Semiconductor Package and Method of Forming Same

In an embodiment, a method includes attaching a first package component to a first carrier, the first package component comprising: an aluminum pad disposed adjacent to a substrate; a sacrificial pad disposed adjacent to the substrate, the sacrificial pad comprising a major surface opposite the substrate, a protrusion of the sacrificial pad extending from the major surface; and a dielectric bond layer disposed around the aluminum pad and the sacrificial pad; attaching a second carrier to the first package component and the first carrier, the first package component being interposed between the first carrier and the second carrier; removing the first carrier; planarizing the dielectric bond layer to comprise a top surface being coplanar with the protrusion; and etching a portion of the protrusion.