Wafer level packaging having bump-on-polymer structure

摘要

Kulicke & Soffa's Flip Chip Division (formerly Flip Chip Technologies), the market leader of wafer level packaging (WLP) technology, has developed a new WLP technology-the Spheron WLP~(TM). Spheron WLP~(TM) was developed with bump-on-polymer structure to decrease the input capacitance for high-speed applications. During development of the Spheron WLP~(TM) technology, a new polymer dielectric material was carefully selected from seven (7) materials that were tested in terms of reliability and manufacturability. The polymer selected demonstrated not only the best reliability but also provided exceptional manufacturability. The favorable mechanical toughness, high elongation, and excellent adhesion to organic and inorganic materials provided excellent performance in reliability tests.