A Compact and Low-Loss MMI Coupler Fabricated With CMOS Technology

• Main Authors: Zhen Sheng, Zhiqi Wang, Chao Qiu, Le Li, Albert Pang, Aimin Wu, Xi Wang, Shichang Zou, Fuwan Gan
• Format: Article
• Language: English
• Published: IEEE 2012-01-01
• Series: IEEE Photonics Journal
• Subjects: Multimode interference (MMI) coupler; low loss; silicon photonics
• Online Access: https://ieeexplore.ieee.org/document/6363508/
• ISSN: 1943-0655

We present the design, fabrication, and measurement of a compact and low-loss multimode interference (MMI) coupler based on the silicon nanowire waveguide. The device is carefully designed to achieve both a good performance and a compact size by using the mode matching method. The device is fabricated on silicon-on-insulator (SOI) with 0.13-μm CMOS technology. By measuring the MMI coupler with a cascaded configuration, a very low excess loss of 0.06 dB at the wavelength of 1550 nm is obtained. The device can also work well for a wide wavelength band. The present MMI coupler is very compact with a footprint of ~ 3.6 × 11.5 μm² for the multimode region.