Electronic Photonic Design Automation

Electronic Photonic Design Automation (EPDA) is a class of software tools used to automate the design, layout, simulation, and verification of photonic integrated circuits (PICs), often in conjunction with electronic circuits on the same substrate. EPDA tools enable scalable and manufacturable photonic-electronic systems for applications ranging from data communications to quantum computing.

Motivation and overview

Photonic circuits manipulate light instead of electrical signals, introducing fundamentally different design requirements. Unlike electronic circuits, photonic components are sensitive to wavelength, phase, and geometry, and are often implemented as waveguides, resonators, and other optical structures. This makes the design process more complex, requiring specialized tools beyond those used in traditional EDA.

EPDA tools extend EDA workflows to support photonic-specific constraints and behaviors, enabling full-system design flows that include both photonics and electronics. They are used by chip designers, researchers, and foundries to build and verify integrated photonic systems.

Historical background

In early photonics research, circuit design was mostly manual. Layouts were often drawn by hand, with limited simulation or verification tools. The rise of silicon photonics in the 2000s triggered demand for scalable design automation, leading to the adaptation of EDA principles to photonic domains. Several commercial and academic tools emerged, and standardization efforts began to support interoperability across the design ecosystem.

EPDA design flow

EPDA environments typically provide toolchains analogous to those used in electronic IC design. The following components form the backbone of a typical photonic design flow:

Schematic capture and simulation

Photonic circuits are typically modeled and simulated in the frequency or time domain using tools like Luceda Caphe and Lumerical INTERCONNECT. These tools allow designers to validate circuit behavior before layout.

Layout and physical design

Physical design of PICs involves the placement of waveguides and components using photonic-aware layout tools. Examples include IPKISS and KLayout with SiEPIC plugins. These tools support design-rule-compliant layouts in foundry-compatible formats like GDSII.

Verification

Verification includes:

• Design Rule Checking (DRC): Ensures waveguide spacing, bend radius, and other geometry-based rules are met.
• Layout versus Schematic (LVS): Validates that the physical layout matches the intended schematic structure.
• Parameter extraction: May include optical loss, effective index, or group delay.

Process design kits (PDKs)

EPDA workflows depend on foundry-provided PDKs that define validated building blocks like modulators, detectors, and splitters. PDKs also contain process-specific data such as layer stacks, optical models, and layout templates.

Co-design with electronics

PICs often integrate with electronic drivers, amplifiers, and controllers. Co-design features in EPDA include:

• Floorplanning for combined photonic-electronic chips
• Mixed-signal simulation (e.g., Verilog-A + photonic models)
• Export of netlists into SPICE or hardware description environments

Standardization and interoperability

To ensure compatibility between tools and streamline the design-to-fabrication process, standardization is increasingly important.

Role of foundries and PDKs

Foundries play a key role by releasing standardized PDKs for specific process technologies. These PDKs define layout cells, simulation models, and performance specifications, enabling third-party tools to function reliably across the ecosystem.

openEPDA initiative

openEPDA™ is a public collection of open standards for EPDA, developed by TU/e and the Photonic Integration Technology Center (PITC). It defines:

• Data formats for schematic and layout interchange
• Analytic expression formats for component behavior
• PDK building blocks (uPDK)
• Layout and measurement data formats (CDF, MDF)

The openEPDA initiative also provides a Python-based reference toolkit (openepda) that validates and parses these formats, supporting improved tool interoperability and design reproducibility.

Applications

EPDA tools are used in the development of photonic systems such as:

• Optical transceivers for cloud computing and telecommunications
• Quantum photonic circuits
• On-chip biosensors and lab-on-chip devices
• Photonic neural networks and AI accelerators
• LIDAR systems for autonomous vehicles

Challenges and future directions

EPDA continues to evolve to meet increasing demands. Current challenges include:

• Lack of fully standardized data models across vendors
• Scalability for large, hierarchical photonic circuits
• Accurate modeling of 3D and nonlinear effects
• Seamless integration with electronic IC design flows

Emerging trends include the use of high-level photonic description languages, AI-assisted optimization, and tighter coupling between simulation and manufacturing feedback.

See also

• Electronic design automation
• System on a chip

External links

• Luceda Photonics
• Synopsys Photonic Design
• SiEPIC Tools on GitHub
• openEPDA initiative