The mechanism of lifetime improvement through vanadium addition to multilayer ceramic capacitor with nickel electrode

Abstract

One of the methods to improve the lifetime of a multilayer ceramic capacitor with Ni electrode (Ni-MLCC) is vanadium addition. With the addition of vanadium, insulation resistance deteriorates and reliability improves. The resistance elements of the three resistor-capacitor electrical equivalent circuit: dielectric-electrode interface, grain boundary, and grain, all deteriorated. In particular, the interface resistance significantly deteriorated with the increase in vanadium. The experimental results suggest that the high interface resistance is not always necessary to improve reliability of Ni-MLCCs. It is deduced that oxygen vacancy formation is suppressed with vanadium addition from the first principles calculation and the thermally stimulated depolarization current analysis. Therefore, the decrease in oxygen concentration is the main factor for improving reliability with vanadium addition.

Effect of La doping on the suppression of insulation resistance degradation in multi-layer ceramic capacitors

“…TSDC measures the depolarization current during pre-polarization sample heating. Kaneda et al 26) investigated the depolarization currents of Ho-doped BT-MLCCs. They reported that the first depolarization current peak, which was created by the defect dipole disorder, occurred at 150 °C; the second peak, which was created by the drift of oxygen vacancies in the grain, occurred at 200 °C; and the third peak, which was created by the drift of oxygen vacancies across the grain boundary, occurred at 250 °C.…”

“…The thermally stimulated depolarization current (TSDC), which was measured using a TSDC analyzer (TS-FETT; Rigaku Corporation), enabled us to evaluate the space charge behavior of the dielectrics. [26][27][28] Pre-polarization of the Ladoped BSTZ-MLCCs was performed as a function of the electric field (20 kV mm…”

Evaluation of electrical characteristics of locally degraded areas on exfoliated multilayered ceramic capacitors by thermal distribution analysis

“…It was believed that the decrease in insulation resistance is mainly due to electromigration of oxygen vacancies toward the cathode. [6][7][8][9][10][11][12][13][14][15][16][17][18] Several reports have analyzed the characteristics of breakdown states where the ceramic microstructure was severely destructed. 19,20) Once breakdown occurs, it is impossible to analyze dielectric materials in detail.…”