Signal and power integrity analysis of a 256-GB/s double-sided IC package with a memory controller and 3D stacked DRAM

Abstract

This paper presents signal and power integrity analysis of a double-sided flip-chip package. A memory controller is attached on one side of the organic substrate, and 3D-stacked, disaggregated memory chips, integrated with through silicon vias (TSVs), are connected on the opposite side. The signaling path of this 3D memory system consists of a short channel consisting of wafer-level redistribution layer (RDL) traces and small TSV vias. The signal integrity is not a source of concern for this extremely short channel; power integrity, however, poses significant challenges and consequently can limit the achievable data rate of this system. The double-sided flip-chip packaging p resents unique challenges in the design of l o w-impedance the power delivery network (PDN) and circuit design with low-sensitivity to power supply noises. All physical layers are code sign to optimize the integrated 3D package within electrical and manufacturing constraints in conjunction with robust circuit design that meets the power constraint. The detailed signal integrity analysis is presented to design robust link with low-swing signals and power integrity analysis to optimize the PDN designs to meet the PDN impedance targets.