ZeroPDK: A Python-Based Software Platform for Programmable Layout and Design Automation of Photonic Integrated Circuits

Background

The field of photonic integrated circuit (PIC) design has grown rapidly in recent years, driven by the increasing demand for high-speed data transmission, advanced sensing, and emerging quantum technologies. Unlike traditional electronic circuits, photonic chips manipulate light to perform complex functions, requiring precise control over waveguide geometries, device placement, and fabrication constraints. As photonic systems scale in complexity, designers must manage a growing number of components and intricate layouts, making manual design approaches impractical and error-prone. To address these challenges, specialized software tools have been developed to automate and streamline the PIC design process, aiming to reduce development time, minimize errors, and facilitate the transition from design to fabrication.

Despite these advancements, current photonic design tools face significant limitations. Many existing solutions are built on proprietary platforms or rely on rigid, non-programmable workflows, restricting their adaptability to new technologies and custom design requirements. Furthermore, these tools often lack robust support for process design kits (PDKs), which are essential for ensuring manufacturability and compatibility with foundry processes. The absence of open, extensible frameworks also limits integration with modern programming languages and open-source libraries, hindering innovation and collaboration within the photonics community. As a result, designers frequently encounter bottlenecks in automating complex layouts, managing technology-specific constraints, and efficiently iterating on large-scale photonic chip designs.

Technology

ZeroPDK is a Python-based software platform engineered to streamline and enhance the design and layout of large-scale photonic integrated circuits. By interfacing directly with the Klayout layout editor, ZeroPDK offers advanced features such as programmable cell management, comprehensive technology management, and photonic-specific geometric algorithms. Central to its functionality is a process design kit (PDK) factory, which supports both client-side and foundry-side workflows, enabling the scripted and automated creation of complex photonic chip layouts. The tool’s Python foundation allows users to tap into a vast ecosystem of open-source libraries, making it highly extensible and adaptable to a wide range of photonic design requirements. While currently dependent on Klayout for layout editing, ZeroPDK’s architecture is designed for potential standalone operation in the future.

What differentiates ZeroPDK is its unique integration of Python’s versatility with the specialized needs of photonic chip design. Unlike traditional photonic layout tools, which may be limited by proprietary scripting languages or closed ecosystems, ZeroPDK leverages Python’s widespread adoption and robust library support to provide a more flexible and programmable environment. This not only accelerates the design process through automation and scripting but also enables rapid prototyping and customization for both academic and industrial users. The tool’s effectiveness has been demonstrated through successful fabrication and internal verification of layouts by researchers, and its commercial potential is underscored by interest from industry stakeholders. By uniting intuitive layout management with domain-specific algorithms in an open, extensible framework, ZeroPDK sets itself apart as a next-generation solution for photonic chip design and manufacturing.

Benefits

• Enables scripted layout of large-scale photonic integrated circuits, improving design efficiency
• Provides programmable cell and technology management tailored for photonic chip design
• Incorporates photonic-specific geometric algorithms to enhance layout accuracy and functionality
• Includes a process design kit (PDK) factory usable by both clients and foundries, supporting manufacturing workflows
• Built on Python, allowing integration with a wide range of open-source libraries for extended capabilities
• Validated through practical use and fabrication, demonstrating reliability and practical applicability
• Designed with flexible architecture that could potentially operate independently of the Klayout tool

Applications

• Automated photonic chip layout design
• Custom process design kit creation
• Foundry-compatible photonic circuit scripting
• Rapid prototyping of photonic devices
• Integration with open-source Python tools

Additional info

ZeroPDK is a Python-based software tool for large-scale photonic chip design. It interfaces with Klayout, providing programmable cell/technology management, photonic-specific geometric algorithms, and a Process Design Kit (PDK) factory. Leveraging open-source libraries, this system enables scripted layout of complex photonic integrated circuits for both clients and foundries.