A 3D IC package includes a bottom die having a back interconnect side opposing a front device side, the back interconnect side having a plurality of bottom die interconnects extending thereto. A top die has a front device side opposing a back side, the front device side having a plurality of top die interconnects. An interposer includes a redistribution layer (RDL) between the bottom die and the top die, the RDL including a plurality of wiring layers extending from back side RDL interconnects thereof to front side RDL interconnects thereof. An under bump metallization (UBM) couples the back side RDL interconnects to the plurality of top die interconnects at a first location, and the front side RDL interconnects are coupled to the plurality of bottom die interconnects at a second location. The first location and second location may not overlap.

A Cu.sub.3Sn electrical interconnect and method of making same in an electrical device, such as for hybrid bond 3D-integration of the electrical device with one or more other electrical devices. The method of forming the Cu.sub.3Sn electrical interconnect includes: depositing a Sn layer in the via hole; depositing a Cu layer atop and in contact with the Sn layer; and heating the Sn layer and the Cu layer such that the Sn and Cu layers diffuse together to form a Cu.sub.3Sn interconnect in the via hole. During the heating, a diffusion front between the Sn and Cu layers moves in a direction toward the Cu layer as initially deposited, such that any remaining Cu layer or any voids formed during the diffusion are at an upper region of the formed Cu.sub.3Sn interconnect in the via hole, thereby allowing such voids or remaining material to be easily removed.

A Cu.sub.3Sn electrical interconnect and method of making same in an electrical device, such as for hybrid bond 3D-integration of the electrical device with one or more other electrical devices. The method of forming the Cu.sub.3Sn electrical interconnect includes: depositing a Sn layer in the via hole; depositing a Cu layer atop and in contact with the Sn layer; and heating the Sn layer and the Cu layer such that the Sn and Cu layers diffuse together to form a Cu.sub.3Sn interconnect in the via hole. During the heating, a diffusion front between the Sn and Cu layers moves in a direction toward the Cu layer as initially deposited, such that any remaining Cu layer or any voids formed during the diffusion are at an upper region of the formed Cu.sub.3Sn interconnect in the via hole, thereby allowing such voids or remaining material to be easily removed.

In some embodiments, the present disclosure relates to a method including forming an interconnect structure over a substrate. A bond pad may be coupled to the interconnect structure, and a polymeric material may be deposited over the bond pad. In some embodiments, the method further includes performing a patterning process to remove a portion of the polymeric material to form an opening in the polymeric material. The opening directly overlies and exposes the bond pad. Further, the method includes a first cleaning process. The polymeric material is cured to form a polymeric protection layer, and a second cleaning process is performed.

A semiconductor device includes a conductive component on a substrate, a passivation layer on the substrate and including an opening that exposes at least a portion of the conductive component, and a pad structure in the opening and located on the passivation layer, the pad structure being electrically connected to the conductive component. The pad structure includes a lower conductive layer conformally extending on an inner sidewall of the opening, the lower conductive layer including a conductive barrier layer, a first seed layer, an etch stop layer, and a second seed layer that are sequentially stacked, a first pad layer on the lower conductive layer and at least partially filling the opening, and a second pad layer on the first pad layer and being in contact with a peripheral portion of the lower conductive layer located on the top surface of the passivation layer.

A method for sawing a semiconductor wafer is provided. The method includes sawing a semiconductor wafer to form a first opening. In addition, the semiconductor wafer includes a dicing tape and a substrate attached to the dicing tape by a die attach film (DAF), and the first opening is formed in an upper portion of the substrate. The method further includes sawing through the substrate and the DAF of the semiconductor wafer from the first opening to form a middle opening under the first opening and a second opening under the middle opening, so that the semiconductor wafer is divided into two dies. In addition, a slope of a sidewall of the middle opening is different from slopes of sidewalls of the first opening and the second opening.

A method for sawing a semiconductor wafer is provided. The method includes sawing a semiconductor wafer to form a first opening. In addition, the semiconductor wafer includes a dicing tape and a substrate attached to the dicing tape by a die attach film (DAF), and the first opening is formed in an upper portion of the substrate. The method further includes sawing through the substrate and the DAF of the semiconductor wafer from the first opening to form a middle opening under the first opening and a second opening under the middle opening, so that the semiconductor wafer is divided into two dies. In addition, a slope of a sidewall of the middle opening is different from slopes of sidewalls of the first opening and the second opening.

A bonding pad structure and a method of manufacturing a bonding pad structure are provided. The bonding pad structure includes a carrier, a first conductive layer disposed over the carrier, a second conductive layer disposed on the first conductive layer and contacting the first conductive layer, and a third conductive layer disposed on the second conductive layer and contacting the second conductive layer. The bonding pad structure also includes a first passivation layer disposed on the first conductive layer and contacting at least one of the first conductive layer or the second conductive layer. An upper surface of the third conductive layer facing away from the carrier is exposed from the first passivation layer.

A bonding pad structure and a method of manufacturing a bonding pad structure are provided. The bonding pad structure includes a carrier, a first conductive layer disposed over the carrier, a second conductive layer disposed on the first conductive layer and contacting the first conductive layer, and a third conductive layer disposed on the second conductive layer and contacting the second conductive layer. The bonding pad structure also includes a first passivation layer disposed on the first conductive layer and contacting at least one of the first conductive layer or the second conductive layer. An upper surface of the third conductive layer facing away from the carrier is exposed from the first passivation layer.

A method for sawing a semiconductor wafer is provided. The method includes sawing a semiconductor wafer to form a first opening. In addition, the semiconductor wafer includes a dicing tape and a substrate attached to the dicing tape by a die attach film (DAF), and the first opening is formed in an upper portion of the substrate. The method further includes sawing through the substrate and the DAF of the semiconductor wafer from the first opening to form a middle opening under the first opening and a second opening under the middle opening, so that the semiconductor wafer is divided into two dies. In addition, a slope of a sidewall of the middle opening is different from slopes of sidewalls of the first opening and the second opening.