1. Nikhef Annual Meeting 13 Dec 2001 Future Vertexing Els Koffeman for Nikhef Vertex Group

2. dec 2001els koffeman2 Topics No report on Zeus, Hermes, Alice, LHC-B, Atlas in spite of much progress No report on beautiful infrastructure R&D vertex detectors –Very High Luminosity Hadron Colliders Extreme radiation hardness (1x 10 16 /cm -2 ) –Linear Colliders High precision (1-5 micron point resolution) Low material (0.1 X 0 per layer) ‘small’ detectors Medipix Time Projection Chamber

3. dec 2001els koffeman3 Electronic Department Recent projects –Alice: analoge buffer/line driver, digital control ic (jtag + glue logic), power supply is prevented for single event latchup –LHCB: analog line driver en comparators voor beetle chip –pixel: 4 bits adc per pixel –zeus: fail safe token voor helix –general: low noise amplifier Four FTE engineers working on VLSI Education –EPFL (Lausanne) –Advanced Analog IC Design (5 people) –Advanced Digital IC Design (3 people) –Practical Aspects in Analog & Mixed Mode ICs (3 people) –Transistor-level Analog IC Design (2 people) –expected: low voltage analog IC (2 people)

4. dec 2001els koffeman4 N P Quick Reminder Silicon as a sensor –300 micron thick wafer –High resistivity, purity –Surface strips, pixels, pads Silicon as readout –Poor quality wafer –Photolitography makes Integrated Circuits –All structure contained in few micron thickness –Most important component is transistor –Current technology ‘CMOS 0.25 micron’ P Silicon pixel,pad,strip gate contact

5. dec 2001els koffeman5 Signal!

6. dec 2001els koffeman6 Crystal Damage ! (vacancy, interstitials) Charge generation Inside CMOS! Leakage currents Need High Voltage Less collected charge Transistor performance degrades Chip ‘blows up’

7. dec 2001els koffeman7 R&D vertexing CERN –RD 19 Pixels –RD 39 Cryogenic operation of silicon –RD 42 Diamond detectors –RD 48 ROSE radhard silicon –RD 49 Radhard Electronics –Proposal for new R&D group LCFI (linear collider flavour identification) –CCD detector for TESLA –8 UK institutes, CERN, SLAC MIMOSA –Monolithic pixels –Proposal submitted to DESY PRC –Strassbourg, Geneve, Nikhef, Liverpool, Glasgow, RAL, …

8. dec 2001els koffeman8 Radiation Hardness of Silicon The leakage current damage parameter is material independent Radiation damage very different for different particles (expressed in hardness factor K) –24 GeV protonsK =1 –Slow neutronsK=0.9 –Fast neutronsK=1.7 –Gamma 60-CoK=2x10-6 ‘Effective doping changes’ (or increasing depletion voltage) improved by oxygenation of the material A macroscopic damage parameter model has been developed which can be used to predict detector parameters in a given radiation environment including annealing effects

9. dec 2001els koffeman9 Radiation harder with oxygen? Two methods were found to highly oxygenate silicon. – Firstly, at the ingot growing stage. – Secondly by diffusion of oxygen into ANY wafer using a high temperature drive-in – Technology has been successfully transferred to several silicon detector manufacturers (SINTEF,Micron, ST, CIS) and full-scale microstrip detectors have been produced.

10. dec 2001els koffeman10 Pixel systems MCM multi chip module –‘traditional’ 300 um thick pixel sensor bump bonded to a chips with amplifiers and readout. CCD –Charge collection in thin surface layer –charge transferred through the wafer Monolithic pixel –use standard CMOS wafer –simple readout per pixel sensor chip sensor Surface sensor

11. dec 2001els koffeman11 Monolithic Pixels No depletion layer charge diffusion only < 1000 electrons cell = Monolithic:part of the CMOS is used as detector element Will it work ?

12. dec 2001els koffeman12 MIMOSA - I 4000 pixels ! 1.2 x 1.2 mm2

13. dec 2001els koffeman13 MIMOSA Signal / noise = 40 Efficiency = 99% Resolution NIKHEF proposed a ladder ‘concept’ thickness 0.05 mm 12 cm long 3 x 2 cm wide 0.9 g silicon 0.8 g support

14. dec 2001els koffeman14 Diamond – Pixel detector

15. dec 2001els koffeman15 Medipix- recent developments Chip Design (0.25 mm) (TMR EU project) –DAC's for Alice/LHCb chip (radhard) –DAC's for Medipix2 chip MUROS2 Interface for Medipix2 Multi-Chip Board for 2x4 multichip Medipix2 imager Dynamical Defectoscopy –micro-crack development in Aluminium (Marie Curie EU project)

16. dec 2001els koffeman16 Multi-Chip Board MUROS2 Chipboard 8 ASIC chips Medipix2 chip size 14 x 16 mm 2 1 Sensor 28 x 56 mm 2 (fully sensitive area) 512 x 1024 Pixels of 55 x 55 mm 2 (0.5 Megapixel) Prototype, useful for e.g. Small Animal Imaging V bias SCSI-5 Cable 160 Mhz LVDS PC+DIO 10 Mhz

17. dec 2001els koffeman17 3 different micro ADC's <100 x 100 mm area <1 mW power David San Segundo Bello

18. dec 2001els koffeman18 Chipboard Top layer metal High Density Interconnect Technology 9 metal layers (5 in kapton build-up) 1840 staggered m-via's 366 drilled-through via's 80 SMT capacitors

19. dec 2001els koffeman19  1mm Hole 7 X-ray Defectoscopy SiGaAs Si + FlatField Correction 5 mm 0.5 mm

20. dec 2001els koffeman20 TPC for a linear collider Traditional TPC: signal collected on wires Principle of GEM introduced by Sauli Used in conjunction with MSGC’s or plain electrodes New idea: get the electrons directly in a chip! (Harry v.d Graaf, Jan Visschers, Erik Heijne ) If successful (with 60 *60 micron pitch) –Resolution limited by diffusion –Optimise gas max for this –Much better track separation –Can improve all time favorite Aleph TPC with 30-40 %

21. dec 2001els koffeman21 TPC + medipix chip GEM Medipix chip kathode ~ 1mm~ 1m Sensitive area

22. dec 2001els koffeman22 TPC plans Build proto type If charge measured = > connect to Medipix chip. Develop prototype for TESLA…. Need 15 m 2 of chips!

23. dec 2001els koffeman23 Conclusion…. Medipix Diamond CMOS sensors micro-electronics Novel TPC R&D is in good shape we need a vertex group !Do we need a vertex group ? R & D

24. dec 2001els koffeman24