Physical Verification Basics

1. Design Rule Check (DRC)

DRC ensures your layout can actually be manufactured. It checks geometric constraints imposed by the foundry's lithography process.

• Min Width: Wires too thin may break during fabrication (Open circuit).
• Min Spacing: Wires too close may bridge together (Short circuit).
• Enclosure: Vias must be fully covered by metal to ensure good contact.

2. Layout Versus Schematic (LVS)

LVS verifies that the physical layout corresponds exactly to the electrical schematic (netlist). It extracts devices (transistors, resistors) and connections from the shapes and compares them graph-to-graph.