| Silver paste and other precious metal paste are widely used in the electronics industry because they have high conductivity and well application performance. But their developments are restricted as their high price. So more and more researchers are studing the base metal pastes.We use the silver-coated copper powder and the silver-coated glass bead , which were produced by Kunming HengDa scientific & technical corporation as conductive fillers, was fixed with resin to made conductive paste. Then the specification of those two new kinds of hypothermia polymer conductive paste were studied. Such as conducting and printing .Then A and F were chosen from six kinds of resins according to experiments. The best composition of the conductive paste were: silver-coated glass bead 60%～65%fixed with35%～40%A resin, 65%～70% fixed with 30%～35%F resin, silver-coated copper powder 70% fixed with 30%A or F resin. And the best operation conditions that fixed from the orthogonal experimentation were:Ag-glass besd paste with A resin was cured at 120℃ for about 40 min, Ag-glass besd paste with F resin was cured at 140℃ for about 30 min, Ag-Cu paste with A resin was cured at 140℃ for about 50 min, Ag-Cu paste with F resin was cured at 120℃ for about 40 min. Because the nano metal powder will be oxidatived at air,so the pastes that we made were put in the air for a period of time. Ag-glass bead paste that contain 20% and 40% silver were not oxidatived serious 72 days later. And the resistance changed less than 10%.But Ag-glass bead paste that contain 15% silver was not well as them,and the resistance changed more than 20%. Ag-Cu paste was oxidatived seriously,the resistance changed over 30%.In short,according to lots of experiments,the best paste was containing 30%～35%F resin and 65%～70% silver-coated glass bead ,then the paste was cured at 140℃ for about 30 min.The resistance was just 11.858 mΩ/□,and the resistance changed about less than 10% 72 days later. The conduction and oxidation resistance of this paste are well enough to replace of silver paste. |
