Why we are using blockage Layers in Analog Layout?

When we work on analog layout design, especially at advanced technology nodes, we know how important layout precision, matching, and routing control are. That’s where blockage layers come in—they play a crucial role in helping us restrict auto-router tools or even our own manual routing from placing certain metals or vias in sensitive analog regions.We typically use blockage layers to:

• Avoid routing over critical devices or matched components.
• Prevent density violations in specific regions.
• Maintain isolation and reduce coupling noise from nearby signal or digital lines.

I’d like to hear how you handle blockage layers in your projects. Do you define them manually, or do you rely on tools to generate them automatically? What best practices do you and your team follow? Feel free to share your experience, tips, or any challenges you’ve faced—your input can really help others in the community!