An accurate electromagnetic modeling of the die-to-die interconnect link for gigabit systems applications

The cost-effective design of gigabit per second signaling (Gb/s) for the interconnect systems requires optimizing components with accurate full channel simulations. The gigabit system performance is often defined in the time-domain (TD), but the modeling and characterization for the interconnect structures are done in the frequency-domain (FD). Due to non-linear behavior of the devices, the relation between FD and TD performances is not intuitively obvious, and therefore it is necessary to perform accurate analysis in both domains. To achieve an accurate modeling of the complex packaging structure often used a full-wave modeling tool that analyzes the propagation of electromagnetic waves through a three-dimensional model. In addition to the needs of characterization of the extended packaging boundaries, the accurate modeling utilizes a frequency-dependant material characterization. This paper describes the electromagnetic modeling methods, such as use of the frequency-dependent material properties, the method of discontinuity segmentation, and the validation technique. The vector network analyzer (VNA) where used for validation and choosing the best modeling method. Using measured and modeled data, we provide simulation in the time and the frequency domain, with comparison results. Good correlation between the modeling and measurement is reported in this paper.