Calibrated fast thermal calculation and experimental characterization of advanced BEOL stacks

Abstract

In this work, we present a fast evaluation methodology to aid the thermal-aware BEOL design with a quick estimation of out-of-plane layer equivalent thermal properties based on design rules for dimensions and densities. The method is calibrated with a detailed FE thermal simulation and is applicable to realistic back-end-of-line (BEOL) connectivity. With this method, a breakdown analysis is performed on an advanced 3 nm 14-layer BEOL stack. Thermal contributions of individual layers and impacts of dielectric and metallization choices are benchmarked. Furthermore, a dedicated multi-layer BEOL test vehicle is designed in a 28nm foundry CMOS technology. The out-of-plane thermal coupling is experimentally characterized, and consistent measurement and modeling results are obtained.