Tape Casting and Dielectric Properties of Zn₂Te₃O₈‐Based Ceramics with an Ultra‐Low Sintering Temperature

Abstract

The suitability of dielectric ceramics made of zinc tellurate (Zn2Te3O8) and titanium dioxide (TiO2) with an ultra‐low sintering temperature (650°C) for tape casting and thus for the multimodule technique with Al electrodes was investigated. The properties of the tape before and after sintering as well as the amount of organic additives for the casting process and a thermal analysis of the tape up to 1000°C are reported. In addition, electrodes on a multilayer module made on stacked tapes were prepared using Al paste and postfiring, followed by relative permittivity and loss tangent measurements to verify the electrical performance of the whole structure. The dielectric properties of the stacked module without any electrodes were also measured. The results show that the composition is well suited for the tape process but extra care should be taken especially with the proper sintering temperature for optimized electrical performance.

Casting and characterization of LiMgPO4 glass free LTCC tape for microwave applications

“…4 In the present study, wt.% of both the binder and Type II plasticizer are large (Table 2) compared to many of the previously reported tape casting slurry compositions. 4,10,25,26 Fig. 6 shows the viscosity of the final slurry as a function of shear rate.…”

“…6 Some glass free ceramics have also been reported for LTCC applications. [7][8][9][10][11][12][13][14][15] In our previous work we reported the microwave dielectric properties of LiMgPO 4 ceramic which can be sintered at 950 • C without any glass addition. 14 The LiMgPO 4 ceramic has good microwave dielectric properties: ε r = 6.6, Q u × f = 79,100 GHz and τ f = −55 ppm/ • C. The ceramic is also chemically compatible with Ag.…”

Ultra-low sintering temperature ceramics for LTCC applications: a review

“…Non-aqueous systems offer the advantages of fast and easy drying of the cast tapes [59]. In 2009, Honkamo et al firstly reported the dielectric properties of Zn 2 Te 3 O 8 -based ceramics fabricated by tape casting method [59]. The Zn 2 Te 3 O 8 powder with 4 wt% TiO 2 (ZTT) was prepared by a solid-stated ceramic route.…”

“…In aqueous route, water is used as the solvent for slurry preparation and in non-aqueous route some organic solvent will be used. Non-aqueous systems offer the advantages of fast and easy drying of the cast tapes [59]. In 2009, Honkamo et al firstly reported the dielectric properties of Zn 2 Te 3 O 8 -based ceramics fabricated by tape casting method [59].…”

“…Amount of dispersant and amount of binder as a function of specific area (SSA) for several tape-casting slurries Ref [59]. …”