Effect of Silver Addition on the Dielectric Properties of Barium Titanate‐Based X7R Ceramics

Abstract

Different amounts of silver (0.5–10 wt%) have been mixed with EIA X7R‐type ceramic powders based on barium titanate. The XRD analysis indicated that no phases other than BaTiO3 and silver were present in the doped ceramics; it further suggested that no reaction took place between BaTiO3 and silver during calcination and sintering. SEM observation showed that the silver particles presented island distribution in the BaTiO3 ceramic matrix. The densification and dielectric properties of the silver‐doped ceramics in disk form were investigated. A large amount of silver addition (>1 wt%) was found to improve the sintered density and dielectric properties. The temperature coefficient of capacitors of the ceramics doped with 10 wt% silver still met the X7R characteristics, and the dielectric constant of the ceramics at room temperature was >6000, which is the highest dielectric constant in the BaTiO3‐based X7R system.

Dielectric Degradation and Microstructures of Heterogeneous Interfaces in Cofired Multilayer Ceramic Capacitors

“…As Ag is a noble electrode, it was not oxidized during the sintering process, so it was impossible for Ag atoms to form ionic bonds either by entering the A sites of the perovskite structure, or by diffusing into the glass flux. The present work supports the assertion that silver diffusion into the dielectrics is negligible during the cofiring process [7][8][9].…”

“…The effect of silver on the sintering was a result of prohibition of grain growth by the silver inclusions. Silver inclusions also increased the dielectric constant, but decreased the insulation resistance and breakdown voltage [7][8][9].…”

Fabrication of BaTiO3/Ag composites using uniform Ag-deposited BaTiO3 particles

“…12) Chen et al reported that the addition of Ag more than 1 wt% improves the BaTiO3 sintering properties. 9) Therefore, in this case, the addition of 5 wt% Ag must improve the sinterability of BaTiO3 particles and strengthen the grain boundary. In addition, the Ag grains in the composites were small and the composite prepared using SPS showed the highest hardness.…”

Characterisation and Modelling of Barium Titanate-Silver Composites

“…This increase could be due to the silver particles acting as inter-electrodes within the barium titanate and FIGURE 3 Graphs showing (a) increasing permittivity with silver particle content (measured at 1 kHz) and (b) permittivity of a reference 30% resistor-70% capacitor random network with random components replaced with 1 µ resistors to simulate conductive defects (Average of 256 simulations at 1 kHz with a 3D matrix of 16 component side length). increasing the local electric field [4]. Additional electrical characterisation (polarisation-field) was conducted and will be reported elsewhere.…”

“…Previous research on the barium titanate-silicon carbide system indicates that semi-conducting reaction phases are formed which suggests that any benefits in mechanical properties are at the expense of electrical properties [3]. Improvements in specific properties, such as mechanical strength and toughness, have been observed by other researchers on addition of conductive particles into electroceramics [4]. In this work, silver particles have been added to barium titanate.…”