A method of forming semiconductor devices includes providing a wafer having a first side and second side, electrically conductive pads at the second side, and an electrically insulative layer at the second side with openings to the pads. The first side of the wafer is background to a desired thickness and an electrically conductive layer is deposited thereon. Nickel layers are simultaneously electrolessly deposited over the electrically conductive layer and over the pads, and diffusion barrier layers are then simultaneously deposited over the nickel layers. Another method of forming semiconductor devices includes depositing backmetal (BM) layers on the electrically conductive layer including a titanium layer, a nickel layer, and/or a silver layer. The BM layers are covered with a protective coating and a nickel layer is electrolessly deposited over the pads. A diffusion barrier layer is deposited over the nickel layer over the pads, and the protective coating is removed.

A method of forming semiconductor devices includes providing a wafer having a first side and second side, electrically conductive pads at the second side, and an electrically insulative layer at the second side with openings to the pads. The first side of the wafer is background to a desired thickness and an electrically conductive layer is deposited thereon. Nickel layers are simultaneously electrolessly deposited over the electrically conductive layer and over the pads, and diffusion barrier layers are then simultaneously deposited over the nickel layers. Another method of forming semiconductor devices includes depositing backmetal (BM) layers on the electrically conductive layer including a titanium layer, a nickel layer, and/or a silver layer. The BM layers are covered with a protective coating and a nickel layer is electrolessly deposited over the pads. A diffusion barrier layer is deposited over the nickel layer over the pads, and the protective coating is removed.

In some embodiments, the present disclosure relates to a package assembly having a bump on a first substrate. A molding compound is on the first substrate and contacts sidewalls of the bump. A no-flow underfill layer is on a conductive region of a second substrate. The no-flow underfill layer and the conductive region contact the bump. A mask layer is arranged on the second substrate and laterally surrounds the no-flow underfill layer. The no-flow underfill layer contacts the substrate between the conductive region and the mask layer.

In some embodiments, the present disclosure relates to a package assembly having a bump on a first substrate. A molding compound is on the first substrate and contacts sidewalls of the bump. A no-flow underfill layer is on a conductive region of a second substrate. The no-flow underfill layer and the conductive region contact the bump. A mask layer is arranged on the second substrate and laterally surrounds the no-flow underfill layer. The no-flow underfill layer contacts the substrate between the conductive region and the mask layer.

A semiconductor device includes a semiconductor chip made of a SiC substrate and having main electrodes on one surface and a rear surface, first and second heat sinks, respectively, disposed adjacent to the one surface and the rear surface, a terminal member interposed between the second heat sink and the semiconductor chip, and a plurality of bonding members disposed between the main electrodes, the first and second heat sinks, and the terminal member. The terminal member includes plural types of metal layers symmetrically layered in the plate thickness direction. The terminal member as a whole has a coefficient of linear expansion at least in a direction orthogonal to the plate thickness direction in a range larger than that of the semiconductor chip and smaller than that of the second heat sink.

A semiconductor device includes a semiconductor chip made of a SiC substrate and having main electrodes on one surface and a rear surface, first and second heat sinks, respectively, disposed adjacent to the one surface and the rear surface, a terminal member interposed between the second heat sink and the semiconductor chip, and a plurality of bonding members disposed between the main electrodes, the first and second heat sinks, and the terminal member. The terminal member includes plural types of metal layers symmetrically layered in the plate thickness direction. The terminal member as a whole has a coefficient of linear expansion at least in a direction orthogonal to the plate thickness direction in a range larger than that of the semiconductor chip and smaller than that of the second heat sink.

A semiconductor device has a first semiconductor die and second semiconductor die with a conductive layer formed over the first semiconductor die and second semiconductor die. The second semiconductor die is disposed adjacent to the first semiconductor die with a side surface and the conductive layer of the first semiconductor die contacting a side surface and the conductive layer of the second semiconductor die. An interconnect, such as a conductive material, is formed across a junction between the conductive layers of the first and second semiconductor die. The conductive layer may extend down the side surface of the first semiconductor die and further down the side surface of the second semiconductor die. An extension of the side surface of the first semiconductor die can interlock with a recess of the side surface of the second semiconductor die. The conductive layer extends over the extension and into the recess.

A semiconductor device has a first semiconductor die and second semiconductor die with a conductive layer formed over the first semiconductor die and second semiconductor die. The second semiconductor die is disposed adjacent to the first semiconductor die with a side surface and the conductive layer of the first semiconductor die contacting a side surface and the conductive layer of the second semiconductor die. An interconnect, such as a conductive material, is formed across a junction between the conductive layers of the first and second semiconductor die. The conductive layer may extend down the side surface of the first semiconductor die and further down the side surface of the second semiconductor die. An extension of the side surface of the first semiconductor die can interlock with a recess of the side surface of the second semiconductor die. The conductive layer extends over the extension and into the recess.

A PoP semiconductor device has a top semiconductor package disposed over a bottom semiconductor package. The top semiconductor package has a substrate and a first semiconductor die disposed over the substrate. First and second encapsulants are deposited over the first semiconductor die and substrate. A first build-up interconnect structure is formed over the substrate after depositing the second encapsulant. The top package is disposed over the bottom package. The bottom package has a second semiconductor die and modular interconnect units disposed around the second semiconductor die. A second build-up interconnect structure is formed over the second semiconductor die and modular interconnect unit. The modular interconnect units include a plurality of conductive vias and a plurality of contact pads electrically connected to the conductive vias. The I/O pattern of the build-up interconnect structure on the top semiconductor package is designed to coincide with the I/O pattern of the modular interconnect units.

A PoP semiconductor device has a top semiconductor package disposed over a bottom semiconductor package. The top semiconductor package has a substrate and a first semiconductor die disposed over the substrate. First and second encapsulants are deposited over the first semiconductor die and substrate. A first build-up interconnect structure is formed over the substrate after depositing the second encapsulant. The top package is disposed over the bottom package. The bottom package has a second semiconductor die and modular interconnect units disposed around the second semiconductor die. A second build-up interconnect structure is formed over the second semiconductor die and modular interconnect unit. The modular interconnect units include a plurality of conductive vias and a plurality of contact pads electrically connected to the conductive vias. The I/O pattern of the build-up interconnect structure on the top semiconductor package is designed to coincide with the I/O pattern of the modular interconnect units.