Fan Zhuodong, Yan Kunlun, Zhang Limeng, Qin Jingshuang, Chen Jinbo, Wang Rongping, Shen Xiang
Appl Opt. 2020 Feb 20;59(6):1564-1568. doi: 10.1364/AO.386280.
In this paper, we report the fabrication and characterization of chalcogenide-based planar waveguides for possible applications in broadband light sources and/or biochemical sensing. ${{\rm Ge}{11.5}}{{\rm As}{24}}{{\rm Se}_{64.5}}$GeAsSe film as bottom cladding followed by another layer of ${{\rm As}_2}{{\rm Se}_3}$AsSe was deposited on a thermally oxidized silicon wafer using thermal evaporation, and the waveguides were patterned directly on the ${{\rm As}_2}{{\rm Se}_3}$AsSe layer by UV exposure followed by inductively coupled plasma dry etching. The device structure was optimized by using commercial software (COMSOL Multiphysics) based on complete vector finite components, and the fundamental mode of the waveguide was calculated. By optimizing the geometry of the waveguide, the zero dispersion wavelength was shifted to a short wavelength (at $\sim{2}.{3};\unicode{x00B5} {\rm m}$∼2.3µm), which facilitates supercontinuum generation with shorter wavelength pump source. The insertion loss of the rib waveguides with different widths was measured using the cut-back method, and the best propagation loss at 1550 nm was 1.4 dB/cm.
在本文中，我们报道了基于硫族化物的平面光波导的制备与表征，这些光波导可用于宽带光源和/或生化传感。采用热蒸发法在热氧化硅晶片上沉积${{\rm Ge}{11.5}}{{\rm As}{24}}{{\rm Se}_{64.5}}$（GeAsSe）薄膜作为底部包层，随后再沉积一层${{\rm As}_2}{{\rm Se}_3}$（AsSe），然后通过紫外曝光和电感耦合等离子体干法刻蚀直接在${{\rm As}_2}{{\rm Se}_3}$（AsSe）层上对光波导进行图案化。基于完整的矢量有限元组件，使用商业软件（COMSOL Multiphysics）对器件结构进行了优化，并计算了光波导的基模。通过优化光波导的几何结构，将零色散波长移至短波长（约为2.3微米），这有利于使用较短波长的泵浦源产生超连续谱。使用截断法测量了不同宽度的脊形光波导的插入损耗，在1550纳米处的最佳传播损耗为1.4分贝/厘米。
