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arXiv · 2201.04937

Monolithic integration of 940 nm AlGaAs distributed Bragg reflectors on bulk Ge substrates

Yunlong Zhao·Jia Guo·Markus Feifel·Hao-tien Cheng·Yun-cheng Yang·Liming Wang·Lukas Chrostowski·David Lackner·Chao-hsin Wu·Guangrui·Xia
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Abstract

High quality 940 nm Al$_x$Ga$_{1-x}$As n-type distributed Bragg reflectors (DBRs) were successfully monolithically grown on off-cut Ge (100) substrates. The Ge-DBRs have reflectivity spectra comparable to those grown on conventional bulk GaAs substrates and have smooth morphology, reasonable periodicity and uniformity. These results strongly support VCSEL growth and fabrication on more scalable bulk Ge substrates for large scale production of AlGaAs-based VCSELs.

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Yunlong Zhao, Jia Guo, Markus Feifel, Hao-tien Cheng, Yun-cheng Yang, Liming Wang, Lukas Chrostowski, David Lackner, Chao-hsin Wu, Guangrui, Xia. 2021-12-22. Monolithic integration of 940 nm AlGaAs distributed Bragg reflectors on bulk Ge substrates. https://arxiv.org/abs/2201.04937

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