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arXiv · 2104.05227

Fabrication of Ultra-High Q Silica Microdisk Using Chemo-Mechanical Polishing

S. Honari·S. Haque·Tao Lu
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Abstract

Here we demonstrate that adding a chemo-mechanical polishing (CMP) procedure to conventional photolithography, a silica microdisk with ultra-high quality factors ($>10^8$) can be fabricated. By comparing with the intrinsic optical quality factor (Q) measured at 970~nm, we observe that due to the significantly reduced surface roughness, at 1550~nm wavelength the water molecule absorption at the cavity surface supersedes Rayleigh scattering as the dominant factor for Q degradation.

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S. Honari, S. Haque, Tao Lu. 2021-04-12. Fabrication of Ultra-High Q Silica Microdisk Using Chemo-Mechanical Polishing. https://doi.org/10.1063/5.0051674

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