Reliable packaging and interconnect structures
View Patent ↗Methods and apparatus for forming a semiconductor device are provided which may include any number of features. One feature is a method of forming an interconnect structure that results in the interconnect structure having a top surface and portions of the side walls of the interconnect structure covered in a dissimilar material. In some embodiments, the dissimilar material can be a conductive material or a nano-alloy. The interconnect structure can be formed by removing a portion of the interconnect structure, and covering the interconnect structure with the dissimilar material. The interconnect structure can comprise a damascene structure, such as a single or dual damascene structure, or alternatively, can comprise a silicon-through via (TSV) structure.
1. A method of manufacturing a structure comprising a semiconductor device, the method comprising:
forming a first layer on a substrate comprising semiconductor material;
forming a through-hole in the first layer;
forming a first conductive feature in the through-hole, the first conductive feature having a sidewall in the through-hole;
forming a conductive layer on the first conductive feature, the conductive layer overlying the first conductive feature and extending down into the through-hole along the sidewall of the first conductive feature, the conductive layer comprising a material different from any material in the sidewall and top of the first conductive feature;
forming a solder at least on top of the conductive layer, to obtain an interconnect structure for the semiconductor device, the interconnect structure comprising the first conductive feature, the conductive layer, and the solder, wherein the first conductive feature and the conductive layer do not contain solder; and then
removing at least a portion of the first layer to expose at least a portion of a sidewall of the interconnect structure.
2. The method of claim 1 wherein removing at least a portion of the first layer comprises removing the entire first layer.
3. The method of claim 1 wherein the conductive layer covers at least 10% of a length of the sidewall of the first conductive feature.
4. The method of claim 1 wherein the interconnect structure forms at least a top part of a dual damascene structure.
5. The method of claim 1 wherein forming the first conductive feature comprises, before said removing at least a portion of the first layer:
forming a second conductive feature in the through-hole; and then
removing a part of the second conductive feature from a top and sidewall of the second conductive feature.
6. The method of claim 5 wherein removing the part of the second conductive feature comprises:
oxidizing said part of the second conductive feature; and then
removing an oxidized part of the second conductive feature.
7. The method of claim 6 wherein said oxidizing comprises oxidizing, in the through-hole, at least 5% of the sidewall of the second conductive feature.
8. The method of claim 6 wherein removing the oxidized part comprises a wet etch of the oxidized part.
9. The method of claim 5 wherein removing the part of the second conductive feature forms gaps between the sidewall of the second conductive feature and the first layer.
10. The method of claim 1 wherein the first conductive feature comprises copper.
11. The method of claim 1 wherein the first layer is resist.
12. The method of claim 1 wherein the conductive layer comprises a layer of CoP.
13. The method of claim 1 wherein the conductive layer comprises a layer of NiP or a layer of NiW.
14. A semiconductor device comprising:
a substrate comprising a semiconductor material;
an interconnect structure on the substrate, at least a portion of a sidewall of the interconnect structure being exposed, the interconnect structure comprising:
a first conductive feature on the substrate, the first conductive feature having a sidewall;
a conductive layer on the first conductive feature, the conductive layer overlying the first conductive feature and extending down along the sidewall of the first conductive feature, the conductive layer comprising a material different from any material in the sidewall and top of the first conductive feature; and
solder on top of the conductive layer, wherein the first conductive feature and the conductive layer do not contain solder;
wherein at least portions of sidewalls of the conductive layer and of the first conductive feature are exposed.
15. The semiconductor device of claim 14 wherein the conductive layer covers at least 10% of a length of the sidewall of the first conductive feature.
16. The semiconductor device of claim 14 wherein the interconnect structure forms at least a top part of a dual damascene structure.
17. The semiconductor device of claim 14 wherein the first conductive feature comprises copper.
18. The semiconductor device of claim 14 wherein the conductive layer comprises a layer of CoP.
19. The semiconductor device of claim 14 wherein the conductive layer comprises a layer of NiP.
20. The semiconductor device of claim 14 wherein the conductive layer comprises a layer of NiW.