First Proton Irradiation of CMS Sensors

W. de Boer, A. Dierlamm, A. Furgeri, E. Grigoriev, F. Hartmann,

F. Hauler, L. Jungermann, Ch. Piasecki

Some facts to remember for the next slides

• Data is preliminary• Measurements and evaluation was done in

4 days only including the weekend some plots can be arranged in a better way and the data is incomplete! (sorry!!!)

• The biasing was done with conductive rubber residuals on AC pads sometimes gives contact problems

• We used the testing of the teststructures to train personal

• After irrad.: Strip scan for ST at Vbias=900V (it was stable)

• The evaluation is not complete!

Materials

• Hamamatsu Full Sensor (W6b 4919-39)Thickness: 500 mResistivity: 4.6 kcm

• Hamamatsu teststructures (same batch no. 35-41)– Have to look up all other parameters according

to the HPK tables

• ST Full Sensor (04439218)Thickness: 500 mResistivity: 5.1 kcm

Simulated LHC conditions with respect to surface damage!

Bia s ring--> G ND

Rp o ly

DC

ACSho rt a ll DC to b ia s (G ND)

Ba c kp la ne to + Vb ia s

Rp o ly

DC

C C

AC

He re we ne e d p o te ntia l like in LHC 1M a t 1 A = 1V

Rp o lyC urre nt a fte r irra d

Vbias

Irrad. Assembly

IV and CV on both Sensors

0 50 100 150 200 250 300 350 400 450 500 550 600

0,00

0,05

0,10

0,15

0,20

0,25

0,30

0,35

0,40 0 50 100 150 200 250 300 350 400 450 500 550 600

0,1

1

10

IV and CV on FS

Hamamatsu ST

Cap

acita

nce-0

.5

Bias Voltage [V]

Hamamatsu STLe

akag

e C

urre

nt [

A]

Strip Parameters on Ham. Sensor

0 100 200 300 400 500 600

0,2

0,4

0,6

0,8

1,0

1,2

1,4

0 100 200 300 400 500 6001,0

1,5

2,0

2,5

3,0

0 100 200 300 400 500 600

460

480

500

520

540

560

580

600

0 100 200 300 400 500 6003,10

3,15

3,20

3,25

3,30

Ileak [nA] Rpoly [M]

Ccquasi [pF]

Hamamatsu Sensor 39

Cint [pF]

Interstrip capacitance of HPK sensor (1 neighbour)

100 fF

Strip Parameters on ST Sensor

0 100 200 300 400 500 600

1

10

100

1000

0 100 200 300 400 500 6001,0

1,2

1,4

1,6

1,8

2,0

2,2

2,4

0 100 200 300 400 500 600

560

580

600

620

640

660

680

700

0 100 200 300 400 500 6003,40

3,45

3,50

3,55

3,60

Ileak [nA]

Rpoly [M]

Ccquasi [pF]

ST Sensor 39218

Cint [pF]

IV and CV on Ham. TS

0 50 100 150 200 250

0

1x1019

2x1019

3x1019

4x1019

5x1019

6x10190 100 200 300 400 500

0

10

20

30

40

50Hamamatsu TS - MinisensorIV and CV before Irradiation H35

H36 H37 H38 H39 H40 H41

Cap

acita

nce-2

Bias Voltage [V]

Leak

age

Cur

rent

[nA

]

Strip Parameters on Ham. TS

0 20 40 60 80 100 120 140

0,01

0,1

1

10

0 20 40 60 80 100 120 140

1,6

1,8

2,0

2,2

2,4

0 20 40 60 80 100 120 14050

60

70

80

90

100

110

120

0 20 40 60 80 100 120 1401,4

1,5

1,6

1,7

1,8

Hamamatsu Teststructures - Minisensorbefore Irradiation

H35 H36 H37 H38 H39 H40 H41

Le

aka

ge

Cu

rre

nt [

nA

]

Bia

s R

esi

sta

nce

[M]

Co

up

ling

Ca

pa

cita

nce

[pF

]

Inte

rstr

ip C

ap

aci

tan

ce [p

F]

Comparison: Diode vs. Minisensor

0 50 100 150 200 250 300

0,0

5,0x1019

1,0x1020

1,5x1020

2,0x1020

2,5x1020

3,0x1020

CV on TS H39 - Diode and Minisensor

Diode Minisensor

Ca

pa

cita

nce

-2

Bias Voltage [V]

High fluence (2.5x10^14 neq/cm2)

• FS Ham.@ 1V (AC & bias)

• TS H39 @ 1V

• TS H38 @ 12V

• TS H37 @ 100V

• TS H35 & H36 @ 0V

• TS H40 @ 100V (only bias)

FullSensor Ham.

Teststruc. 37, 38, 39

Teststruc. 35, 36, 40

Ni foil

Proton beam

33MeV

Low fluence (1,5x10^14 neq/cm2)

• FS ST @ 1V• TS ST26 @ 1V• TS H41 @ 0V

FS ST

TS H41, ST26

Ni foil

Proton beam

Fluence estimate (preliminary)

• Leakage current on TS H39 diode at -8±1°C:I(-8°C) = 5 A

• Leakage current at 20°C (I(T)=I0*T1.5 *e-1.2eV/kT):I(20°C)= (860 ± 190)A

• Volume of diode is 72 mm3

=> I(20°C)/V = (11.9 ± 2.6)mA/cm3

=> Fluence is about (3.0±0.6)e14 neq/cm2

(=4e-17A/cm)

• Leakage current on TS H41I(-9°C) = 1.5 A

• Fluence is about (1.1±0.3)e14 neq/cm2

Hamamatsu:

ST:

Leakage Current on Ham. Diode after Irrad. with high Fluence

0 200 400 600 800 1000

0,0

1,0x10-6

2,0x10-6

3,0x10-6

4,0x10-6

5,0x10-6

6,0x10-6

7,0x10-6

0 200 400 600 800 10001E-11

1E-10

1E-9

1E-8

1E-7

1E-6

1E-5

Irradiated, annealed, -8°C Non irradiated, RT

Hamamatsu TS 39 - Diode

Le

aka

ge

Cu

rre

nt [

A]

Voltage [V]

Leakage Current on Ham. Diode after Irradiation with low Fluence

0 200 400 600 800 1000

0,0

0,5

1,0

1,5

2,0

2,5

Hamamatsu TS 41 - Diode

Before After irrad. (low fluence) and annealing

Le

aka

ge

Cu

rre

nt [A

]

Bias Voltage [V]

CV on Ham. Diode after Irradiation

0 200 400 600 800 10001,5x1020

2,0x1020

2,5x1020

3,0x1020

Hamamatsu TS 39 - Diode

Before After IrradiationC

ap

aci

tan

ce-2

Bias Voltage [V]

CV on Sensors after Irradiation

0 200 400 600 800 1000 1200

0,00

0,05

0,10

0,15

0,20

0,25

0,30

0,35

CV(1kHz) on both Sensors at -10°C

Ham. Ham. irrad. (high fluence) ST ST irrad. (low fluence)

1/C

2

Bias Voltage [V]

IV for Sensors after Irradiation

0 200 400 600 800 1000 1200

0,0

0,5

1,0

1,5

2,0IV after Irradiation

Hamamatsu -12°C (high fluence) ST -10°C (low fluence)

Le

aka

ge

Cu

rre

nt [

mA

]

Bias Voltage [V]

Coupling Capacitance on ST Sensor after Irradiation

0 100 200 300 400 500 600300

400

500

600

700

800 ST Sensor

Before After Irradiation (-10°C)

Co

up

ling

Ca

pa

cita

nce

[p

F]

Poly Resistance on ST Sensor after Irradiation

0 100 200 3001,0

1,5

2,0

2,5

3,0 ST Sensor

Before After Irradiation (-10°C)

Po

ly R

esi

sta

nce

[M]

Leakage Current ST FS after irrad.

1-4nA before irrad.

Other Paramters on ST Sensor

• Interstrip Capacitance (one neighbour):Before Irradiation 3.5 pFAfter Irradiation 3.6 pF

• Interstrip Resistance:Before Irradiation > 10G– No definite numbers after irrad

Strip Leakage Current on Ham. Sensor after Irradiation

0 50 100 150 200 2500,1

1

10

100

1000

10000 Hamamatsu FS 39

Before After irradiation

Str

ip L

ea

kag

e C

urr

en

t [n

A]

Poly Resistance on Ham. Sensor after Irradiation

60 80 100 120 140 160 180 200 220 240 260 280 3001,0

1,5

2,0

2,5

3,0 Hamamatsu Sensor 39

Before After Irradiation (-10°)

Po

ly R

esi

sta

nce

[M]

300V, -13°C 160V

Interstrip Capacitance (one neighbour) vs. Bias Voltage

after Irradiation

0 200 400 600 800 1000

3,5

4,0

4,5

5,0

5,5

6,0Hamamatsu FS - C

int on strip 335

Cin

t [p

F]

Bias Voltage [V]

Strip Leakage Current on TS after Irradiation

0 20 40 60 80 100 120 1400,01

0,10

1,00

10,00

100,00

1000,00

10000,00Strip Leakage Current on TS H39

Before After irrad. and annealing

Str

ip L

ea

kag

e C

urr

en

t [n

A]

Coupling Capacitance on TS after Irradiation

0 20 40 60 80 100 120 140

20

40

60

80

100

120

Coupling Capacitance on TS H39

Before After irrad. and annealing

Co

ulp

ling

Ca

pa

cita

nce

[pF

]

Poly Resistance on TS after Irradiation

0 20 40 60 80 100 120 1401,0

1,5

2,0

2,5

3,0 Hamamatsu TS 41 - Minisensor

Before After Irradiation (-10°C)

Po

ly R

esi

sta

nce

[M]

Interstrip Capacitance on TS after Irradiation (2 neighbours)

0 10 20 30 40 50 60

1,0

1,2

1,4

1,6

1,8

2,0

Interstrip Capacitance on TS H39

Before After irrad. and annealing

Inte

rstr

ip C

ap

aci

tan

ce [p

F]

Some bad contacts due to residuals of conductive rubber!?!?!

Interstrip Resistance on TS after Irradiation (very preliminary)

0 10 20 30 40 50 60

-0,2

0,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

Interstrip Resistance on TS H39

Before irradiation >10G

After irrad. and annealing

Inte

rstr

ip R

esi

sta

nce

[G]

Depletion Voltage and Fluence

0 50 100 150 200 250 300

0,0

2,0x1019

4,0x1019

6,0x1019

8,0x1019

1,0x10200 50 100 150 200 250 300

0,0

2,0x1019

4,0x1019

6,0x1019

8,0x1019

1,0x10200 50 100 150 200 250 300

0

1x1017

2x1017

3x1017

4x1017

5x1017

150V

No Fluence

Bias Voltage [V]

CV on Ham. TS - Minisensor

180V

Low Fluence

Ca

pa

cita

nce

-2

220V

High Fluence

Conclusion: Procedure for the production

• Evaluation on minisensor and FS only

• Irradiation with protons is feasible with small bias voltage near to final LHC condition

• We have to evaluate the irrad. sensor with higher Vbias

• The IQC in Karlsuhe is ready with some possible improvements, learned at this system test level

• Some additonal measurments and x-ray studies are ongoing and helpfull for the surface damage understanding but are not

essential for the approval of an ingot!

End of irradiation

„I-t“

Backside of HPK sensor

First GCD measurements

CMS-GCD-StructuresDiodeGateDiodeDiode

GateDiodeDiodeDiode

Measurement of the CMS square GCD structure and Rose

structure in literatureHamamatsu No.00045

1,00E-11

1,50E-11

2,00E-11

2,50E-11

3,00E-11

3,50E-11

4,00E-11

4,50E-11

5,00E-11

5,50E-11

6,00E-11

-35,00 -30,00 -25,00 -20,00 -15,00 -10,00 -5,00 0,00

Gate Voltage (V)

Bia

s C

urr

en

t (A

) 1 V

6 V

11 V

16 V

21 V

Bias Voltage

Some non-understood points.

KA

Rose

GCD after proton irradiationHamamatsu No.00045 irradiated and annealed

1,00E-11

1,00E-07

2,00E-07

3,00E-07

4,00E-07

5,00E-07

6,00E-07

7,00E-07

8,00E-07

9,00E-07

-3,50E+01 -2,50E+01 -1,50E+01 -5,00E+00 5,00E+00 1,50E+01 2,50E+01 3,50E+01 4,50E+01 5,50E+01 6,50E+01

Gate Voltage (V)

Bia

s C

urr

en

t (A

) 1 V

6 V

11 V

16 V

21 V

Bias Voltage

GCD Summary

• Proton irradiation has shown that bulk leakage current is much higher than interface currents at least at full dose and is therefore negligible. (see

also NIM A444 (2000) 605-613) What about effects of type inversion?

• However further studies at Karlsruhe are possible by using the KA X-Ray source.

Bias contacts