Temperature Stability Of Nickel Electrode Mlcc Information

A novel nano-doping process was introduced for the preparation of submicron BaTiO₃-based ultrafine nonreducible dielectrics for Multilayer Ceramic Capacitance in this thesis. The nano-dopant obtained by water-based sol-gel method was well dispersive and active. Effect of pH, concentration and temperature of the solution on the formation of sol-gel was investigated, and the characteristics of xerogel and powder were analyzed by TG-DTA, XRD and TEM. The particle sizes of BaTiO₃ synthesized from hydrothermal method dependence of dielectric properties were studied. A model of the nano-doping mechanism was developed based on comparing conventional process with nano-doping process. It indicated that due to the special nano-effect, modification effect of foreign atom was improved effectively and the microstructure and macro dielectric characteristics of so acquired ceramics were improved consequently. The effects of the rare earth ions, alkaline earth ions and transition metal ions in the nano-dopant on the properties of BaTiO3-based dielectrics were discussed. The relation between the formation mechanism of core-shell structure and the chemical ingredient as well as electrical properties of the ceramic were systematically researched. High performance dielectrics were acquired, with permittivity more than 2500, dielectric loss lower than 1.0% and average grain size about 0.3μm, which satisfy the requirement of EIA X7R specifications. The X7R Ni-MLCC of EIA0603 size, with above 150 dielectric layers of below 7μm thickness, was fabricated using this new ultrafine dielectrics. The dielectric behaviors reach the level as follows: C=13.156nF, K=3292, DF=1.55%, V_b=1.5kV, IR=10¹⁰Ω·cm. Strength and bending resistance test, welding heat test and highly accelerated life test (HALT) were retested up to grade.