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, wherein the trench comprises a first trench portion and a second trench portion laterally separated from the first trench portion in a cross-sectional view such that a part of the substrate is interposed between the first trench portion and the second trench portion; and
a conductive material disposed within the trench;
a recessed region disposed extending from the second major surface inward to a second distance, wherein the recessed region is wider than the conductive via structure;
a first conductive region disposed extending along a first sidewall surface of the recessed region in the cross-sectional view, wherein the first conductive region terminates within the recessed region without extending along a second sidewall surface of the recessed region opposite to the first sidewall surface in the cross-sectional view, and wherein the first conductive region is physically coupled to the conductive material and is further disposed along at least a portion of the second major surface outside of the recessed region;
an insulating layer disposed between first conductive region and the substrate within the recessed region, wherein a portion of the insulating layer is disposed adjacent the part of the substrate interposed between the first trench portion and the second trench portion;
a protective layer disposed over a first portion of the first conductive region such that the protective layer is disposed within the recessed region without filling the recessed region, wherein a second portion of the first conductive region outside of the recessed region is devoid of the protective layer; and
a conductive bump conductively attached to the second portion of the first conductive region outside of the recessed region.
2. The structure of claim 1 , wherein:
the second distance is greater than the first distance;
the first distance is in a range from about 10 microns through about 30 microns; and
the through-substrate via structure comprises an interposer structure.
3. The structure of claim 1 , wherein the conductive material comprises tungsten, and wherein the substrate has a thickness greater than 200 microns.
4. The structure of claim 1 , wherein the first conductive region has a thickness greater than 100 nanometers (nm).
5. The structure of claim 1 , wherein the substrate has at least one side 15 millimeters in length, and wherein the substrate has a thickness greater than or equal to 250 microns.
6. The structure of claim 1 , wherein the first conductive region protrudes outward from the recessed region and outward from the second major surface.
7. The structure of claim 1 , wherein the sidewall surface of the recessed region comprises a sloped shape.
8. 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, wherein the trench comprises a first trench portion and a second trench portion laterally separated from the first trench portion in a cross-sectional view such that a part of the substrate is interposed between the first trench portion and the second trench portion;
an insulating structure disposed along a sidewall surface of the trench; and
a conductive material disposed adjacent 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 disposed extending along a sidewall surface of the recessed region in the cross-sectional view, wherein the first conductive region terminates within the recessed region without extending along a second sidewall surface of the recessed region opposite to the first sidewall surface in the cross-sectional view, and wherein the first conductive region is electrically coupled to the conductive material, and wherein the conductive material and the first conductive region comprise different materials; and
an insulating layer disposed between first conductive region and the substrate within the recessed region, wherein:
the first conductive region is physically and electrically coupled to the conductive material through openings in the insulating layer; and
a portion of the insulating layer is disposed adjacent the part of the substrate interposed between the first trench portion and the second trench portion.
9. The structure of claim 8 , wherein:
the first distance is in a range from about 10 microns through about 30 microns;
the through-substrate via structure comprises an interposer structure;
the conductive material comprises tungsten;
the substrate has a thickness greater than 200 microns;
the first conductive region is further disposed along at least a portion of the second major surface; and
the first conductive region is physically affixed to the conductive material.
10. The structure of claim 8 , wherein:
the first conductive region is further disposed along at least a portion of the second major surface outside of the recessed region; and
the structure further comprises:
a protective layer disposed over a first portion of the first conductive region such that the protective layer is disposed within the recessed region without filling the recessed region, wherein a second portion of the first conductive region outside of the recessed region is devoid of the protective layer; and
a conductive bump conductively attached to the second portion of the first conductive region outside of the recessed region.
11. 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 inward from the first major surface to a first distance, wherein the trench comprises a first trench portion and a second trench portion laterally separated from the first trench portion in a cross-sectional view such that a part of the substrate is interposed between the first trench portion and the second trench portion; and
a conductive material disposed within the trench, wherein the conductive material comprises tungsten;
a recessed region disposed extending from the second major surface inward to a second distance, wherein the recessed region is wider than the conductive via structure, and wherein the second distance is greater than the first distance; and
a first conductive region disposed extending along a first sidewall surface of the recessed region in the cross-sectional view, wherein the first conductive region terminates within the recessed region without extending along a second sidewall surface of the recessed region opposite to the first sidewall surface in the cross-sectional view, and wherein the first conductive region is physically coupled to the conductive material and is further disposed along at least a portion of the second major surface outside of the recessed region;
an insulating layer disposed between first conductive region and the substrate within the recessed region, wherein a portion of the insulating layer is disposed adjacent the part of the substrate interposed between the first trench portion and the second trench portion;
a protective layer disposed over a first portion of the first conductive region such that the protective layer is disposed within the recessed region without filling the recessed region, wherein a second portion of the first conductive region outside of the recessed region is devoid of the protective layer; and
a conductive bump conductively attached to the second portion of the first conductive region outside of the recessed region.
12. The structure of claim 11 , wherein the first conductive region has a thickness greater than 100 nanometers (nm).
13. The structure of claim 11 , wherein the first conductive region protrudes outward from the recessed region and outward from the second major surface.
14. The structure of claim 11 , wherein the substrate has a thickness greater than or equal to 250 microns.
15. The structure of claim 11 , wherein:
the first distance is in a range from about 10 microns through about 30 microns.