Optimization is just science
Engineers who 'just tweak things until it works' are slower and worse than engineers who follow a method. The method below is borrowed straight from the scientific method and applied to chip design. Five steps. Repeat until done.
The five steps
1. Identify the weakest metric — sort by distance from target, not by absolute number. 2. Determine the root cause — material? geometry? coupling efficiency? 3. Generate 2–4 hypotheses — each one a single, testable change. 4. Test each hypothesis independently — one change, one re-test, record the delta. 5. Combine the winners — re-test the composite. (Sometimes wins don't add — that's information too.)
Practice — fill in the loop
Use the worksheet below to walk a real design through the loop. Pick any test result you don't like, and complete each step. The widget marks the loop complete only when every step has substantive content.
Exercise — fix a deliberately bad design
Open the Chip Builder. Build (or load via Templates if available) this deliberately weak design:
- Substrate: Silicon - Channel: Silicon (low mobility for our target) - Gate: Metal Gate on SiO₂ (no piezo) - No GAA wrapper - No EM antenna - Wide channel, thick oxide
Run the Switching Speed and Power tests. They will be poor. Apply the 5-step loop until every metric is green. Use the widget above to track your steps. Target: switching speed ≥ 1.5× the starting value AND power ≤ 0.7× the starting value.
- Apply the scientific method to chip optimization.
- Five steps: identify weakest → root cause → hypotheses → test → combine.
- Change one variable at a time. Re-test after each change.
- Take a deliberately bad design and make every metric green.