Klayout 25d View
So open KLayout, enable OpenGL, assign a height to your metal3 layer, and tilt that view. Your next layout bug – or your next elegant solution – will reveal itself in the third dimension. About the author: This article is written for IC, MEMS, and PCB layout professionals using KLayout. For further reading, consult the official KLayout documentation under “2.5D View” and explore the user forum threads on setting realistic layer heights for your specific technology node.
For extremely large layouts (>10 GB GDSII), create a quick 25D view by first using Hierarchy > Flatten on selected cells, then reduce detail with Edit > Selection > Convert to polygons with a tolerance of 0.01 µm. Comparing KLayout 25D with Other Tools | Tool | 25D Feature | Cost | Best For | |------|-------------|------|-----------| | KLayout | Extrusion-based, OpenGL, live update | Free (GPL) | Quick visual checks, MEMS, small-to-medium ICs | | Cadence Virtuoso 3D | True 3D with material properties | $$$ Commercial | Advanced node full-custom IC | | Magic VLSI | Wireframe 3D, no shading | Free | Academic, very old hardware | | OpenROAD | No native 25D; requires external renderer | Free | RTL-to-GDS flows | | Klive (KLayout extension) | Experimental voxel-based 3D | Free | Research-grade volumetric analysis | klayout 25d view
| Aspect | Performance / Limitation | |--------|--------------------------| | Polygon count | Up to ~5 million polygons before frame rate drops. Beyond that, use View > 2.5D > Simplify to decimate. | | Texture memory | Each unique layer material uses texture memory. Group layers with identical height/color into one visual layer. | | True 3D navigation | You cannot view from below (z<0) or clip through layers. Elevation is capped at ~89°. | | No cross-sectioning | Can’t generate a live cut plane. For that, use the 2D cross-section tool separately. | So open KLayout, enable OpenGL, assign a height
