Carrier Device With Ridge-Shaped Contacts For Thermal Stress

The patent replaces expensive ceramic substrates (aluminum nitride) with a more economical alternative structure consisting of a metal core printed circuit board with a specific layer construction. This substitution uses readily available, cost-effective materials while maintaining the necessary thermal and mechanical properties through clever structural design rather than relying on expensive bulk ceramic materials.

The patent employs a composite structure comprising multiple layers with different functions: a metal core layer for thermal management, dielectric layers for electrical insulation, and copper traces for electrical connection. This composite approach allows each layer to be optimized independently for its specific function, achieving overall system performance comparable to expensive monolithic ceramic substrates but at much lower cost.

The patent introduces a flexible organic solderable substrate layer that acts as a compliant interface between the rigid metal core and the semiconductor chip. This thin film structure provides the necessary mechanical flexibility and ductility to prevent panel fracture while maintaining effective thermal pathways through the metal core, thus resolving the contradiction between thermal performance and mechanical brittleness.

The patent changes the material parameters of the substrate system by using a metal core with high thermal conductivity combined with a flexible organic substrate, rather than relying on the inherent brittleness of ceramic materials. This parameter change in material selection and structural configuration maintains thermal dissipation effectiveness while dramatically improving mechanical ductility and resistance to panel fracture.

The patent introduces a dielectric layer with intermediate thermal and mechanical properties between the high-CTE metal core and the low-CTE semiconductor chip. This intermediary layer acts as a stress buffer that accommodates the CTE mismatch, preventing excessive mechanical stress and deformation while allowing the use of cost-effective metal core substrates instead of expensive CTE-matched ceramic materials.

The patent modifies the thermal-mechanical parameters of the overall substrate system by carefully selecting and combining materials with complementary properties. The metal core provides high thermal conductivity and low cost, while the dielectric and organic substrate layers provide CTE buffering and mechanical compliance, achieving an optimal balance between cost, thermal performance, and stress management that neither material could achieve alone.