The Processing Research Of Using Silver/conductive Ceramics Composite Inter-electrode Paste To Make Multi-layer Apparatus

With the development of Surface Mounting Technology (SMT) and the miniaturization, lightweight and performance-enhancing of electronic equipments, the multilayer chip components have been the mainstream products of the society. When manufacturing, the multilayer inter-electrode occupy higher and higher proportion in total cost for multilayer chip components because the multilayer technology has greatly increased the areas of inter-electrode. Moreover, the exiting inter-electrode paste is mainly made from precious metal materials, such as Pd, Ag, Bd-Ag, Pt, which lead to high production cost. Based on this background, this dissertation focuses on the research of inter-electrode paste that is suitable for production as well as low in price. Since the conductive ceramics have low resistance, high melting point, stable character and similar thermal expansion coefficient with ceramic medium, silver/conductive ceramics composite electrode paste, which would meet the production requirement and replace the silver paste, has been successfully made by doping the conductive ceramic powers into the traditional silver paste.Our team has studied the microstructure of silver/conductive ceramics composite electrode. In this dissertation, main research has been made on the thermal property of silver/conductive ceramics composite inter-electrode paste and develops a pilot experiment in which, the silver/conductive ceramics composite electrode paste can be used for production.The SEM and XRD analysis of the silver/conductive ceramics composite electrode shows that the same as silver paste electrode, silver/conductive ceramics composite electrode also has shining, smooth and compact sintered surface, without splits. And there is not any change in structure of conductive ceramics and silver during sintering. In addition, silver/conductive ceramics composite electrode forms net-channel structure. The conductivity of composite electrode has little change when the content of conductive ceramics is smaller than 12%.This kind of conductive ceramics has little effect on resistivity of composite electrode when the content of conductive ceramics is smaller than 15%. With the same content of conductive ceramics, the smaller the conductive ceramics grains are, the lower the resistivity of composite electrode is. Sintering temperature has little effect on room temperature resistivity of composite electrode.In this dissertation, we mainly research the thermal property of silver/conductive ceramics composite electrode paste.Firstly, we have done the differential thermal analysis experiment on the silver/conductive ceramics composite electrode paste, the industrial used silver pulp and the industrial used NiCuZn ferrites powder.The results of the experiment show that both the series of LaNiO₃ and LaFe_0.25Ni₍0.75_O3 conductive ceramics composite electrode paste have the similar heating curves and the weightloss temperature ranges are basicaly all from 80℃to 300℃Although the weight losses are different, they are kept in allowable scope.Beyond the scope,there is no obvious weight loss. The DTA curves also have no obvious miscellaneous peaks, which implies that it is a heat absorption. The weight losses of the silver/conductive ceramics composite electrode paste ,the industrial used silver pulp and the industrial used NiCuZn ferrites powder can match in weightlessness sector and weightlessness.So the silver/conductive ceramics composite electrode paste and the industrial used NiCuZn ferrites powder can achieve the thermal response match.Then we have done the shrinkage experiment both on the silver/conductive ceramics composite electrode paste and the industrial used NiCuZn ferrites powder. The experimental analysis reveals that the shrinkage sector and shrinking percentage are almost consistent in theory.We draw the conclusion that they are basically match at shrinkage.Theoretically, silver paste can be replaced by silver/conductivity ceramics composite inter-electronic paste in aspects of conductivity and thermal performance. Therefore, we develop the pilot experiment in which, the silver/conductive ceramics composite electrode paste can be used for production. In this technological design, the inter-electronic paste can be divided into two types, the coil electrode paste and the point electrode paste and thus would be of great benefit to saving paste and mass production.