PTCR陶瓷化学沉积镍电极界面结构及特性的研究

Research on the Nanosize Interface Structure and Properties of Electroless Nickel Electrode on PTCR Ceramics

通过伏安特性和阻温特性测试研究了不同沉积条件下所得化学沉积镍电极BaTiO3基半导瓷热敏电阻元件的电性能,利用扫描电镜、透射电镜和X-衍射等现代分析手段,重点分析了在不同工艺条件下得到的化学镀镍电极与PTCR陶瓷之间的纳米界面结构及其特性,得到良好的欧姆接触化学镀镍电极的实验参数。

The electrical behavior of BaTiO_3-based PTCR thermistors with Ni-P/Ag electrodes was investigated by I-V and R-T characteristics of them. The contact resistance and the total resistance of the PTC increased with decreasing thickness of the Ni-P layer at constant Ag top layer. The Ag formed a blocking contact to the ceramic in contrast to the Ni-P which showed a good ohmic behavior. Supplementary scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses had been used to study the structure of the electrode interface and the structure of the layers. X-ray diffraction (XRD) analysis indicated that the formation of Ni-P alloy improved the ohmic contact between Ni-P electrodes and BaTiO_3 PTCR ceramics.