ELECTRICAL PROPERTIES OF ADHESIVE JOINTS

摘要

Isotropic electrically conductive adhesives are usually manufactured with filler concentration sufficiently greater than percolation threshold to guarantee low resistance with allowance for manufacturing tolerances. But joint resistance and other electrical properties of adhesive joints depend on filler particle shapes and dimensions. The silver flakes, "heavy" silver and nano-silver powder as well as specially prepared highly porous very light silver particles were used as fillers. Adhesives were formulated on the base of two kinds of resin with two levels of the volume content of filler in adhesive. It was stated that the silver flakes with the particle size distribution ranges from 1 to 20μm with the maximum of 2 - 4μm, generally, is the best filler material. However, the adhesive with "heavy" silver manufactured on the base selected resin has lower joint resistance and the adhesive with porous silver are characterized by lower value of temperature coefficient of resistance. When volume content of filler in adhesive is greater than percolation threshold, the influence of the volume content on electrical properties of adhesive joints is statistically not important.