The increasing level of integration and operating speed ofintegrated circuit chips is leading to larger chip sizes with higherpower dissipation. Electronic packages incorporating such devicesrequire low cost and highly efficient thermal management materials forreliable performance of the device. W/Cu and Mo/Cu materials are oftenused as heat sinks or substrates for direct bonding the Si devices.While W and Mo based materials possess the required thermal expansionand thermal conductivity for electronic packages, they are difficult tomachine and fabricate into intricate shapes. This report describes a newthermal management material, called CUVAR, which possesses low thermalexpansion and high thermal conductivity. CUVAR is an extruded compositeof copper and Invar powders, where Invar restrains thermal expansionwhile copper provides thermal conductivity. Most importantly, CUVAR iseasily machined, enabling high speed and efficient fabrication ofcomponents. It is readily plated with copper, nickel, silver or gold forjoining and finishing. CUVAR is an alternative to low thermal expansionmaterials such as Kovar and Alloy 42 with a much higher thermalconductivity. CUVAR can also be a replacement for the conventional W andMo based thermal management materials with the advantages of low costand excellent fabricability for high volume applications
展开▼
