Two-axis MEMS positioner for waveguide alignment in silicon nitride photonic integrated circuits

Area of Science:

• Photonics
• Microelectromechanical Systems (MEMS)

Background:

• Efficient integration of photonic integrated circuits (PICs) relies heavily on precise alignment.
• Microelectromechanical systems (MEMS) actuators offer a promising solution for achieving this critical alignment.

Purpose of the Study:

• To develop and demonstrate MEMS positioning actuators for aligning silicon nitride (SiN) waveguides.
• To enable alignment of SiN waveguides within a chip or to active optical components like lasers and amplifiers.

Main Methods:

• Designed and implemented MEMS actuators for precise waveguide positioning.
• Utilized suspended SiN waveguides on a silicon-on-insulator wafer for horizontal displacement.
• Demonstrated light coupling by closing an initial gap between suspended and fixed waveguides.

Main Results:

• Achieved lateral displacement of suspended SiN waveguides by over ±2 µm.
• Obtained an average insertion loss of -1.6 ± 0.06 dB when waveguides were aligned and the gap closed.
• Reported a maximum average loss of approximately -19.00 ± 0.62 dB with a ±2 µm lateral displacement when closing the gap.

Conclusions:

• The developed MEMS positioning actuators are effective for aligning SiN waveguides.
• This technology facilitates efficient light coupling in PICs and has potential for active chip alignment.
• The actuators could also be applied to optical switching functionalities.