L.A. Bliznyuk1, N.V. Lyubetsky2, A.K. Letko3, T.P. Petrochenko4, V.I. Kasko5

1–4 Scientific and Practical Center of the National Academy of Sciences of Belarus
for Materials Science (Minsk, Republic of Belarus)
4 tanya-petr@physics.by

Ferroelectric ceramics of barium titanate and its solid solutions have found wide applications in technology, while compositions of a binary system with strontium titanate are most in demand. Electrically controlled components based on the barium titanate – strontium titanate ferroelectric ceramics are widely used in accelerator technology and the use of these materials is relevant at the present time.

In the microwave range, composites based on the solid solution system barium titanate – strontium titanate ВаxSr1–xTiO3 (BST). Ferroelectric samples based on ВаxSrx–1TiO3 compound, where x = 0; 0.1; 0.3; 0.5; 0.7 were obtained using a conventional ceramic technology.

The temperature dependences of the electrical properties of bulk ceramic samples based on ferroelectric composites were received in the temperature range 100°C to 350°C at a frequency of 1 kHz. It has been established that dielectric parameters significantly depend on the BaTiO3 content in BST compositions.

To carry out a research in the frequency range from 0.1 to 8.5 GHz, an experimental setup was manufactured for measuring the electrical properties of ferroelectric materials based on an Agilent E5071C vector analyzer and a microstrip line. To conduct temperature studies, a microstrip line with a controlled sample was placed in a heat, cold and moisture chamber of the Bench-Top SU-261 series, in which it has been heated up to 60°C.

The amplitude-frequency characteristics of the transmission coefficient (S21) of samples when heated from 20 °C to 60°C with an interval of 10 degrees were studied. The resonant frequency and quality factor of the resonator have been determined from the amplitude-frequency characteristic. Based on the value of the resonant frequency and the geometric dimensions of the sample, the dielectric constant of the sample material was calculated. It has been shown that with increasing barium titanate content (x = 0.1–0.3), the dielectric constant of the samples under study increases, and the resonant frequency shifts to lower frequencies. For samples with a barium titanate content of 50% and higher (x≥0.5), there are no resonance dependences and strong absorption of electromagnetic waves is observed. It has been established that with increasing temperature, the resonant frequency of composite material samples shifts to higher frequencies. Frequency dispersion of the dielectric constant is observed, which indicates the relaxor properties of the ceramic samples under study.

Experimental investigations were carried out using a microwave strip line, a coaxial measuring cell and a capacitive converter; this made it possible to measure the dielectric constant of materials with values of more than several hundred in the microwave range and significantly reduce the control time when conducting thermal studies. It was shown that with a change in temperature, the electrophysical properties of the samples change significantly, which can be used in various systems and devices to change the reflection coefficient and phase of the electromagnetic wave.

Bliznyuk L.A., Lyubetsky N.V., Letko A.K., Petrochenko T.P., Kasko V.I. Properties of ferroelectric composites in the microwave range. Nanotechnology: development and applications – XXI century. 2024. V. 16. № 2. P. 40–47. DOI: https://doi.org/10.18127/ j22250980-202402-04 (in Russian)

1. Hasbulatov S.V., Sadykov H.A., Polovinkin B.S., Verbenko I.A., Shilkina L.A., Dudkina S.I., Andryushina I.N., Reznichenko L.A., Nagaenko A.V. Optimizaciya uslovij polucheniya funkcional'nyh keramicheskih materialov s uchastiem titanata bariya. Konstrukcii iz kompozicionnyh materialov. 2016. № 4. S. 27–34 (in Russian).
2. Sidorkin A.S., Nesterenko L.P. Svojstva sloistyh struktur na osnove titanata bariya v slabyh i sil'nyh elektricheskih polyah. Ohrana, bezopasnost', svyaz'. 2019. № 4–3. S. 48–57 (in Russian).
3. Gridnev S.A., Kalinin Yu.E., Makagonov V.A., Pankov S.Yu. Elektricheskie svojstva poluprovodnikovyh keramik na osnove titanata bariya. Vestnik Voronezhskogo gosudarstvennogo tekhnicheskogo universiteta. 2012. T. 8. № 11. S. 57–61 (in Russian).
4. Myl'nikov I.L., Burovihin A.P., Dedyk A.I., Semenov A.A., Pavlova Yu.V., Belyavskij P.Yu., Antonova A.S., Ershov A.A. Izmereniya temperaturnyh zavisimostej emkosti kondensatornyh struktur na osnove BTO i BST v rezhime «ohlazhdenie-nagrev». Sb. dokladov XI Vseros. nauch.-tekhn. konfer. «Elektronika i mikroelektronika SVCh». 2022. S. 324–329 (in Russian).
5. Kanarejkin A.D., Shejnman I.A., Al'tmark A.M. Upravlenie chastotnym spektrom v kil'vaternyh volnovodnyh strukturah. Pis'ma v ZhTF. 2002. T. 28(21). S. 75–80 (in Russian).
6. Al'tmark A.M., Kanarejkin A.D., Shejnman I.A. Upravlyaemaya uskoritel'naya kil'vaternaya struktura s dielektricheskim zapolneniem. Pis'ma v ZhTF. 2005. T. 75(1). S. 89–97 (in Russian).
7. Nenasheva E.A., Kanarejkin A.D., Dedyk A.I., Pavlova Yu.V. Elektricheski upravlyaemye komponenty na osnove keramiki BST−Mg dlya primeneniya v uskoritel'noj tekhnike. Fizika tverdogo tela. 2009. T. 51. Vyp. 8. S. 1468–1471 (in Russian).
8. Platonov R.A., Altynnikov A.G., Yastrebov A.V., Mihajlov A.L., Kozyrev A.B. Elektricheski upravlyaemaya struktura s periodicheskim izmeneniem volnovogo soprotivleniya dlya otkloneniya osnovnogo lucha vysokonapravlennogo izluchatelya millimetrovogo diapazona dlin voln. Izv. vuzov Rossii. Ser.: Radioelektronika. 2016. № 3. S. 67–70 (in Russian).
9. Lubetsky N.V. Modulator of polarization for quasioptical transmission line. MSMW 2001 Symposium Proceedings. Kharkov. Ukraine. June 4–9. 2001. R. 630–632.
10. Bliznyuk L.A., Lyubeckij N.V., Petrochenko T.P., Letko A.K., Kasko V.I. Svojstva ob"emnyh segnetoelektricheskih materialov v mikrovolnovom diapazone. Sb. dokladov H MNK «Aktual'nyj problemy fiziki tverdogo tela». Minsk. 22–26 maya 2023 g. S. 283–286 (in Russian).
11. Karonis G.J., Kaklamani D.I., Uzunoglu N.K. Accurate Analysis of a Cylindrical Dielectric Resonator Mounted on a Grounded Dielectric Substrate. Progress in Electromagnetics Research. 1999. P. 187–219. ceta.mit.edu/PIER/pier23/9811252. K. Kaklamani.U.pdf.