效益的生产方法是非常可取的。该项目旨在利用胶体光刻和硅基衬底的金属辅助蚀刻相结合的方法制造配备有纳米/微腔的二维光子晶体传感器。为此，将利用刺激响应性水凝胶微凝胶的特殊性质，以提供对沉积在基底表面上的水凝胶微凝胶的二维阵列中的晶格常数和胶体直径的独立控制。所得胶体掩模将用于制备金纳米盘阵列，其随后将用于硅基衬底的金属辅助蚀刻。因此，配备有纳米/微腔的2D光子晶体传感器将以简单且具有成本效益的方式在大面积上实现。