ald and cvd of copper-based metallization for microelectronic … · 2013. 5. 1. · cu seed layer...
TRANSCRIPT
ALD
and
CV
D o
f Cop
per-B
ased
Met
alliz
atio
n fo
r M
icro
elec
troni
c Fa
bric
atio
n
Yeu
ngA
u, Y
oubo
Lin,
Hoo
nK
im, Z
heng
wen
Li,
and
Roy
G. G
ordo
nD
epar
tmen
t of C
hem
istry
and
Che
mic
al B
iolo
gyH
arva
rd U
nive
rsity
�Pe
riodi
c im
prov
emen
ts in
per
form
ance
of m
icro
elec
troni
c de
vice
s hav
e be
en a
chie
ved
thro
ugh
devi
ce-s
calin
g
Intro
duct
ion
�C
oppe
r was
sele
cted
bec
ause
of i
ts (1
) abu
ndan
ce, (
2) lo
w
resi
stiv
ity, a
nd (3
) bet
ter e
lect
rom
igra
tion
relia
bilit
y�
Dam
asce
ne p
roce
ss (E
P an
d C
MP)
is c
omm
only
ado
pted
fo
r pat
tern
ing
copp
er
Typi
cal D
amas
cene
Pro
cess
2
Out
line
In to
day’
s pre
sent
atio
n:
�A
LD a
nd C
VD
of C
u fil
ms f
rom
a
Cu(
I) a
mid
inat
epr
ecur
sor
�Fo
rmat
ion
of C
u se
ed la
yer b
y A
LD o
f Cu
and
by C
VD
of
CuO
N
�B
otto
m-u
p fil
ling
of C
VD
-Cu
and
CuM
nal
loy
in n
anos
cale
fe
atur
es
�Su
mm
ary
3
Cro
ss-S
ectio
n of
Mic
ropr
oces
sors
�R
equi
rem
ents
for g
ood
ALD
Cu
prec
urso
rs: (
1) th
erm
ally
stab
le, (
2) v
olat
ile, a
nd (3
) m
inim
al c
onta
min
atio
ns
Cop
per P
recu
rsor
s4
Copp
er (I
) N,N
'-di-s
ec-
buty
lace
tam
idin
ate
Mel
ting
Poin
t: ~
75C
Bub
bler
Tem
pera
ture
:130
CVa
por
Pres
sure
: ~0.
25 m
bar a
t 95
C
CuNN
N CuN
Adv
anta
ges o
fmet
al a
mid
inat
espr
ecur
sors
:�
Bid
enta
tech
ealti
ngef
fect
enh
ance
s the
rmal
stab
ility
�Tu
nabl
e re
activ
ity a
nd v
olat
ility
�M
inim
al c
arbo
nan
d ox
ygen
con
tam
inat
ion
B. S
. Lim
, A. R
ahtu
, J. S
. Par
k, a
nd R
. G. G
ordo
n, In
org.
Che
m.,
42(2
4), 7
951-
7958
, (20
03).
�C
oppe
r film
s cou
ld b
e de
posi
ted
by A
LD u
sing
mol
ecul
ar h
ydro
gen
as re
duci
ng a
gent
ALD
of C
oppe
r5
Ove
nH
eate
d C
ham
ber
Pum
p
H2
Cu(
I) a
md
�C
oppe
r dep
osite
d on
ALD
-Al 2O
3su
bstra
te a
t low
tem
pera
ture
s (15
0-19
0C
):
Z. L
i, A
. Rah
tu, a
nd R
. G. G
ordo
n, J
. Ele
ctro
chem
. Soc
.,15
3(1
1) C
787-
C79
4 (2
006)
AL
D S
yste
m
ALD
of C
oppe
r6
�G
row
th b
ehav
ior c
an b
e af
fect
ed b
y m
any
fact
ors:
surf
ace
chem
istry
, pre
curs
or
expo
sure
, dep
ositi
on te
mpe
ratu
re, e
tc.
AL
D-A
l 2O3,
AL
D-H
fO2,
The
rmal
SiO
2In
itial
ly ~
2Å/c
ycle
, ~0.
5Å/c
ycle
whe
n su
rfac
e is
fully
cov
ered
by
Cu
Ru
Subs
trat
es0.
11Å
/cyc
le
�A
LD h
as th
e ab
ility
to g
row
film
s con
form
ally
and
unifo
rmly
ove
r hig
h as
pect
ratio
ho
les a
nd tr
ench
es
Cop
per S
eed
Laye
r Usi
ng A
LD7
Z. L
i, R
. G. G
ordo
n, D
. F. F
arm
er, Y
. Lin
, and
J. V
lass
ak, E
lect
roch
em. S
olid
-Sta
te L
ett.,
8(7
) G18
2-G
185
(200
5)
AL
D C
u in
AR
= 3
5:1
Hol
es
�Fo
ur-p
oint
ben
d ex
perim
ent s
how
ed h
igh
adhe
sion
ene
rgie
s for
Cu/
Co/
WN
/SiO
2
In-s
ituR
esis
tanc
e M
easu
rem
ent
ALD
Cu
on G
lass
(185
C)
�C
oppe
r see
d la
yers
mus
t hav
e co
nfor
mal
step
cov
erag
e, st
rong
adh
esio
n an
d sm
ooth
su
rfac
e m
orph
olog
y
Cu
Seed
Lay
er U
sing
CV
D-C
uON
and
Plas
ma
Red
uctio
n8
H. K
im, H
. B. B
hand
ari,
S. X
u, a
nd R
.G. G
ordo
n, J
. Ele
ctro
chem
. Soc
., 15
5(7
) H
494-
H50
3 (2
008)
.
Taun
derl
ayer
100n
m
1μm
100n
m
Ru
unde
rlay
er
�Is
land
gro
wth
of C
VD
-Cu
on T
a un
derla
yer
�C
u ha
s fai
rly h
igh
wet
tabi
lity
on R
u, b
ut re
quire
s >20
nm to
form
a c
ontin
uous
film
due
to
isla
nd g
row
th
�N
ew a
ppro
ach:
Cu
prec
urso
r + H
2O�
Cu 2
OC
u pr
ecur
sor +
NH
3�
Cu 3
NC
u pr
ecur
sor
+ H
2O +
NH
3�
CuO
N
Low
Sur
face
Ene
rgy
(22-
26 m
J/m
2fo
r Cu 2
Oan
d C
u 3N
, com
pare
d to
170
0-19
00 m
J/m
2fo
r Cu)
Rem
ote
Hyd
roge
n Pl
asm
a R
educ
tion
near
RT
Thi
n (<
10 n
m),
Smoo
th
(RM
S ~1
nm
), H
igh
Den
sity
(95%
) CV
D
Cu
Seed
Lay
er
Thi
n (<
10 n
m),
Smoo
th
(RM
S ~1
nm
), H
igh
Den
sity
(95%
) CV
D
Cu
Seed
Lay
er
SiSiO
2
Ru
Ta/T
aN
Cu
Seed
Lay
er U
sing
CV
D-C
uON
and
Plas
ma
Red
uctio
n9
Ove
n
Hea
ted
Cha
mbe
r
Pum
p
H2
NH
3
N2
H2O
Cu(
I) a
md
CV
D S
yste
m
Tem
pera
ture
: 140
-220
°CPr
essu
re: 8
Tor
r
Rem
ote
Plas
ma
Gen
erat
or
Pum
p
Ar
H2
Plas
ma
Syst
em
Tem
pera
ture
: RT
-50°
CR
educ
tion
Tim
e: 3
0-18
0s0%20%
40%
60%
80%
100%
140
180
220
N O Cu
Com
posi
tion
of C
VD
-CuO
NFi
lms
(H2O
:NH
3=30
:10)
Cu
Seed
Lay
er U
sing
CV
D-C
uON
and
Plas
ma
Red
uctio
n10
Surf
ace
Mor
phol
ogy
of 2
0nm
of C
VD
-CuO
NFi
lms
(H2O
:NH
3=30
:10)
100
nm
Step
Cov
erag
e in
Hig
h A
R H
oles
(H2O
:NH
3=30
:10,
140
C)
140
C, 0
.64
nm16
0C
, 0.5
4 nm
180
C, 0
.72
nm22
0C
, 1.0
4 nm
Filli
ng N
arro
w F
eatu
res w
ith C
VD
of C
oppe
r�
Con
vent
iona
l tec
hniq
ues l
ead
to fo
rmat
ion
of v
oids
and
seam
s in
very
nar
row
feat
ures
�Io
dine
is a
cat
alyt
ic su
rfac
tant
that
pro
mot
es sm
ooth
er m
orph
olog
y an
d hi
gher
dep
osit
rate
�B
otto
m-u
p fil
ling
of su
b-m
icro
met
er fe
atur
es c
ould
be
achi
eved
by
CV
D
E. S
. Hw
ang
and
J. Le
e, C
hem
. Mat
er.,1
2, 2
076
(200
0).
K. S
him
, O. K
won
, H. P
ark,
W. K
oh, a
nd S
. Kan
g, J
. Ele
ctro
chem
. Soc
.,14
9(2
) G10
9-G
113
(200
2).
�Th
is p
roce
ss re
quire
s a c
onfo
rmal
Cu
seed
laye
r on
top
of th
e di
ffusi
on b
arrie
r and
ad
hesi
on la
yer
11
Surf
acta
nt C
atal
yzed
CV
D C
u an
d C
uMn
in N
arro
w T
renc
hes
Key
Poi
nts
�C
onfo
rmal
lyde
posi
ted
man
gane
se n
itrid
e se
rves
as
a b
arrie
r/adh
esio
n la
yer
�Io
dine
act
s as a
surf
acta
nt c
atal
yst t
o pr
omot
e C
u an
d M
ngr
owth
�Vo
id-f
ree,
bot
tom
-up
fillin
g of
Cu
or C
u-M
nal
loy
in n
arro
w tr
ench
es w
ith A
R u
p to
at l
east
5:1
�M
ndi
ffuse
s out
from
Cu
durin
g po
st-a
nnea
ling
to
furth
er im
prov
es a
dhes
ion
and
barr
ier p
rope
rties
at
Cu/
insu
lato
r int
erfa
ce
Mot
ivat
ion
Cu
Cu/
Mn
Cu/
Mn
Die
lect
ricsC
appi
ng L
ayer
Y. A
u, Y
. Lin
and
R. G
. Gor
don,
J. E
lect
roch
em. S
oc.,
158
(5)
D24
8-D
253
(201
1).
12
Che
mic
al V
apor
Dep
ositi
on o
f Cop
per
Prec
urso
rs
Copp
er (I
) N,N
'-di-s
ec-
buty
lace
tam
idin
ate
Mel
ting
Poin
t: ~
75°C
Bub
bler
Tem
pera
ture
:130
°CVa
por
Pres
sure
: ~0.
25 m
bar a
t 95°
C
CuNN
N CuN
CV
D S
yste
m
Tem
pera
ture
130°
C fo
r Mn 4
N18
0°C
for C
u an
d C
uMn
Pres
sure
: 5 T
orr
Bis
(N,N
'-di
isopr
opyl
pent
ylam
idin
ato)
man
gane
se(I
I)M
eltin
g Po
int:
~60
°CB
ubbl
er T
empe
ratu
re:9
0°C
Vapo
r Pr
essu
re: ~
0.1
mba
r at 9
0°C
NNN N
Mn
Ove
n
Hea
ted
Cha
mbe
r
Pum
p
H2
NH
3
N2
CH
3CH
2I
13
CV
D-M
n 4N
Bar
rier/A
dhes
ion
Laye
r�
CV
D-M
n 4N
(εph
ase,
FC
C st
ruct
ure)
can
be
prep
ared
by
reac
ting
man
gane
se a
mid
inat
epr
ecur
sors
with
NH
3
Die
lect
rics
CV
D-M
n 4N
RM
S ro
ughn
ess =
0.9
7 nm
for a
13.
5 nm
film
Exce
llent
step
cov
erag
e ho
les w
ith A
R =
52:
1
14
�M
n 4N
laye
r as t
hin
as 2
.5 n
m (1
) sho
ws b
arrie
r pro
perti
es a
gain
st C
u di
ffusi
on, (
2)
sign
ifica
ntly
impr
ove
adhe
sion
(deb
ondi
ng e
nerg
y =
6.5
J/m
2 ) b
etw
een
Cu
and
SiO
2
�R
elea
se o
f iod
ine
and
cata
lytic
effe
cts a
re o
bser
ved
on M
n 4N
unde
rlaye
r
Iodi
neEx
posu
reC
VD
-Cu
Dep
ositi
onC
VD
-Mn 4
ND
epos
ition
Surf
acta
nt C
atal
yzed
Bot
tom
-up
Filli
ng o
f CV
D-C
u
With
CV
D-M
n 4N
line
r la
yer
and
iodi
ne c
atal
yst,
tren
ches
with
wid
th �
20
nm a
nd a
spec
t rat
io o
ver
5:1
can
be c
ompl
etel
y fil
led
with
CV
D-C
u
15
Cu
Die
lect
rics
18 n
m S
truc
ture
26 n
m S
truc
ture
Cu
Surf
acta
nt C
atal
yzed
Bot
tom
-up
Filli
ng o
f CV
D-C
uMn
Allo
y
Cu-
Mn
Cu-
Mn
Die
lect
ricsC
appi
ng L
ayer
CV
D-M
n 4N
Dep
ositi
onIo
dine
Exp
osur
eC
VD
-CuM
nA
lloy
�C
u-M
nal
loy
can
be fo
rmed
by
(1) a
ltern
atin
g C
VD
-Cu
and
Mn
or (2
) co-
depo
sitin
g C
u an
d M
n
16
Tren
ches
with
wid
th �
30
nm c
an b
e co
mpl
etel
y fil
led
with
CuM
nal
loy
Man
gane
se c
once
ntra
tion:
0.5
-2.0
ato
mic
%
�In
sula
tors
enc
oura
ges d
iffus
ion
of M
nth
roug
h C
u gr
ain
boun
darie
s to
inte
rfac
e�
Mn
impr
oves
bot
h ad
hesi
on a
nd b
arrie
r pro
perti
es a
t the
inte
rfac
e
Enha
ncem
ent b
y D
iffus
ion
of M
nfr
om C
u to
Inte
rfac
e17
0246810121416
00.
10.
20.
30.
40.
50.
60.
7
Adhesion Energy(J/m2)
Mn/
Si R
atio
from
XPS
Inte
grat
ion
Si3N
4/C
uSi
O2/
Cu
Y. A
u, Y
. Lin
, H. K
im, E
. Beh
, Y. L
iu a
nd R
. G. G
ordo
n, J.
Ele
ctro
chem
. Soc
.,15
7(6
) D34
1-D
345
(201
0).
Sum
mar
y
�C
oppe
r can
be
depo
site
d by
ALD
or C
VD
usi
ng a
Cu(
I) a
mid
inat
epr
ecur
sor
�C
onfo
rmal
and
uni
form
seed
laye
rs c
an b
e pr
epar
ed b
y A
LD-C
u or
by
CV
D-C
uON
follo
wed
by
rem
ote
hydr
ogen
pla
sma
redu
ctio
n
�N
anos
cale
tren
ches
can
be
supe
rcon
form
ally
fille
d by
CV
D-C
u an
d C
VD
-CuM
nal
loy
with
an
iodi
ne su
rfac
tant
on
Mn 4
N li
ner l
ayer
�M
anga
nese
in C
u-M
nal
loy
diffu
ses o
ut to
stre
ngth
en th
e in
terf
ace
betw
een
Cu
and
insu
lato
rs w
ithou
t inc
reas
ing
the
resi
stiv
ity o
f Cu
�M
anga
nese
silic
ate
(MnS
i xOy)
inte
rfac
ial l
ayer
show
s exc
elle
nt b
arrie
r pr
oper
ties a
gain
st C
u di
ffusi
on a
nd p
rote
cts C
u fr
om c
orro
sion
by
H2O
and
O2
18
Ack
now
ledg
emen
ts�
Faci
litie
s at H
arva
rd’s
Cen
ter f
or N
anos
cale
Syst
ems (
CN
S), a
mem
ber o
f the
Nat
iona
l N
anot
echn
olog
y In
fras
truct
ure
Net
wor
k (N
NIN
), su
ppor
ted
by th
e N
atio
nal S
cien
ce
Foun
datio
n
�Pr
ecur
sors
: Dow
Che
mic
al C
ompa
nySu
bstra
tes a
nd A
naly
ses:
App
lied
Mat
eria
ls, I
MEC
and
IBM
�M
embe
rs o
f Gor
don
Gro
up
19