The present application discloses a method for fabricating a semiconductor device with liners. The method includes providing a substrate having a first surface and a second surface opposite to the first surface, inwardly forming a trench on the first surface of the substrate, forming a plurality of liners positioned on side surfaces of the trench, forming a first insulating segment filling the trench, and removing part of the substrate from the second surface to expose the first insulating segment and the plurality of liners.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first semiconductor structure and a first connecting structure, wherein the first connecting structure includes a first connecting insulating layer positioned on the first semiconductor structure, two first conductive layers positioned in the first connecting insulating layer, and a first porous layer positioned between the two first conductive layers. A porosity of the first porous layer is between about 25% and about 100%.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first semiconductor structure and a first connecting structure, wherein the first connecting structure includes a first connecting insulating layer positioned on the first semiconductor structure, two first conductive layers positioned in the first connecting insulating layer, and a first porous layer positioned between the two first conductive layers. A porosity of the first porous layer is between about 25% and about 100%.

Various semiconductor chips and packages are disclosed. In one aspect, an apparatus is provided that includes a semiconductor chip that has a side, and plural conductive pillars on the side. Each of the conductive pillars includes a pillar portion that has an exposed shoulder facing away from the semiconductor chip. The shoulder provides a wetting surface to attract melted solder. The pillar portion has a first lateral dimension at the shoulder. A solder cap is positioned on the pillar portion. The solder cap has a second lateral dimension smaller than the first lateral dimension.

Various semiconductor chips and packages are disclosed. In one aspect, an apparatus is provided that includes a semiconductor chip that has a side, and plural conductive pillars on the side. Each of the conductive pillars includes a pillar portion that has an exposed shoulder facing away from the semiconductor chip. The shoulder provides a wetting surface to attract melted solder. The pillar portion has a first lateral dimension at the shoulder. A solder cap is positioned on the pillar portion. The solder cap has a second lateral dimension smaller than the first lateral dimension.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first semiconductor structure, a first connecting structure, and a second semiconductor structure positioned on the first connecting structure. The first connecting structure includes a first connecting insulating layer positioned on the first semiconductor structure, two first conductive layers positioned in the first connecting insulating layer, and a first porous layer positioned between the two first conductive layers. The second semiconductor structure is positioned on the first connecting structure and includes two second conductive features positioned on the two first conductive layers. The first conductive layer has a first width, the second conductive feature has a second width greater than the first width, and the different width forms a step-shaped cross-sectional profile near an interface of the first conductive layer and the second conductive feature.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first semiconductor structure, a first connecting structure, and a second semiconductor structure positioned on the first connecting structure. The first connecting structure includes a first connecting insulating layer positioned on the first semiconductor structure, two first conductive layers positioned in the first connecting insulating layer, and a first porous layer positioned between the two first conductive layers. The second semiconductor structure is positioned on the first connecting structure and includes two second conductive features positioned on the two first conductive layers. The first conductive layer has a first width, the second conductive feature has a second width greater than the first width, and the different width forms a step-shaped cross-sectional profile near an interface of the first conductive layer and the second conductive feature.

Rework and recovery processes generally include application of liquid metal etchant compositions to selectively remove one layer at a time of a solder layer and underball metallurgy multilayer stack including a titanium-based adhesion layer, a copper seed layer, a plated copper conductor layer, and a nickel-based barrier layer. The rework and recovery process can be applied to the dies, wafers, and/or substrate.

Rework and recovery processes generally include application of liquid metal etchant compositions to selectively remove one layer at a time of a solder layer and underball metallurgy multilayer stack including a titanium-based adhesion layer, a copper seed layer, a plated copper conductor layer, and a nickel-based barrier layer. The rework and recovery process can be applied to the dies, wafers, and/or substrate.

The present application discloses a semiconductor device and a method for fabricating the semiconductor device. The semiconductor device includes a first semiconductor structure, a first connecting structure, and a second semiconductor structure positioned on the first connecting structure. The first connecting structure includes a first connecting insulating layer positioned on the first semiconductor structure, two first conductive layers positioned in the first connecting insulating layer, and a first porous layer positioned between the two first conductive layers. The second semiconductor structure is positioned on the first connecting structure and includes two second conductive features positioned on the two first conductive layers. The first conductive layer has a first width, the second conductive feature has a second width greater than the first width, and the different width forms a step-shaped cross-sectional profile near an interface of the first conductive layer and the second conductive feature.