Microwave Dielectric Property of Porous Silicon Nitride Ceramics


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This paper presents the microwave dielectric property of porous silicon nitride ceramics at a frequency of 9360 MHz, which were fabricated by the nitridation of silicon powder. The porous ceramics with different volume fraction of porosity from 18.6% to 56.2% were produced by adding different amount of the pore-forming agent into the initial silicon powder. Microstructural analysis revealed a dense matrix containing large pores and cavities with needle-shaped and flaky β-Si3N4 grains distributing in it. The results showed that the dielectric constant of the ceramics reduces with the porosity increases. With the addition of α-Si3N4 powder in the raw silicon powder, the nitridation rate is raised, and the dielectric constant and the dielectric loss of the ceramics decrease notablely.



Key Engineering Materials (Volumes 336-338)

Edited by:

Wei Pan and Jianghong Gong




J. Q. Li et al., "Microwave Dielectric Property of Porous Silicon Nitride Ceramics", Key Engineering Materials, Vols. 336-338, pp. 307-309, 2007

Online since:

April 2007




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