Extreme ultraviolet lithography : Pushing microchips down to the nanoscale

1. Extreme ultraviolet lithography :Pushing microchips down to the nanoscale A Wojdyla Center for X-Ray Optics - LBNL December 12th, 2013

2. There’s plenty room at the bottom • I don't know how to do this on a small scale in a practical way, but I do know that computing machines are very large; they fill rooms. Why can't we make them very small, make them of little wires, little elements – and by little, I mean little. For instance, the wires should be 10 or 100 atoms in diameter, and the circuits should be a few thousand angstroms across. – Richard Feynman (1959) EUV Lithography - All Talk Considered

3. Transistors • They are electron taps ! • Relays & vacuum tubes (“analog”) • Solid state transistors (“digital”) EUV Lithography - All Talk Considered

4. What is lithography ? • (Photo) lithography • “To write in stone” • lithos (λίθος) “stone” • graphein (γράφειν) “to write” EUV Lithography - All Talk Considered

5. How do you make microchips ? (1/2) Inverted microscope Source : Mack book EUV Lithography - All Talk Considered

6. How do you make microchips ? (2/2) Source : Mack book x 30 Intel Core source : Intel EUV Lithography - All Talk Considered

7. For, in order to work iron, a hammer is needed,and the hammer cannot be forthcoming unless it has been made; but, in order to make it, there was need of another hammer and other tools, and so on to infinity – Spinoza How do we make them ? • We don’t actually make microchips,but we provide the tools to make them A crane, as seen from the CXRO coffee room EUV Lithography - All Talk Considered

8. Moore’s law “Where a calculator on the ENIAC is equipped with 18,000 vacuum tubes and weighs 30 tons, computers in the future may have only 1,000 vacuum tubes and perhaps weigh 1.5 tons.” - Popular Mechanics (1949) Source : ASML EUV Lithography - All Talk Considered

9. Resolution is limited by the wavelength • Resolution is limited by the wavelength EUV Lithography - All Talk Considered

10. Why would you use Extreme UV ? • Current wavelength : 193 nm (excimer) • Go very low in resolution • Use of multi-patterning : • lots of masks : lower yield, higher costs • New wavelength : 13 nm • 15x smaller wavelength • Materials are available xkcd EUV Lithography - All Talk Considered

11. Challenges for EUV Lithography source : Cymer • Source • Cyclotrons, FEL, Z-Pinch, Laser-Produced Plasma • Works in vacuum • Optics • Only in reflection • Coating (thin film) • Materials • Appropriate polymers source : ALS EUV Lithography - All Talk Considered

12. A sense of scale (1/2) • 8 nm feature size • Compare it to the size of a red blood cell : 8μm • Compare to the width of a DNA strand : 2.3 nm • Compare it to the size of an atom (12C) : 0.2 nm (VdW) source : CXRO EUV Lithography - All Talk Considered

13. 10 μm EUV Lithography - All Talk Considered

15. A sense of scale (2/2) • 0.1 nm precision (~λ/100)over the size of a mirror • 1mm precision over the size of Pacific ocean “Oh man, it’s raining !” EUV Lithography - All Talk Considered

16. Every perturbation is the enemy • Pollutants • Vacuum compatibility • Clean room (dust) • Vibrations • “calm environments” already shake 1000x too much ! • Heat • Aluminum’s CTE: 22 μm/m/K ->Metrology is the key “If you can measure it, you can make it.” Effects of the dielectric permittivity of air vs. vacuum (A Wojdyla, CXRO) Influence of temperature on the measurements (A Wojdyla, CXRO) Photon-noise limited experiments (CN Anderson, CXRO) EUV Lithography - All Talk Considered

17. Getting indust-real • First industrial tools shipped • 18nm resolution ASML NXE:330 Demo tool EUV Lithography - All Talk Considered

18. Berkeley-Sematech MET 0.5NA • To renew the current Micro Exposure Tool (MET) • 0.5 Numerical Aperture -> 8 nm resolution Sematech members : ASML, IBM, Intel, Texas Instruments,… Berkeley Sematech MET 0.5NA EUV Lithography - All Talk Considered

19. EUV Lithography - All Talk Considered

21. Designing, simulating, prototyping, tolerancing wafer leveling system wavefront sensing optical prototype

22. Conclusions • Next step in semi-conductor industryis EUV lithography • It’s not easy, because we have to overcomeNature’s fundamental limits (so do you!)and environmental factors • We’ve reached the bottom • What’s next in tech ? • 3D chips, graphene transistors, spintronics, quantum computers… xkcd EUV Lithography - All Talk Considered

23. Thank you for your attention more at cxro.lbl.gov/MET contact : awojdyla@lbl.gov

25. Drawing from Nobel prizes