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arXiv · 1904.03055

Q factor limitation at short wavelength (around 300 nm) in III-nitride-on-silicon photonic crystal cavities

Farsane Tabataba-Vakili·Iannis Roland·Thi-Mo Tran·Xavier Checoury·Moustafa El Kurdi·Sébastien Sauvage·Christelle Brimont·Thierry Guillet·Stéphanie Rennesson·Jean-Yves Duboz·Fabrice Semond·Bruno Gayral·Philippe Boucaud
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Abstract

III-nitride-on-silicon L3 photonic crystal cavities with resonances down to 315 nm and quality factors (Q) up to 1085 at 337 nm have been demonstrated. The reduction of the quality factor with decreasing wavelength is investigated. Besides the quantum well absorption below 340 nm, a noteworthy contribution is attributed to the residual absorption present in thin AlN layers grown on silicon, as measured by spectroscopic ellipsometry. This residual absorption ultimately limits the Q factor to around 2000 at 300 nm when no active layer is present.

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Farsane Tabataba-Vakili, Iannis Roland, Thi-Mo Tran, Xavier Checoury, Moustafa El Kurdi, Sébastien Sauvage, Christelle Brimont, Thierry Guillet, Stéphanie Rennesson, Jean-Yves Duboz, Fabrice Semond, Bruno Gayral, Philippe Boucaud. 2019-04-05. Q factor limitation at short wavelength (around 300 nm) in III-nitride-on-silicon photonic crystal cavities. https://doi.org/10.1063/1.4997124

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