Material & Process Development Center, Corporate R&D Group, Technology HQ, TDK Corporation, Narita, Japan.
IEEE Trans Ultrason Ferroelectr Freq Control. 2012 Sep;59(9):1996-2003. doi: 10.1109/TUFFC.2012.2419.
The valences of manganese and vanadium oxides in multi-layer ceramic capacitors (MLCCs), sintered under a reducing atmosphere, were investigated using electron paramagnetic resonance; insulation resistance degradation was analyzed using impedance spectroscopy in highly accelerated lifetime tests to clarify the influences of manganese and vanadium on both the electrical properties and microstructure of MLCCs. The Mn(2+) was stable in the reducing-atmospheresintered MLCCs and formed a grain boundary. Vanadium mitigated insulation resistance degradation and increased the reliability of the MLCCs. Although V4+ was detected in MLCCs that had 0.20 mol% and 0.30 mol% of added vanadium, the electrical properties were dependent upon other ions, e.g., V(3+) or V(5+). All vanadium ions except for V(4+) decreased the insulation resistance of ceramic/electrode interface. This is because vanadium reduces electric field concentration at the ceramic/ electrode interface and delays the onset of oxygen vacancy migration in the early stages of a highly accelerated lifetime test.
采用电子顺磁共振研究了在还原气氛下烧结的多层陶瓷电容器（MLCC）中锰和钒氧化物的价态；通过在高加速寿命试验中的阻抗谱分析了绝缘电阻退化，以阐明锰和钒对 MLCC 的电性能和微观结构的影响。在还原气氛下烧结的 MLCC 中，Mn(2+) 稳定并形成晶界。钒减轻了绝缘电阻退化，提高了 MLCC 的可靠性。尽管在添加了 0.20 摩尔%和 0.30 摩尔%的钒的 MLCC 中检测到了 V4+，但其电性能取决于其他离子，例如 V(3+) 或 V(5+)。除了 V(4+)之外的所有钒离子都降低了陶瓷/电极界面的绝缘电阻。这是因为钒降低了陶瓷/电极界面处的电场集中，并在高加速寿命试验的早期阶段延迟了氧空位迁移的开始。
