  Environmental sustainability is crucial for Integrated Circuits (ICs) across
their lifecycle, particularly in manufacturing and use. Meanwhile, ICs using
3D/2.5D integration technologies have emerged as promising solutions to meet
the growing demands for computational power. However, there is a distinct lack
of carbon modeling tools for 3D/2.5D ICs. Addressing this, we propose
3D-Carbon, an analytical carbon modeling tool designed to quantify the carbon
emissions of 3D/2.5D ICs throughout their life cycle. 3D-Carbon factors in both
potential savings and overheads from advanced integration technologies,
considering practical deployment constraints like bandwidth. We validate
3D-Carbon's accuracy against established baselines and illustrate its utility
through case studies in autonomous vehicles. We believe that 3D-Carbon lays the
initial foundation for future innovations in developing environmentally
sustainable 3D/2.5D ICs. Our open-source code is available at
https://github.com/UMN-ZhaoLab/3D-Carbon.
