Heat protection coatings for high temperature electronics

Highly-integrated electronic devices and printed circuit boards need to be protected against overheating. In this disquisition a concept is introduced to improve the thermal management of coated assemblies by means of functional additives based on earlier works [4]. It has already been proven that paraffin wax, zeolite molecular sieve and silica gel have the potential as thermal energy storage systems due to phase transition effects and sorption [1], [5], [6]. Here the cooling effects of these materials were analyzed by using a heating element (constantan on ceramic substrate) and chip resistors with different package sizes (2512, 1206, 0805, 0603). The covering of these testing elements with the investigated additives lead to a significant delayed heating and therewith to a short-period heat protection at pulse load condition. Nevertheless a re-cooling of the system could regenerate the cooling effects of the additives for multiple utilization; paraffin wax due to refreezing and zeolite/silica gel due to rehydration. The Application for coating technology indicates a significant improvement of thermal properties.