1. VLSI Design Lecture 4-b: Layout Extraction Mohammad Arjomand CE Department Sharif Univ. of Tech.

2. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 2 of 50 n Layout can be very time consuming  Design gates to fit together nicely  Build a library of standard cells  Must follow a technology rule n Standard cell design methodology  V DD and GND should abut (standard height)  Adjacent gates should satisfy design rules  nMOS at bottom and pMOS at top  All gates include well and substrate contacts Gate Layout

3. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 3 of 50 Example: Inverter

4. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 4 of 50 Layout using Electric

5. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 5 of 50 n Horizontal N-diffusion and p-diffusion strips n Vertical polysilicon gates n Metal1 V DD rail at top n Metal1 GND rail at bottom 32 by 40 Example: NAND3

6. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 6 of 50 Example: NAND3

7. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 7 of 50 n Stick diagrams help plan layout quickly  Need not be to scale  Draw with color pencils or dry-erase markers Stick Diagrams

8. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 8 of 50 Stick diagrams help plan layout quickly Need not be to scale Draw with color pencils or dry-erase markers Vin Vout VDD GND Stick Diagrams

9. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 9 of 50 n A wiring track is the space required for a wire  4 width, 4 spacing from neighbor = 8 pitch n Transistors also consume one wiring track Wiring Tracks

10. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 10 of 50 Wells must surround transistors by 6  Implies 12 between opposite transistor flavors  Leaves room for one wire track Well spacing

11. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 11 of 50 n Estimate area by counting wiring tracks  Multiply by 8 to express in Area Estimation

12. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 12 of 50 n Sketch a stick diagram for O3AI and estimate area  Example: O3AI

13. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 13 of 50 n Sketch a stick diagram for O3AI and estimate area  Example: O3AI

14. Modern VLSI Design 4e: Chapter 2 Sharif University of Technology Slide 14 of 50 n Sketch a stick diagram for O3AI and estimate area  Example: O3AI