In silicon photonics, silicon microdisk resonators with movable waveguides driven by electrostatic comb-drive actuators have been used as wavelength-selective switches. However, the sidewall roughness of silicon waveguides formed by the etching process is the main cause of optical loss in such devices, which leads to the deterioration of the wavelength selectivity. In this study, we fabricated a silicon microdisk resonator with a movable waveguide and performed a hydrogen annealing treatment as a postprocessing step to remove the sidewall roughness. By using scanning electron microscopy, a reduction in sidewall roughness was confirmed following the hydrogen annealing treatment. Then, the extinction ratio at the through port was evaluated while changing the gap between the microdisk and the movable waveguide. A dip in the extinction ratio was observed at the resonant wavelength while decreasing the gap, which indicated that the fabricated device successfully functioned as a wavelength-selective switch. Due to the hydrogen annealing treatment, the quality factor of the dip increased from 7102 to 37 402. These results show that the hydrogen annealing treatment can be used as a postprocessing step and is helpful for improving the wavelength selectivity of silicon photonic wavelength-selective switches.

中文翻译：

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通过氢退火处理改进具有可移动波导的硅微盘谐振器

在硅光子学中，具有由静电梳状驱动致动器驱动的可移动波导的硅微盘谐振器已被用作波长选择开关。然而，通过蚀刻工艺形成的硅波导的侧壁粗糙度是这种器件中光损失的主要原因，这导致波长选择性的恶化。在这项研究中，我们制造了具有可移动波导的硅微盘谐振器，并进行了氢退火处理作为去除侧壁粗糙度的后处理步骤。通过使用扫描电子显微镜，证实了在氢退火处理之后侧壁粗糙度的降低。然后，在改变微盘和可移动波导之间的间隙的同时，评估了在通孔处的消光比。在共振波长处观察到消光比下降，同时减小了间隙，这表明所制造的器件成功地起到了波长选择开关的作用。由于进行了氢退火处理，浸入的品质因数从7102增加到37402。这些结果表明，氢退火处理可以用作后处理步骤，有助于改善硅光子波长选择开关的波长选择性。 。