Def

ect a

nnea

ling

in 4

H-S

iC

A. C

asta

ldin

i1 , A

. Cav

allin

i1 , L

. Rig

utti1

, F. N

ava2

1 INFM

and

Dip

artim

ento

di F

isic

a, U

nive

rsità

di B

olog

na, B

olog

na, I

T

2 INFN

and

Dip

artim

ento

di F

isic

a, U

nive

rsità

di M

oden

a e

Reg

gio

Em

ilia,

Mod

ena,

IT

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

Det

ectio

n an

d ch

arac

teriz

atio

n of

ele

ctric

ally

act

ive

defe

cts:

•Dee

p Le

vel T

rans

ient

Spe

ctro

scop

y: c

once

ntra

tion,

ene

rgy

leve

l (e

ntha

lpy)

and

cap

ture

cro

ss s

ectio

n of

ele

ctric

ally

act

ive

defe

cts.

•Cap

acita

nce-

Vol

tage

Cha

ract

eriz

atio

n:fre

e ch

arge

car

rier d

istri

butio

n.

•Ele

ctro

n B

eam

Indu

ced

Cur

rent

:sp

atia

l dis

tribu

tion

and

reco

mbi

natio

n st

reng

th o

f ext

ende

d de

fect

s.

Cha

ract

eriz

atio

n of

the

devi

ce:

Cur

rent

-Vol

tage

Cha

ract

eriz

atio

n: b

ehav

ior o

f dar

k cu

rrent

in p

rese

nce

of

defe

cts.

•C

harg

e C

olle

ctio

n E

ffici

ency

:effe

ct o

f the

def

ects

on

sam

ple

perfo

rman

ce a

s a

char

ged

parti

cle

dete

ctor

.

Cha

ract

eriz

atio

n Te

chni

ques

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

App

licat

ions

•Def

ectiv

e S

tate

ana

lyse

sto

pre

dict

trap

ping

effe

cts.

•Spa

tial d

istri

butio

nof

maj

or re

com

bini

ng c

ente

rs.

•Ann

ealin

g an

d re

cove

ryof

free

cha

rge

carr

iers

at l

ow

tem

pera

ture

.

•Irra

diat

ion

effe

cts

(rad

iatio

n ha

rdne

ss).

•Ana

lysi

s of

irra

diat

ion-

indu

ced

com

pens

atio

n ef

fect

s.

•CC

Ean

alys

is a

s a

func

tion

of ir

radi

atio

n an

d an

neal

ing

tem

pera

ture

.

Mat

eria

l

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

n+ , 4H

– S

iC, 3

60 µ

m

subs

trat

e

ND ≅

7 ⋅

1018

cm

-3

10 m

icro

pipe

/cm

2

n+ , buf

fer,

1 µ

m, N

D =

1018

cm

-3

n, 4

H –

SiC

, 30

µ mN

D =

2.2

⋅ 1015

cm

-3

circ

ular

Sch

ottk

y c

onta

ct

Au

(100

0 Å

), Φ

= 2

mm

Ohm

ic c

onta

ct -

Ti/P

t/Au

Si-f

ace

C-f

ace

IRR

AD

IATI

ON

:

8.6

MeV

el

ectr

ons

at

diffe

rent

do

ses/

fluen

ces

Flue

nce

(cm

-2)

Dos

e

9.48

x 1

01440

Mra

d

2.37

x 1

01410

Mra

d

4.74

x 1

0132

Mra

d

•n 4

H-S

iCep

ilaye

r gro

wn

by C

VD

:

N

D=2

.2x1

015cm

-3, 3

0µm

thic

k•A

u S

chot

tky

cont

act,

φ =2

mm

, 100

0Åth

ick

EB

ICm

icro

grap

hs

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

Dis

loca

tions

ap

pear

as

dark

spo

ts o

n th

e su

rface

Dis

loca

tion

dens

ity is

ab

out

105

cm-2

EB

IC c

ontra

st

up to

40%

DLT

S a

naly

sis

–Irr

adia

tion

indu

ced

deep

leve

ls

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

100

200

300

400

500

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

en=4

6.5

s-1

40 M

rad

S6

S5S4

S3S2

S1

S0

as-re

cive

dx1

00

Tem

pera

ture

(K)

∆C/C

Virg

in (X

100

)

40 M

rad

–9.

48 x

1015

e/cm

2

DLT

S a

naly

sis

–Tr

ap p

aram

eter

s

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

Intro

duct

ion

rate

η(c

m-1

)

Cap

ture

cro

ss

sect

ion

σ int

er (c

m2 )

Con

cent

ratio

n

NT

(cm

-3)

Dee

p le

vel e

ntha

lpy

ET

(eV

)

0.09

7.2

x 10

-15

4.6

x 10

13E

c -0

.89

S50.

276.

6 x

10-1

51.

3 x

1014

Ec -0

.75

S4

0.88

1.4

x 10

-16

1.7

x 10

-14

4.2

-5.4

x 1

014E

c -0

.50

/ 0.6

5S3

*

0.84

1.7

x 10

-15

4.0

x 10

14E

c -0

.39

S20.

116

9.3

x 10

-16

5.5

x 10

13E

c -0

.23

S10.

026.

0 x

10-1

61.

4 x

1013

Ec -0

.15

S0

Trap

leve

l

*S

3 un

derg

oes

anne

alin

g at

T~4

00-4

70K;

the

para

met

ers

afte

r ann

ealin

g ar

e ty

pica

l of t

he le

vel

know

n fro

m th

e lit

erat

ure

as Z

1/Z2

DLT

S a

naly

sis

–A

rrhe

nius

Plo

t

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

24

68

1012

101

102

103

104

105

S1

S2B

S4

S3

S5

S0

S2

SiC

I4 v

irgin

SiC

G7

2 M

rSi

C A4

10

Mr

SiC

G1

40 M

rSi

C G

4 40

Mr u

p do

wn

KT

2/en (K

2 s)

1000

/T (K

-1)

600

400

200

300

100

DLT

S a

naly

sis

–Fi

lling

Kin

etic

s

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

01x

10-6

2x10

-63x

10-6

4x10

-65x

10-6

0.010.11

10-7

10-6

10-5

10-4

10-3

10-2

10-1

100

0

100

200

300

400

500

600

700

800

900

1000

a.u.

Tp (s

)

G1

306K

G1

449K

S4

3.06

E-1

7

S3

1.4E

-17

a.u.

Tp (s

)σ=cm

2

DLT

S a

nd a

nnea

ling

anal

ysis

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

5010

015

020

025

030

035

040

045

050

0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

S3

S2

S0 x 20

∆C/C (arb.units)

Tem

pera

ture

(K)

5010

015

020

025

030

035

040

045

050

0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

S2∆C/C (arb.units)

Tem

pera

ture

(K)

5010

015

020

025

030

035

040

045

050

0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

S4S2

B

S2∆C/C (arb.units)

Tem

pera

ture

(K)

5010

015

020

025

030

035

040

045

050

0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

S5

S2B

S1

S2∆C/C (arb.units)

Tem

pera

ture

(K)

5010

015

020

025

030

035

040

045

050

0

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.1

S5

S2∆C/C (arb.units)

Tem

pera

ture

(K)

1stan

neal

ing

stag

e

(360

–40

0 K

):

•ver

y st

rong

de

crea

se o

f pea

k S

2

•slig

ht a

mpl

itude

ga

in a

nd

tem

pera

ture

shi

ft of

S3

•S2B

and

S1

beco

me

reso

lved

2ndan

neal

ing

stag

e

(400

–47

0 K

) :

•blu

e sh

ift o

f S

3 ac

tivat

ion

ener

gy

•sha

rpen

ing

of

S3

peak

1. R

un 8

0-36

0K2.

Run

80-

400K

3. R

un 4

00-1

50K

4. R

un 1

60-4

70K

5. R

un 4

70-8

0K

C-V

ana

lysi

sD

efec

t ann

ealin

g in

4H

-SiC

A.C

aval

lini

Uni

vers

ity o

f Bol

ogna

INFM

01

23

45

1013

1014

1015

1016

as-g

row

n

irrad

iate

d -

afte

rre

cove

ry

Apparent concentration (cm-3)

X (µ

m)

irrad

iate

d -

befo

rere

cove

ry

•Str

ong

com

pens

atio

nof

free

cha

rge

for Φ

= 9.

48 x

1014

cm-2

(~1/

10 o

f th

e as

-gro

wn

valu

e).

•Sig

nific

ant f

ree

char

ge d

ensi

ty in

crea

se a

fter a

nnea

ling

of p

eak

S2at

360

K-4

00K

.

Pos

t-rec

over

y fre

e ch

arge

incr

ease

Pos

sibl

e ex

plan

atio

n:

reco

mbi

natio

n an

d an

nihi

latio

n of

the

defe

ct re

late

d to

leve

l S2

Pos

sibl

e ex

plan

atio

n:

reco

mbi

natio

n an

d an

nihi

latio

n of

the

defe

ct re

late

d to

leve

l S2

CC

E c

hara

cter

izat

ion

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

050

100

150

200

020406080100

G4

Φ=

9.48

x 1

014 e

/cm

2

CCE (%)

REV

ER

SE

BIA

S (V

)

Pre

-rec

over

y P

ost-r

ecov

ery

CC

E v

s. ir

radi

atio

n do

se

•In th

e di

ffusi

on re

gim

e (B

ias<

~160

V) C

CE

is

deg

rade

d by

the

intro

duct

ion

of tr

aps.

•In th

e dr

ift re

gim

e (B

ias>

~160

V) C

CE

sa

tura

tes

to 1

00%

for a

ll irr

adia

tion

dose

s.

CC

E vs

. ann

ealin

g

•Low

T a

nnea

ling

does

not

cha

nge

the

CC

E o

f the

det

ecto

r.

Con

clus

ions

D

efec

t ann

ealin

g in

4H

-SiC

A.C

aval

lini

Uni

vers

ity o

f Bol

ogna

INFM

•El

ectro

n irr

adia

tion

–In

trodu

ctio

n of

at l

east

4 tr

ap le

vels

. –

Stro

ng c

ompe

nsat

ion

of fr

ee c

arrie

r den

sity

.

•1st

Ann

ealin

g st

age

(360

K-4

00K

): –

Dis

appe

aran

ce o

f lev

el S

2 (E

c-0.

39 e

V).

–Fr

ee c

arrie

r den

sity

incr

ease

(rec

over

y).

–R

earra

ngem

ent o

f pea

k S

3.

•2nd

Ann

ealin

g st

age

(400

K-4

70K

): –

Blue

shi

ft of

S3

leve

l ene

rgy;

S3

para

met

ers

are

thos

e of

Z1/

Z2 le

vel.

•P

ossi

ble

reco

very

cau

se: a

nnih

ilatio

n of

the

defe

ct re

late

d to

S2

durin

g 1s

t an

neal

ing

stag

e (3

60K

-400

K).

•D

etec

tor p

erfo

rman

cepr

eser

ved

up to

Φ ~

1015

cm-2

.

-CC

E s

atur

ates

to 1

00%

in d

rift r

egim

e an

d re

mai

ns u

ncha

nged

upo

n an

neal

ing.

9 M

eV e

lect

ron

irrad

iatio

n on

C

dZnT

e

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

020

040

00

1000

2000

3000

4000

5000

6000

7000

counts

chan

nels

as-g

rown

0.2 M

rad

0.6 M

rad

0.8 M

rad

1.2 M

rad

1.6 M

rad

10

01

50

20

02

50

30

03

50

40

0

1x1

0-2

2x1

0-2

3x1

0-2

4x1

0-2

as

-gro

wn

0.2

Mra

d 0

.6 M

rad

0.8

Mra

d 1

.2 M

rad

1.6

Mra

d

H

W

Y

ZJ

XC

A1

A

te

mp

era

ture

(K

)

PICTS/IL0 (a.u.)

Gam

ma

Spe

ctro

scop

yP

ICTS

Tim

e re

cove

ry o

f 9 M

eV e

lect

ron

irrad

iate

d C

dZnT

e (6

mon

ths)

Def

ect a

nnea

ling

in 4

H-S

iCA

.Cav

allin

i

Uni

vers

ity o

f Bol

ogna

INFM

10

01

50

20

02

50

30

03

50

40

0

1x1

0-2

2x1

0-2

3x1

0-2

4x1

0-2

as-

gro

wn

1 M

rad

aft

er

irra

dia

tion

1 M

rad

aft

er

6 m

on

ths

D

H1

W

YJ

XC

A1

A

te

mp

era

ture

(K

)

PICTS/IL0 (a.u.)

010

020

030

040

00

1000

2000

3000

4000

5000

6000

7000

as-gr

own

1 Mr

ad af

ter irr

adiat

ion 1

Mrad

after

6 mo

nths

counts

chan

nels

PIC

TSG

amm

a S

pect

rosc

opy