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arXiv · 2301.01689

Process Variation-Aware Compact Model of Strip Waveguides for Photonic Circuit Simulation

Aneek James·Anthony Rizzo·Yuyang Wang·Asher Novick·Songli Wang·Robert Parsons·Kaylx Jang·Maarten Hattink·Keren Bergman
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Abstract

We report a novel process variation-aware compact model of strip waveguides that is suitable for circuit-level simulation of waveguide-based process design kit (PDK) elements. The model is shown to describe both loss and -- using a novel expression for the thermo-optic effect in high index contrast materials -- the thermo-optic behavior of strip waveguides. A novel group extraction method enables modeling the effective index's ($n_{\mathrm{eff}}$) sensitivity to local process variations without the presumption of variation source. Use of Euler-bend Mach-Zehnder interferometers (MZIs) fabricated in a 300~mm wafer run allow model parameter extraction at widths up to 2.5~$\mu$m (highly multi-mode) with strong suppression of higher-order mode excitation. Experimental results prove the reported model can self-consistently describe waveguide phase, loss, and thermo-optic behavior across all measured devices over an unprecedented range of optical bandwidth, waveguide widths, and temperatures.

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Aneek James, Anthony Rizzo, Yuyang Wang, Asher Novick, Songli Wang, Robert Parsons, Kaylx Jang, Maarten Hattink, Keren Bergman. 2023-01-04. Process Variation-Aware Compact Model of Strip Waveguides for Photonic Circuit Simulation. https://doi.org/10.1109/jlt.2023.3238847

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