A semiconductor substrate is provided with an annular cavity extending from a front side of the substrate to an opposite rear side. A metallization is applied in the annular cavity, thereby forming a through-substrate via and leaving an opening of the annular cavity at the front side. A solder ball is placed above the opening and a reflow of the solder ball is effected, thereby forming a void of the through-substrate via, the void being covered by the solder ball.

A semiconductor substrate is provided with a through-substrate via comprising a metallization and an opening. A solder ball is placed on the opening. A reflow of the solder ball is performed in such a way that the solder ball closes the through-substrate via and leaves a void in the through-substrate via.

The semiconductor device comprises a semiconductor substrate (10) with a metallization (111) having an upper terminal layer (22) located at a front side (20) of the substrate. The metallization forms a through-substrate via (23) from the upper terminal layer to a rear terminal layer (13) located opposite to the front side at a rear side (21) of the substrate. The through-substrate via comprises an annular cavity (18) and a void (101), which may be filled with air or another gas. A solder ball (100) closes the void without completely filling it. A variety of interconnections for three-dimensional integration is offered by this scheme.

The semiconductor device comprises a semiconductor substrate (10) with a metallization (111) having an upper terminal layer (22) located at a front side (20) of the substrate. The metallization forms a through-substrate via (23) from the upper terminal layer to a rear terminal layer (13) located opposite to the front side at a rear side (21) of the substrate. The through-substrate via comprises an annular cavity (18) and a void (101), which may be filled with air or another gas. A solder ball (100) closes the void without completely filling it. A variety of interconnections for three-dimensional integration is offered by this scheme.

The semiconductor device comprises a semiconductor substrate (10) with a metallization (111) having an upper terminal layer (22) located at a front side (20) of the substrate. The metallization forms a through-substrate via (23) from the upper terminal layer to a rear terminal layer (13) located opposite to the front side at a rear side (21) of the substrate. The through-substrate via comprises a void (101), which may be filled with air or another gas. A solder ball (100) closes the void without completely filling it. A variety of interconnections for three dimensional integration is offered by this scheme.

A semiconductor substrate is provided with a through-substrate via comprising a metallization and an opening. A solder ball is placed on the opening. A reflow of the solder ball is performed in such a way that the solder ball closes the through-substrate via and leaves a void in the through-substrate via.

A method of forming an integrated circuit package includes following operations. A padding layer is formed on a portion of a carrier. A first semiconductor die is placed on the padding layer and a second semiconductor die is placed on the carrier. The first semiconductor die and the second semiconductor die are encapsulated with a first encapsulation layer. A first redistribution layer structure is formed over the first semiconductor die, the second semiconductor die and the first encapsulation layer. A third semiconductor die is placed on the first redistribution layer structure. The third semiconductor die is encapsulated with a second encapsulation layer. A second redistribution layer structure is formed over the third semiconductor die and the second encapsulation layer. The carrier is debonded. The padding layer is removed, and therefore, a recess is formed in the first encapsulation layer.

A method of forming an integrated circuit package includes following operations. A padding layer is formed on a portion of a carrier. A first semiconductor die is placed on the padding layer and a second semiconductor die is placed on the carrier. The first semiconductor die and the second semiconductor die are encapsulated with a first encapsulation layer. A first redistribution layer structure is formed over the first semiconductor die, the second semiconductor die and the first encapsulation layer. A third semiconductor die is placed on the first redistribution layer structure. The third semiconductor die is encapsulated with a second encapsulation layer. A second redistribution layer structure is formed over the third semiconductor die and the second encapsulation layer. The carrier is debonded. The padding layer is removed, and therefore, a recess is formed in the first encapsulation layer.

According to one embodiment, a semiconductor device includes a first switch provided with a first electrode and a second electrode, a second switch provided with a third electrode and a fourth electrode, a first capacitor including a first wiring layer connected to the third electrode, a second wiring layer connected to the first electrode, and a first dielectric layer, a substrate, a third wiring layer connected to the first wiring layer and applied with a first voltage, a fourth wiring layer connected to the second wiring layer and applied with a second voltage, and a fifth wiring layer connected to the second and fourth electrodes, and applied with a third voltage. The first capacitor is arranged between the first and second switches. The third electrode faces the first electrode. The fourth electrode faces the second electrode and is connected to the second electrode in series.