Electrical Resistivity of AlN-hBN-TiB2 Ceramic Composite

DOI: 10.62564/M4-IF2339

Vadym Omelianenko, Igor Fesenko, Oksana Kaidash, Nina Sergienko

V. Bakul Institute for Superhard Materials of the National Academy of Sciences of Ukraine


Dielectric matrix ceramic composites based on high thermal conductivity AlN are important for engineering of new electronic devices with lower operation temperature. Composites of AlN dielectric matrix with electroconductive inclusions of TiB2 have been prepared and investigated with the aim to establish their electrical resistivity for possible applications. The ceramic composites AlN–hBN–TiB2 have been prepared by hot pressing (T=1950 °С, P=30 MPa) with TiB2 content from 45 to 66 wt.%. The four-probe electrical resistivity measurements of as-obtained specimen at room temperature showed correspondingly values between 1.0•10–5 and 0.2•10–5 Ohm•m. The observed relatively small decrease of electrical resistivity of the hot-pressed AlN–hBN–TiB2 system composite for increasing conductive phase content by 21 wt.%, and when conductive phase content is higher than a percolation threshold may testify in favor of a tunnel character of charge transfer, discussed in [1]. Addition of hBN under mixing of the starting powder system may form an additional dielectric layer at the surface of the conductive particles (TiB2). Thus a tunnel mechanism of charge transfer in the hot-pressedAlN–hBN–TiB2 ceramic composites may dominate in a wide region of concentrations including the percolation threshold.

Keywords
Composite, aluminum nitride, matrix

Acknowledgments
Not provided

References
[1] Baibara O., Radchenko M., Ievtushenko A. et al. Features and theoretical analysis of electric and thermoelectric properties of Co/Al2O3, Co/SiO2 and Co/TiO2 ferromagnetic nanocomposites in the low-temperature region. HighMatTech–2023, October 2-6, 2023, Kyiv, Ukraine, Book of Abstracts, P. 34.