Semiconductor structure and fabrication method thereof
AssigneeUnited Microelectronics Corp.
InventorsTsung-Kai Yu, Chen-Hsiao Wang, Kai-Kuang Ho
Life of this patent
Estimating the term…
Abstract
A semiconductor structure includes a substrate having a bump pad thereon and a passivation layer disposed on the substrate. The passivation layer covers a perimeter of the bump pad and has a slot-shaped opening exposing a central region of the bump pad. An under bump metal (UBM) layer is disposed on the central region of the bump pad. A solder bump is disposed on the UBM layer. The solder bump has a flat top surface area.
Claims20
A semiconductor structure, comprising:
- a substrate having a bump pad thereon;
- a passivation layer disposed on the substrate, wherein the passivation layer covers a perimeter of the bump pad and has a slot-shaped opening exposing a central region of the bump pad;
- an under bump metal (UBM) layer disposed on the central region of the bump pad;
- and
- a solder bump disposed on the UBM layer, wherein the solder bump comprises a flat top surface area.
A method for forming a semiconductor structure, comprising:
- providing a substrate having a bump pad thereon;
- forming a passivation layer on the substrate, wherein the passivation layer covers a perimeter of the bump pad and has a slot-shaped opening exposing a central region of the bump pad;
- forming an under bump metal (UBM) layer on the central region of the bump pad;
- forming a solder bump on the UBM layer;
- subjecting the solder bump to a re-flow process;
- and
- after the re-flow process, pressing the solder bump with a jig at a predetermined temperature thereby forming a flat top surface area on the solder bump.
A semiconductor structure, comprising:
- a substrate having a bump pad thereon;
- a first passivation layer disposed on the substrate, wherein the first passivation layer covers a perimeter of the bump pad and has a first slot-shaped opening exposing a central region of the bump pad;
- a second passivation layer disposed on the first passivation layer, wherein the second passivation layer has a second slot-shaped opening overlapping with the first slot-shaped opening, wherein the second slot-shaped opening has a dimension that is greater than a dimension of the first slot-shaped opening;
- an under bump metal (UBM) layer disposed on the central region of the bump pad;
- and
- a solder bump filled into the first slot-shaped opening and the second slot-shaped opening.
A semiconductor structure, comprising:
- a substrate having a bump pad thereon;
- a passivation layer disposed on the substrate, wherein the passivation layer covers a perimeter of the bump pad and has a slot-shaped opening exposing a central region of the bump pad;
- a first copper layer disposed on the bump pad;
- an annular second copper layer disposed along the perimeter of the bump pad, wherein the annular second copper layer partially overlaps the first copper layer, and wherein an opening is defined by the annular second copper layer;
- and
- a solder bump filled into the opening.
Dependencies are inferred from the claim text.