Stitching-loss-tolerant silicon nitride waveguides on glass for panel-level optical interconnects

In this Letter, we propose a stitching-loss-tolerant silicon nitride (SiN) waveguide structure that alleviates optical loss caused by reticle stitching, which inevitably arises in i-line stepper lithography suitable for low-cost, large-area fabrication. At a wavelength of 1310 nm, the measured stitching loss of straight waveguides is 0.105 dB/interface. In contrast, tapered waveguides with stitching widths (W_s) of 2 µm and 3.5 µm demonstrate significantly reduced losses of 0.0678 and 0.0213 dB/interface. These results pave the way for glass-based panel-level optical interconnect enabled by cost-effective fabrication, addressing a critical bottleneck in next-generation optical packaging.