Nanofiber ACFs (anisotropic conductive films) for ultra-fine pitch interconnection

Abstract

The demands of smart devices such as smart phones or tablet PCs has risen dramatically over the last decades. Also the display technology has been continuously evolved into higher resolution technology such as ultra high definition (UHD) resulting in more I/O pins required. Therefore, ultra fine pitch packaging and interconnection technology has become very important in assembly processes. In electronic packaging industry, anisotropic conductive films (ACFs), well known adhesive interconnecting materials, consist of thermosetting resin and conductive particles in a film format, have been widely used. However, as the pitch has been narrowed, interconnection problems such as short circuit issue and high contact resistance issues have been raised with conventional ACFs bonding. As a result, a novel concept of ACFs called nanofiber ACFs was introduced before to solve these problems by our research group. Combining nanofiber and ACFs technology can provide a promising solution for fine pitch interconnection. Nanofiber can suppress the free movement of conductive particles of ACFs to prevent electrical interconnection problems such as short or high contact resistance.