Offset test pads for WLCSP final test
View Patent ↗A device configured for WLCSP, can include: a first pad; a test pad offset from the first pad; a first RDL path that connects the first pad to the test pad; and a second RDL path that connects the test pad to a solder ball. In another case, a device configured for WLCSP can include: a first pad; a test pad offset from the first pad; a first RDL path that connects the first pad to a solder ball; and a second RDL path that connects the test pad to the solder ball. A wafer having devices configured for WLCSP, can include: a first device having a first pad; a second device having a test pad; a first RDL path that connects the first pad to a solder ball; and a second RDL path that connects the test pad to the solder ball.
1. A device configured for wafer level chip scale packaging (WLCSP), the device comprising:
a) a first pad;
b) a test pad offset from the first pad;
c) a first redistribution layer (RDL) path that connects the first pad to the test pad with no other pad connections therebetween; and
d) a second RDL path that connects the test pad to a solder ball.
2. The device of claim 1 , wherein the device comprises a serial non-volatile memory (NVM) device.
3. The device of claim 1 , wherein the first and second RDL paths are in a same layer.
4. The device of claim 1 , wherein the first and second RDL paths are in different layers.
5. The device of claim 1 , further comprising a polymer layer that fully covers the first pad, and leaves a portion of the test pad exposed.
6. The device of claim 1 , wherein the device further comprises:
a) a plurality of the first pads; and
b) a plurality of the test pads, where each of the plurality of the test pads is offset from a corresponding of the plurality of the first pads by a same offset length.
7. A device configured for WLCSP, the device comprising:
a) a first pad;
b) a test pad offset from the first pad;
c) a first RDL path that connects the first pad to a solder ball; and
d) a second RDL path that connects the test pad to the solder ball,
e) wherein a length of the offset is substantially greater than a diameter of the solder ball.
8. The device of claim 7 , wherein the device comprises a serial NVM device.
9. The device of claim 7 , wherein the first and second RDL paths are in a same layer.
10. The device of claim 7 , wherein the first and second RDL paths are in different layers.
11. The device of claim 7 , further comprising a polymer layer that fully covers the first pad, and leaves a portion of the test pad exposed.
12. The device of claim 7 , wherein the device further comprises:
a) a plurality of the first pads; and
b) a plurality of the test pads, where each of the plurality of the test pads is offset from a corresponding of the plurality of the first pads by a same offset length.
13. A wafer comprising the device of claim 7 , the wafer comprising:
a) a first semiconductor device comprising the first pad; and
b) a second semiconductor device comprising the test pad.
14. The wafer of claim 13 , wherein each of the first and second semiconductor devices comprises a serial NVM device.
15. A device configured for WLCSP, the device comprising:
a) a first pad;
b) a test pad offset from the first pad;
c) a first RDL path that connects the first pad to a solder ball; and
d) a second RDL path that connects the test pad to the solder ball,
e) wherein a length of the offset is about a diameter of the solder ball.
16. The device of claim 15 , wherein the device comprises a serial NVM device.
17. The device of claim 15 , wherein the first and second RDL paths are in a same layer.
18. The device of claim 15 , wherein the first and second RDL paths are in different layers.
19. The device of claim 15 , further comprising a polymer layer that fully covers the first pad, and leaves a portion of the test pad exposed.
20. The device of claim 15 , wherein the device further comprises:
a) a plurality of the first pads; and
b) a plurality of the test pads, where each of the plurality of the test pads is offset from a corresponding of the plurality of the first pads by a same offset length.