Version 6.1
May 15th 2002

CDF sensors specifications for RunIIbIntroduction
The CDF detector at the Tevatron Collider in Fermilab (Batavia, Illinois USA) will
undergo a new upgrade in order to be ready for the RunIIb data taking period (Jan 2005Dec 2007).
CDF will replace most of the present silicon detector system (the SVXII and L00 parts)
with a new single-sided based silicon detector capable of coping with a substantial
increase in the delivered luminosity by the Tevatron Collider.
We will base the new detector on single sided, AC-coupled, poly biased, microstripsilicon sensors P+/N, <100>, 6” material with different geometry and pitches. Alldetectors have one intermediate strip.
Total number of runiib silicon sensors is about 2,300.
They should be able to withstand a dose level of 1x1014 1 MeV equivalent neutron/cm2 sotheir characteristics should be similar to those already developed for CMS and CDF-L00.
Prototype and Production
Delivery of production sensors should occur between January 2003 December 2003 at a
rate of at least 200 detector per month. Option for a higher delivery rate should beevaluated and priced by the vendor.
In the present layout there are 4 different detector flavors:
type
Outer Axial
Small Angle stereo
Inner Axial
TOTAL

Production
Quantity
1512
648
144
2,304

Dimensions(mm)
96.392x40.550
96.392x43.100
78.5x14.850

Readout Pitch/pitch(um)
75/37.5
80/40
50/25

Production quantities may change as the detector design progresses. Above numbers arebest estimate at the moment. Nonetheless we are not expecting those numbers to besignificantly different from the final request.
We would like to prototype the Outer Axial and Small Angle Stereo detectors only(which represents more than 90% of the total number of silicon detectors).
Following specs are for the Prototype sensors. Even though we are estimating the final
sensor specs to be identical, small changes might be required.
We are not going to prototype the Inner Axial sensors, however, we have thosepreliminary sensor specs only for the purpose of getting production quantity quotes.

Sensor Specifications for CDF runIIb
Prototype Sensors
Required
Number of Outer Axial Sensors
Number of Outer Small Angle Sensors
Schedule

30 grade “A” and 30 grade “B”30 grade “A” and 30 grade “B”
delivery before 08/2002

WafersThickness
Wafer diameter
Wafer type (orientation)
Resistivity
Wafer warp

320 µm ± 15 µm
6 inchn-type (<100>)(see depletion voltage specs)
Vendor can specify what’s normallyachievable

Sensor general
Sensors are p+/n, single sided, AC coupled, poly biased silicon microstrip detectors withintermediate strips. Sensors need to withstand a dose of 1x1014 1 MeV equivalent
neutron/cm2 and an ionizing dose of 10 Mrad, consequently the high voltage operation
should exceed 500 V. All sensor have one floating strip such that the readout strip pitch is
twice the value of the strip pitch. All sensors have 3 µm overhanging metal except for theinner axial for which this value is ~1µm.
– Outer axial sensors have a strip pitch of 37.5 µm (readout pitch of 75 µm).
– The small angle sensors have strips at an angle of about 1.2 degrees with respect tothe axial (long side of the detector). Strips not reaching the short edge of the sensor
will be properly terminated at the edge of the active area on the long edge of thesensor.
– Inner axial sensors have a very fine pitch of 25 um (readout pitch is 50 µm).
Important Note:
You will receive final mechanical drawings for the Outer Axials sensors from Dr.
Kazuhiko Hara. We are still debating what angle to have for the SAS sensors (whichmay have a small impact on the width and pitch of the SAS sensors themselves).
Dr. Kazuhiko Hara will inform you as soon as this decision is taken and will provide
you with detail mechanical drawings. However you should start already with theOuter Axial prototype effort.
We don’t have yet final mechanical drawings for the Inner Axial sensors.
Preliminary specs are given only for the purpose of getting production quantity
quotes. We are NOT going to prototype the Inner Axial sensors.

Prototype Sensors
Specifications:aAxial: Active area dimensionsa
Axial: Overall dimensions
Axial: Strip Pitch
Axial: Readout Pitch
Axial: Number of Strips
Axial: Number of Readout Strips~ 40.5 x 95.4 mm240.550 x 96.392 mm2 (2 detectors per 6” wafer)37.5 µm75 µm1024512

Stereo: Active area dimensionsa
Stereo: Overall dimensions
Stereo: Strip Pitch
Stereo: Readout Pitch
Stereo: Number of Strips
Stereo: Number of Readout Strips~ 42.1 x 95.4 mm243.100 x 96.392 mm2 (2 detectors per 6” wafer)
40 µm
80 µm>1024
512

Inner Axial: Active area
dimensionsb
Inner Axial: Overall dimensions
Inner Axial: Strip Pitch
Inner Axial: Readout Pitch
Inner Axial: Number of Strips
Inner Axial: Number of Readout
Strips~12.9x78.5 mm2
14.850x96.392 mm2 (6 detectors per 6” wafer)
25 µm
50 µm
512
2561 mm is allowed from the active area to the physical edge of the sensor, but the active area can growlarger if less space is needed between the end of the active area and the physical edge of the sensor.
b
1 mm is allowed from the active area to the physical edge of the sensor, but the active area can growlarger if less space is needed between the end of the active area and the physical edge of the sensor.

Common Specifications:
Depletion Voltage
Biasing scheme
Poly resistor values
Passivation
Implant strip width
Implant depth
Doping of implant
Width of aluminum stripd
Thickness of Al strips
Resistivity of Al strips
Coupling Capacitor value
Coupling capacitor breakdown
voltage
Interstrip resistance
Total interstrip capacitance
Total sensor currente at T=20o C

Bad channels for grade “A”
Bad channels for grade “B”

cFrom 100 to 250 V (200V as upper limit
preferable)
Poly resistor (see drawings)c
1.5 ± 0.5 MΩ (<10% variation within a sensor)
SiO2 0.5÷1.0 µm thick~9 µm>1.2 µm> 1x1018 ions/cm3~15 µm (~11 µm for the inner axials)>1 µm<30 Ω/cm>10 pF/cm>100 V> 1 GΩ
<1.2 pF/cm (<1.5pF/cm total for the 90dgr)
grade “A”: <50 nA/cm2 at 500V
grade “B”: < 4uA/ cm2 at 350V and < 10uA/
cm2 at 500V
<1% (No more than 5 per sensor)<5% (No more than 25 per sensor)

Resistor on one side only is an equivalent option but has to be agreed with the customer because it canhave an impact on the active area dimensions and the positioning of the small angle stereo sensors.
dOnly readout strips will be metalized and will have bonding pads. Intermediate strips will have only DC
pad (see drawings for details).
e
For the grade “A” we would like to consider the option of a lower breakdown voltage value of 350V if itcomes with some cost saving. In other words the optional specs for the grade “A” detectors would read
350V instead of 500V.

Bad channels definition:
Parameter
Single strip leakage current at 500 V f
Coupling capacitor
Coupling capacitor
Coupling capacitor
Current through the Coupling
capacitor with 80 V across thedielectricRule> 10 nA> 1.1 times the typical value< 0.9 times the typical value>1.1 times the typical value
but the neighbors are normal>1 nA

ID of the defectLeaky
ShortOpenPH (pin hole)
PH (pin hole)

Above bad channel definition is based on measuring the coupling capacitance on eachstrip. We will consider other means of determining bad strips count based on vendor’s
proposal. Please attach a description of what measurement you would propose in order todetermine the bad strip count and location for each sensor.

Quality Control by manufacturer:
Value of the poly resistor
Value of the depletion voltageVisual inspection, verifying that no significant
scratches, blemishes and/or edge chipping arepresent
Total leakage current up to 1000 Vg (or until
current=20 µA)h in steps of 10 V.
Bad strips identification and count

Measured on Test
Structures on each wafer
Measured on Test
Structures on each wafer
Performed on each sensor

Measured on each sensor
Measured on each sensor

Quality Control results have to be provided to the customer on an electronic format aswell as on a paper format.

fThe measurement of strip leakage current of individual sensors is foreseen only for the prototypes. For
mass-production, based on the prototype data, the measurement will be made only for those sensors withthe total leakage current exceeding some criterion to be agreed upon.
gOr lower value if there is some instrumental limit. In any case at least up to 500V.
hWe can accept other values of voltage and/or current if more convenient for the manufacturer.