1. TSV: Via lining & filling sami.franssila@aalto.fi

3. TSV degree of difficulty www.yole.fr, 2010

4. Basic via structure Benfield

5. Process flow Benfield

6. Profile & filling options

7. Profile & step coverage

8. Dielectric requirements IEEE 2009 3D system integration conference

9. Resistance

10. Why is thinning needed? Step coverage of sputter? – Maximum aspect ratio ~ 5 – Tapering makes sure the seed is continuous – W_bottom=20um, t=650um wafer -> w = 134um -> pitch ~ 200um Pitch < 100 – > wafer has to be thinned down

12. Silicon vias Silex

13. Silicon vias Silex

17. Epoxy-lining

18. Filling with sacrificial support

19. Packaging with TSV cap wafer

20. Wire bonding via metal

21. Via electrical results

22. Nickel wire magnetic assembly Fischer, Roxhed:

23. Ni wire process flow Fischer, Roxhed:

24. Solder filling

26. Copper ball filling

28. TSV filled by CNTs

31. CNT growth