Microwave Dielectric Properties and Low Temperature Sintering of Sm₂Si₂O₇ Ceramic for Substrate Applications

Abstract

The Sm 2 Si 2 O 7 ceramics were synthesized by solid-state ceramic route. The calcination and sintering temperature of Sm 2 Si 2 O 7 were optimized for the best properties. The crystal structure and microstructure of the ceramic were studied by X-ray diffraction and scanning electron microscopic methods. The low frequency dielectric properties were studied at 1 MHz. The dielectric properties of the ceramic were measured in the microwave frequency range by the cavity perturbation method. Sm 2 Si 2 O 7 has e r 5 12.5, tan d 5 8 Â 10 À4 , and t e 5 163 ppm/1C at 1 MHz and a relative permittivity of 10 and tan d of 6 Â 10 À3 in the microwave frequency range. The effect of addition of various low loss glasses such as 50ZnO-50B 2 O 3 (ZB), 2 (LBS) and 20Li 2 O-20MgO-20ZnO-20B 2 O 3 -20SiO 2 (LMZBS) on the microwave dielectric properties of Sm 2 Si 2 O 7 was also investigated. It was found that the addition of 15 wt% LBS glass reduced the sintering temperature from 13751C to 9751C with e r 5 9.89 and tan d 5 0.024. Fifteen weight percent LMZBS glass ceramic decreased the sintering temperature to 9501C with e r 5 9.09 and tan d 5 0.009. The results show that Sm 2 Si 2 O 7 mixed with suitable amounts of selected glasses is a promising material for microwave substrate applications.

Effect of Glass Addition on the Microwave Dielectric Properties of CaMgSi2O6 Ceramics

“…The effect of addition of different glasses such as B, BBS, MBS, ZBS, PBS, LBS, and LMZBS on the sintering temperature of CMS was investigated. The physical and dielectric properties of these glasses have been reported earlier 29,37–39 . The variation of sintering temperature of CMS–glass composites as a function of different wt% of added glasses is shown in Fig.…”

Crystal Structure and Microwave Dielectric Properties of LiRE9(SiO4)6O2 Ceramics (RE = La,Pr,Nd,Sm,Eu,Gd, and Er)

“…reported the microwave dielectric properties of forsterite ceramics with a high quality factor and low relative permittivity. Several other silicates with excellent microwave dielectric properties have been recently reported in the literature; however, investigations of the microwave dielectric properties of new silicates are still continuing in search for materials with balanced properties for substrate applications. The relationship between structural parameters and microwave dielectric properties need to be explored to control their properties.…”

Effect of lithium-based glass addition on the microwave dielectric properties of Ca[(Li1/3Nb2/3)1−xTix]O3−δ ceramics for LTCC applications

“…However, multi-component glasses are more effective than single component glasses to reduce the sintering temperature of the ceramics without much degradation of the microwave dielectric properties [23]. In order to develop lithium-based complex perovskites for LTCC application, we have selected low loss lithium-based boron-rich multi-component glasses such as lithium borosilicate (35.1Li 2 O-31.7B 2 O 3 -33.2SiO 2 ) (LBS) [24] and lithium magnesium zinc borosilicate (20Li 2 O-20MgO-20ZnO-20B 2 O 3 -20SiO 2 ) (LMZBS) [25] glasses. Few attempts have been made to lower the sintering temperature of the CLNT ceramics by low melting glasses such as B 2 O 3 , B 2 O 3 -Bi 2 O 3 , ZnO-B 2 O 3 -SiO 2 (ZBS) and ZBS-LiF [26][27][28][29][30][31].…”