New power delivery network(PDN) approach for extremely large FC-BGA with organic substrate based on over 1mm-thick core

In this paper, the authors propose two solutions for thick embedding capacitor that can be embedded in extremely large Flip Chip Ball Grid Array (FC-BGA) Package (PKG) using a Thick Core Substrate (TCS) with thickness of more than 1 mm.Firstly, the authors propose an embedded Capacitor Module (eCM) solution. In this solution, it is possible to package multiple capacitors into single capacitor module. To do that, mount multiple Multi-Layer Ceramic Capacitor (MLCC) on a substrate with external electrodes made of copper (Cu) and then perform molding. This solution is suitable for embedding capacitors into TCS because it allows control of thickness while packaging multiple capacitors. It also enables implementation of larger capacitance, and customization of size and capacitance according to System on Chip (SoC) requirements through the combinations of internal capacitors. Furthermore, it is effective for improving Power Delivery Network (PDN) performance as it allows to directly connect capacitance to the desired IP blocks according to SoC package design.Secondly, the authors propose Through Silicon Via (TSV)-based Stacked Silicon Capacitor (SSC). As presented by authors’ another paper [1], TSV-based SSC can be used for embedded Capacitor (eCAP) with TCS. A SSC is created by producing silicon capacitor wafers with applied TSV and stacking two identical wafers through wafer-to-wafer bonding. Repeat this process N times to fabricate SSC that consists of N silicon capacitors. SSC provides lower Equivalent Series Inductance (ESL) characteristics and N times higher capacitance compared to conventional silicon capacitors. SSC can be manufactured with the same thickness as that of the core layer of TCS. Additionally, SSC makes shortcut PDN design between die bumps and PKG balls through TSV, which further enhances PDN performance.This paper provides a comparative study on PDNs that are designed using Die Side Capacitor (DSC) versus PDNs that are designed using eCM and TSV-based SSCs in extremely large PKG. The simulation results related to impedance characteristics and voltage drop are presented based on Power Intergrity (PI) simulation experiments. In these experiments, an actual automotive SoC product that utilizes TCS PKG platform is evaluated.