An integrated circuit (IC) package, comprising a die having a first set of interconnects of a first pitch, and an interposer comprising an organic substrate having a second set of interconnects of a second pitch. The interposer also includes an inorganic layer over the organic substrate. The inorganic layer comprises conductive traces electrically coupling the second set of interconnects with the first set of interconnects. The die is attached to the interposer by the first set of interconnects. In some embodiments, the interposer further comprises an embedded die. The IC package further comprises a package support having a third set of interconnects of a third pitch, and a second inorganic layer over a surface of the interposer opposite to the die. The second inorganic layer comprises conductive traces electrically coupling the third set of interconnects with the second set of interconnects.

A circuit board according to an embodiment includes a first insulating layer; a second insulating layer disposed on the first insulating layer; a third insulating layer disposed on the second insulating layer; a fourth insulating layer embedded in the third insulating layer; and a fifth insulating layer disposed on the third insulating layer, wherein the first insulating layer, the second insulating layer, the third insulating layer, and the fourth insulating layer are provided with different materials, wherein the second insulating layer and the fifth insulating layer are provided with a same material, and a thickness in a vertical direction between an upper surface of the fourth insulating layer and an upper surface of the third insulating layer is smaller than a thickness of the second insulating layer in the vertical direction.