Electronic packages with three-dimensional conductive planes, and methods for fabrication
An electronic package includes an adhesion layer between a first substrate and a second substrate. The adhesion layer is patterned to define openings aligned with through-substrate interconnects and corresponding bond pads. A conductive plane is formed between the first substrate and the second substrate, adjacent to the adhesion layer.
1. An electronic package, comprising:
a first substrate;
a plurality of electrically conductive contact pads disposed on the first substrate;
a second substrate comprising a plurality of through-substrate first vias and a plurality of through-substrate second vias;
a polymeric adhesion layer disposed between and bonding together the first substrate and the second substrate, the adhesion layer having a thickness between the first substrate and the second substrate, and comprising a plurality of openings through the thickness; and
a plurality of electrically conductive first interconnects extending through respective first vias contacting a first lateral edge of the adhesion layer at a gap between the first substrate and the second substrate, disposed against and extending along an underside of the second substrate, and contacting respective contact pads.
2. The electronic package of claim 1 , further comprising an electrically conductive plane extending across a space between the first substrate and the second substrate and contacting a second lateral edge of the adhesion layer at the gap between the first substrate and the second substrate.
3. The electronic package of claim 2 , further comprising a plurality of electrically conductive second interconnects extending through respective second vias, and contacting the conductive plane.
4. The electronic package of claim 1 , wherein at least one of the first substrate and the second substrate comprises a semiconductor material.
5. The electronic package of claim 2 , wherein at least one of the first interconnects extends along a sidewall of the first vias.
6. The electronic package of claim 5 , wherein at least one of the first interconnects connects to the electrically conductive plane in an undercut region of the second substrate.
7. The electronic package of claim 6 , wherein the undercut region includes therein the first lateral edge of the adhesion layer.
8. The electronic package of claim 1 , wherein the polymeric adhesion layer comprises a composition selected from the group consisting of photoresist, epoxy-based photoresist, polyimide, polyparaxylylene, liquid crystal polymer, benzocyclobutene, and SU8.
9. The electronic package of claim 1 , wherein the thickness of the adhesion layer is in a range from 1 to 100 μm.
10. The electronic package of claim 2 , wherein the conductive plane comprises copper.
11. The electronic package of claim 10 , wherein one of the first interconnects is aligned with one of the contact pads.
12. The electronic package of claim 1 , wherein the lateral edge of the adhesion layer is offset from at least one of the first vias.
13. The electronic package of claim 1 , further comprising an electrically conductive plane extending across a space between the first substrate and the second substrate, contacting a second lateral edge of the adhesion layer at the gap between the first substrate and the second substrate, and extending to an outer perimeter of at least one of the first substrate and the second substrate.
14. The electronic package of claim 13 , further comprising a plurality of electrically conductive second interconnects extending through respective second vias, and contacting the conductive plane.
15. The electronic package of claim 14 , wherein at least one of the second interconnects and the conductive plane are connected together along a meandering path crossing the gap between the first and second substrates, disposed at least on the second lateral edge of the adhesion layer, and disposed on an underside of the second substrate.
16. The electronic package of claim 1 , wherein at least one of the first interconnects and at least one of the contact pads are connected together along a meandering path crossing the gap between the first and second substrates, disposed at least on the first lateral edge of the adhesion layer, and disposed on an underside of the second substrate.
17. The electronic package of claim 1 , further comprising an insulator formed on the first substrate.
18. The electronic package of claim 17 , wherein the contact pad is disposed on the insulator and extends to a periphery of the first substrate.
19. The electronic package of claim 1 , wherein the
second substrate comprises a different material than the first substrate.
20. An electronic package, comprising:
a first substrate;
a plurality of electrically conductive contact pads disposed on the first substrate;
a second substrate comprising a plurality of through-substrate first vias and a plurality of through-substrate second vias;
a polymeric adhesion layer disposed between and bonding together the first substrate and the second substrate, the adhesion layer having a thickness between the first substrate and the second substrate, and comprising a plurality of openings through the thickness; and
a plurality of electrically conductive first interconnects extending through respective first vias contacting a first lateral edge of the adhesion layer at a gap between the first substrate and the second substrate, disposed on an underside of the second substrate, and contacting respective contact pads; and
an electrically conductive plane extending across a space between the first substrate and the second substrate and contacting a second lateral edge of the adhesion layer at the gap between the first substrate and the second substrate.