ADVANCED CERAMIC SYSTEMS FOR THE TELECOMMUNICATION INDUSTRY Participants: TKI-Ferrit Development and Manufacturing Ltd. KŐPORC Development Ltd. Research Institute for Technical Physics and Materials Science of the Hungarian Academy of Sciences Head of the project: Anna Sztaniszlav TKI-Ferrit Ltd. H-1142 Budapest Ungvár u

Introduction: Microwave ferrite devices soft ferritesdielectric ceramics Microwave 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 ferrites and dielectric 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 (MeFe 2 O 4 ), garnet materials(YFe 5 O 12 ) Ceramic dielectrics (BaO/TiO 2, TiO 2 /ZrO 2, MgTiO 3 /ZnTiO 3 )

Soft ferrites (MeFe 2 O 4 ), garnets (YFe 5 O 12 ) Spinel ferrites Mn x Mg y Fe z O 4 x+y+z=3 typical substitutions::Al, Zn,… NiFe 2 O 4 typical substitutions :Al, Co, Zn, Mn, Bi,.. Li 0,5 Fe 2-0,5 O 4 typical substitutions :Zn, Ti, Bi, Mn, … Garnets Y 3 Fe 5 O 12 typical substitutions :Al, Gd, Ca, V. In, Zr, Ho,… all cations, where the ionic radius is between 0,26 és 1,29 A Most important material parameters: saturation magnetisation dielectric constant ( min. 10, max. 20) magnetic (ΔH) and dielectric (tg δ)losses temperature dependence of the above mentioned parameters Which material systems are investigated ?

Ceramic dielectrics TiO 2 based dielectricsε= TiO 2 /ZrO 2,ε= 16 BaO/TiO 2 ε= 40 MgTiO 3 /ZnTiO 3 ) ε= composites applications: active circuit components (dielectric constant: 6-100) tuning elements most important parameters: dielectric constant dielectric losses temperature dependence of the above mentioned parameters Which material systems are investigated ?

Harmonised development of the ferrite/garnet and ceramic dielectric systems Harmonised development of the ferrite/garnet and ceramic 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 (-40 0 C C) in the possibly smallest dimension Aim of this project:

To cover the demand of the modern telecommunication wireless 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 devices to increase the working temperature range of the ferrite devices (-40 0 C ÷ C) to improve the transmission parameters to 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 devices to 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: temperature dependence of the saturation magnetisation of the ferrite/garnettemperature dependence of the saturation magnetisation of the ferrite/garnet temperature dependence of dielectric constant of the ceramic dielectrictemperature dependence of dielectric constant of the ceramic dielectric dielectric losses of the ferrite/garnet and ceramic dielectricsdielectric losses of the ferrite/garnet and ceramic dielectrics dielectric constant of the ferrite/garnet and ceramic dielectricsdielectric constant of the ferrite/garnet and ceramic dielectrics

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 development Technological 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 methods Elaboration 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 P Invited A.Anna Sztaniszlav, M. Balla, M. Farkas-Jahnke Solid State Reactions in the Fe 2 O 3 -CaCO 3 -In 2 O 3 System Journal opf Materials Science 25. (1990) p 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 (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 (2000)