| abstract |
A substrate and a method of making a substrate having a functionally gradient coefficient of thermal expansion are described herein. A system having a silicon die, an organic package substrate, and a substrate having a functionally gradient coefficient of thermal expansion, connecting the silicon die and the organic substrate is also described. The coefficient of thermal expansion at the upper surface of the substrate matches the coefficient of thermal expansion of the die, the coefficient of thermal expansion at the lower surface of the substrate matches the coefficient of thermal expansion of the package substrate, and the substrate has one or more coefficients of thermal expansion between the coefficients of thermal expansion of the upper and lower surfaces. |