As Photonic Integrated Circuits (PICs) transition from 2D to 3D architectures, they offer substantial benefits in terms of integration density, allowing for more components to be packed into a smaller footprint. This leads to enhanced performance and functionality in a variety of applications, such as high-speed data transmission, advanced sensing, and quantum computing. However, the shift to 3D PICs also introduces significant thermal management challenges. As the packing density of active components increases, so does the potential for the formation of hotspots where heat accumulates, resulting in localized overheating. These thermal issues can degrade the performance of components, cause signal instability, and even lead to device failure if not effectively addressed.