Membrane InGaAsP Mach-Zehnder modulator with SiN:D waveguides on Si platform

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Silicon nitride (SiN:D) waveguides offer low loss and CMOS compatibility.
• Integration of III-V materials with silicon photonics is challenging but promising for advanced devices.
• Mach-Zehnder modulators are key components in optical communication systems.

Purpose of the Study:

• To integrate a high-efficiency InGaAsP Mach-Zehnder modulator with SiN:D waveguides on a silicon substrate.
• To achieve high optical confinement and efficient coupling between dissimilar waveguides.
• To demonstrate high-speed, error-free operation of the integrated modulator.

Main Methods:

• Fabrication of hydrogen-free deuterated silicon nitride (SiN:D) waveguides using a low-temperature backend process.
• Integration of an InP-based layer for high optical confinement and coupling.
• Characterization of the Mach-Zehnder modulator's performance, including VπL, insertion loss, and high-speed operation.

Main Results:

• Achieved a high optical confinement factor of approximately 50% with the InP-based layer.
• Demonstrated a low VπL of 0.4 Vcm and an insertion loss of ~4.5 dB for the Mach-Zehnder modulator.
• Confirmed error-free operation at 40-Gbit/s non-return-to-zero data rates.

Conclusions:

• The integrated InGaAsP/SiN:D Mach-Zehnder modulator is a promising solution for high-speed optical communications.
• The low-temperature integration process enables efficient coupling and high modulator performance.
• This work paves the way for advanced silicon photonic integrated circuits.