Thermal and Stress Analysis of 3D-ICs with Celsius Thermal Solver

As electronics get smaller and faster, the environment for thermal issues is becoming more and more challenging. These problems are widespread and can appear in the chip, the board, the package, and the entire system.

3D-ICs integrate many dies (Figure 1, left) that are densely packed, which leads to heat generation resulting in a rise in temperature that causes performance issues. Consequently, it is important to accurately place the temperature sensor in the hot spot to quickly capture and mitigate the temperature rise. In packages and PCBs (Figure 1, center), the thermal challenges are due to the Joule heating impact, the infrared (IR) drop, and performance.

In 3D-ICs, these issues are exacerbated because of the multiple dies. There is non-homogenous power distribution inside the chiplet stacks, and greater thermal resistance due to the insulating dielectrics. Additionally, new stress is emerging due to 3D-IC stacking, bounding, and soldering, TSV drilling and filling, wafer and die thinning, and more.

Several years ago, Cadence introduced the Celsius Thermal Solver to address these thermal heating challenges in chips, packages, and systems. The Celsius Thermal Solver is the industry’s first complete electrothermal co-simulation solution for the full hierarchy of electronic systems from ICs to physical enclosures. The tool offers end-to-end capabilities for in-design through to signoff (Figure 2).

The advantages the Celsius Thermal Solver provides include integration with other Cadence design tools, accuracy with both finite element analysis (FEA) and computational fluid dynamics (CFD), high performance through distributed computing that significantly shortens simulation time, and expanded capacity to import detailed package and PCB models (Figure 3).

To understand in detail the cross-fabric thermal and stress challenges introduced by 3D-ICs and how the Cadence® Celsius Thermal Solver helps designers analyze the impact and develop strategies to mitigate this impact read here