CoolSem Technologies, a semiconductor thermal management company, has closed a pre-seed funding round led by High-Tech Gründerfonds (HTGF), with participation from KBC Focus Fund NV, the Brabant Development Agency (BOM), and TTT Green Tech B.V. (SHIFT Invest). Founded in 2025 and headquartered in Eindhoven, the Netherlands, CoolSem Technologies develops wafer-level thermal management solutions for advanced semiconductor and photonic devices. Its WaLTIS multilayer stack replaces conventional substrates with an engineered structure designed to improve heat dissipation, mechanical stability, and device reliability, enabling higher performance and longer device lifetimes. ## The thermal management challenge As chips become an increasingly critical resource, pressure on raw materials is rising, and heat management remains a persistent constraint on performance. CoolSem Technologies aims to address these challenges by improving energy efficiency, extending hardware lifetimes, and enabling the reuse of scarce materials, supporting a more sustainable and circular semiconductor industry. CoolSem Technologies’ CEO, André van Geelen, said that thermal constraints are increasingly limiting semiconductor performance, particularly in RF, photonics, and power applications, where traditional materials and packaging approaches are nearing their physical limits. ## Next Steps The company will use the funding to advance its WaLTIS technology from concept to engineering samples, with validation by leading customers in RF, power, and photonics, supporting qualification activities and real-world performance testing. Olaf Joeressen, Senior Investment Manager at HTGF, added that the technology has the potential to become a core component of future chip thermal design, as thermal management becomes ever more critical to semiconductor performance.