Interposer structure for semiconductor package including peripheral metal pad around alignment mark and methods of fabricating same

Abstract

An interposer for a semiconductor package and a method of fabricating an interposer including a peripheral metal pad surrounding an alignment mark. The alignment mark and the surrounding peripheral metal pad are formed on a first dielectric material layer of the interposer. A second dielectric material layer is located over the first dielectric material layer and at least partially over the peripheral metal pad structure and includes an recess extending around a periphery of the alignment mark. A third dielectric material layer is located over the second dielectric material layer and extends into the recess and contacts the alignment mark, the first dielectric material layer, and optionally a portion of the peripheral metal pad. The peripheral metal pad may enhance the adhesion between the first, second and third dielectric material layers near the alignment mark structure and thereby reduce the likelihood of crack formation.