The TLX-VIS Component Library for the AIM Photonics Silicon Nitride Passive PIC Process

Silicon-nitride-based photonic integrated circuits (PICs) can operate with low loss at visible and near-infrared wavelengths. This spectral range is essential for many applications in chemical and biological sensing, quantum sensing and networking, physical sensing, precision timekeeping, and augmented/virtual reality. At present, high-quality silicon nitride PIC platforms optimized for operation in the visible are offered by low-volume custom foundries or by 200 mm silicon-based foundries. Both typically lack the minimum feature sizes and wafer throughput required for high-yield, high-volume operation at short wavelengths. In this work we describe a new component library and foundry process developed at AIM Photonics, a state-of-the-art PIC foundry. The TLX-VIS component library for the Silicon Nitride Passive PIC process is designed to operate in three bands at wavelengths from 500 nm to 1000 nm. A trench down to the primary waveguide layer is offered for sensing applications, and a dicing trench enables access to waveguide facets for low loss edge coupling. Propagation losses range from 0.2 dB/cm at 785 nm to 2 dB/cm at 532 nm. The component library is designed for both the TE₀₀ and TM₀₀ modes and includes broadband directional couplers, polarization rotators, edge and grating couplers, lattice filters, and high-Q ring resonators. The waveguides have small minimum bend radii (<100 µm) and low fluorescence, which is critical for applications in Raman sensing and quantum information. The component library and PICs are compatible with AIM Photonics' Test, Assembly, and Packaging facility, enabling fully-packaged, fiber-attached assemblies.