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Bi(Pb)SCaCuO thin films on piezoelectric PbTiO3
PI ICA
Physica C i 8 5 - 1 8 9 (1991) 2125-2126 North-Holland
Bi(Pb)-Sr-Ca-Cu-O THIN FILMS ON PIEZOELECTRIC PbTiO 3 Masahiro AKINAGA and Hideaki FUKUDA D e p a r t m e n t of Physics, Fukuoka University of Education, Fukuoka 811-41, Japan
We r e p o r t on our progress in the f a b r i c a t i o n and c h a r a c t e r i z a t i o n of high-To Bi(Pb)-Sr-Ca-Cu-O thin films prepared on the in-house grown PbTiOq s u b s t r a t e with p i e z o e l e c t r i c i t y . "The e l e c t r i c a l properties strongly depend on the c - a x i s o r i e n t a t i o n rgtio of the PbTiO 3 s u b s t r a t e and t e m p e r a t u r e dependence of the c r i t i c a l current is s i m i l a r to that in SNS-type weak link.
1. INTRODUCTION The on
fabrication
piezoelectric
not
only
of
superconducting
substrate
from
crystallography
SAMPLE PREPARATION
2.
but
is
very
film
important
the
viewpoint
of
also
from
viewpoint
the
the
We
chose
PbTiO 3
piezoelectric material. p i e z o e l e c t r i c i t y2 axis
measurement
superconducting
film. out
Acoustic in
the
porous
sound
experimental
wave for
complicated
total
a
best
works
bulk sample 1 could
responsible be
superconducting
absorption
by
way
to
use
high frequencies in single c r y s t a l oriented
film.
coefficient
of
is
Because
proportional
to
the
square
~_,,.~"'4 ~hp. _ ,nnrnsi~Y ....... can from
the
We
propagating
have
films
on
electric step
resolution
of
films
substrate
properties,
toward
path
this
on and study
the c a r r i e r s frequency
much
more
sound wave. PbTiO 3
superconducting piezoelectric
investigated
grown
film~
~ood
PbTiO3/MgO
were
deposited
rf-sputtering
their
method.
m~:thod The
The
have
details been
p i e z o e l e c t r i c i t y of
of
the
described these
films
were c o n f i r m e d by detecting the SAW propagating on the film using interdigital e l e c t r o d e s fabricated by
iift-off
Cu-O
films
substrate a
photolithography 5. were
described
single
deposited above
target
on
PbTiO3/MgO
by rf-sputtering using
whose
BI0.8Pb0.2Ca ~.0Cu i .4Oy,
i31{Pbi-Sl-~a-
composition
and
annealed
was on
a
bulk c e r a m i c in air.
should he a first
the
SAW
measurement
the
manifestation
for
mechanism
the
3. EXPERI]MENTAL RESULTS
In
of the
the high-T c superconductivity.
I:ig.
1
the.
normalized
Bi-compound
~-Financially supported in part Science and Culture, Japan.
also
expected
between
FbTiO 3
oxide
by
the
the
been we
of
more
piezoelectric and
have
con
much
eleswhere 4.
the
Most
highly grows
on polistled single crystalline MgO (100) substrates
attenuation
to
with
structure
matching
perovskite
the
must
film or highly
of
of
The
the
of
it
preparation
excluded
substrate
Bi(Pb)-Sr-Ca-Cu-O PbTiO3/MgO
be
fabricated
MgO
due
carriers
film
Then
and superconducting films.
the
sound waves
films
substrate.
the
from
with
MgO
substrate
substrate 3.
crystallographic
Then
SAW
carried
on
MgO
not s e p a r a t e
superconductivity absorption.
thin
the
perovskite
the
high-T c
a
Becuase ?t has remarkable
and
oriented
of the step toward s u r f a c e a c o u s t i c wave (SAW) in
as
All fights rescrvcd.
electrical
samples
by Grant-in-Aid for Scientific Research
0921-4534/91/$03.50 © 1991 - Elscvicr Science PuNishcvs B.V.
temperature
from
on
ci~:~t:~e~i,J,~n<:c5 ~
resistivitv PbTiO 3
for various
with
differeut
the Ministry of Ldt~t_'. ......
M. Akinaga, H. Fulaufa / Bi(Pb)-Sr-Ca-Cu-O thin films on piezoelectric Pb TiO~
2126
,2[
~
tQi.
1.0
I
0.8
'""-.
.8
oe
d 0.6
0
o.
.,. 0.t-
BPTI2A =---45Z: R==892.aD ,', BPTa4.B~=66g. R,.,,=65.72fl " BPT34.C=---54,Z.R=,=384..70 = BPT35C==65~. R==55.74.0
:l
J
.2 50
150
100
200
250
c-axis
orientation
ratio
a,
which
is
samples
(XRD) a
small
phase
and
a
phase.
XRD
the Bi-compound phase
and
The
samples
on
showed
a
resistive drastic
patterns a
very
•
0
also
better
resistivity
sample
at
model
due
suggested
to that
others. value
of
properties.
The
temperature Ic
in
temperature
dependence
the
PbTiOJMgO were also o is defined as the current drop
between
uV/mm. current where
and
the
probes
measured° at
which
rises
critical
films
on
Here
.~ c the voltage
to
above
0.2
In Fig. 2 typical plots of the normalized versus Tcf
result
thermal
the
of
Bi-compound
reduced
= 65.7 for
temperature
K, are
shown
YBa2Cu3074
decomposion
method
film by
t
= T/Tel ,
together made Klee
%
0.4- 0.6 t
,
.
=
0.8
1.0
of
model
SNS junction data
where
separated
broken lie
the
curves
represent
and SIS junction 7. near
the
curve
superconducting
by normal
array
metal
barrier.
The
of
SNS
grains
are
The
fitting
plots seem to suggest that the model is applicable to tllm
our
sample.
surface,
Also a
nearly
the
SEM
void-free
analysis
of
feature
the with
layered s t r u c t u r e is consistent with the model.
a small
metalic behavior in the normal s t a t e .
current
and
experimental
showed
room
solid
due
superconductive the
The
change
higher
. ~
FIGURE 2 Normalized critical current vs. reduced temperature for Bi(Pb)2Sr~CaCu20 film on PbTiO 3 (o~ and for YBa,~C~uoO., 6 Yfilm by M. Klee et al. (®). Solid and ISrok~n'curves7represen t the model of SNS and SIS junction a r r a y .
All
amount
with
.
0.2
0
(100).
change
small
PbTiO 3
increasing ~ ,
electrical
and
films consist of e-axis oriented
2212
With
(001)
showed
2223
2212
peaks
k \
defined
as a ratio of the intensity of the X - r a y powder diffraction
\
0.2
300
FIGURE 1 Temperature dependences of the normalized electrical resistivity for the films on PbTiO 3 substrate with c-axis orientatio r a t i o a .
\
o o
"-u
TIKI
the
\
o
.4.
to
\
o
U
~.6 er
S-I-S mdel
with
by the et
al 6.
REFERENCES 1. for example, K.J. Sun et al., Phys. Lett. A 131 (1988) 541. 2. T. Y a m a d a et al., Jpn. J. Appl. Phys. 6 (1967) 151. 3. K. lijima et al., J. Appl. Phys. 60 (1986) 36~. 4. M. Akinaga et at., Proc. 3rd Int. Conf. Prop. and Appl. of Dielectric Materials, Tokyo, 1991 (IEVE, New York, 1991) 659. 5. The SAW d e t e c t i o n was p e r f o r m e d in cooparation with Prof. T. Fukami and T. Aom~ne and Dr, H. Ohkuboo 6. M. Klee et al,, Jo Crystal Growth 91 (1988) 346. 7. j.W.C, de Vrie~ et al., Physica C (1989) 406.
Physica C i 8 5 - 1 8 9 (1991) 2125-2126 North-Holland
Bi(Pb)-Sr-Ca-Cu-O THIN FILMS ON PIEZOELECTRIC PbTiO 3 Masahiro AKINAGA and Hideaki FUKUDA D e p a r t m e n t of Physics, Fukuoka University of Education, Fukuoka 811-41, Japan
We r e p o r t on our progress in the f a b r i c a t i o n and c h a r a c t e r i z a t i o n of high-To Bi(Pb)-Sr-Ca-Cu-O thin films prepared on the in-house grown PbTiOq s u b s t r a t e with p i e z o e l e c t r i c i t y . "The e l e c t r i c a l properties strongly depend on the c - a x i s o r i e n t a t i o n rgtio of the PbTiO 3 s u b s t r a t e and t e m p e r a t u r e dependence of the c r i t i c a l current is s i m i l a r to that in SNS-type weak link.
1. INTRODUCTION The on
fabrication
piezoelectric
not
only
of
superconducting
substrate
from
crystallography
SAMPLE PREPARATION
2.
but
is
very
film
important
the
viewpoint
of
also
from
viewpoint
the
the
We
chose
PbTiO 3
piezoelectric material. p i e z o e l e c t r i c i t y2 axis
measurement
superconducting
film. out
Acoustic in
the
porous
sound
experimental
wave for
complicated
total
a
best
works
bulk sample 1 could
responsible be
superconducting
absorption
by
way
to
use
high frequencies in single c r y s t a l oriented
film.
coefficient
of
is
Because
proportional
to
the
square
~_,,.~"'4 ~hp. _ ,nnrnsi~Y ....... can from
the
We
propagating
have
films
on
electric step
resolution
of
films
substrate
properties,
toward
path
this
on and study
the c a r r i e r s frequency
much
more
sound wave. PbTiO 3
superconducting piezoelectric
investigated
grown
film~
~ood
PbTiO3/MgO
were
deposited
rf-sputtering
their
method.
m~:thod The
The
have
details been
p i e z o e l e c t r i c i t y of
of
the
described these
films
were c o n f i r m e d by detecting the SAW propagating on the film using interdigital e l e c t r o d e s fabricated by
iift-off
Cu-O
films
substrate a
photolithography 5. were
described
single
deposited above
target
on
PbTiO3/MgO
by rf-sputtering using
whose
BI0.8Pb0.2Ca ~.0Cu i .4Oy,
i31{Pbi-Sl-~a-
composition
and
annealed
was on
a
bulk c e r a m i c in air.
should he a first
the
SAW
measurement
the
manifestation
for
mechanism
the
3. EXPERI]MENTAL RESULTS
In
of the
the high-T c superconductivity.
I:ig.
1
the.
normalized
Bi-compound
~-Financially supported in part Science and Culture, Japan.
also
expected
between
FbTiO 3
oxide
by
the
the
been we
of
more
piezoelectric and
have
con
much
eleswhere 4.
the
Most
highly grows
on polistled single crystalline MgO (100) substrates
attenuation
to
with
structure
matching
perovskite
the
must
film or highly
of
of
The
the
of
it
preparation
excluded
substrate
Bi(Pb)-Sr-Ca-Cu-O PbTiO3/MgO
be
fabricated
MgO
due
carriers
film
Then
and superconducting films.
the
sound waves
films
substrate.
the
from
with
MgO
substrate
substrate 3.
crystallographic
Then
SAW
carried
on
MgO
not s e p a r a t e
superconductivity absorption.
thin
the
perovskite
the
high-T c
a
Becuase ?t has remarkable
and
oriented
of the step toward s u r f a c e a c o u s t i c wave (SAW) in
as
All fights rescrvcd.
electrical
samples
by Grant-in-Aid for Scientific Research
0921-4534/91/$03.50 © 1991 - Elscvicr Science PuNishcvs B.V.
temperature
from
on
ci~:~t:~e~i,J,~n<:c5 ~
resistivitv PbTiO 3
for various
with
differeut
the Ministry of Ldt~t_'. ......
M. Akinaga, H. Fulaufa / Bi(Pb)-Sr-Ca-Cu-O thin films on piezoelectric Pb TiO~
2126
,2[
~
tQi.
1.0
I
0.8
'""-.
.8
oe
d 0.6
0
o.
.,. 0.t-
BPTI2A =---45Z: R==892.aD ,', BPTa4.B~=66g. R,.,,=65.72fl " BPT34.C=---54,Z.R=,=384..70 = BPT35C==65~. R==55.74.0
:l
J
.2 50
150
100
200
250
c-axis
orientation
ratio
a,
which
is
samples
(XRD) a
small
phase
and
a
phase.
XRD
the Bi-compound phase
and
The
samples
on
showed
a
resistive drastic
patterns a
very
•
0
also
better
resistivity
sample
at
model
due
suggested
to that
others. value
of
properties.
The
temperature Ic
in
temperature
dependence
the
PbTiOJMgO were also o is defined as the current drop
between
uV/mm. current where
and
the
probes
measured° at
which
rises
critical
films
on
Here
.~ c the voltage
to
above
0.2
In Fig. 2 typical plots of the normalized versus Tcf
result
thermal
the
of
Bi-compound
reduced
= 65.7 for
temperature
K, are
shown
YBa2Cu3074
decomposion
method
film by
t
= T/Tel ,
together made Klee
%
0.4- 0.6 t
,
.
=
0.8
1.0
of
model
SNS junction data
where
separated
broken lie
the
curves
represent
and SIS junction 7. near
the
curve
superconducting
by normal
array
metal
barrier.
The
of
SNS
grains
are
The
fitting
plots seem to suggest that the model is applicable to tllm
our
sample.
surface,
Also a
nearly
the
SEM
void-free
analysis
of
feature
the with
layered s t r u c t u r e is consistent with the model.
a small
metalic behavior in the normal s t a t e .
current
and
experimental
showed
room
solid
due
superconductive the
The
change
higher
. ~
FIGURE 2 Normalized critical current vs. reduced temperature for Bi(Pb)2Sr~CaCu20 film on PbTiO 3 (o~ and for YBa,~C~uoO., 6 Yfilm by M. Klee et al. (®). Solid and ISrok~n'curves7represen t the model of SNS and SIS junction a r r a y .
All
amount
with
.
0.2
0
(100).
change
small
PbTiO 3
increasing ~ ,
electrical
and
films consist of e-axis oriented
2212
With
(001)
showed
2223
2212
peaks
k \
defined
as a ratio of the intensity of the X - r a y powder diffraction
\
0.2
300
FIGURE 1 Temperature dependences of the normalized electrical resistivity for the films on PbTiO 3 substrate with c-axis orientatio r a t i o a .
\
o o
"-u
TIKI
the
\
o
.4.
to
\
o
U
~.6 er
S-I-S mdel
with
by the et
al 6.
REFERENCES 1. for example, K.J. Sun et al., Phys. Lett. A 131 (1988) 541. 2. T. Y a m a d a et al., Jpn. J. Appl. Phys. 6 (1967) 151. 3. K. lijima et al., J. Appl. Phys. 60 (1986) 36~. 4. M. Akinaga et at., Proc. 3rd Int. Conf. Prop. and Appl. of Dielectric Materials, Tokyo, 1991 (IEVE, New York, 1991) 659. 5. The SAW d e t e c t i o n was p e r f o r m e d in cooparation with Prof. T. Fukami and T. Aom~ne and Dr, H. Ohkuboo 6. M. Klee et al,, Jo Crystal Growth 91 (1988) 346. 7. j.W.C, de Vrie~ et al., Physica C (1989) 406.