CMS HPK Sensor Characterization - Vertex 2012vertex2012.knu.ac.kr/slide/s3/CMS HPK Sensor Characterization.pdf · Wafer materials (total 164 wafers): Float-zone 320µm, 200µm, 200µm

KIT – University of the State of Baden-Wuerttemberg and

National Research Center of the Helmholtz Association

INSTITUT FÜR EXPERIMENTELLE KERNPHYSIK

www.kit.edu

CMS HPK Sensor Characterization

A. Dierlamm on behalf of the CMS Tracker Collaboration

A. Dierlamm

Institut für Experimentelle Kernphysik

2 17.09.2012 VERTEX 2012, Jeju, Korea

Outline

Sensor Requirements

HPK Campaign Intro

Mini strip sensors

IV, CV compared to diodes

Strip parameters

Charge collection

Cluster widths

Multi-geometry strip sensors

Strip capacitance study

Lorentz shifts

New sensor design: Fourfold segmented strip sensor with edge read-

out

A. Dierlamm



Requirements for Silicon Strip Sensors – I

Very high radiation hardness for up to 1.5e15neq/cm²

need well detectable signal possibly at ≤ 600V

need to study mixed irradiation fields as in the experiment, since oxygenated silicon material does show NIEL violation and we need to quantify the benefits

need to consider binary read-out

CMS Binary Chip might be operated at a threshold of around 1fC (~6240e-)

different cluster definition and resolution than analogue

0 10 20 30 40 50 60 70 80 90 100 11010

13

1014

1015

1016

1017

Flu

ence

(1/c

m²)

Radius (cm)

Z=0cm (barrel):

Charged hadrons

Neutral hadrons

Total

Z=250cm (end-cap):

Charged hadrons

Neutral hadrons

Total

3000fb-1

http://www.hep.ph.ic.ac.uk/~dmray/CBC_doc

umentation/CBC_status_Oct_2011.pdf

NIM A 623 (2010) 177–179

n-in-p FZ

A. Dierlamm



Requirements for Silicon Strip Sensors – II

Increased granularity to cope with higher track density

(PU ~100 or even ~200)

shorter strips, not necessarily smaller pitch (80µm – 100µm sufficient)

outer regions ~ 5cm long strips (currently 20cm)

inner region down to ~1mm to separate interactions (needed for contribution to L1

trigger)

optional: increased complexity of routing lines

integrated PA to reduce glass substrates

routing of inner strips to edge on sensors with four-fold segmentation

High PU event picture integrated PA

Fourfold segmented

strip sensor with

edge read-out

A. Dierlamm



Sensors

200µm

Fram

e (hyb

rids)

Hybrid

s

Fram

e (senso

rs)

Opto

Alu c

ontact

s

Power

Cooling

ASICs

Connector

Screws

HV

0

1

2

3

4

5

6

7

8

9

10

11

We

igh

t (g

)

0.0

0.1

0.2

0.3

0.4

0.5

X/X

0 (

%)

Requirements for Silicon Strip Sensors – III

Reduced material

material budget for new module concept is dominated by silicon weight

thinner sensors 200µm, 150µm?

also beneficial to reduce bias voltage and leakage current

but: less signal, brittle, more expensive

integrated PA to replace glass substrates

Total module mass: 29.0g

(320µm: 34.4g)

Total X/X0: 1.06%

(320µm: 1.33%)

2S module

Numbers from D. Abbaneo

A. Dierlamm



Purpose of measurement campaign

Investigate limits of radiation tolerance for various available silicon bulk materials for thicknesses ≤320µm

get information after pure proton and neutron irradiations as well as after mixed irradiations corresponding to expected mixture

Investigate performance and functionality of new sensor designs

Provide the Tracker Simulation Group with detailed information about: parameters like strip capacitance, collected charge, cluster width, resolution, Lorentz shift, leakage current

dependence on sensor design, material, bias voltage, irradiation fluence, annealing, temperature,…

Choice of sensor material and design is driven by the overall performance of the tracker and therefore also depends on the new module concept and read-out chip

To get consistent results we use wafers produced by one company with same process steps

irradiate samples for a given fluence together where possible

use one protocol to perform the measurements at several institutes

perform cross-calibrations of the participating institutes

A. Dierlamm



HPK Campaign

Wafer materials (total 164 wafers):

Float-zone

320µm, 200µm,

200µm deep diff.*, 120µm deep diff.*,

120µm on carrier,

200µm deep diff.* with 2. metal layer

Magnetic Czochralski

200µm

Epitaxial silicon

100µm, 70µm, 50µm

all as n-type and p-type

(with p-stop and p-spray strip isolation)

Characterizations are done before and after

irradiations (both with 23MeV protons @ KIT and

reactor neutrons @ JSI, Ljubljana)

* 320µm physical thickness; active thickness reduced by deep in-diffusion of back-side doping

Radius Protons Neutrons Ratio p/n Total Material

40cm 3 4 0.75 7.0 ≥ 200µm

20cm 10 5 2.00 15.0 ≥ 200µm

15cm 15 6 2.50 21.0 ≥ 200µm

10cm 30 7 4.29 37.0 ≤ 200µm

5cm 130 10 13.00 140.0 < 200µm

Chosen irradiation fluences in 1e14neq/cm²

A. Dierlamm



Caveat

The campaign is not completed yet! The highest irradiation and an additional set of GeV proton irradiations was performed, but not all samples are characterized yet

Final analyses and simulations ongoing

There are plenty of measurements on a multitude of structures, which cannot be summarized in the given time frame

I concentrate on measurements obtained from strip sensors mainly done at KIT

In addition, we perform beam tests and the analysis will be presented at RESMDD12 in Florence

investigate dedicated test-structures designed for fast evaluation of process quality of large-scale productions (will also be presented at RESMDD12)

investigate trapping effects and the electric fields with TCT and edge-TCT

perform simulation studies to understand and predict the device performance

investigate various designs of pixel and short strip sensors for inner tracker regions

64 strips,

80µm pitch,

2.6cm long

256 strips,

80µm pitch,

3.3cm long

A. Dierlamm



0.0 5.0x1014

1.0x1015

1.5x1015

0.00

0.02

0.04

0.06

0.08

0.10

0.12

FZ320N

FZ320P

FZ200N

FZ200P

MCZ200N

MCZ200P

Expectation

Sca

led

Vo

lum

e C

urr

en

t a

t R

T (

A/c

m3)

Fluence(neq

/cm2)

Diodes @ 1.2xVfd and -20°C

Leakage Currents - Diodes

Volume generated leakage current

of diodes well within expectations

1011 1012 1013 1014 1015

eq [cm-2]

10-6

10-5

10-4

10-3

10-2

10-1

I

/ V

[

A/c

m3]

n-type FZ - 7 to 25 Kcm

n-type FZ - 7 Kcm

n-type FZ - 4 Kcm

n-type FZ - 3 Kcm

n-type FZ - 780 cm

n-type FZ - 410 cm

n-type FZ - 130 cm

n-type FZ - 110 cm

n-type CZ - 140 cm

p-type EPI - 2 and 4 Kcm

p-type EPI - 380 cm

[M.Moll PhD Thesis][M.Moll PhD Thesis]

protons

neutrons

T scaling: ~ T²exp(-1.21eV/(2kBT)

A. Dierlamm



Leakage Currents – Strip Sensors

0 200 400 600 800 1000

0

100µ

200µ

300µ

Cu

rre

nt (A

)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

Strip Sensors @ -20°C

F=1e15neq

/cm² (protons)

IV curve does not show a nice plateau after Vfd

Chose 600V for comparison, which is the max. voltage of current CMS

Tracker PS

Leakage currents tend to be higher for 200µm sensors (up to ~40%)

Absolute temperature measurement is difficult and leads to large errors

protons

neutrons

mixed

A. Dierlamm



Strip Sensors – CV and Full Depletion Voltages

Vfd vs. F increases faster for thick

and for p-type sensors

Points at 7e14neq/cm² are taken

after mixed irradiation (3e14neq/cm²

protons and 4e14neq/cm² neutrons

plus additional annealing of

~19min@60°C)

We see a kind of saturation for

F>5e14neq/cm²

0 100 200 300 400 500

0.0

5.0x1018

1.0x1019

1.5x1019

2.0x1019

F=0neq

/cm²

T=+20°C

f=1000Hz

1/C

^2

(F

-2)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

0 200 400 600 800 1000

0.0

5.0x1018

1.0x1019

1.5x1019

2.0x1019

1/C

^2

(F

-2)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=5e14neq

/cm² (n)

T=-20°C

f=1000Hz

0 200 400 600 800 1000

0.0

5.0x1018

1.0x1019

1.5x1019

2.0x1019

F=10e14neq

/cm² (p)

T=-20°C

f=1000Hz

1/C

^2

(F

-2)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

0 1 2 3 4 5 6 7 8 9 100

100

200

300

400

500

600

700

800

900

1200

Fu

ll D

ep

letio

n V

olta

ge

(V

)

Fluence (1e14neq

/cm²)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

above 1000V

protons

neutrons

mixed&annealing

A. Dierlamm



Neff Comparison – Strip Sensors vs. Diodes

Although the determination of full depletion voltage after irradiation is not very

accurate, the results from strip sensors and diodes of same materials show good

agreement.

0 1 2 3 4 5 6 7 8 9 100.0

5.0x1012

1.0x1013

1.5x1013

2.0x1013

2.5x1013

3.0x1013

|Ne

ff|(

cm

-3)

Fluence (1e14neq

/cm²)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

0 1 2 3 4 5 6 7 8 9 100.0

5.0x1012

1.0x1013

1.5x1013

2.0x1013

2.5x1013

3.0x1013

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

|Ne

ff|(

cm

-3)

Fluence (1e14neq

/cm²)

protons

neutrons

mixed&annealing

Strip Sensors Diodes

A. Dierlamm



Strip Parameters vs. Fluence – I

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1625.0p

26.0p

27.0p

28.0p

29.0p

30.0p

protons

neutrons

mixed

Co

up

ling

Ca

pa

cita

nce

(F

/cm

)

Fluence (1e14neq

/cm²)

FZ320N FZ200N MCZ200N

FZ320P FZ200P MCZ200P

FZ320Y FZ200Y MCZ200Y

Vbias

= 600V

T = -20°C

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

600.0k

800.0k

1.0M

1.2M

1.4M

1.6M

1.8M

2.0M

2.2M

2.4M

2.6M

2.8M

3.0M

3.2M

3.4M

Vbias

= 600V

T = -20°C

Bia

s r

esis

tan

ce

(

)

Fluence (1e14neq

/cm²)




protons

neutrons

mixed

Hardly any change of coupling capacitance

(~4% variations)

Decrease of inter-strip resistance

p-spray isolation (FZ320Y) still shows

about 50Mcm at 3.8e15neq/cm² !

saturation value?

Increase of bias resistance by 15-25%

independent of particle type (p/n)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 36 37 38 39

100k

1M

10M

100M

1G

10G

100G

1T

10T

Vbias

= 600V

T = -20°C

FZ320Y Badd

Inte

r-str

ip R

esis

tan

ce

(

cm

)

Fluence (1e14neq

/cm²)




protons

neutrons

mixed

A. Dierlamm



Strip Parameters vs. Fluence – II

Minor changes in inter-strip capacitance

Back capacitance quite different for p- and n-type due to difference in CV curve

results in ~7.5% higher strip capacitance for p-type sensors at F≥1e15neq/cm² at moderate bias voltage (600V)

Strip capacitance increases about 5% after 3e14neq/cm² and stays at that level

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 36 37 38 39

380f

400f

420f

440f

460f

480f

500f

520f

Vbias

= 600V

T = -20°C

protons

neutrons

mixed

FZ320Y Badd

Inte

r-str

ip C

ap

acita

nce

(F

/cm

)

Fluence (1e14neq

/cm²)




0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

150f

200f

250f

300f

350f

400f

450f

500f

550fprotons

neutrons

mixed

Vbias

= 600V

T = -20°C

Str

ip B

ack C

ap

acita

nce

(F

/cm

)

Fluence (1e14neq

/cm²)

FZ320N FZ200N

FZ320P FZ200P

FZ320Y FZ200Y

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 161.10p

1.15p

1.20p

1.25p

1.30p

1.35p

1.40p

1.45p

1.50p

1.55p

1.60p

protons

neutrons

mixed

Vbias

= 600V (900V)

T = -20°C

To

tal S

trip

Ca

pa

cita

nce

(F

/cm

)

Fluence (1e14neq

/cm²)

FZ320N FZ200N

FZ320P FZ200P

FZ320Y FZ200Y

A. Dierlamm



Label 1-120 1-240 1-80 1-70 2-120 2-240 2-80 2-70 3-120 3-240 3-80 3-70

Region 1 2 3 4 5 6 7 8 9 10 11 12

Pitch 120 240 80 70 120 240 80 70 120 240 80 70

Width 16(+1) 34(+1) 10(+1) 8.5(+1) 28(+1) 58(+1) 18(+1) 15.5(+1) 40(+1) 82(+1) 26(+1) 22.5(+1)

Width Al 29(-5) 47(-5) 23(-5) 21.5(-5) 41(-5) 71(-5) 31(-5) 28.5(-5) 53(-5) 95(-5) 39(-5) 35.5(-5)

w/p 0.133

(0.142)

0.142

(0.146)

0.125

(0.138)

0.121

(0.136)

0.233

(0.242)

0.242

(0.246)

0.225

(0.238)

0.221

(0.236)

0.333

(0.342)

0.342

(0.346)

0.325

(0.338)

0.321

(0.336)

Multi-geometry Silicon Strip Detector (MSSD)

Measure strip capacitance for various

layouts

Validation of results from 2000 and

extension of measurement range for

thinner sensors

?

1 12

NIM A 466 (2001) 300-307

A. Dierlamm



MSSD – Strip Capacitances at 200µm

Strip capacitance stays constant for given w/p ratio also for 200µm

Large pitch of 240µm:

increased strip

capacitance due to high Cbck

early break down

not considered as

option for CMS Tracker

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.00.0

0.5

1.0

1.5

2.0

p=240µm

p=120µmp=80µm

C_int (pF/cm) C_bck (pF/cm) C_strip (pF/cm)

w/p=0.13 w/p=0.23 w/p=0.33

FZ200N FZ200P FZ200Y

Ca

pa

cita

nce

(p

F/c

m)

p/(d+pf(w/p))

p=70µm

A. Dierlamm



MSSD – Cint Ramp Simulations

Mostly excellent agreement with

measurements on all geometries

Simulations performed with Silvaco ATLAS

and confirmed with Synopsys Sentaurus

p=120µm p=240µm

p=80µm p=70µm

p=120µm p=240µm

p=80µm p=70µm

p=120µm p=240µm

p=80µm p=70µm

A. Dierlamm



MSSD – Strip Capacitance vs. Fluence

Almost no change of strip capacitances

of all geometry variations as observed

for standard mini strip sensors (close to

geometry 2-80) for high bias voltage

0 5 10 151.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

To

tal S

trip

Ca

pa

cita

nce

(p

F/c

m)

Fluence (1e14neq

/cm²)

1-120

1-240

1-80

1-70

2-120

2-240

2-80

2-70

3-120

3-240

3-80

3-70

FZ200N @ 500V

0 5 10 151.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2.0

2.1

2.2

2.3

2.4

2.5

To

tal S

trip

Ca

pa

cita

nce

(p

F/c

m)

Fluence (1e14neq

/cm²)

1-120

1-240

1-80

1-70

2-120

2-240

2-80

2-70

3-120

3-240

3-80

3-70

FZ200P @ 500V

0 5 10 151.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

To

tal S

trip

Ca

pa

cita

nce

(p

F/c

m)

Fluence (1e14neq

/cm²)

1-120

1-240

1-80

1-70

2-120

2-240

2-80

2-70

3-120

3-240

3-80

3-70

FZ200P @ 800V

A. Dierlamm



Charge Collection – Intro

Measurement done with Sr90 source and Beetle

read-out chip with ~20ns shaping time

(ALiBaVa system) on standard mini sensors

Cluster charge with 5σ seed and 2σ neighbor cut

Calibration work is in progress

(chips individually sensitive to T, Cstrip)

We do voltage ramps up to 1000V for

each material and fluence, and at several

annealing steps after mixed irradiation

0 200 400 600 800 1000

4000

6000

8000

10000

12000

14000

16000

18000

20000

22000

24000

26000

Sig

na

l (e

-)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=0eq

/cm²

T=+20°C

Sr90 source

0 200 400 600 800 1000

4000

6000

8000

10000

12000

14000

16000

18000

20000

22000

24000

26000

Sig

na

l (e

-)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=3e14neq

/cm² (p)

T=-20°C

Sr90 source

0 200 400 600 800 1000

4000

6000

8000

10000

12000

14000

16000

18000

20000

22000

24000

26000

Sig

na

l (e

-)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=4e14neq

/cm² (n)

T=-20°C

Sr90 source

0 200 400 600 800 1000

4000

6000

8000

10000

12000

14000

16000

18000

20000

22000

24000

26000

Sig

na

l (e

-)Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=1e15neq

/cm² (p)

T=-20°C

Sr90 source

FZ320N

V = 500V

F = 1e15neq/cm²

FZ320N

V = 500V

F = 0neq/cm²

A. Dierlamm



Charge Collection – Summary

F≤7e14neq/cm² (Tracker radius of ≥40cm)

Thicker material gives more charge

No dominance of p- vs. n-type visible

At 1e15neq/cm²

FZ320N collects least charge in the voltage range of 400V – 600V, but catches up ≥ 700V

FZ materials shows increasing charge from 600V to 900V, MCz does not

collected charge is above 10’000e- for all materials at 600V (current PS limit)

At 1.5e15neq/cm² (Tracker radius of ~20cm)

Only one point at the moment

FZ320P shows signal below 10’000e- at 600V!

0 200 400 600 800 10004000

6000

8000

10000

12000

14000

16000

18000

20000

Sig

na

l (e

-)

Voltage (V)

FZ320N

FZ320P

FZ200N

FZ200P

M200N

M200P

F=1e15neq

/cm² (p)

T=-20°C

Sr90 source

0 2 4 6 8 10 12 14 165000

10000

15000

20000

25000

30000

FZ320N 600V FZ320N 900V

FZ320P 600V FZ320P 900V

FZ200N 600V FZ200N 900V

FZ200P 600V FZ200P 900V

M200N 600V M200N 900V

M200P 600V M200P 900V

co

rr. S

ign

al (e

-)

Fluence (1e14neq

/cm²)

protons

neutrons

mixed

A. Dierlamm



240 480 720 1000 100008000

10000

12000

14000

16000

18000

20000

co

rr. S

ign

al (e

)

eq. annealing time at RT (h)

FZ320N 600V

FZ320P 600V

FZ320N 900V

FZ320P 900V

10.0 20.0 30.0 41.7 416.7

eq. annealing time at RT (days)

Charge Collection – Annealing

About 10 days annealing is beneficial

1-2 months at RT during maintenance/accidents can be tolerated

Longer annealing reduces signal by almost 50% in one year at RT

Mixed irradiation (~40cm):

3e14neq/cm² (p) & 4e14neq/cm² (n)

A. Dierlamm



Cluster width vs. Fluence and Bias Voltage

Cluster widths for perpendicular tracks and seed/neighbors cut of 5/2 s.

The cluster width profiles differ significantly for n- and p-type sensors.

This is important for performance simulations.

How does it look like for binary read-out?

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

Clu

ste

r w

idth

Voltage (V)

FZ320N

Cluster definition: 5/2

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0 Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10


clu

ste

r w

idth

Voltage (V)

FZ200P

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

FZ200N


0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

Clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

FZ320P


0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

M200P


0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

M200N


A. Dierlamm



Binary interpretation

Cluster width is much smaller in binary mode (1.1-1.4 x pitch(80µm))

Cluster width approaches similar values for p- and n-type

6240e- threshold might miss some clusters already at 5e14neq/cm² and perpendicular tracks; CBC could be optimized for lower thresholds since noise is expected to be ~1000e- for 5cm long strips; to be seen…

Larger inclination means larger spread of charge, therefore even more clusters lost (under investigation with cosmic telescope…)

2000 4000 6000 8000 10000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)

Fraction 1-strip clusters



Fraction >3-strip clusters

avg. width

CIE

FZ200N, 600V, F=5e14neq

/cm²

2000 4000 6000 8000 10000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200P, 600V, F=5e14neq

/cm²

<95% clusters

found

<95% clusters

found

A. Dierlamm



Lorentz Shifts – Magnetic field, Bias Voltage

Shift increases almost linearly with magnetic field; small deviations at B>6T

Holes show about half the shift of electrons due to smaller mobility and rH

Shift increases up to full depletion voltage

Shift reduces for high bias voltage and approaches a saturation value

A. Dierlamm



Lorentz Shifts – Irradiation, Annealing

Shift for holes is initially smaller than for electrons and seems to have a maximum around 1e15neq/cm²

there is almost no annealing effect with the tendency to reduce the shift

Shift for electrons is larger, but falls continuously with F

annealing makes the clusters move by ~10µm in 300µm sensors at 4T

long-term annealing reduces the shift further

n-type:

holes

p-type:

electrons

A. Dierlamm



FOSTER – Intro

New design: FOur-fold segmented STrip sensor

with Edge Readout

increase granularity

keep sensor size of ~10cm x 10cm

allow correlation of two sensor planes on

hybrid at the edge

pT module concept,

M. Raymond, TWEPP2008

A. Dierlamm



FOSTER – Laser scan

The initial implementation

showed unexpected

behavior since many hits

in the near region would

have been wrongly

associated to the far

region

There are ~30% wrongly

assigned clusters when

using a Sr90 source in

the near region

This was seen for p- and

n-type sensors

alu

min

ium

alu

min

ium

alu

min

ium

Far region Near region

alu

min

ium

alu

min

ium

A. Dierlamm



FOSTER – Simulation

Device simulations showed that a common p-stop layer below the read-out strip of an n-in-p sensor would shield it from induced charge and reduce the wrong signals significantly

A structure with this layout modification has been produced at ITE Warsaw and first measurements show indications that the concept works (these measurements are subject to a separate publication)

0 10 20 30 40 50 60 70 80 90 100

0,00E+000

1,00E-015

2,00E-015

3,00E-015

4,00E-015

5,00E-015

Nimp

=1e16cm-3

Qox=1e11cm-2

Ch

arg

e [

C]

Position [µm]

Individ. p-stop

Left strip

RO strip

Right strip

Common p-stop

Left strip

RO strip

Right strip

A. Dierlamm



Not So Nice Observations

Very few devices showed sudden rise of leakage current, which could be cured

by storage in dry atmosphere for few days

Similarly on very few devices we observed shifts in break down voltages

Few 200µm thin MCz sensors broke easily by handling

assembly of modules to be exercised with 200µm dummy wafers…

Characteristics of MCz material showed dependence on proton irrad. energy

Therefore we performed an additional irradiation campaign with GeV protons on

diodes and mini strip sensors of FZ and MCz;

the samples will be delivered to the labs soon…

MCz200/280N diodes irrad. with ~3e14neq/cm²;

Udep from CV

A. Dierlamm



Outlook

Within the CMS Tracker Sensor Working Group we are conducting a

comparative measurement campaign to identify suitable strip sensors

for the next CMS Tracker

We are about to complete the necessary irradiation steps and

measurements to be able to provide information about performance

and features of the various options

Together with the CMS Tracker Simulation Group we will concentrate

on optimizing the tracker performance taking into account the CMS

read-out chip, L1 trigger options and material budget (not to forget

costs and handling)

The CMS Tracker Upgrade group will decide on the silicon material by

beginning of 2013

A. Dierlamm



Thank you for your attention and thanks to the participating institutes

for their contributions

Irradiations funded by:

HPK Campaign

A. Dierlamm



BACKUP

A. Dierlamm



Deep diffusion profiles

FZ320P

FZ200P deep diff.

FZ120P deep diff.

~

A. Dierlamm



Karlsruhe Proton Cyclotron

E ~ 23MeV

Inominal = 1.7µA

T < 0°C

Rbeam ~ 3mm

Beam line with target box Control room

Target box Autoradiography image

of irradiation area Typical beam profile

A. Dierlamm



Ljubljana Reactor – I

A. Dierlamm



Ljubljana Reactor – II

A. Dierlamm



Charge Collection

0 200 400 600 800 1000

5000

10000

15000

20000

FZ200P

Sig

na

l (e

-)

Voltage (V)

Fluence in

1e14neq

/cm²

F=0

F=3

F=4

F=5

F=10

F=0

0 200 400 600 800 1000

5000

10000

15000

20000

FZ200N

Sig

na

l (e

-)

Voltage (V)

Fluence in

1e14neq

/cm²

F=0

F=3

F=4

F=5

F=7

F=10

0 200 400 600 800 1000

5000

10000

15000

20000

25000

30000

FZ320P

Sig

na

l (e

-)

Voltage (V)

Fluence in

1e14neq

/cm²

F=0

F=3

F=4

F=5

F=7

F=10

0 200 400 600 800 1000

5000

10000

15000

20000

25000

30000

FZ320N

Sig

na

l (e

-)

Voltage (V)

Fluence in

1e14neq

/cm²

F=0

F=3

F=4

F=5

F=7

F=10

A. Dierlamm



Eta functions for FZ200P and FZ200N @ 500V

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8


/cm²

F=0 F=4 F=7

F=3 F=5 F=10


clu

ste

r w

idth

Voltage (V)

FZ200P

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

FZ200N


FZ200P, 5e14, 500V FZ200N, 5e14, 500V

A. Dierlamm



Eta functions for FZ200P and FZ200N @ 600V

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8


/cm²

F=0 F=4 F=7

F=3 F=5 F=10


clu

ste

r w

idth

Voltage (V)

FZ200P

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

FZ200N


FZ200N, 5e14, 600V FZ200P, 5e14, 600V

A. Dierlamm



Binary interpretation – n-type

Cluster width

much smaller in

binary mode

Stays within 1.1-

1.4 in efficient

threshold range

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8

3.0

clu

ste

r w

idth

Voltage (V)

Fluence in 1e14neq

/cm²

F=0 F=4 F=7

F=3 F=5 F=10

FZ200N


5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200N, 400V, F=5e14neq

/cm²

5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200N, 600V, F=5e14neq

/cm²

5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200N, 900V, F=5e14neq

/cm²

<95% clusters found

A. Dierlamm



Binary interpretation – p-type

Similar cluster

width as in n-

type (1.1-1.3)

0 200 400 600 800 10000.8

1.0

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

2.8


/cm²

F=0 F=4 F=7

F=3 F=5 F=10


clu

ste

r w

idth

Voltage (V)

FZ200P

5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200P, 400V, F=5e14neq

/cm²

5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200P, 600V, F=5e14neq

/cm²

5000 10000 15000 20000

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Threshold (e-)





avg. width

CIE

FZ200P, 900V, F=5e14neq

/cm²

<95% clusters found

A. Dierlamm



Calibration of Beetle chips

1.15 1.20 1.25 1.30 1.35

60

70

80

90

100

112130

30

31

4050

51

5121

31

31

40

51

12

0N

20

0P

20

0N

32

0N

S/D

(e

/µm

)

Cstrip (pF/cm)

n-type

p-type3

20

P

A. Dierlamm



Scaling of Annealing Time

10m

in@

60°C

20m

in@

60°C

20m

in@

60°C

40m

in@

60°C

76m

in@

60°C

15m

in@

80°C

30m

in@

80°C

60m

in@

80°C

0.1

1

10

100

1000

10000

100000

50

129204

358

700

1970

4978

10085

10

30

50

90

166

346

766

1547

0.9

2.7

4.7

8.7

15.9

30.9

60.9

120.9

5.32

4.79

4.47

4.05

3.59

3.16

2.88

2.66

E

qu

iva

len

t cu

rre

nt a

nn

ea

ling

tim

e

21°C in h

60°C in min

80°C in min

1

2

3

4

5

6

7

alp

ha

(1

e-1

7A

/cm

)

A. Dierlamm



FOSTER – Source measurements on FZ320N

ADC

Source above near region:

seed is near-strip

ADC

Source above near region:

seed is far-strip

ADC

Source above far region:

seed is near-strip

ADC

Source above far region:

seed is far-strip

Documents

CMS HPK Sensor Characterization - Vertex 2012vertex2012.knu.ac.kr/slide/s3/CMS HPK Sensor Characterization.pdf · Wafer materials (total 164 wafers): Float-zone 320µm, 200µm, 200µm