Development of accelerated aging test for ESD/EMI protective materials and electrical discontinuity at seams and interconnections

摘要

Many studies of new protective ESD/EMI materials, such as antistats, and conductive members of a seam or interconnection, such as make up corrodible seams and interconnections, should be regarded as incomplete. Little or no attention has been paid to changes in essential material properties exposed to various environments because the test takes too much time. A procedure for development of accelerated tests is described. There are a number of variables that can be used to reduce the time usually required for accelerated aging tests. These variables include but not limited to: temperature, percent relative humidity, mechanical and electrical properties. Examples from the literature are cited to show how temperature can be used to develop acceleration factors to reduce the time for aging in outgassing and resistivity aging. Corrosion reactions can degrade the ESD/EMI protected product by promoting electromagnetic emissions and also producing electrical discontinuity at seams(EDS) and interconnections (EDI). These EDS can result in secondary ESD events. EDI's can result in malfunctioning of circuits. Under these conditions temperature can be used to produce large acceleration factors thus reducing the time to simulate the lifetime aging process of the electronic product.