TY - JOUR
T1 - Degradation of potential barriers in ZnO-based chip varistors due to electrostatic discharge
AU - Hirose, Sakyo
AU - Niimi, Hideaki
AU - Kageyama, Keisuke
AU - Ieki, Hideharu
AU - Omata, Takahisa
AU - Otsuka-Yao-Matsuo, Shinya
PY - 2012/8
Y1 - 2012/8
N2 - Degradation of potential barriers in ZnO-based varistors due to the electrostatic discharge (ESD) was investigated using scanning probe microanalysis and capacitance-time and isothermal capacitance transient spectroscopies. Pr 6O 11-ZnO (Pr-ZnO) varistors exhibit excellent ESD withstand capability compared with Bi 2O 3-ZnO (Bi-ZnO) varistors. After the application of ESD, asymmetrically degraded double Schottky barriers were observed in both Pr-ZnO and Bi-ZnO varistors, and the Schottky barrier in Bi-ZnO was found to be destroyed. The potential barriers of both types of varistors can respond to an ESD pulse, whose rise time is ∼1 ns, but after application of the ESD pulse, the Bi-ZnO varistor takes more time to recover its initial capacitance than does the Pr-ZnO varistor. Such difference in the transient behaviors of potential barriers is attributed to differences in the energy and distribution of interfacial states of Pr-ZnO and Bi-ZnO varistors. Experimental results clearly indicated a strong correlation between the transient behaviors of potential barriers and the ESD withstand capabilities of ZnO-based varistors.
AB - Degradation of potential barriers in ZnO-based varistors due to the electrostatic discharge (ESD) was investigated using scanning probe microanalysis and capacitance-time and isothermal capacitance transient spectroscopies. Pr 6O 11-ZnO (Pr-ZnO) varistors exhibit excellent ESD withstand capability compared with Bi 2O 3-ZnO (Bi-ZnO) varistors. After the application of ESD, asymmetrically degraded double Schottky barriers were observed in both Pr-ZnO and Bi-ZnO varistors, and the Schottky barrier in Bi-ZnO was found to be destroyed. The potential barriers of both types of varistors can respond to an ESD pulse, whose rise time is ∼1 ns, but after application of the ESD pulse, the Bi-ZnO varistor takes more time to recover its initial capacitance than does the Pr-ZnO varistor. Such difference in the transient behaviors of potential barriers is attributed to differences in the energy and distribution of interfacial states of Pr-ZnO and Bi-ZnO varistors. Experimental results clearly indicated a strong correlation between the transient behaviors of potential barriers and the ESD withstand capabilities of ZnO-based varistors.
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U2 - 10.1063/1.4742987
DO - 10.1063/1.4742987
M3 - Article
AN - SCOPUS:84865257013
VL - 112
JO - Journal of Applied Physics
JF - Journal of Applied Physics
SN - 0021-8979
IS - 3
M1 - 033707
ER -