Copper Conductor Paste And Its Properties

With price of precious metals rising in recent years and the pitfalls of precious metal pastes,the research and development on base metal paste has become a new hot spot.Copper paste which is used as a base metal paste has aroused people's wide attention and research.In this paper,the thick film metallization pastes have been mainly studied.And the aim is to improve the adhesion,solderability and reduce the sheet resistance.With the analyze of XRD,DTA,SEM et al,The preparation of the glass powder and copper paste on the properties of paste have been discussed.Through the melt-water quench,three different glass powder systems were prepared,and we also changed the glass powder content in the copper paste.At last,impacts of the glass phase on copper conductive film layer were discussed.Experiments show that:when we used SiO₂-B₂O₃-CaO glass system and the content of glass powder was 6%,the copper paste had good performance.XRD analysis showed that the glass crystallization will produce bad influence on the performance of the copper paste,and if the glass transition temperature is too high or too low,it would adverse impacted on the performance of the copper paste.When glass powder content is too low,it will not only affect the film adhesion,as there is no glass phase during sintering to improve the network structure,it will also seriously affect the conductivity of the membrane layer.When the glass powder content is large,glass particles float on the surface layer after sintering,it will not only reduces the adhesion and also influence the weldability of membrane layer.The smaller the particle size of glass is,the better glass wetting is.And the performance of copper paste is better.This paper discussed the preparation process of copper paste from the viscosity of paste,film thickness,flow time,sintering temperature,holding time and so on.we found that,The viscosity of the copper paste was 100-250Pa·s,leveling time was 15min,the thickness of the film was 12?m,the sintering temperature was 850 ?,holding time was 10min,the copper paste would had best performance.The film have good weldability,square resistance is 2.8 m ?/?,adhesive force is 22 N/cm2.The best formula of copper paste for copper powder:77%,glass powder 6%,organic carrier 17%.