Transcript Test of One ALICE Pixel Assembly in the NA48 beamline

Test of One ALICE Pixel
Assembly in the NA48 Beamline
Wednesday, June 16 - Thursday, June 17, 2004
Chip and Sensor Characteristics
P. Riedler/CERN
ALICE
ALICE Pixel - Test Beam Setup
ALICE SPD carried out test beams in 2001, 2002, 2003 in proton and heavy
ion beams at the SPS using a specially developed DAQ system:
One plane installed for NA48:
• 1 ALICE assembly
• 1 DAQ adapter card
• 30 m DAQ cables
• 30 m JTAG control cables
• LV and HV power supplies
• VME crate with r.o. module (Pilot) and
JTAG controller
• JTAG multiplexer
• MXI interface to PC
• ALICE PTS software (LabView)
ALICE TB 2002 setup with 3 DAQ planes
and 5 assemblies
P.Riedler/CERN
PC remotely controlled from NA48
control room
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ALICE pixel team members helping with the
preparations and the test:
Mike Burns
Peter Chochula
Fadmar Osmic
DOCT
Alex Kluge
Petra Riedler
PJAS
P.Riedler/CERN
Michel Morel
Giorgio Stefanini
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Schematic of a Hybrid Silicon Pixel Detector
Readout Chip
Bump Bonds
Sensor
P.Riedler/CERN
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ALICE Pixel Chip
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•
•
•
0.25µm CMOS process
radiation tolerant design
clocked at 10MHz
8192 pixel cells with digital
output
• ~100 µW/channel
• ~1000 e- mean threshold
13.5 mm
15.8 mm
(~200 e- RMS
•~13 mio. transistors
1200 ALICE Pixel Chips will be
used in the SPD (Silicon Pixel
Detector)
50 µm x 425 µm pixel cell
P.Riedler/CERN
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ALICE chip wafer
Native thickness 725 µm
Produced by IBM
Wafer material:
“electronics grade” 8 in. silicon wafers
Each chip needs to be tested before the wafer is sent for bump
bonding.
According to a KGD (Known Good Die) map only those chips that fulfill all
test criteria are used for bump bonding.
KGD yield on ALICE chip wafer: ~55% (86 chips per wafer in total)
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ALICE Sensor
1 ALICE silicon sensor is
connected to 5 ALICE readout
chips via 40960 bump bonds
Sensor thickness: 200 µm
Wafer material:
High resistivity FZ 5 in. wafer
Pixel size: 50µm x 425µm
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Bump Bonds
Pb-Sn Bump Bond
25µm
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Material Budget
Requirements for ALICE:
<1 % X0 total per pixel layer
e.g.
200 µm thick sensors
Chip wafers thinned to 150µm
after bumping
Multilayer kapton bus with Al
J. Salmi/VTT
Presentation at BOND’03 workshop, CERN, June 2003
P.Riedler/CERN
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Thinned Chip Wafers (10-30 µm)
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
P. Mikulik et al, http://www.xray.cz/xray/csca/kol2002/doc/petr_mikulik.htm
P.Riedler/CERN
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Radiation Effects in Silicon
Surface Damage
Bulk Damage
Electronics
Detectors
Full bulk is
sensitive to
passing
charged
particles
Sensitive
components
are located
close to the
surface
P.Riedler/CERN
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Estimation of the Radiation Effects for Future NA48
VERY PRELIMINARY!
Fluence:
Assuming 5000 spills/day, 50MHz particles/cm2/spill and a spill length of 4.8s:
1.2E12 particles/cm2 per day
Assuming pion beam:
feq= kf
k…hardness factor (9GeV pions:3.6, flat dist.)
feq=4.32E12 (1 MeV neutrons)/cm2 per day
Assuming 100 days of running:
feq= 4.32E14 (1 MeV neutrons)/cm2 per run
>> Leakage current, depletion voltage, signal, operating conditions,….
Dose: 4.32E14/(6.24E9/(1.66 MeV g-1 cm2))=114kGy=11.4Mrad
P.Riedler/CERN
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Single Chip ALICE Assembly tested in NA48
•150µm thick ALICE chip
•200µm thick sensor
Mounted on a thin test-PCB
Vfd=15V
Vop=30V, 50V
8192 pixels
Produced 2003, tested in
ALICE p-TB 2003
Sensor
Chip
P.Riedler/CERN
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Timeline of the Test in NA48
Preparations:
May/June 2004:
Installation of one ALICE SPD testbeam plane in the NA48 lab
Beam:
Wednesday, June 16:
Installation in the beamline at the position of KABES2
Begin of data taking
Thursday, June 17:
End of beam at about 14.00, reinstallation of KABES2
~140 MB data taken (SPD TB 2003, HI run, 3 weeks: 3GB)
P.Riedler/CERN
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More on the tests:
see talk by M. Martini
P.Riedler/CERN
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