Copper interposer for reducing warping of integrated circuit packages and method of making IC packages

摘要

A stacked die integrated circuit assembly comprising: 1) a substrate; 2) a first integrated circuit die mounted on the substrate; 3) a copper interposer mounted on the first integrated circuit die; and 4) a second integrated circuit die mounted on the copper interposer. The copper interposer significantly reduces the warping of the stacked die IC assembly caused by the warping of the substrate due to thermal changes in the substrate. The copper interposer has a significantly higher coefficient of thermal expansion than a conventional silicon (Si) interposer. The higher CTE enables the copper interposer to counteract the substrate warping.