Broadband time-domain characterization of multiple flip-chip interconnects

This paper presents a comprehensive approach for the characterization of multiple flip-chip interconnects by three-dimensional finite-difference time-domain (FDTD) method. The behaviors of transition discontinuities in three coplanar waveguide (CPW) layers and four flip-chip bump interconnects are investigated for optimal packaging performance. The relationship between the reflection loss and the cross-section of bumps is discussed in detail. Results in this paper shows that FDTD is a reliable method to simulate and aid design of complicated package structures.