Structural Analysis of Anisotropic Conductive Film for Liquid Crystal Displays and Semiconductor Packaging Applications

Anisotropic conductive film (ACF) has gained widespread attention and application in the field of electronic materials as the most reliable narrow-pitch electrode vertical interconnect material. In this study, we systematically investigate the influence of different ACF structural designs on electrode bonding effects during the preparation of ACF and bonding process for fine-pitch electrodes. As results, compared to traditional single layer ACF with uniformly distributed conductive particles, double layer ACF with selectively distributed conductive particles on one side has significant advantages in terms of particle consumption, electrode short-circuit probability, and capture rate. On the one hand, ACF with a double-layer structure can avoid excessive aggregation of conductive particles between electrodes caused by resin flow during bonding process, thus preventing short circuits. On the other hand, ACF with a double-layer structure can achieve the same bonding electrical connection effect as single-layer ACF with a particle density of 10,000 pcs/mm² when the conductive particle density is only 4,000 pcs/mm². Compared to the particle capture rate of 9.5% for single-layer ACF, the particle capture rate of double-layer ACF can reach 25.3%, demonstrating higher utilization efficiency of conductive particles.