The reliability of MLCC by the additives associated with the grain size and sintering condition
The reliability of mulitilayer ceramic capacitors (MLCCS) with Ni internal electrodes has been studied from the viewpoint of partial oxygen pressure (Po2) during firing. It is shown that the load-life time of the insulation resistance (IR) was prolonged by firing under low Po2, annealing after firing, and the addition of dopants. It is also shown that the generation of oxygen vacancies led to the degradation of IR. Annealing treatment for the oxidation of the dielectric body accelerates the dielectric aging of MLCC. It is found that the appropriate control of the Po2 during firing can improve the reliability of MLCCs with Ni electrodes to a level as high as that of MLCCs with precious metal electrodes. Thus, we have developed an MLCC with Ni electrodes that features high reliability and a capacitance of 2.2 muF for the X7R characteristic.