Advanced heterogeneous integration through 3D technology has become a critical enabler for modern integrated circuits (ICs), addressing many of the inherent limitations of traditional 2D architectures. However, this progress introduces significant thermal management challenges due to increased power consumption, making accurate thermal estimation essential. The use of fast and accurate thermal models is therefore crucial for thermal-aware design from the early stages of IC development. Traditional methods such as finite element methods (FEM) offer high accuracy but face challenges in system-level analysis due to computational inefficiency. To overcome this, compact thermal models (CTMs) have been introduced, significantly improving simulation time with minimal loss of accuracy.