Solder pad for semiconductor device package
View Patent ↗A solder ball pad for mounting a solder ball of a semiconductor device for preventing delamination of an overlying dielectric layer, and particularly devices and methods providing improved solder ball pad structures in a device such as a semiconductor device package.
1. A semiconductor device package, comprising:
a solder ball pad formed on a first dielectric layer, the solder ball pad having a central pad portion, a perimeter, and an edge about the perimeter, the central pad portion defining and encircling a solder ball mounting area situated inward from the edge about the perimeter, and a recessed portion within the central pad portion at an end of the solder ball pad; and
a second dielectric layer formed over the solder ball pad including the perimeter, edge and the central pad portion encircling the solder ball mounting area;
wherein
the perimeter of the solder ball pad comprises a plurality of outwardly extending protrusions extending about the perimeter up to the recessed portion, the protrusions configured to lock the solder ball pad including the edge and the central pad portion encircling the solder ball mounting area to the second dielectric layer to inhibit delamination of the second dielectric layer therefrom, including at least a first protrusion and a second protrusion adjacent to the first protrusion, the first protrusion and the second protrusion spaced apart at a distance to confine delamination of the second dielectric layer from the solder ball pad to an area between the first protrusion and the second protrusion, each of the protrusions having a first surface, a second surface and a distal end, wherein the distal ends of each of the protrusions are not interconnected to each other; and
the second dielectric layer completely covers the plurality of protrusions, the entire perimeter of the solder ball pad including the edge, and the central pad portion of the solder ball pad encircling the solder ball mounting area but not the solder ball mounting area.
2. The semiconductor device package of claim 1 , wherein the plurality of protrusions each have opposing sides, a distal end, and a protrusion length, and the protrusion length is effective to limit a delamination to one side and prior to the distal end.
3. The semiconductor device package of claim 1 , wherein the protrusion length is about 10-100 μm.
4. The semiconductor device package of claim 1 , wherein the solder ball pad has a thickness of about 2 μm to less than 10 μm, and the protrusion length is about 10-75 μm.
5. The semiconductor device package of claim 1 , wherein the solder ball pad has a thickness of about 10-20 μm, and the protrusion length is about 25-100 μm.
6. The semiconductor device package of claim 1 , wherein the solder ball pad further comprises one or more through-holes situated along the perimeter and extending through the solder ball pad to the first dielectric layer, and the one or more through-holes are filled with the second dielectric layer.
7. The semiconductor device package of claim 6 , wherein the through-holes have a diameter of about 10-80 μm.
8. The semiconductor device package of claim 6 , wherein the solder ball pad has a thickness of about 2 μm to less than 10 μm, and the diameter of the through-holes is about 10-60 μm.
9. The semiconductor device package of claim 6 , wherein the solder ball pad has a thickness of about 10-20 μm, and the diameter of the through-holes is about 20-80 μm.
10. A method of making a semiconductor device package, the method comprising:
forming a solder ball pad on a first dielectric layer, the solder ball pad having a central pad portion, a perimeter, and an edge about the perimeter, the central pad portion defining and encircling a solder ball mounting area situated inward from the edge about the perimeter, and a recessed portion within the central pad portion at an end of the solder ball pad; and
forming a second dielectric layer over the solder ball pad including the perimeter, edge and the central pad portion encircling the solder ball mounting area;
wherein
said forming the solder ball pad comprises forming a locking feature comprising one or more features configured to lock the solder ball pad including the edge and the central pad portion encircling the solder ball mounting area to the second dielectric layer to inhibit delamination of the second dielectric layer from the solder ball pad; the locking feature comprising a plurality of outwardly extending protrusions extending about the perimeter up to the recessed portion, the protrusions including at least a first protrusion and a second protrusion adjacent to the first protrusion; the first protrusion and the second protrusion spaced apart at a distance so as to confine delamination of the second dielectric layer from the solder ball pad to an area between the first protrusion and the second protrusion, each of the protrusions having a first surface, a second surface and a distal end, wherein the distal ends of each of the protrusions are not interconnected to each other; and
the second dielectric layer completely covers the plurality of protrusions, the entire perimeter of the solder ball pad including the edge, and the central pad portion of the solder ball pad encircling the solder ball mounting area but not the solder ball mounting area.
11. The method of claim 10 , wherein forming the locking feature further comprises forming through-holes extending through the solder ball pad to the first dielectric layer, and forming the second dielectric layer comprises filling the through-holes with the second dielectric layer.
12. The method of claim 11 , wherein the locking feature comprises a plurality of through-holes along the perimeter of the solder ball pad.
13. The method of claim 10 , further comprising:
forming a multi-layer circuit interconnect on a semiconductor die; and
forming the first dielectric layer over the multi-layer circuit interconnect.
14. A semiconductor device package, comprising:
a solder ball pad formed on a first dielectric layer, the solder ball pad having a central pad portion, a perimeter, and an edge about the perimeter, the central pad portion defining and encircling a solder ball mounting area situated inward from the edge about the perimeter, and a recessed portion within the central pad portion at an end of the solder ball pad; and
a second dielectric layer formed over the solder ball pad including the perimeter, edge and the central pad portion encircling the solder ball mounting area;
wherein
the perimeter of the solder ball pad comprises a plurality of through-holes extending through the solder ball pad to the first dielectric layer and a plurality of outwardly extending protrusions, the protrusions extending about the perimeter up to the recessed portion and configured to lock the solder ball pad including the edge and the central pad portion encircling the solder ball mounting area to the second dielectric layer to inhibit delamination of the second dielectric layer therefrom, including at least a first protrusion and a second protrusion adjacent to the first protrusion, the first protrusion and the second protrusion spaced apart at a distance to confine delamination of the second dielectric layer from the solder ball pad to an area between the first protrusion and the second protrusion, each of the protrusions having a first surface, a second surface and a distal end, wherein the distal ends of each of the protrusions are not interconnected to each other, and the plurality of through-holes situated on the central pad portion between the edge about the perimeter and the solder ball mounting area; and
the second dielectric layer completely covers the plurality of protrusions, the entire perimeter of the solder ball pad including the edge, and the central pad portion of the solder ball pad encircling the solder ball mounting area but not the solder ball mounting area, and fills the plurality of through-holes.
15. A method of making a semiconductor device package, the method comprising:
forming a solder ball pad on a first dielectric layer, the solder ball pad having a central pad portion, a perimeter, and an edge about the perimeter, the central pad portion defining and encircling a solder ball mounting area situated inward from the edge about the perimeter, and a recessed portion within the central pad portion at an end of the solder ball pad; and
forming a second dielectric layer over the solder ball pad including the perimeter, edge and the central pad portion encircling the solder ball mounting area;
wherein
said forming the solder ball pad comprises forming a locking feature comprising one or more features configured to lock the solder ball pad including the edge and the central pad portion encircling the solder ball mounting area to the second dielectric layer to inhibit delamination of the second dielectric layer from the solder ball pad;
the locking feature comprising a plurality of through-holes extending through the solder ball pad to the first dielectric layer and a plurality of outwardly extending protrusions, the protrusions extending about the perimeter up to the recessed portion and including at least a first protrusion and a second protrusion adjacent to the first protrusion; the first protrusion and the second protrusion spaced apart at a distance so as to confine delamination of the second dielectric layer from the solder ball pad to an area between the first protrusion and the second protrusion, each of the protrusions having a first surface, a second surface and a distal end, wherein the distal ends of each of the protrusions are not interconnected to each other protrusions; and
the second dielectric layer completely covers the plurality of protrusions, the entire perimeter of the solder ball pad including the edge, and the central pad portion of the solder ball pad encircling the solder ball mounting area but not the solder ball mounting area, and fills the through-holes of the locking feature.