Semiconductor device capable of preventing solder balls from being removed in reinforcing pad
AssigneeNEC Corporation
InventorKimio Tsunemasu
Life of this patent
Estimating the term…
Abstract
In a semiconductor device having CSP structure, reinforcing pads are provided on corners of the mounting surface of the CSP body portion, and a plurality of solder balls are mounted on the reinforcing pads, respectively. Each of the reinforcing pads has a periphery adjacent to each of the solder balls mounted thereon that is at least semicircular, when seen in plan view. This structure avoids acute angle portions which mechanical stress is concentrated. As a result, peeling of solder balls from the reinforcing pad can be reduced.
Claims7
A semiconductor device having a mounting surface attached to a circuit board, the device comprising:
- plural reinforcing pads on said mounting surface of said semiconductor device that are each adjacent to a respective corner of said mounting surface;
- and
- plural first solder balls on each of said reinforcing pads, each of said plural first solder balls separately attaching the semiconductor device to the circuit board,
- wherein said reinforcing pads each have a respective periphery adjacent to each respective one of said plural first solder balls that, when seen in a plan view of said mounting surface, is at least semicircular.
A semiconductor device having a mounting surface attached to a circuit board, the device comprising:
- plural reinforcing pads on said mounting surface of said semiconductor device that are each adjacent to a respective corner of said mounting surface;
- and
- plural first solder balls on each of said reinforcing pads, each of said plural first solder balls separately attaching the semiconductor device to the circuit board,
- wherein said reinforcing pads each have a respective periphery adjacent to each respective one of said plural first solder balls that has a roundness in line with an outer diameter of said respective first solder ball and that, when seen in a plan view of said mounting surface, is at least semicircular, and
- wherein each of said reinforcing pads is generally X-shaped and has four of said first solder balls thereon, each of said four first solder balls being only at a respective distal end thereof.
A semiconductor device having a mounting surface attached to a circuit board, the device comprising:
- plural reinforcing pads on said mounting surface of said semiconductor device that are each adjacent to a respective corner of said mounting surface;
- and
- plural first solder balls on each of said reinforcing pads, each of said plural first solder balls separately attaching the semiconductor device to the circuit board,
- wherein said reinforcing pads each have a respective periphery adjacent to each respective one of said plural first solder balls that has a roundness in line with an outer diameter of said respective first solder ball and that, when seen in a plan view of said mounting surface, is at least semicircular, and
- wherein each of said reinforcing pads is generally V-shaped and has at least two of said first solder balls thereon, each of said at least two first solder balls being only at a respective distal end thereof.
Dependencies are inferred from the claim text.