Silicon photonics is the leading platform for pho-tonic integrated circuits (PICs) because of its low fabrication cost and a small area on-chip, which allows the forefront of the industry to develop low-energy consuming devices. For the implementation of PICs, among passive devices, the most used because of its functionality is the power splitter. Y-junctions are power splitters that are compact and can deliver relatively wide-band frequency responses. In order to respond to the current demands of silicon photonics foundries, this work proposes a method based on the Particle Swarm Optimization to design always-feasible and mass-production oriented Y-junctions. We have achieved transmittances above 49%, and a flat frequency response in the SCL optical communications band. © 2020 IEEE.