ADVANCED CERAMIC SYSTEMS FOR ADVANCED CERAMIC SYSTEMS FOR THE TELECOMMUNICATION INDUSTRYTHE TELECOMMUNICATION INDUSTRYADVANCED CERAMIC SYSTEMS FOR ADVANCED CERAMIC SYSTEMS FOR

THE TELECOMMUNICATION INDUSTRYTHE TELECOMMUNICATION INDUSTRY

Participants:Participants:

TKI-Ferrit Development and Manufacturing Ltd.TKI-Ferrit Development and Manufacturing Ltd.

KŐPORC Development Ltd.KŐPORC Development Ltd.

Research Institute for Technical Physics and Research Institute for Technical Physics and Materials Science of the Hungarian Academy of Materials Science of the Hungarian Academy of

SciencesSciencesHead of the project: Anna SztaniszlavHead of the project: Anna Sztaniszlav

TKI-Ferrit Ltd.TKI-Ferrit Ltd.

H-1142 BudapestH-1142 Budapest

Ungvár u. 64-66Ungvár u. 64-66

HungaryHungary

sztanisz@tki-ferrit.husztanisz@tki-ferrit.hu

Introduction:Introduction:Microwave ferrite devicesMicrowave ferrite devices ( isolators, circulators) are irreplaceable components for the telecommunication industry. Transmission parameters (insertion loss, isolation, etc.) and the working temperature range of the ferrite devices depend strongly on the dielectric losses, other microwave parameters and temperature dependence of the microwave parameters of applied materials, such as the soft ferritessoft ferrites and dielectric ceramicsdielectric ceramics which are used as circuit components or tuning elements.

What is “ferrite device”?It is a nonreciprocal passive unit, which is an irreplaceable

component for the telecommunication industry.

Main components of ferrite devices:

Ceramic dielectric

Circuit unit

ferrite

Main components of ferrite devices:

ferrite

Ceramic dielectric

Circuit unit

Tuning component

Main applied material systems in ferrite devices:

•Permanent magnets

It is not a topic of this development

•Soft ferrites (MeFe2O4), garnet materials(YFe5O12)

•Ceramic dielectrics (BaO/TiO2, TiO2/ZrO2, MgTiO3/ZnTiO3)

Soft ferrites (MeFe2O4), garnets (YFe5O12)Spinel ferrites

MnxMgyFezO4 x+y+z=3

typical substitutions:: Al, Zn,…

NiFe2O4

typical substitutions : Al, Co, Zn, Mn, Bi, ..

Li0,5Fe2-0,5O4

typical substitutions : Zn, Ti, Bi, Mn, …

Garnets

Y3Fe5O12

typical substitutions : Al, Gd, Ca, V. In, Zr, Ho,…

all cations, where the ionic radius is between 0,26 és 1,29 AMost important material parameters:

saturation magnetisationdielectric constant ( min. 10, max. 20)magnetic (ΔH) and dielectric (tg δ)lossestemperature dependence of the above mentioned parameters

Which material systems are investigated ?

•Ceramic dielectrics

TiO2 based dielectrics ε= 80-100

TiO2/ZrO2, ε= 16

BaO/TiO2 ε= 40

MgTiO3/ZnTiO3) ε= 26-80

composites

applications: active circuit components (dielectric constant: 6-100)tuning elements

most important parameters:dielectric constantdielectric lossestemperature dependence of the above mentioned parameters

Which material systems are investigated ?

Harmonised development of the ferrite/garnet and Harmonised development of the ferrite/garnet and ceramic dielectric systemsceramic dielectric systems to produce isolators, circulators

with a very broad working frequency range,

with very low (<0,2 dB) insertion loss

with very broad working temperature range (-400C +800C) in the possibly smallest dimension

Aim of this project:Aim of this project:

•To cover the demand of the modern telecommunicationwireless systems (900 MHz, 1800 MHz, 2400 MHz,..)

TETRA systems : 400 MHz, 800 MHz),…...

radars, etc.

•to develop multifunctional devices to develop multifunctional devices

•to increase the working temperature range of the ferrite devicesto increase the working temperature range of the ferrite devices (-400C ÷ +850C)

•to improve the transmission parametersto improve the transmission parameters (insertion loss :<0,2 dB)

by the reduction of the loss factors of the ferrites, ceramic dielectrics

•to reduce the size and price of the devicesto reduce the size and price of the devices

It depends on the dielectric constants

•to increase the power handling of the devices (kW)to increase the power handling of the devices (kW)

It depends on the chemical composition and morphology of the two

material systems.

Material parameters have to be matched:Material parameters have to be matched:

• temperature dependence of the saturation temperature dependence of the saturation magnetisation of magnetisation of the ferrite/garnet the ferrite/garnet

• temperature dependence of dielectric temperature dependence of dielectric constant of the ceramic constant of the ceramic dielectricdielectric

• dielectric losses of the ferrite/garnet and dielectric losses of the ferrite/garnet and ceramic dielectricsceramic dielectrics

• dielectric constant of the ferrite/garnet and dielectric constant of the ferrite/garnet and ceramic ceramic dielectricsdielectrics

TASKS :TASKS :

•Development of new material compositions :Development of new material compositions :

•To develop ferrites, garnets with different chemical compositions

•To develop ceramic dielectrics with different chemical compositions

•Technological developmentTechnological development (advanced pressing methods) to get

• Homogeneous grain size distribution

• High density materials

• Ferrites and garnets with very small grain sizes for special application (high power devices) by HIP technique / nanoferrite technique

•Elaboration of new investigation methodsElaboration of new investigation methods (to investigate the chemical composition, chemical homogeneity, morphology)

•Development of high sensitive methods

•Development new evaluation software

•Design and preparation of new ferrite devices .

•Investigation of theoratical questions:

correlation between the different material parameters and the transmission parameters of the devices

Recent results:A. Anna Sztaniszlav

Microwave Ferrite Research and Development in Central Europe

Ferrites. Proceedings of the ICF 8. Kyoto 2000. P.825-829 Invited

A. Anna Sztaniszlav, M. Balla, M. Farkas-Jahnke

Solid State Reactions in the Fe2O3-CaCO3-In2O3 System

Journal opf Materials Science 25. (1990) p. 2353-2358

A. Anna Sztaniszlav, M. Balla, M. Farkas-Jahnke

Garnet Forming Solid State Reactions in FeYCaZrO Systems with Different Y-Fe Ratios

Physica Scripta 40. P. 321-324 (1989)

L. Bartha, P. Arató, A.L. Tóth, R. Porat, S. Berger, A. Rosen

Investigation of HIP Sintering of Nanocrystalline WCCo Powder

Journal of Advanced Materials 32, p. 23-26. (2000)