Effects of ZnO–xV2O5 substitution on the microstructure and microwave dielectric properties of ZnNb2O6 ceramics

Abstract

The ZnO-xV 2 O 5 substituted ZnNb 2 O 6 ceramics with chemical formula Zn(Nb 0.9 V x ) 2 O 5.5+5x (0<x≤0.10) were prepared by solid-state reaction route. The densities, microstructures and microwave dielectric properties were investigated according to the different substitution amount of V 2 O 5 and sintering temperature. A small amount of substitution of ZnO-xV 2 O 5 was effective to lower sintering temperature of ZnNb 2 O 6 ceramics from 1,150°C to 900°C. The V 2 O 5 substitution led to growth of rod-like grains with the help of liquid phase formed from ZnO and V 2 O 5 . The dielectric properties depended largely on the amount of V 2 O 5 substitution and sintering temperature. The dense ceramics with x=0.05 were obtained at 950°C, which had excellent dielectric properties: e r =24, Q×f=72,800 GHz and τ f =−63.5 ppm/°C. The interface analysis for cofired multilayer composites composed of the present LTCC and metal Ag demonstrated good co-firing chemical compatibility at co-sintering temperature.

Effect of Sintering Temperature on CuO Doped Barium Zinc Tantalate (BZT) Dielectric Properties

“…The results further reveal that a small amount of CuO gives an effect on the size reduction, acts as a good grain growth inhibitor and leads to the grains being well-formed. The decreasing grain size with the increasing x is associated with lower grain growth rate caused by the slow diffusion of the Cu 2+ due to similar ionic radius with Ta 5+ [12].The size distribution of the doped BZT ceramics was predominantly determined by the amount of the CuO addition. The increasing amount of mol.% of CuO caused the grains to turn from circle to rodlike grains and the grain size grew larger.…”

Investigation on the effect of sintering under oxygen atmosphere on microstructure and microwave dielectric properties of ZnNb 2 O 6 ceramics

“…This can be explained by lower ZnO loss under oxygen atmosphere. The mechanism for loss of ZnO is as follows [11] …”

“…The variation of ε r values with zinc content was not considerable and ranged between 22 and 24. Wang et al [11] investigated the effect of addition of ZnO and V 2 O 5 on the microstructure and microwave dielectric properties of ZN ceramics as chemical formula Zn(Nb 0.9 V x ) 2 O 5.5+5 x . It was shown that for 0 < x ≤ 0.1 sintering temperature was reduced from 1150°C to about 900–950°C.…”

Crystallization behavior and microwave dielectric characteristics of ZnO-(La, Nd)2O3-B2O3-based dielectrics

“…The LTCC technology offers the possibility of the monolithic multilayer structures with buried passive components as a key development for integrated electronic components including IC packaging radar and antennas [1][2][3]. As an LTCC substrate material, dielectric ceramics have been investigated to meet the target characteristics such as low dielectric constant and high quality factor [4][5][6]. Zero TCF has been additionally required to get temperature stability against a frequency drift.…”