DIELECTRIC LOSS OF Si2N2O AND THE INFLUENCE OF Li ON ITS PROPERTIES

Yong Yang; Ming He; Ting Zhang; Meng-qiang Wu

doi:10.17222/mit.2021.334

Yong Yang Department of Biomedical Engineering, School of Big Health and Intelligent Engineering, Chengdu Medical College, Chengdu 610500, China
Ming He Electronic Engineering Institute, Chengdu Technological University, Chengdu, China
Ting Zhang Department of Biomedical Engineering, School of Big Health and Intelligent Engineering, Chengdu Medical College, Chengdu 610500, China
Meng-qiang Wu State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, China

DOI: https://doi.org/10.17222/mit.2021.334

Keywords: Si2N2O, dielectric loss, high temperature, Li doping

Abstract

The dielectric losses of Si₂N₂O, studied theoretically and experimentally up to 1573 K at 10 GHz, demonstrated an increase above 1000 K due to the impurity conduction losses, because of the small Li activation energy. Calculations based on the first-principles theory were performed to obtain the density of states. The optical and elastic properties of Si₂N₂O doped with a 4.8 % molar fraction of Li were modeled using a plane-wave pseudopotential method to investigate the effect of Li incorporation into Si₂N₂O. The polycrystalline static dielectric constants of Si₂N₂O increased after it was doped with Li. We also provided the optical properties of silicon nitride compounds to be used as references. The calculated elastic constants of pure and Li-doped Si₂N₂O indicated that the elastic modulus of the Li-doped Si₂N₂O was smaller than that of the pure Si₂N₂O. Additionally, Li-doped Si₂N₂O crystals were more brittle than the pure forms. Theoretical analyses of the dielectric losses and first-principles calculations emphasized that to consider Li-doped Si₂N₂O materials for applications, the dielectric losses and Li contents should be carefully optimized, since these factors also affect the conductivities of these materials.

References

1. Z. L. Cheng , F.Ye, Y. S. Liu. et al, Mechanical and dielectric properties of porous and
wave-transparent Si3N4-Si3N4 composite ceramics fabricated by 3D printing combined
with chemical vapor infiltration, J Adv Ceram, 8 (2019), No.3, p.399.
2. S. J. Lin, Ye. F , Dong. S. L. et al, Mechanical, dielectric properties and thermal shock
resistance of porous silicon oxynitride ceramics by gas pressure sintering,Materials
Science and Engineering: A, 635 (2015), No.may 21.p.1.
3. Z.H.Zhou, Y.Lan, X.M.Li. et al, Preparation and characterization of silicon oxynitride
nanopowders via thermal explosion synthesis-Gravity separation strategy, Ceramics
International, 47 (2021), No.7. p.9287.
4. Y.J.Li, D.H.Liu,B.Z.Ge. et al, Fabrication of Si2N2O ceramic with silicon kerf waste as
raw material, Ceramics International, 44 (2018), p.5581.
5. L.Y.Hang,W.G.Liu, Xu.J.Q. et al, Effects of various substrate materials on
microstructural and optical properties of amorphous silicon oxynitride thin films
deposited by plasma-enhanced chemical vapor deposition, Thin Solid Films, 709 (2020),
p.138186.
6. A.Nagakubo,S.Tsuboi,Y.Kabe. et al, Zero temperature coefficient of sound velocity in
vitreous silicon oxynitride thin films, Appl Phys Lett, 114 (2019), p.251905.
7. H.Jin, Z.H.Yang, D.L.Cai. et al, 3D printing of porous Si2N2O ceramics based on
strengthened green bodies fabricated via strong colloidal gel, Materials&Design,185
(2020), No.5.p.108220.
8. J.Li, C.Zhang , H.Liu. et al, Structure, morphology, and microwave dielectric properties
of SmAlO3 synthesized by stearic acid route, J Adv Ceram,9 (2020), p.558.
9. F.G.Huang, H.Su,Y.X.Li. et al, Low-temperature sintering and microwave dielectric
properties of CaMg1−xLi2xSi2O6 (x =0-0.3) ceramics, J Adv Ceram, 9 (2020), p.471.
10. Z.L.Lv, H.L.Cui, H.Wang. et al, Vibrational and dielectric properties and ideal strength
of Si2N 2O ceramic from first principles, Ceramics International, 43(2017), p.10006.
11. Q.F.Tong, J.Y.Wang, Z.P.Li.et al, Low-temperature synthesis/densification and properties
of Si2N2O prepared with Li2O additive, J Eur Ceram Soc, 27 (2007), p.4764.
12. E.Li, Z.P.Nie, G.F.Guo et al. Broadband measurements of dielectric properties of
low-loss materials at high temperatures using circular cavity method, Progress In
Electromagnetics Research, 92 (2009), p.103.
13. O.L.Anderson, D.A.Stuart, Calculation of activation energy of ionic conductivity in
silica glasses by classical methods, J Amer Cera Soc, 37 (1954), p.573.
14. T. Zhang , M.Q.Wu, S.R.Zhang. et al, Local electric field investigation of Si2N2O and its
electronic structure, elastic and optical properties, Journal of Alloys and Compounds, 509
(2011), No.5, p.1739.
15. H.Frohlich, Theory of Dielectrics: Dielectric Constant and Dielectric Loss. Oxford
University Press, USA, 1987.
16. W.Y.Ching, S.Y.Ren, Electronic structure of Si2N2O and Ge2N2O crystals, Physical
Review B, 24 (1981), p.5788.
17. M. D. Segall , P. J. DLindan, M. J. Probert. et al, First-principles simulation:ideas,
illustrations and the CASTEP code, J Phys:Condens Matter, 14 (2002), p.2717.
18. B. Liu , J.Y. Wang, F. Z. Li. et al, Effect of interstitial lithium atom on crystal and
electronic structure of silicon oxynitride, J Mater Sci, 44 (2009), No.23, p.6416.
19. W.Y. Ching, Electronic Structure and Bonding of All Crystalline Phases in the
Silica-Yttria-Silicon Nitride Phase Equilibrium Diagram,J Am Ceram Soc, 87 (2004),
p.1996.
20. H.Z.Yao, L.ZOuyang, W.Y.Ching. et al, Ab Initio Calculation of Elastic Constants of
Ceramic Crystals, J Am Ceram Soc, 90 (2007), p.3194.
21. P.Boch, J. C. Glandus, Elastic properties of silicon oxynitride, J Mater Sci, 14 (1979),
p.379.