TY - JOUR
T1 - Raman spectroscopy evaluation of oxygen vacancy migration by electrical field in multilayer ceramic capacitors
AU - Nishida, Ken
AU - Kishi, Hiroshi
AU - Osada, Minoru
AU - Funakubo, Hiroshi
AU - Nishide, Masamichi
AU - Takeuchi, Hironari
AU - Katoda, Takashi
AU - Yamamoto, Takashi
PY - 2009
Y1 - 2009
N2 - Raman spectroscopy is used to evaluate migration behavior of oxygen vacancies in BaTiO3-based multilayer ceramic capacitors with Ni internal electrodes (Ni-MLCCs) before and after a highly accelerated life test (HALT). The B1 phonon mode of BaTiO3 that is associated with oxygen vibration was hardened and broadened near the Ni electrodes before HALT. However, the hardening and broadening of the B1 mode were observed near the cathodes after HALT. It is considered that the oxygen vacancies were localized near the Ni electrodes before HALT and they electromigrated toward the cathode because they have the positive charges. These results show that oxygen vacancies migrated and accumulated near the cathode under a dc bias and caused insulation resistance degradation in MLCCs. In addition, Raman spectroscopy is a powerful tool for investigation of structural defect distribution including oxygen vacancies with a relatively high spatial resolution.
AB - Raman spectroscopy is used to evaluate migration behavior of oxygen vacancies in BaTiO3-based multilayer ceramic capacitors with Ni internal electrodes (Ni-MLCCs) before and after a highly accelerated life test (HALT). The B1 phonon mode of BaTiO3 that is associated with oxygen vibration was hardened and broadened near the Ni electrodes before HALT. However, the hardening and broadening of the B1 mode were observed near the cathodes after HALT. It is considered that the oxygen vacancies were localized near the Ni electrodes before HALT and they electromigrated toward the cathode because they have the positive charges. These results show that oxygen vacancies migrated and accumulated near the cathode under a dc bias and caused insulation resistance degradation in MLCCs. In addition, Raman spectroscopy is a powerful tool for investigation of structural defect distribution including oxygen vacancies with a relatively high spatial resolution.
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U2 - 10.1143/JJAP.48.09KF11
DO - 10.1143/JJAP.48.09KF11
M3 - Article
AN - SCOPUS:77952701045
SN - 0021-4922
VL - 48
JO - Japanese Journal of Applied Physics
JF - Japanese Journal of Applied Physics
IS - 9 Part 2
ER -