Li-Nb-Ti-based microwave dielectric ceramic material

Abstract

The present invention discloses a low-temperature sintering moderate permittivity Li-Nb-Ti-based microwave dielectric ceramic material and a preparation method thereof. The material is prepared from a lithium niobium titanium-based material and a glass burning reducing agent accounting for 0.5 to 6.0 wt% of a principal crystalline phase by solid-phase reaction, the lithium niobium titanium based material composition is LiaNbbTicO3, wherein a is greater than 1.2 and less than 1.4, b is greater than 0.3 and less than 0.4, and c is greater than0.5 and less than 0.7. The glass burning reducing agent is prepared from the raw materials comprising lithium carbonate (Li2CO3), zinc oxide (ZnO), aluminum oxide (Al2O3), silicon dioxide (SiO2), diboron trioxide (B2O3) and a trace additive component. The low-temperature sintering LTCC (low temperature co-fired ceramic) microwave dielectric ceramic prepared by the method is good in sintering at 850-900 DEG C, high in moderate dielectric constant (epsilon r of 45 to 50) and quality factor Q * f (greater than or equal to 8000GHz), can be used in manufacturing of low-temperature co-fired ceramic systems (LTCC), multilayer dielectric resonators, microwave antennas, filters and other microwave devices, and has a great use value in the industry.

Description

technical field [0001] The invention belongs to the field of dielectric ceramics, in particular to composite microwave dielectric ceramic materials. Background technique [0002] Microwave dielectric ceramics refer to ceramics that are used as dielectric materials in microwave frequency band (mainly UHF, SHF frequency band) circuits and perform one or more functions. They are widely used as resonators, filters, and dielectric substrates in modern communications. Chips, dielectric waveguide circuits and other components are the key basic materials of modern communication technology. They have very important applications in portable mobile phones, TV satellite receivers, and military radars. In the process of miniaturization and integration of modern communication tools Zhongzheng is playing an increasingly important role. [0003] Dielectric ceramics used in the microwave frequency band should meet the requirements: (1) a suitable dielectric constant to facilitate the miniat...

AI Technical Summary

Problems solved by technology

However, the sintering temperature of undoped LNT ceramics is relatively high (1100°C), and it cannot be directly co-fired with low melting point metals such as Ag and Cu.

In order to reduce the sintering temperature, one of the traditional methods is to add low melting point oxides, such as B 2 o 3 and V 2 o 5 , while the free B 2 o 3 and V 2 o 5 In the late casting process, the viscosity of the slurry is too high and unstable, which greatly limits the development of LNT materials and microwave multilayer devices.

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