Research On Preparation Technology Of Ceramic Component With Sintering-Free Base Metal Electrode

In recent years,with the popularity and the accelerating upgrade of various electronic products,the market demand is increasing for ceramic capacitors with small size,large capacity,corrosion resistance,high temperature tolerance.Generally,silver is used as the electrode material of capacitors,the expensive material makes the production cost raise.Replacing the noble metal electrode with base metal in electrode has become the inevitable development trend of ceramic capacitor industry.This thesis principally research the ceramic capacitor electrodes made by base metals.In this paper,the base metal copper is selected as the electrode material,and the electroless plating method is used to realize the metallization of the ceramic electrode.A patterned active layer is formed on the ceramic substrate by means of inkjet printing technique,the active layer acts as a catalytic seed layer for subsequent chemical copper deposition.The deposition temperature and time of the electroless plating were optimized by comparing the lustre,microstructure,resistance and adhesion force of the copper layer deposited at different condition.The results indicate excellent copper layers with good appearance lustre,fine copper particles,low square resistance and strong adhesion force were obtained under the optimized deposition temperature of 45~50 ? and deposition time of 20 min.Based on the optimization of the plating process conditions,the influence of the ultrasonic parameters during the process of ultrasonic assist electroless plating on the quality of the coating was discussed.The results indicate that the introduction of ultrasonic assisted deposition in chemical copper deposition can effectively improve the quality of the electrode,because the ultrasonic wave can promote the discharge of hydrogen in the chemical deposition,accelerate the deposition rate and enhance the adhesion of the coating.The effect of coarsening time on the adhesion of copper layer was investigated by contrasting adhesion between copper layer and ceramic substrate before printing seed layer.In the optimized preparation conditions,the copper electrode is bright and the copper particles are densely packed.In addition,the copper layer possesses the properties of high temperature resistance and excellent solderability.The adhesion of the copper layer on the ceramic substrate can reach 2.6 kg/cm2,the resistivity is as low as 3.6 ??·cm.The capacitance and capacity loss of copper electrode ceramic capacitors have reached the industrial application requirements.The preparation technology of base metal electrode for ceramic capacitor developed in this paper has the advantages of simple process,low cost and industrialized production,and the whole preparation process can obtain excellent base metal electrode without high temperature sintering.This can provides a practical technical reference for the ceramic capacitor electrodes replacing noble metal with base metal.