rd50 rd50 workshop freiburgkatharina kaska 1 determination of depletion voltage from cv, iv and cce...

RD50 workshop Freiburg Katharina Kaska 1

RD50

Determination of depletion voltage from CV, IV and CCE measurements on Pad Detectors

Katharina Kaska, Michael Moll

CERN-PH


RD50 Introduction

Various methods to determine the depletion voltage

• Standard CV• IV• CCE vs. voltage:

- from TCT with laser

- with source (not via scope): β-source

Do they agree?


RD50 Material

MCz– HIP-MCz-01-n 0.5 x 0.5 cm2 Vfd ~320V (ρ ~ 1 kΩcm) n-type

– 8556-3 (CiS) 0.5 x 0.5 cm2 Vfd ~100V (ρ ~ 2.9 kΩcm) n-type

– HIP-003-C 0.25 x 0.25 cm2 Vfd ~300V (ρ ~ 1 kΩcm) n-type

– p069/8 0.5 x 0.5 cm2 Vfd ~115V (ρ ~ 7.4 kΩcm) p-type

Epitaxial (150 µm)– HIP-004-C 0.25 x 0.25 cm2 Vfd ~150V (ρ ~ 500 Ωcm) n-type

– CNM-11 0.5 x 0.5 cm2 Vfd ~155V (ρ ~ 500 Ωcm) n-type

– CNM-22 0.5 x 0.5 cm2 Vfd ~210V (ρ ~ 980 Ωcm) p-type

Float Zone– CNM-03 0.5 x 0.5 cm2 Vfd ~20V (ρ ~ 15 kΩcm) n-type

– HIP-002-C 0.25 x 0.25 cm2 Vfd ~20V (ρ ~ 15 Ωcm) n-type

– CNM-20 0.5 x 0.5 cm2 Vfd ~2V (ρ ~ 470 kΩcm) p-type


RD50 Material II

0.0 3.0x1014 6.0x1014 9.0x1014 1.2x1015 1.5x10150

100

200

300

400

500

600

dep

leti

on

vo

tag

e [V

]

proton fluence [cm-2]

HIP-003 (2.5 x 2.5 mm2)

HIP-001 (5 x 5 mm2)

depletion voltage from CV

For a part of the CCE measurements diodes of smaller size were used.No differences were observed in comparing results obtained on small (2.5x2.5) and big (5x5mm2) diodes (except for the noise levels in CCE).

Example:

MCz-n


RD50 Experimental procedure

• Irradiation– 24 GeV/c protons at CERN at 27C– 1 MeV neutrons in Ljubljana

• Annealing– 4 minutes at 80C

• CV/IV– Measured at room temperature in parallel mode at 10kHz

• CCE– NIKHEF setup

• TCT– IR laser


RD50 TCT setup

• all detectors were measured at -5±0.1C• humidity in the box was around 15%

- voltage applied with Cu/Be needle - floating guard ring!!!

- N2 atmosphere- Peltier cooling

- 660nm red laser - 1060nm IR laser


RD50 CCE setup

P Mscin tilla to r

d iode

co llim ator

90S r sou rce

NIKHEF setup by Fred Hartjes

signal shaping time: 2.5 µs

guard ring connected to ground

• all detectors were measured at -20±1C• humidity in the box was 18-30%

• gain of 247 e-/mV for these conditions


RD50 IR laser vs. beta

0 50 100 150 200 250 300

0

20

40

60

80

arb

itra

ry u

nit

s

bias voltage [V]

CCE TCT IR

CNM-03-F-43 1.66 x 1014 p/cm2

0 100 200 300 400 500 600

0

10

20

30

40

50

60

70

80

90

100

arb

itra

ry u

nit

s

bias voltage [V]

CCE TCT IR

HIP-003-C55 4.43 x 1014 p/cm2

BUT: only very few samples investigated!

Fz-nMCz-n

IR laser goes through sample (red laser only on surface) => similar to β particles

!!! Only for curve shape comparison, not CCE values!!!


RD50 Fz n-type

0 1x1014 2x1014 3x1014 4x1014 5x1014 6x10140

50

100

150

200

250

300

350

400

de

ple

tio

n v

olt

ag

e [V

]

proton fluence [cm2]

CV IV CCE

CNM-03 (Fz n-type)

IV < CV < CCE (β)

100 200 300 400 500 600 70020

30

40

50

60

70

80

arb

itra

ry u

nit

s

bias voltage [V]

1/C CCE

CNM-03-F-56 4.43 x 1014 p/cm2

24 GeV/c proton irradiated


RD50 Fz n-type

1 MeV neutron irradiated

0 1x1014 2x1014 3x1014

0

100

200

300

400

500

600

CV IV CCE

dep

leti

on

vo

ltag

e [V

]

neutron fluence [cm-2]

CNM-03 Fz-n neutron irradiated

IV < CV < CCE (β) =>same as proton

100 200 300 400 500 600 70010

20

30

40

5060708090

100

arb

itra

ry u

nit

s

bias voltage [V]

1/C CCE

CNM-03-F-91 3x1014 n/cm2


RD50 Fz p-type

0 1x1014 2x1014 3x1014 4x1014 5x1014

0

50

100

150

200

250

300

dep

leti

on

vo

ltag

e [V

]

proton fluence[cm-2]

CV IV CCE

CNM-20-F Fz-p

10 100

20

40

60

80

arb

itra

ry u

nit

s

voltage [V]

1/C I CCE

CNM-20-F-57 4.43 x 1014 p/cm2

1013 101410-6

10-5

10-4

I at d

eple

tion

[A]


CNM-03-F Fz-p

Not linear at high fluences

IV < CV < CCE (β)



RD50 MCz n-type

0.0 2.0x1014 4.0x1014 6.0x1014 8.0x1014 1.0x10150

50

100

150

200

250

300

CV IV CCEd

eple

tio

n v

olt

age

[V])


HIP-003 (MCz n-type)

IV < CCE (beta) < CV => different from Fz


100 200 300 400 500

20

40

60

80

arb

itra

ry u

nit

s

bias voltage [V]

CCE 1/C

HIP-003-C33 8.21 x 1014 p/cm2


RD50 MCz p-type

50 100 150 200 250 300 35040010

20

30

40

50

60

70

arb

itra

ry u

nit

s

bias voltage [V]

CV CCE

p069-44 5.42 x 1014 p/cm2

0.0 2.0x1014 4.0x1014 6.0x1014 8.0x1014 1.0x10150

50

100

150

200

dep

leti

on

vo

ltag

e [V

]


CV IV CCE

p-069 (MCz p-type)

IV < CCE (beta) = CV



RD50 EPI n-type

0.0 2.0x1014 4.0x1014 6.0x1014 8.0x1014 1.0x10150

50

100

150

200

dep

leti

on

vo

ltag

e [V

]


CV IV CCE

HIP-004-C (EPI n-type)

50 100 150 200 250 30010

15

20

25

30

35

40

1/C CCE

arb

itra

ry u

nit

s [V

]

voltage [V]

HIP-004-C21 8.21 x 1014 p/cm2

IV < CCE (β) < CV => same as MCz



RD50 EPI n-type

0.0 3.0x1014 6.0x1014 9.0x1014 1.2x10150

50

100

150

200

250

dep

leti

on

vo

ltag

e [V

]

neutron fluence [cm-2]

CV IV CCE

HIP-004-C (EPI-n) neutron

IV < CV < CCE (β) => different from proton irrad.


100 200 300 400 500

HIP-004-C05 (n-type) 1x1015 n/cm2

arb

itra

ry u

nit

sbias voltage [V]

CCE 1/C (normalised over Vd) I (normalised over Vd)


RD50 EPI p-type

0.0 2.0x1014 4.0x1014 6.0x1014 8.0x1014

0

50

100

150

200

dep

leti

on

vo

ltag

e [V

]


CV IV CCE

CNM-22-E (EPI p-type)

10 100

20

40

60

80

100

arb

itra

ry u

nit

s

bias voltage [V]

1/C CCE

CNM-22-E-15 4.43 x 1014 p/cm2

IV < CV < CCE (β)



RD50 EPI p-type

IV < CV < CCE (β)

100 100010

15

20

25

30

35

40

CNM-22-E-26 1x 1015 n/cm2

arb

itra

ry u

nit

s

bias voltage [V]

1/C CCE



RD50 Overview

material Irradiation Highest values Junction

Fz-n proton CCE back

Fz-n neutron CCE back

Fz-p proton CCE front

MCz-n proton CV ?

MCz-p proton CV=CCE ?

EPI-n proton CV front

EPI-n neutron CCE back

EPI-p proton CCE back

EPI-p neutron CCE front

There seems to be no correlation with:• material• n- or p-type• side of junction


RD50 Summery and outlook

Summery• Depletion voltages from CV, IV and CCE were investigated for Fz, MCz and EPI

material.• All methods on their own show expected behaviour, but don’t agree in values.• No clear correlations with inversion, material and type.

Outlook:• Look at rest of methods

• Investigate after annealing (change in curve shape)

Thanks!


RD50

• spares


RD50 Fz n-type

0.0 2.0x1014 4.0x1014 6.0x1014 8.0x10140

100

200

300

400

500

dep

leti

on

vo

ltag

e [V

]


CV red laser

CNM-03 Fz-n

100 200 300 400 50010

20

30

40

50

60

7080

arb

itra

ry u

nit

s

bias voltage [V]

1/C red laser (front)

CNM-03-F-56 4.43e14p

0 1x1014 2x1014 3x1014 4x1014 5x10140

50

100

150

200

250

300

350

400

dep

leti

on

vo

ltag

e [V

]


CV red laser TCT

(front=electron signal) CCE

CNM-03 Fz-n


CV < red laser = CCE (β)

TCT with red laser from the front:electron signal in n-type


RD50 MCz n-type

100 1000

0.2

0.4

0.6

0.8

1

arb

itrar

y un

its

voltage [V]

CV red laser TCT

HIP-MCz-01-n-23 9.7 x 1014 p/cm2

0.0 3.0x1014 6.0x1014 9.0x1014 1.2x1015 1.5x1015100

200

300

400

500

600

dep

leti

on

vo

ltag

e [V

]


CV red laser TCT

front=electron signal CCE

HIP-MCz-01 MCz-n


red laser = CCE (β) < CV

TCT with red laser from the front:electron signal in n-type


RD50 MCz p-type

100

20

40

60

80

arb

itra

ry u

nit

s

bias voltage [V]

p069-44 MCz-p 5.42 x 14 p/cm2

0.0 3.0x1014 6.0x1014 9.0x1014 1.2x1015 1.5x10150

100

200

300

400

500

Vfd

[V

]


CV red laser TCT

(back = electron signal) CCE

Depletion voltage comparison MCz-p

red laser < CCE (β) = CV

TCT with red laser from the back:electron signal in p-type



RD50 Front vs. back

HIP-MCz-01-n-261.08x1014 neq cm-2

proton

Junction is on front.

0 100 200 300 400 500 600-10

0

10

20

30

40

50

60

70

80

90

100

CC

E D

AQ

bias voltage [V]

TCT red front TCT red back TCT IR

HIP-003-C53 1.66e14 p

Front signal: electronsBack signal: holes


RD50 Back vs. front

p069-443.35x1014 neq cm-2

proton

front (holes) back (electrons)

0 100 200 300 400 500

0

10

20

30

40

50

60

70

80

CC

E D

AQ

bias voltage [V]

TCT red front TCT red back TCT IR

p069-44 5.42e14 p

Front signal: holesBack signal: electrons

MCz-p


RD50 Protons vs. neutrons

0 50 100 150 200 250 300

0

10

20

30

40

50

60

70

80

90

100

CNM-11-E-91 (1 x 1015 n/cm2)

arb

itra

try

un

its

bias voltage [V]

normalised curves TCT red TCT IR

0 50 100 150 200 250 300

0

10

20

30

40

50

60

70

80

90

100

CNM-22-E-25 3 x 1014 n/cm2

arb

itra

try

un

its

bias voltage [V]


0 50 100 150 200 250 300

0

10

20

30

40

50

60

70

80

90

100

CC

E D

AQ

bias voltage [V]


CNM-22-E-15 4.43 x 1014 p/cm2

0 50 100 150 200 2500

10

20

30

40

CC

E D

AQ

bias voltage [V]

TCT red TCT IR

HIP-004-C26 4.43e14 p

p-in-n diode (inverted)

Not invertedn-in-p diode (not inverted)

inverted

proton neutronHigh fluences

rd50 rd50 workshop freiburgkatharina kaska 1 determination of depletion voltage from cv, iv and cce...

Documents