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arXiv · 2106.09476

Efficient and compact thermo-optic phase shifter in silicon-rich silicon nitride

Hani Nejadriahi·Steve Pappert·Yeshaiahu Fainman·Paul Yu
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Abstract

The design, fabrication, and characterization of low loss ultra-compact bends in high index (n = 3.1 at {\lambda} = 1550 nm) PECVD silicon rich silicon nitride (SRN) is demonstrated and utilized to realize efficient, small footprint thermo-optic phase shifter. Compact bends are structured into a folded waveguide geometry to form a rectangular spiral within an area of 65 x 65 \mum2 possessing a total active waveguide length of 1.2 mm. The device features a phase shifting efficiency of 8 mW/{\pi} and a 3 dB switching bandwidth of 15 KHz. We propose SRN as a promising thermo-optic platform combining the properties of silicon and silicon stoichiometric nitride

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Hani Nejadriahi, Steve Pappert, Yeshaiahu Fainman, Paul Yu. 2021-06-14. Efficient and compact thermo-optic phase shifter in silicon-rich silicon nitride. https://doi.org/10.1364/ol.431757

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