Design and Optimization of High-Performance Multi-Channel Wavelength Division Multiplexing (WDM) Devices on Silicon-Based Platforms

1.    Project Objective

The primary objective of this research project is to design, simulate, and optimize a set of high‑performance multi‑channel Wavelength Division Multiplexing (WDM) devices. The work focuses on comparing three architectures—Arrayed Waveguide Gratings (AWG), Cascaded Mach–Zehnder Interferometers (MZI), and Micro‑Ring Resonator (MRR) based filters—implemented on Silicon Nitride (SiN) photonic platforms. The goal is to achieve low crosstalk, low insertion loss, and high spectral efficiency.

2.    Scope of Work

The project includes the architectural design and optimization of an 8‑ or 16‑channel WDM system using:

• AWG: Phased‑array waveguides enabling dense wavelength multiplexing.
• Cascaded MZI: Lattice‑filter structures providing flat‑top passbands.
• MRR: High‑Q resonators offering compact, wavelength‑selective filtering.

The WDM devices will be designed for SiN platform and target different wavelengths in visible band, near‑infrared, O‑band, and C‑band.

3.    Methodology

The design cycle includes:

• Component‑level design: Waveguide geometries, couplers, and resonators will be optimized for single‑mode operation and low loss using 2D/3D Finite‑Difference Time‑Domain (FDTD) and Eigenmode Expansion (EME) solvers.
• Circuit‑level simulation: The spectral response of AWG, MZI, and MRR‑based WDM devices will be modelled and compared.
• Tolerance analysis: Fabrication variations (e.g., waveguide width deviations, etch depth errors) will be introduced to evaluate robustness and performance stability.
• Test structure definition: Dedicated test structures and design‑of‑experiment (DoE) patterns will be defined to support future fabrication and characterization.
• Layout and GDS generation: The selected designs will be translated into full mask layouts and exported as GDS files for foundry submission.

Designs will be optimized to:

• Minimize insertion loss (IL)
• Reduce inter‑channel crosstalk
• Maximize free spectral range (FSR)
• Improve channel uniformity
• Reduce sensitivity to fabrication variations and process imperfections

4.    Expected Outcomes

The project will deliver a comprehensive design library of WDM components and a detailed comparative analysis of the three architectures. The final report will identify the most robust and fabrication‑tolerant design for next‑generation optical interconnects. The selected design will be laid out for fabrication on the imec silicon photonics platform.

Master's Degree: Master of Engineering Science, Master of Science

Required educational background: Computer Science, Electromechanical Engineering, Electrotechnics/Electrical Engineering, Nanoscience & Nanotechnology

Duration: 1 year

University Promotor: Xavier Rottenberg (KU Leuven)

For more information or application, please contact the supervising scientists Jeonghwan Song (jeonghwan.song@imec.be) and Zeinab Jafari (zeinab.jafari@imec.be).

Only for self-supporting students.