A method includes forming a first through-via from a first conductive pad of a first device die, and forming a second through-via from a second conductive pad of a second device die. The first and second conductive pads are at top surfaces of the first and the second device dies, respectively. The first and the second conductive pads may be used as seed layers. The second device die is adhered to the top surface of the first device die. The method further includes encapsulating the first and the second device dies and the first and the second through-vias in an encapsulating material, with the first and the second device dies and the first and the second through-vias encapsulated in a same encapsulating process. The encapsulating material is planarized to reveal the first and the second through-vias. Redistribution lines are formed to electrically couple to the first and the second through-vias.

A package structure includes a semiconductor die, a first insulating encapsulant, a plurality of first conductive features, an interconnect structure and bump structures. The semiconductor die includes a plurality of conductive pillars made of a first material. The first insulating encapsulant is encapsulating the semiconductor die. The first conductive features are disposed on the semiconductor die and electrically connected to the conductive pillars. The first conductive features include at least a second material different from the first material. The interconnect structure is disposed on the first conductive features, wherein the interconnect structure includes a plurality of connection structures made of the second material. The bump structures are electrically connecting the first conductive features to the connection structures, wherein the bump structures include a third material different from the first material and the second material.

A method includes forming a first through-via from a first conductive pad of a first device die, and forming a second through-via from a second conductive pad of a second device die. The first and second conductive pads are at top surfaces of the first and the second device dies, respectively. The first and the second conductive pads may be used as seed layers. The second device die is adhered to the top surface of the first device die. The method further includes encapsulating the first and the second device dies and the first and the second through-vias in an encapsulating material, with the first and the second device dies and the first and the second through-vias encapsulated in a same encapsulating process. The encapsulating material is planarized to reveal the first and the second through-vias. Redistribution lines are formed to electrically couple to the first and the second through-vias.

A method includes forming a first through-via from a first conductive pad of a first device die, and forming a second through-via from a second conductive pad of a second device die. The first and second conductive pads are at top surfaces of the first and the second device dies, respectively. The first and the second conductive pads may be used as seed layers. The second device die is adhered to the top surface of the first device die. The method further includes encapsulating the first and the second device dies and the first and the second through-vias in an encapsulating material, with the first and the second device dies and the first and the second through-vias encapsulated in a same encapsulating process. The encapsulating material is planarized to reveal the first and the second through-vias. Redistribution lines are formed to electrically couple to the first and the second through-vias.

A method includes forming a first through-via from a first conductive pad of a first device die, and forming a second through-via from a second conductive pad of a second device die. The first and second conductive pads are at top surfaces of the first and the second device dies, respectively. The first and the second conductive pads may be used as seed layers. The second device die is adhered to the top surface of the first device die. The method further includes encapsulating the first and the second device dies and the first and the second through-vias in an encapsulating material, with the first and the second device dies and the first and the second through-vias encapsulated in a same encapsulating process. The encapsulating material is planarized to reveal the first and the second through-vias. Redistribution lines are formed to electrically couple to the first and the second through-vias.