The application of flip chip bonding technology using anisotropic conductive film to the mobile communications terminals

Abstract

In the field of mobile communications systems, the terminals have been downsized and given higher functions very rapidly. High-density surface mount technology is therefore required. For this reason, flip chip bonding (FCB) technology, which is the ultimate high-density surface mount technology at present, has been developed in Toshiba's Hino Works. This technology has been developed by using gold ball bumps and anisotropic conductive film (ACF). Bondability and reliability after FCB and after reflow soldering had already been confirmed for experimental materials. As the next items in the development, bondability and reliability after reflow soldering as well as after FCB were confirmed on the products. Also, the bonding process for the products was established. Moreover, mass production technology using the FCB method has been developed with fully automatic bonding machines and applied to the LCD module for a pager, which is one of the mobile communications terminals.