US Patent 10573573 Package and package-on-package structure having elliptical conductive columns

A package includes a die, a plurality of first conductive structures, a plurality of second conductive structures, an encapsulant, and a redistribution structure. The die has an active surface and a rear surface opposite to the active surface. The first conductive structures and the second conductive structures surround the die. The first conductive structures include cylindrical columns and the second conductive structures include elliptical columns or conical frustums. The encapsulant encapsulates the die, the first conductive structures, and the second conductive structures. The redistribution structure is over the active surface of the die and the encapsulant. The redistribution structure is electrically connected to the die, the first conductive structures, and the second conductive structures.