3D-convolution based fast transient thermal model for 3D integrated circuits: methodology and applications

A thorough thermal analysis of integrated circuits (ICs) is essential to prevent temperature driven reliability issues, which might cause the failure of microelectronic devices. The classical analysis approach is based on finite element methods (FEM). However, in the last decades, other computational methodologies have been developed with the aim to obtain results more quickly and at a reasonable accuracy. In this paper, a transient fast thermal model (TFTM) methodology for 3DICs based on 3D-convolution and fast Fourier transform is presented. This methodology allows to quickly and accurately predict the temporal evolution of the chip temperature distribution, due to power dissipation that can be non-uniform both in time and space, in all tiers of the 3D package. In the first part of the paper the computational methodology is derived and described. Next, results are presented and validated with respect to conventional FEM simulations, showing good accuracy and computational time reduction. A realistic case, wherein different load switching scenarios are compared for a commercial floor-plan, is analyzed as an example of the applicability of the presented methodology. The speed of this algorithm, based on 3D-convolution, is compared with the one of previous work based on 2D-convolution and subseq uent time superposition.