Through-substrate via structure and method of manufacture
A through-substrate vias structure includes a substrate having opposing first and second major surfaces. One or more conductive via structures are disposed extending from the first major surface to a first vertical distance within the substrate. A recessed region extends from the second major surface to a second vertical distance within the substrate and adjoining a lower surface of the conductive via. In one embodiment, the second vertical distance is greater than the first vertical distance. A conductive region is disposed within the recessed region and is configured to be in electrical and/or thermal communication with the conductive via.
1. A through-substrate via structure comprising:
a substrate having a first major surface and a second major surface opposite to the first major surface;
a conductive via structure comprising:
a trench extending from the first major surface to a first distance into the substrate; and
a conductive material disposed within the trench;
a recessed region disposed extending from the second major surface into the substrate to a second distance, wherein at least a portion of the recessed region is wider than the conductive via structure;
a first conductive region within the recessed region; and
an insulating layer disposed between the first conductive region and the substrate within the recessed region, wherein:
the insulating layer extends outside of the recessed region and overlaps the second major surface;
the insulating layer comprises an outer surface distal to and overlapping the second major surface outside of the recessed region;
the first conductive region comprises:
a conductive-fill structure disposed within the recessed region so as to laterally extend between opposing sidewalls of the recessed region in a cross-sectional view, the conductive-fill structure having an outermost surface distal to the conductive via structure; and
a solder structure disposed adjacent to the outermost surface of the conductive-fill structure, the solder structure extending outside of the recessed region such that a distal end portion of the solder structure protrudes outward with respect to the outer surface of the insulating layer;
the solder structure has a proximate end portion opposite to the distal end portion, the proximate end portion directly adjoining the outermost surface of the conductive-fill structure;
the outermost surface of the conductive-fill structure is a major surface that is substantially coplanar with the outer surface of the insulating layer; and
the proximate end portion is disposed outside of the recessed region such that side portions of the solder structure are devoid of the conductive-fill structure.
2. The structure of claim 1 , wherein:
the conductive-fill structure substantially fills the recessed region and is other than a conductive liner.
3. The structure of claim 1 , wherein:
the insulating layer comprises an opening that exposes the conductive material;
the conductive-fill structure extends into the opening and is physically and electrically coupled to the conductive material through the opening; and
the conductive-fill structure physically contacts the conductive material at an interface defined by the substrate and the insulating layer.
4. The structure of claim 1 , wherein:
the solder structure overlaps the recessed region; and
the conductive-fill structure comprises copper.
5. The structure of claim 1 , wherein:
the first conductive region is electrically isolated from the conductive material.
6. The structure of claim 1 , wherein:
the first distance is less than about 50 microns;
the second distance is greater than or equal to 150 microns; and
the through-substrate via structure comprises an interposer structure.
7. The structure of claim 1 , wherein the conductive material comprises tungsten.
8. The structure of claim 1 , wherein the insulating layer comprises a polymer.
9. The structure of claim 1 , wherein the substrate comprises an insulating material.
10. A through-substrate via structure comprising:
a substrate having a first major surface and a second major surface opposite to the first major surface;
a conductive via structure comprising:
a trench extending from the first major surface to a first distance;
an insulating structure disposed along a sidewall surface of the trench; and
a conductive material disposed adjacent to the insulating structure within the trench;
a recessed region disposed extending from the second major surface inward to a second distance, wherein the second distance is greater than the first distance;
a first conductive region coupled to the recessed region; and
an insulating layer disposed between the first conductive region and the substrate within the recessed region, wherein:
the insulating layer comprises an opening that exposes the conductive material;
the insulating layer extends outside of the recessed region and overlaps the second major surface;
the insulating layer comprises an outer surface distal to and overlapping the second major surface outside of the recessed region;
the first conductive region comprises:
a conductive-fill structure disposed within the recessed region so as to laterally extend between opposing sidewalls of the recessed region in a cross-sectional view, the conductive-fill structure having an outermost surface that is distal to the conductive via structure; and
a conductive structure disposed adjacent to the outermost surface of the conductive-fill structure, the conductive structure extending outside of the recessed region such that a distal end portion of the conductive structure protrudes outward with respect to the outer surface of the insulating layer; and
the conductive-fill structure extends into the opening and physically contacts the conductive material at an interface defined by the substrate and the insulating layer.
11. The structure of claim 10 , wherein:
the conductive structure comprises a solder bump;
the first distance is less than about 50 microns; and
the second distance is greater than or equal to about 150 microns.
12. The structure of claim 10 , wherein:
the outermost surface of the conductive-fill structure is substantially coplanar with the outer surface of the insulating layer; and
the conductive structure is directly attached to the outermost surface of the conductive-fill structure.
13. The structure of claim 10 , wherein:
the conductive structure comprises a proximate end portion opposite to the distal end portion and a side surface portion extending between the distal end portion and the proximate end portion;
the side surface portion is devoid of the conductive-fill structure; and
the conductive structure overlaps the recessed region.
14. The structure of claim 10 , wherein:
the conductive material comprises tungsten.
15. The structure of claim 10 , wherein:
the through-substrate via structure comprises an interposer having at least one side with a width of at least 15 millimeters.
16. A through-substrate via structure comprising:
a substrate having a first major surface and a second major surface opposite to the first major surface;
a conductive via structure comprising:
a trench extending from the first major surface to a first distance; and
a conductive material comprising tungsten disposed within the trench;
a recessed region disposed extending from the second major surface inward to a second distance, wherein at least a portion of the recessed region is wider than the conductive via structure;
a first conductive region in the recessed region; and
an insulating layer disposed between the first conductive region and the substrate within the recessed region, wherein:
the insulating layer comprises an opening that exposes the conductive material;
the insulating layer extends outside of the recessed region and overlaps the second major surface;
the insulating layer comprises an outer surface distal to and overlapping the second major surface outside of the recessed region;
the first conductive region comprises:
a conductive-fill structure disposed within the recessed region so as to laterally extend between opposing sidewalls of the recessed region in a cross-sectional view, wherein:
the conductive-fill structure comprises an outermost surface distal to the conductive via structure,
the conductive-fill structure physically contacts the insulating layer; and
the outermost surface of the conductive-fill structure comprises a major surface that is substantially coplanar with the outer surface of the insulating layer;
a conductive bump disposed adjacent to the outermost surface of the conductive-fill structure, the conductive bump extending outside of the recessed region such that a distal end portion of the conductive bump protrudes outward with respect to the outer surface of the insulating layer;
the conductive bump further comprises a proximate end portion that adjoins the outermost surface of the conductive-fill structure and a side surface portion that connects the distal end portion to the proximate end portion; and
the side surface portion is devoid of the conductive-fill structure.
17. The structure of claim 16 , wherein:
the conductive bump comprises a solder material;
the first distance is less than or equal to about 50 microns; and
the second distance is greater than or equal to about 150 microns.
18. The structure of claim 16 , wherein:
the conductive-fill structure extends into the opening and is physically and electrically coupled to the conductive material through the opening at an interface defined by the insulating layer and the substrate.
19. The structure of claim 16 , wherein:
the conductive bump overlaps the recessed region; and
the conductive-fill structure comprises copper.
20. The structure of claim 16 , wherein:
the through-substrate via structure comprises an interposer having at least one side with a width of at least 15 millimeters.