NEW MULTIFUNCTIONAL CERAMICS: ELABORATION, NEW MULTIFUNCTIONAL CERAMICS: ELABORATION, CHARACTERIZATIONS AND APPLICATIONSCHARACTERIZATIONS AND APPLICATIONS

University of Science and Technology Houari Boumediene (USTHB)University of Science and Technology Houari Boumediene (USTHB)Taïbi – Benziada Aldjia – Laldja (http://perso.usthb.dz/~lbenziada)

Agence Thématique de Recherche en Sciences et Technologie (ATRST) Avenue Pasteur, ENSA ex INA Belfort,B.P 62 – Hacene Badi, El-Harrach, Alger

Tél : 021 52 68 01 / 02 – Fax : 021 52 62 40 – E-mail : Contacts@atrst.dzhttp://www.atrst.dz

INTRODUCTIONINTRODUCTION

MaterialsMaterials have always represented an essential have always represented an essential aspect of aspect of Human Society Human Society but, nowadays, the but, nowadays, the MaterialMaterial became synonymous with became synonymous with Existence Existence for anyfor any IndustryIndustry. . For example, in New Technologies of Information and For example, in New Technologies of Information and Communication (Communication (NTICNTIC), the ), the Progress Progress and and SuccessSuccess are closely linked to the development of are closely linked to the development of Advanced Advanced CeramicsCeramics with with higher higher and and higher performances higher performances but but also with also with lowerlower and and lowerlower factory factory cost cost to be to be competitive competitive on the huge market of microelectronics .on the huge market of microelectronics .

INTEREST FOR MATERIALSINTEREST FOR MATERIALS

ABOABO3 3 RELATED MATERIALSRELATED MATERIALS

Among the new engineering ceramics, Among the new engineering ceramics, ABOABO3 3

perovskitesperovskites share several properties like share several properties like piezoelectricitypiezoelectricity, , pyroelectricitypyroelectricity and and ferroelectricityferroelectricity that that make them very attractive for make them very attractive for Microelectronic IndustryMicroelectronic Industry. . Moreover, with the devices Moreover, with the devices miniaturizationminiaturization, , ATiOATiO33 (A = (A =

Ca, Sr, Ba) ceramics became Ca, Sr, Ba) ceramics became key materialskey materials for the for the development of development of smart systemssmart systems with with artificial artificial intelligenceintelligence. Up to now, the varied . Up to now, the varied PZT PZT have have dominated the market of dominated the market of microelectronic componentsmicroelectronic components. . However, theHowever, the toxicitytoxicity of of PbPb is a serious is a serious threatthreat to to human healthhuman health and and environmentenvironment . Therefore, extensive . Therefore, extensive research is actually oriented toward the research is actually oriented toward the developmentdevelopment of of green materialsgreen materials..

CERAMIC PRODUCTSCERAMIC PRODUCTS

Among the various applications of Among the various applications of ABOABO33 materials we materials we

can cite as examples: can cite as examples:

• CapacitorsCapacitors• SensorsSensors• ResonatorsResonators• Piezoelectric actuatorsPiezoelectric actuators• Pyroelectric infrared detectorsPyroelectric infrared detectors• Electro-optical modulatorsElectro-optical modulators• Computer memories...Computer memories...

APPLICATIONS OF PEROVSKITESAPPLICATIONS OF PEROVSKITES

FRAMsFRAMs

DRAMsDRAMs

HDDHDD

T. Shiosaki, The recent progress in the research and development for ferroelectric memory in Japan (1997)T. Shiosaki, The recent progress in the research and development for ferroelectric memory in Japan (1997)

CONCLUSIONSCONCLUSIONS

• Bulk ceramics Bulk ceramics AA1-x1-xMMxxTiTi1-x1-xLiLixxOO3-3x3-3xFF3x3x (A = Ca, Sr or Ba) have been(A = Ca, Sr or Ba) have been sintered at low temperature sintered at low temperature thanks to thanks to

the admixture MFthe admixture MF2 2 (M= Ca or Pb) and LiF fluorides.(M= Ca or Pb) and LiF fluorides.

• The oxifluorides deriving from The oxifluorides deriving from CaTiOCaTiO33 are promising materials to manufacture are promising materials to manufacture class I capacitors class I capacitors and and

resonators resonators for microwave circuits.for microwave circuits.

• ((Sr,M)(Ti,Li)(O,F)Sr,M)(Ti,Li)(O,F)33 ceramics could be used in ceramics could be used in piezoelectric devices piezoelectric devices and are potential candidates for the and are potential candidates for the

fabrication of fabrication of type I capacitorstype I capacitors..

• The ceramics related to The ceramics related to BaTiOBaTiO33 could be of interest for could be of interest for Z5U multilayer capacitors Z5U multilayer capacitors or as or as filters filters for for

electromagnetic waveselectromagnetic waves in various devices. in various devices.

• Moreover, all these fluorinated materials could be used as Moreover, all these fluorinated materials could be used as photocatalysts photocatalysts in Hin H22O decomposition to get O decomposition to get

clean energyclean energy. .

SAMPLES PREPARATIONSAMPLES PREPARATION

ACO3+TiO2

Grinding, Calcination

ATiO3 + CO2

Grinding, Pressing (108 Pa)

Sintering (900 °C or 1000 °C , 1 or 2 h)

x MF2 + x LiF

A1-xMx(Ti1-xLix )O3-3x F3x

MICROSTRUCTURESMICROSTRUCTURES

CaTiCaTi0.950.95LiLi0.050.05OO2.852.85FF0.150.15

= 21.9 %

BaBa0.950.95CaCa0.050.05TiTi0.950.95LiLi0.050.05OO2.852.85FF0.150.15

= 13.5 %= 13.5 %

SrSr0.950.95CaCa0.050.05TiTi0.950.95LiLi0.050.05OO2.852.85FF0.150.15

= 18.7 %= 18.7 %

BaBa0.970.97PbPb003003TiTi0.970.97LiLi0.030.03OO2.912.91FF0.090.09

= 16.9 %= 16.9 %

DIELECTRIC PROPERTIESDIELECTRIC PROPERTIES

100 200 300 400 500 6000

100

200

300

400

500

600

700

800

900 102Hz

5.102Hz

10.102Hz

50.102Hz

100.102Hz

500.102Hz

1000.102Hz

2000.102Hz

' r

T(°C)

ε'r

T (K)

102 Hz

5x102 Hz

103 Hz

5x103 Hz

104 Hz

5x104 Hz

105 Hz

2x105 Hz

100 200 300 400 500 600

0

200

400

600

800

1000 102Hz

5.102Hz

10.102Hz

50.102Hz

100.102Hz

500.102Hz

1000.102Hz

2000.102Hz

T(°C)

'' r

ε"r

T (K)

102 Hz

5x102 Hz

103 Hz

5x103 Hz

104 Hz

5x104 Hz

105 Hz

2x105 Hz

5,0 5,5 6,0 6,5 7,0 7,5 8,00

10

20

30

40

50

60

70

80

90

100

logf(Hz)

0

1

2

3

4

5

6

7

8

9

10

''

r

'

r

CaTiCaTi0.950.95LiLi0.050.05OO2.852.85FF0.15 0.15 ceramicceramic

6,0 6,5 7,0 7,5 8,0 8,5 9,0

-200

-100

0

100

200

300

400

500

Co

mp

lex

per

mit

tivi

ty

log10

f (Hz)

'

"

102 Hz

5x102 Hz

103 Hz

5x103 Hz

104 Hz

5x104 Hz

105 Hz

2x105 Hz

102 Hz5x102 Hz

103 Hz

5x103 Hz104 Hz5x104 Hz105 Hz2x105 Hz

SrSr0.950.95CaCa0.050.05TiTi0.950.95LiLi0.050.05OO2.852.85FF0.15 0.15 ceramicceramic

ε"rε'r

BaBa0.970.97PbPb0.030.03TiTi0.970.97LiLi0.030.03OO2.912.91FF0.09 0.09 ceramicceramic

log10f (Hz)

ε"r

ε'r 3000

2000

1000

4000

5 6 7 8 0

BaBa0.950.95CaCa0.050.05TiTi0.950.95LiLi0.050.05OO2.852.85FF0.15 0.15 ceramicceramic