Electric field effects on short-circuiting between adjacent joints in fine pitch anisotropically conductive adhesive interconnections

Anisotropic conductive adhesive films (ACFs) have been extensively used for Chip-On-Glass (COG) applications in the Liquid Crystal Display (LCD) industry. One of the very important performance requirements of using ACFs is not to create electric current leakage between adjacent joints as it may lead to abnormal display segment of the LCD. As this is one of the major concerns to the manufacturers, understanding of the failure mechanism can improve in the product reliability and reduce any economic or resources losses. In this work, the possibility of short-circuiting between adjacent joints in fine pitch ACF interconnections under the effects of electric field was investigated. Insulation resistance measurements of the selected adhesive joints against electric field strength 1V/μm for a 24 hrs test duration were discussed and analyzed. The results showed a strong dependence of curing degree of the ACFs on the chance of short-circuiting between adjacent joints under field effects.