Bump structure having a side recess and semiconductor structure including the same
The present disclosure, in some embodiments, relates to a bump structure. The bump structure includes a conductive layer and a solder layer. The solder layer is disposed vertically below and laterally between portions of the conductive layer along a cross-section. The conductive layer is continuous between the portions.
1. A bump structure, comprising:
a conductive layer on a substrate;
a solder layer arranged on the conductive layer; and
wherein the conductive layer has a curved surface that defines a recess within a side of the conductive layer, the solder layer disposed within the recess and covering an entirety of the curved surface as viewed along a cross-sectional view.
2. The bump structure of claim 1 , wherein the conductive layer is asymmetric about a vertical line bisecting the conductive layer.
3. The bump structure of claim 1 , wherein the curved surface defining the recess has a smaller height than the conductive layer.
4. The bump structure of claim 1 , wherein a second side of the conductive layer that opposes the side of the conductive layer does not have a curved surface defining a recess.
5. The bump structure of claim 1 ,
wherein the recess has a first width along a first direction; and
wherein a ratio of the first width to a maximum width of the conductive layer along the first direction is in a range of between about 0.02 and about 0.5.
6. The bump structure of claim 1 , wherein the conductive layer has a smaller height along a vertical direction than the solder layer.
7. The bump structure of claim 1 , wherein the solder layer contacts an outermost sidewall of the conductive layer along a second side of the conductive layer opposing the side of the conductive layer.
8. The bump structure of claim 1 , wherein the conductive layer comprises a metal.
9. A conductive bump structure, comprising:
a conductive layer having one or more surfaces defining a recess along a side of the conductive layer;
a solder material extending from below the conductive layer to within the recess; and
wherein the conductive layer has a greater thickness measured through a center of the conductive layer than along the one or more surfaces defining the recess.
10. The conductive bump structure of claim 9 , wherein the conductive layer laterally surrounds the solder material along a first direction and wherein the solder material is disposed along an outermost sidewall of the conductive layer along a second direction perpendicular to the first direction.
11. The conductive bump structure of claim 9 , wherein the solder material completely fills the recess.
12. The conductive bump structure of claim 9 , wherein the solder material covers an entirety of the one or more surfaces defining the recess along the side of the conductive layer.
13. The conductive bump structure of claim 9 , further comprising:
a conductive trace disposed onto a substrate below the solder material, wherein the solder material couples the conductive trace to the conductive layer.
14. The conductive bump structure of claim 9 , wherein the solder material is asymmetric about a vertical line that extends through a lateral center of the solder material.
15. A bump structure, comprising:
a conductive layer having one or more surfaces that define a recess along a side of the conductive layer;
a solder layer over the conductive layer; and
wherein the solder layer comprises one or more surfaces defining a protrusion that extends outward from a horizontally extending surface of the solder layer facing the conductive layer to within the recess, wherein the protrusion extends to a bottom of the one or more surfaces defining the recess.
16. The bump structure of claim 15 , wherein the conductive layer is asymmetric about a vertical line bisecting the conductive layer.
17. The bump structure of claim 15 , wherein the protrusion has a first side facing the conductive layer and an opposing second side facing away from the conductive layer.
18. The bump structure of claim 15 , wherein the conductive layer continuously extends from a first side of the protrusion to an opposing second side of the protrusion as viewed in a top view of the protrusion.
19. The bump structure of claim 15 , further comprising:
an under-bump metallurgy (UBM) layer disposed over the conductive layer, wherein the protrusion extends from below the conductive layer to the UBM layer.
20. The bump structure of claim 15 , wherein the protrusion is disposed along an outermost surface of the solder layer.