Mechanical property and reliability of anisotropic conductive adhesive in surface mount applications

Anisotropic conductive adhesive (ACA) offers a promising solution for fine-pitch interconnections, which is low cost, low temperature and environmentally clean. Good mechanical property and high reliability are both required for ACAs to be an alternative of solders. In this study, three types of ACAs and one lead-free solder were selected to investigate their mechanical properties and reliabilities. Shear strength test was conducted to study the mechanical property of the samples. Reflow test was performed to examine if the ACA could be compatible with SMT process, and the shock resistance was studied by the drop test. In addition, the temperature cycling test (−40 °C to 125 °C) and the 85 °C /85% RH thermal humidity storage test were conducted to study the reliability.