Vertexing & Tracking Detectors LOCAL MECHANICAL SUPPORTS AND COOLING SYSTEMS
Nikhef Annual Meeting 13 Dec 2001 Future Vertexing Els Koffeman for Nikhef Vertex Group.
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Transcript of Nikhef Annual Meeting 13 Dec 2001 Future Vertexing Els Koffeman for Nikhef Vertex Group.
Nikhef Annual Meeting13 Dec 2001
Future Vertexing
Els Koffemanfor
Nikhef Vertex Group
dec 2001 els koffeman 2
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 1016 /cm-2)
– Linear Colliders• High precision (1-5 micron point resolution)
• Low material (0.1 X0 per layer)
• ‘small’ detectors
• Medipix• Time Projection Chamber
dec 2001 els koffeman 3
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)
dec 2001 els koffeman 4
NP
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
dec 2001 els koffeman 5
Signal!
dec 2001 els koffeman 6
Crystal Damage !(vacancy, interstitials)
Charge generationInside CMOS!
Leakage currentsNeed High VoltageLess collected
charge
Transistor performancedegradesChip ‘blows up’
dec 2001 els koffeman 7
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, …
dec 2001 els koffeman 8
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 protons K =1– Slow neutrons K=0.9– Fast neutrons K=1.7– Gamma 60-Co K=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
dec 2001 els koffeman 9
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.
dec 2001 els koffeman 10
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
dec 2001 els koffeman 11
Monolithic Pixels
• No depletion layer• charge diffusion
only• < 1000 electrons• cell =• Monolithic:part of
the CMOS is used as detector element
• Will it work ?
2μm 20 x 20 μm 10
dec 2001 els koffeman 12
MIMOSA - I
4000 pixels !
1.2 x 1.2 mm2
2μm 20 x 20
dec 2001 els koffeman 13
MIMOSA
Signal / noise = 40
Efficiency = 99%
Resolution μm 1.8
NIKHEF proposeda ladder ‘concept’thickness 0.05 mm12 cm long3 x 2 cm wide
0.9 g silicon 0.8 g support
dec 2001 els koffeman 14
Diamond – Pixel detector
dec 2001 els koffeman 15
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)
dec 2001 els koffeman 16
Multi-Chip Board
MUROS2 Chi
pboa
rd
8 ASIC chips Medipix2 chip size 14 x 16 mm2
1 Sensor 28 x 56 mm2 (fully sensitive area)
512 x 1024 Pixels of 55 x 55 mm2 (0.5 Megapixel)
Prototype, useful for e.g. Small Animal Imaging
Vbias
SCSI-5 Cable160 Mhz LVDS
PC+DIO
10 Mhz
dec 2001 els koffeman 17
3 different micro ADC's
<100 x 100 mm area<1 mW power
David San Segundo Bello
dec 2001 els koffeman 18
Chipboard Top layer metal
High Density Interconnect Technology9 metal layers (5 in kapton build-up)1840 staggered m-via's 366 drilled-through via's 80 SMT capacitors
dec 2001 els koffeman 19
1mm Hole 7
X-ray Defectoscopy
Si GaAs
Si + FlatField Correction
5 mm 0.5 mm
dec 2001 els koffeman 20
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 %
dec 2001 els koffeman 21
TPC + medipix chip
GEM
Medipix chipkathode
~ 1mm
~ 1mSensitive area
dec 2001 els koffeman 22
TPC plans
• Build proto type• If charge measured
= > connect to Medipix chip.
• Develop prototype for TESLA….
• Need 15 m2 of chips!
dec 2001 els koffeman 23
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
dec 2001 els koffeman 24