State of the art in Microfabrication

1. State of the art in Microfabrication Jurriaan Schmitz j.schmitz@utwente.nl -- www.utwente.nl/ewi/sc Jurriaan Schmitz - VLSI Photonics Workshop

2. Contents • Microelectronics: Moore’sLawtoday • Technology advances inside the microchip • Othermicrofabricateddevices • Prospectsforradiation imaging

3. Images: Computer history museum The beginning: 1960s 1968 Fairchild 2kT SRAM chip 1958 Fairchild First planar transistor 1965 Fairchild opamp 1962 RCA 16T logic chip 1961 Fairchild 4T5R flip-flop

4. Gordon Moore 1965 Transistors keep getting cheaper! Smaller components Bigger chips & wafers Better skills “Moore’sLaw”: The number of components on a chip doubles every year

5. Moore’sLaw – chips, accelerators, fusion… +Brilliance of synchrotron sources, # channels in trackers… “technologydrivenprogress”

6. How is Moore’s Law keeping up? GPU’s beat CPU’s Doubling per 2 years Components per chip Doubling per year Year

7. Moore’sLaw: perspective Transistor gate lengthscaling is slowing down (10% per generation) 300 → 450 mm transition is delayedto 2020 ITRS roadmap: multiple breakthroughsrequiredby 2018 … whathappens next?

8. Microchips keep gettingbetter Design gap Multicore processors Transistor performance boosters

9. Contents • Microelectronics: Moore’sLawtoday • Technology advances inside the microchip • Othermicrofabricateddevices • Prospectsforradiation imaging

10. The CMOS chip Complexity is more than transistors alone: A cm2chip maycontain ~20 km wires ~1010contacts

11. Transistor evolution1970-2000: “the happy scaling era” Poly Si gate SiO2 Silicon Intel Keep everything the same, onlyminiaturizeit: 1/√2 per generation

12. Transistor evolution (2)2000-present: new technologiesto boost performance Intel

13. Another performance booster:Permanent strain → activestrainmodulation Switch strain on and off Usepiezoelectricmaterial (e.g. PZT) High on-current& low off-current T. Van Hemert et al.., IEEE Trans. El. Dev. 2013 B. Kaleli et al., IEEE Trans. El. Dev. 2014

14. The art of microchips today Conventionalwisdom: “Ifyoucan do it in CMOS, do it in CMOS” “Ifyoucan do it in silicon, do it in silicon” • 1-nm precision manufacturing • Atomary sharp interfaces • High-purity materials • Best mastered: • Aluminum, copper, tungsten • Silicon; SiGe alloys • SiO2, HfO2, Si3N4

15. Emergingtechnologies in microelectronics:Replacinggoodoldsilicon Ge PMOS InGaAs NMOS AIST SelectiveGaN on Si Ultra-thinsemi-on-insulator LETI IBM

16. Emergingtechnologies in microelectronics:Replacing FLASH memory • Competitors: • Resistive RAM • Phase-change RAM • STT Magnetic RAM

17. But meanwhile, FLASH is going 3D

18. Contents • Microelectronics: Moore’sLawtoday • Technology advances inside the microchip • Othermicrofabricateddevices • Prospectsforradiation imaging

19. Microtechnology: more than chips Flat Panel Displays Photovoltaics Microfluidics Semiconductor lasers Light Emitting Diodes Sensors

20. Microtechnology: more than chips Steep market growth GaN-basedtechnology Hetero-epitaxy Haitz’ Law Flat Panel Displays Photovoltaics Microfluidics Semiconductor lasers Light Emitting Diodes Sensors

21. Microtechnology: more than chips High potential: Point-of-care medicine Internet-of-things Uses mainstream technology Flat Panel Displays Photovoltaics Microfluidics Semiconductor lasers Light Emitting Diodes Sensors

22. …and sensors forradiation imaging! Microfabricated sensors in particlephysics: Silicon detectors Charge-coupleddevices Siliconphotomultipliers CMOS-APS based detectors … Focus on semiconductors forsignalgeneration. Scintillators? Gas?

23. InGrid: a radiation imaging detector TimePix Al electrode SU-8 post Images: Nikhef Standard CMOS

24. Semiconductors on top of CMOS “TFA detector”, Andrea Francoet al., IEEE Trans. Nucl. Sci. 2012

25. Or vice versa? U.Twente LETI Stack thin-film transistors on your sensor Monocrystalline: 3D electronics as developed e.g. by LETI (Batude et al.) Polycrystalline: e.g. I. Brunets et al., IEEE Trans. El. Dev. 2009 Low temp fabrication (~400 °C) High interconnectdensity >> TSV’s

26. Advances in microfabrication:ConsequencesforParticlePhysics • Miniaturized detector systems mayboast • Improvedresolutionand speed • Reduced power consumption • LessX0, lowermass • Onboard intelligence • “The interconnect benefit” • IC Future: new materials & lower-power circuits • New semiconductor materials: GaN, InGaAs, Ge, … • Performance in radiation imaging?

27. Thank you: My coworkers at the University of Twente Nikhef Detector R&D group TIPP organizers Dutch Technology Foundation STW, Min. EconomicAffairs, FOM and EU

28. Questions? Jurriaan Schmitz - VLSI Photonics Workshop

29. Semiconductor market: arguably the largest industry

30. CPU clockfrequency RC bottleneck in the chip’s wiring wikipedia • The transistor count on a microprocessor has not increased since 2005. • The clock frequency “ “ “ “ • The transistor gate length has hardly reduced since 2005. • Chipworks: only 9% per generation lately, not 30% • 90, 65, 45, 32, 22, 15 nm CMOS

31. Trends likeMoore’s “Law” are notforever Passenger airplanes But airplanes got much better since 1960!

32. Inside a TriGate chip H5N1 virus (same scale) chipworks