Seeded Topology Optimization for Commercial Foundry Integrated Photonics

Abstract: We present a seeded topology optimization methodology for integrated photonic devices fabricated on foundry platforms that yields improved performance compared to traditional topology optimization. We employ blurring filters and a DRC correction algorithm to more readily meet design rule checks, resulting in devices with fewer artifacts and improved correlation between simulation and measurements. We apply this process to an ultra-compact TE modal multiplexer, a TE mode converter, a polarization rotator, and a high-contrast grating reflector. The measured insertion loss of the TE mode converter was reduced from 1.37 dB to 0.64 dB through this optimization strategy. This approach enables a two-step inverse design process, merging of physics-informed design strategies with inverse design, and ensures strict compliance with foundry constraints throughout optimization.