Full-Wave Electromagnetic Simulation Approach for Integrated 3D-IC Design

This paper utilizes FEM (Finite Element Method) based full-wave 3D electromagnetic simulation tool by Ansys HFSS (High-Frequency Structure Simulator) to solve complex 3D-IC systems. Fusion of powerful advanced meshing and solving technologies referred to as “Mesh Fusion”, is employed to handle different scales of geometries or regions ranging from nanometers to centimeters. Each region including Package, Interposer, logic die (CPU, Central Processing Unit), and eight stacked HBM dies are meshed parallelly and independently by optimum mesh algorithms. Fully coupled fields are generated across different regions. CPU Die and HBM's are connected through a silicon interposer placed on a Ball-Grid Array package and are communicating at a Nyquist data rate of 5.8 Gbps. Signal integrity parameters such as return loss, insertion loss, near and far end crosstalk parameters, and eye diagram opening are observed for high-speed data, strobe lines between the CPU die and HBM. The significance of performing integrated 3D-IC simulation in comparison to isolated standalone interposers on these parameters is also investigated. In addition, electric field coupling among different regions is studied in detail.