The effect of small changes in sintering temperature on microstructure, electrical properties, dielectric characteristics, and degradation behavior of V-Mn-Nb-Gd co-doped zinc oxide ceramics was investigated. With the...The effect of small changes in sintering temperature on microstructure, electrical properties, dielectric characteristics, and degradation behavior of V-Mn-Nb-Gd co-doped zinc oxide ceramics was investigated. With the increase of sintering temperature, the densities of the sintered pellets decreased from 5.54 to 5.42 g/cm3 and the average grain size increased from 4.1 to 11.7 μm. The breakdown field(E1 m A) decreased noticeably from 7138 to 920 V/cm with the increase of sintering temperature. The varistor ceramics sintered at 900 ℃ exhibited excellent nonohmic properties, which were 66 for the nonohmic coefficient and 77 μA/cm2 for the leakage current density. Concerning stability, the varistors sintered at 900 ℃ exhibited the strongest accelerated degradation characteristics, with ΔE1 mA =-9.2% for DC accelerated degradation stress of 0.85 E1 m A at 85 °C for 24 h.展开更多
We present in this paper a new method,based on measurements of conventional direct current-voltage(I-V) characteristics and transient voltage-time(V-t) characteristics during the discharge process,for determining capa...We present in this paper a new method,based on measurements of conventional direct current-voltage(I-V) characteristics and transient voltage-time(V-t) characteristics during the discharge process,for determining capacitance-voltage(C-V) characteris-tics of organic semiconductor devices.Derivatives of I-V and V-t,dI/dV and dV/dt,are related with C by a simple formula C=-V(dI/dV)/(dV/dt)The validity of the method is confirmed by experimental data measured from a set of single-organic-layer devices with different layer thicknesses.展开更多
文摘The effect of small changes in sintering temperature on microstructure, electrical properties, dielectric characteristics, and degradation behavior of V-Mn-Nb-Gd co-doped zinc oxide ceramics was investigated. With the increase of sintering temperature, the densities of the sintered pellets decreased from 5.54 to 5.42 g/cm3 and the average grain size increased from 4.1 to 11.7 μm. The breakdown field(E1 m A) decreased noticeably from 7138 to 920 V/cm with the increase of sintering temperature. The varistor ceramics sintered at 900 ℃ exhibited excellent nonohmic properties, which were 66 for the nonohmic coefficient and 77 μA/cm2 for the leakage current density. Concerning stability, the varistors sintered at 900 ℃ exhibited the strongest accelerated degradation characteristics, with ΔE1 mA =-9.2% for DC accelerated degradation stress of 0.85 E1 m A at 85 °C for 24 h.
基金supported by the Shanghai Committee of Science and Technology, China (Grant No. 08Jc1402300)
文摘We present in this paper a new method,based on measurements of conventional direct current-voltage(I-V) characteristics and transient voltage-time(V-t) characteristics during the discharge process,for determining capacitance-voltage(C-V) characteris-tics of organic semiconductor devices.Derivatives of I-V and V-t,dI/dV and dV/dt,are related with C by a simple formula C=-V(dI/dV)/(dV/dt)The validity of the method is confirmed by experimental data measured from a set of single-organic-layer devices with different layer thicknesses.