Recently, conductive adhesives have been considered as alternatives for replacing conventional solders in the mount technology of the electronic components on print circuit board (PCI), due to necessity to look for environment - friendly materials and fine pitch components. However, there is a little information about the behavior and properties of the isotropic conductive adhesives (as paste) for using in the mounting of the electronic components. The objective of this work was to study the physical and chemical properties, as well as the behavior of isotropic conductive adhesives aiming their use in the "soldering" of electronic components. Three different commercial isotropic conductive adhesives were utilized in this study. Firstly, thick films were prepared on glass substrate aiming to analyze the behavior of resistivity as a function of the time and temperature of cure. Secondly, the adhesives were utilized for fixing different kinds of electronic components on PCI. Then, the samples were characterized by optical and scanning electronic microscopy with the purpose of verifing the component/adhesive/PCI interface. Electric tests were realized to verify the viability of the use of these adhesives and the results are compared with the conventional solders. It was observed that the isotropic conductive adhesives showed properties compatible to conventional paste solders.
isotropic conductive adhesives; lead free solders; surface mount technology
