Integrated sensors based on guided optical devices can efficiently and selectively detect molecules in the mid-infrared (mid-IR) spectral range, exploiting the vibrational and rotational modes of these molecules at these wavelengths. In this work, a ridge waveguide based on porous silicon (PSi) layers was developed by electrochemical etching followed by a photolithographic process. The ridge waveguide is capable of propagating light in the mid-IR range (3.90–4.35 µm) with optical losses of approximately 10 dB/cm. An oxidation study was performed to stabilize the porous structure and identify the optimal oxidation degree, that allow mid-IR light to propagate in a ridge waveguide based on PSi material for sensing application. The results showed that the ridge waveguide remains capable of propagating light after undergoing partial oxidation at 300 °C and 600 °C (15% and 36% of the oxidation degree respectively) with optical losses of around 30 dB/cm and 60 dB/cm at the wavelength of 4.1 µm, respectively.

中文翻译：

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中红外波长氧化对多孔硅层集成波导光学性能的影响

基于引导光学设备的集成传感器可以利用这些分子在这些波长下的振动和旋转模式，有效地、选择性地检测中红外 (mid-IR) 光谱范围内的分子。在这项工作中，通过电化学蚀刻和光刻工艺开发了基于多孔硅（PSi）层的脊形波导。脊形波导能够传播中红外范围 (3.90–4.35 µm) 的光，光学损耗约为 10 dB/cm。进行了氧化研究，以稳定多孔结构并确定最佳氧化程度，从而允许中红外光在基于 PSi 材料的脊形波导中传播，用于传感应用。结果表明，脊形波导在300℃和600℃（氧化程度分别为15％和36％）下经历部分氧化后仍然能够传播光，光学损耗分别约为30dB/cm和60dB/cm波长分别为 4.1 µm。