US Patent 9368460 Fan-out interconnect structure and method for forming same

A method embodiment includes forming a sacrificial film layer over a top surface of a die, the die having a contact pad at the top surface. The die is attached to a carrier, and a molding compound is formed over the die and the sacrificial film layer. The molding compound extends along sidewalls of the die. The sacrificial film layer is exposed. The contact pad is exposed by removing at least a portion of the sacrificial film layer. A first polymer layer is formed over the die, and a redistribution layer (RDL) is formed over the die and electrically connects to the contact pad.