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arXiv · 2608.09003

Wafer-scale monolithic integration of Ce:YIG films and magneto-optical isolators on silicon

Tianchi Zhang·Yucong Yang·Weihao Yang·JieJun Su·Tianyi Ma·Xuan Zhao·Junxian Wang·Di Wu·Zhenyuan Ren·Yi Shuai·Zixuan Wei·Lei Bi
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Abstract

Silicon integrated cerium doped yttrium iron garnet (Ce:YIG) thin films are promising candidates for integrated nonreciprocal photonic devices, cryogenic photonic modulators and optical computing applications. However, previously reported Ce:YIG thin film on silicon is limited to milimeter sizes. Wafer-scale integration and non-destructive characterization of high quality Ce:YIG thin films on silicon has been elusive. Here, we report growth of 4-inch wafer-scale Ce:YIG thin films on silicon substrates by radio-frequency magnetron sputtering. Strong Faraday effect of 2318 deg/cm, low propagation loss of 80 dB/cm and excellent thickness uniformity of 3.5% is demonstrated across the 4-inch silicon wafer. Furthermore, a custom designed wafer-scale, non-destructive magneto-ellipsometry was established to characterize the film thickness, optical constants and magneto-optical constants across the wafer. Wafer-scale integration of ring resonator type magneto-optical isolators are also demonstrated. Our work demonstrates a step forward toward wafer-scale heterogeneous integration and characterization of magneto-optical thin films on silicon, providing material candidates for non-reciprocal photonic device arrays, magneto-optical in-memory computing networks and integrated magneto-optic magnetometers.

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Tianchi Zhang, Yucong Yang, Weihao Yang, JieJun Su, Tianyi Ma, Xuan Zhao, Junxian Wang, Di Wu, Zhenyuan Ren, Yi Shuai, Zixuan Wei, Lei Bi. 2026-08-10. Wafer-scale monolithic integration of Ce:YIG films and magneto-optical isolators on silicon. https://arxiv.org/abs/2608.09003

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