News about epitaxial silicon sensor

Attivita’ sul microvertice a Torino
Daniela Calvo
Commissione scientifica 3, Genova 21 settembre 2009
Micro-Vertex-Detector requirements
secondary
vertex
Beam pipe
p
p
0.1 mm
•
Good spatial resolution in r-phi
– Momentum measurement of
pions from D* decays
•
Good spatial resolution specially in z
– Vertexing, D-tagging
•
Good time resolution
– rms 6 ns (at 50 MHz clock)
with 2·107 ann/s
•
Triggerless readout
•
Energy loss measurement
– dE/dx for PID

Low material budget
– low momentum of particles
(from some hundreds of MeV/c)
(<1% X0 for each layer)
•
Radiation hardness (~4·1013 n 1MeV eq /cm2 )
(half year data taking, 15 GeV/c antip-p)
– Different radiation load
Primary
vertex
MVD layout
By G. Giraudo
By G. Giraudo
30 cm
40 cm
Custom Pixel Detector:
Micro Vertex Detector
4 barrels
Inner layers: hybrid pixels
Outer layers: double sided strips
and 6 forward disks
4 disks: hybrid pixels
2 disks: pixel and strips mixed
100 mm x 100 mm pixel sizes;
~ 1000 FE readout chip (114x110 pixels);
continuous data transmission without trigger
maximum event rate per cm2:
~ 12.3 MHz for pbar-Au at 15 GeV/c
max. chip data rate : ~ 0.8 Gb/s (40 bit/pixel)
energy loss measurement: time over
threshold;
dynamic range: 100 fC
Overview
Status of the activities for the pixel detector in Torino
Assembly layout
Electronics and cables
Mechanics and cooling
D. Calvo
Standard hybrid technology
THIN PIXEL SENSORS
(< 150 mm) realized with
EPITAXIAL SILICON
material (suggested by
Boscardin-FBK)
(At LHC: thickness of 200
mm; at RD50 diodes with
epitaxial material )
The thinning starts from this
side, reducing the substrate
to tens of mm.
silicon Cz substrate
epitaxial silicon layer
Several processes
for defining geometry
and for obtaining pixel sensors
are made on this side
r = 0.01÷ 0.02 W·cm
d = some hundreds of mm
r = 3 ÷ 4 KW·cm
d = 25 ÷150 mm
Bump bonding
readout chip
Carbon foam support
to improve
power dissipation
Carbon fiber
mechanical support
ASIC developed by the 130 nm CMOS technology
with triggerless readout.
Up to now the readout is in 250 nm CMOS technology
(see LHC experiment with trigger )
Cooling system
Assembly layout
Assembly scheme
2-chip module
Power cable
Data cable
Controller chip
0805 bias filter
capacitor
0603 supply filter
capacitors
Sensor
ToPiX readout chips
Multilayer bus structure
By R. wheadon
Layout of forward disks
By R. wheadon
Possibility of daisy-chaining controllers to save on cables (where data rates allow)
Controller chips serve two or three ToPiX readout chips
For outer layer of barrel would need to daisy-chain two 6-chip modules (power and controller chips)
to keep cables out of active region
Keeping cables out of active region means that some modules may require two designs according
to which end the cables have to be connected
Electronics and cables
Upgrade of ToPix
Technology LM -> DM (the HEP mainstream)
•
LM: 6 (thin) + 2 (thick) metal layers
•
DM: 3 (thin) + 2 (thick) + 3 (RF) metal layer
– RF layer shows lower resistivity and helps power routing
– RF layer gives more precise capacitance
– shared bus among adjacent columns
25 mm
100 mm
Upgrade of ToPix
Clock from 50 MHz to 160 MHz
– time stamp bin: ~6ns
– new columns and receivers to be redesigned
– new simulations
SEU protection: DICE cells -> triple redundance?
– twice size increase in the digital part of the chip -> rescaling of the analog part
Upgrade of the analog part of ToPix - I
Adaptation for the clock @ 160MHz
In order to keep the same clock_cylces to injected_charge ratio as ToPix2
(clock@50MHz), the discharging current value has to be proportionally increased
from 5 nA to 16 nA.
Simulation result of analog output signal
with the 2 different clock values
Qin
Clock
frequency
ToT
Clock
cycles
Clk_cy
/Qin
30 fC
50 MHz
6.094 ns
304
10.1
30 fC
160 MHz
2.000 ns
320
10.7
Upgrade of the analog part of ToPix - II
Compact leakage compensation stage
Layout compatible with the DM process
ToT (ms)
Baseline variation of 0.6mV when the
leakage current increases from 10nA to
100nA. (~2mV)
ToT variation due to the leakage current
Simulation: Qin = 80fC
dToT/dIleak=-1.53ns/nA
Leakage current (nA)
Results from radiation damage test of epi-diodes:
the radiation damage constant
Diode volume current
3
@ full depletion bias voltage [ A / cm ]
Equivalent fluence values on the diodes : 5.13x1013, 1.54x1014, 5.13x1014n(1MeVeq)/cm2
corresponding to 1, 3 and 10 years of PANDA lifetime
Pre-irradiation
1 year
3 years
10 years
1.E-01
1.E-02
1.E-03
1.E-04
1.E-05
1.E-06
1.E-07
1.E-08
Epi-50
Epi-75
Epi-100
The radiation damage constant is
a = DJ/F = 7.6(0.3)x10-17 A/cm for all diodes.
Lekage current < 50 nA/pixel (100 mmx100mm size, 100 mm thick)
R&D – electronics and connections
Development in progress with prototypes
Readout chip
Detector
Study of the architecture in progress
( test of high frequency cable)
Module controller
to counting room/daq
cable
Optical
transceiver
PCB -BUS
Development in progress in other collaboration
First prototypes
Preliminary bus scheme
By R. Wheadon
Cable prototype – testing board layout
1 m differential cable
Al
Al
Kapton
(SU8)
pads
connectors
Cable prototype –preliminary simulation
By Paolo De Remigis
Updates from pixel cooling
Responsible: S. Coli
INFN - Torino
Results from test
New prototype done
 12 resistors on 4 rows, 2 rows x side
 “disk body” by POCO-HTC foam
 2 tubes embedded (øe2mm, øi1.84mm)
COOLING TEST RESULTS –IR IMAGES
TEMPERATURE PROFILE
Results from simulations
POCO-HTC K (75, 245, 245) W/mK
FEM RESULTS
1 W/cm2
INPUT DATA
0.3 ℓ/min
water 18.5 oC
Cooling system for disks
Disk split in two halves along the mid-plane
Material for heat dissipation: foam POCO-HTC
Embedded cooling capillary between the two halves
All elements grued with thermal glue
Problem: large glueing area -> test have to be performed
Results with different material for cooling
POCO FOAM
Density: 0.55 g/cm3
POCO HTC
Density: 09 g/cm3
Pyrolytic Graphite
Density: 2.2 g/cm3
Max. Reached Temperature
Poco Foam: 23°C
POCO HTC: 21.7°C
PG: 23.3 °C
Total power: 90 W
Coolant Temperature: 20°C
Cooling pipe scheme
1 tube Ø6
2tubes Ø8
4 manifolds 41
1 manifold 21
6 tubes Ø6
6xØ4
1 manifold 61
2xØ4
6xØ4
2 manifolds 41
1 manifold 61
2xØ4
1 manifold 21
6xØ4
6xØ4
By B. Giraudo 1 tube Ø6
2tubes Ø8
1 manifold 61
1 manifold 61
Updates from MVD Mechanics
Responsible: G. Giraudo
INFN - Torino
MVD layout
>250 mm
Ø 20.4 mm
Fittings for cooling pipes
Ancillary parts as special fittings and curves can be
common parts made from Ryton R-7-220 by injection mould
7 mm diameter
16 mm length
3 bar maximum pressure
Mechanics details
~1,3 mm
Primary target
Responsible: F. Iazzi
Politecnico and INFN - Torino
Primary target
Al
The target will be built through the following steps:
Step 1
The target production starts from a disk shaped basis of Cu,
(sizes:14mm diameter and 0.5 mm thickness), on which a carbon layer
20 mm thick will be deposited
Remarks:
•the density of the layer is not the graphite density, but close to that: it
will be measured (we will use the back-scattering technique)
•the thickness of the layer can be chosen without major constraints in
the range 10-40 mm and will be measured by optical techniques with
good precision (better than 5%), after the deposition
Step 2
After the deposition the carbon layer will be masked along the wires
and the rest of the carbon will be wet-etched and taken away. The
result will be a Cu disk having 3 wires of about 14 mm x 20 x 20 mm2
glued on.
The distances between the 3 wires could be 3.5 mm in order to avoid
the beam spot overlapping on 2 wires
Step 3 (see fig. 2, where the ring is in violet, wires in black/white)
The Cu disk will be wet etched and taken away unless a ring (external
diameter 14 mm, internal 12 mm), which will be previously masked.
The result will be a ring with 3 C wires like a guitar.
Step 4
The Cu ring with wires will be inserted inside a Al local frame, whose
aim will be to manage the plugging of the target into the beam pipe
14
13
15
C
side view
frontal view
Cu
.5
6
13
14
2.5
3.5
3.5 2.5
1
5
2
1
4
Next step and conclusions
Richieste capitolo Missioni Interne
Richieste capitolo Missioni Estere
MISSIONI ESTERE:
•Partecipazione ai 4 meetings di collaborazione con cariche ufficiali: 4 pp al Coordination
Board: (Calvo, Filippi, Marcello, Iazzi) e 1 pp al Technical Board (Calvo) (i meeting generali
sono programmati a 5 gg). 5gg+viaggio x 4 meetings x 5pp: 25 keuro
•Partecipazione ai meetings del microvertice e della meccanica dell’esperimento con presenza
del coordinatore meccanica mvd (G. Giraudo) e responsabile cooling ( S. Coli) e partecipanti
al FEE tag (D. Calvo e A. Rivetti). 3gg +viaggio x 7 meeting x 3 pp: 13 keuro
•settimana di lavoro a Julich per microelettronico con sviluppo logica di controllo in
collaborazione. 5gg+viaggio x 1 p: 1.5 Keuro
•lavoro di integrazione della meccanica e del cooling dei pixel e delle strips intorno alla beam
pipe e targhetta, con il routing (1 sett. a Julich, 1 sett.a Bonn, 1 sett.al GSI). 5gg+viaggio x 2
pp x 3 incontri: 5 Keuro
•contatti scientifici del responsabile locale mvd con il responsabile mvd a Bonn, per scrittura
TDR. 4 gg+viaggio x5 contatti x 1p: 3 Keuro
•2 Physics meetings ( Iazzi e’ partecipante). 2gg+viaggio x 2 contatti x 1 p:1.5 keuromeetings
di aggiornamento software di una settimana per 2 persone presso GSI. 5
•gg+viaggio x 1 corso x 2 pp: 3 keuro
•dottorando al GSI per lavoro sulle simulazioni, circa 10 giorni: 1.5 keuro
•contatto con Fraunofher Institute per bump bonding dei sensori. 2gg+viaggio x 1p: 1.5 keuro
•contatti scientifici con gruppi europei (fisica e tecnologia). 3 gg+viaggio x 3 contatti x 2 pp: 3
keuro
•1 settimana di progettazione meccanica della regione ipernucleare- beam pipe a Julich. 5
gg+viaggio x1 pp: 1 Keuro
•Meeting per sviluppo targhetta e beam pipe per la parte ipenucleare. 2gg+viaggio x 2 contatti
x 1 p:1.5 keuro
•partecipazione a due congressi internazionali per presentare i risultati del mvd: 5 gg+viaggio x
1p x 2 congressi: 3.5 keuro
•test TID con X al CERN per ToPix3 ( sj alla disp. sorgente e chip). 7gg+viaggio x 1 misura x 2
pp: 2 keuro
•test con protoni (circa 23 GeV) per studiare i sensori epi (sj all’ass.fascio) con spessore fino a
100 micron. 7gg+viaggio x 1 misura x 4pp, compresa installazione: 4 keuro
•test a Bonn (elsa) di radiation lenght di carbon foam ( sj. ass fascio): 5gg+viaggio x 1 misura x
2 pp: 2.5 keuro
Totale M.E.: 62.5 kEuro + 8.5 kEuro sj
Richieste capitolo CONSUMO
sj
sj
Richieste capitolo INVENTARIO
f.t.e. nel 2010 a Torino
Calvo Daniela: 80%
Busso Luigi: 30%
De Mori Francesca: 20%
Filippi Alessandra: 30%
Marcello Simonetta:70%
Kugathasan Thanushan: 100%
Szymanska Katarzyna: 100%
Iazzi Felice: 100%
De Remigis Paolo (elettronica): 60%
Mazza Giovanni (microelettronica):30%
Rivetti Angelo (microelettronica):20%
Wheadon Richard (sensori/elettronica):20%
Coli Silvia (meccanica/tecnologia):70%
Giraudo Giuseppe (meccanica/tecnologia):70%
= 8fte
E personale tecnico INFN-Torino
Laboratorio di Elettronica e Laboratorio
tecnologico/Officina meccanica