Semiconductor device and method of forming an interconnect structure for 3-D devices using encapsulant for structural support

1. A method of making a semiconductor device, comprising:

providing a substrate;

forming a first interconnect structure, including a plurality of conductive pillars, over a first surface of the substrate;

disposing a semiconductor die over the first interconnect structure with bumps electrically connected to the conductive pillars;

depositing an encapsulant over the semiconductor die and first interconnect structure;

forming a via through a second surface of the substrate, opposite the first surface of the substrate, to the first interconnect structure; and

forming a second interconnect structure in the via.

2. The method of claim 1 , wherein forming the second interconnect structure includes:

applying an insulating layer over a sidewall of the via; and

forming a conductive layer over the insulating layer in the via.

3. The method of claim 1 , wherein the via includes a tapered sidewall.

4. The method of claim 1 , wherein forming the first interconnect structure includes:

forming a first conductive layer over the first surface of the substrate;

forming a first insulating layer over the first conductive layer and substrate;

forming a second conductive layer over the first insulating layer and first conductive layer;

forming a second insulating layer over the second conductive layer and first insulating layer;

forming a conductive pillar over the second conductive layer;

forming a third insulating layer around the conductive pillar; and

forming a third conductive layer over the conductive pillar and electrically connecting the third conductive layer to the semiconductor die.

5. The method of claim 1 , wherein forming the second interconnect structure further includes forming a bump in the via over the first interconnect structure.

6. The method of claim 1 , further including mounting the semiconductor device to a printed circuit board through the second interconnect structure.

7. The method of claim 1 , wherein forming the second interconnect structure includes:

forming an insulating layer over the first interconnect structure; and

forming a bump over the first interconnect structure.

8. A method of making a semiconductor device, comprising:

providing a substrate;

forming a first interconnect structure, including a plurality of conductive pillars, over a first surface of the substrate;

disposing a semiconductor die over the first interconnect structure with bumps electrically connected to the conductive pillars;

depositing an encapsulant over the semiconductor die and first interconnect structure;

forming a via through a second surface of the substrate, opposite the first surface of the substrate, to the first interconnect structure; and

forming a first conductive layer in the via.

9. The method of claim 8 , further including forming a second interconnect structure over the first conductive layer.

10. The method of claim 9 , wherein forming the second interconnect structure includes forming a bump in the via over the first conductive layer.

11. The method of claim 8 , wherein the via includes a tapered sidewall.

12. The method of claim 8 , further including removing a portion of the substrate to reduce a thickness of the substrate.

13. The method of claim 8 , wherein forming the first interconnect structure includes:

forming a second conductive layer over the first surface of the substrate;

forming a first insulating layer over the second conductive layer and substrate;

forming a third conductive layer over the first insulating layer and second conductive layer;

forming a second insulating layer over the third conductive layer and first insulating layer;

forming a conductive pillar over the third conductive layer;

forming a third insulating layer around the conductive pillar; and

forming a fourth conductive layer over the conductive pillar and electrically connecting the third conductive layer to the semiconductor die.

14. The method of claim 8 , further including forming an insulating layer over a sidewall of the via.

15. A method of making a semiconductor device, comprising:

providing a substrate;

forming a first interconnect structure, including a plurality of conductive pillars, over a first surface of the substrate;

disposing a semiconductor die over the first interconnect structure;

depositing an encapsulant over the semiconductor die and first interconnect structure;

forming a via through a second surface of the substrate, opposite the first surface of the substrate, to the first interconnect structure; and

forming a first conductive layer over a sidewall of the via.

16. The method of claim 15 , further including forming an insulating layer over the sidewall of the via.

17. The method of claim 15 , further including forming a second interconnect structure over the first conductive layer.

18. The method of claim 17 , wherein forming the second interconnect structure includes forming a bump in the via over the first conductive layer.

19. The method of claim 15 , further including removing a portion of the substrate to reduce a thickness of the substrate.

20. The method of claim 15 , wherein forming the first interconnect structure includes:

forming a second conductive layer over the first surface of the substrate;

forming a first insulating layer over the second conductive layer and substrate;

forming a third conductive layer over the first insulating layer and second conductive layer;

forming a second insulating layer over the third conductive layer and first insulating layer;

forming a conductive pillar over the third conductive layer;

forming a third insulating layer around the conductive pillar; and

forming a fourth conductive layer over the conductive pillar and electrically connecting the fourth conductive layer to the semiconductor die.

21. A method of making a semiconductor device, comprising:

providing a substrate;

forming a first interconnect structure over a first surface of the substrate;

disposing a semiconductor die over the first interconnect structure;

depositing an encapsulant over the semiconductor die and extending to the substrate;

forming an opening in the substrate extending to the first interconnect structure; and

forming a second interconnect structure over the substrate and into the opening in the substrate to contact the first interconnect structure.

22. The method of claim 21 , wherein forming the first interconnect structure includes:

forming a first conductive layer over the first surface of the substrate;

forming a first insulating layer over the first conductive layer and substrate;

forming a second conductive layer over the first insulating layer and first conductive layer;

forming a second insulating layer over the second conductive layer and first insulating layer;

forming a conductive pillar over the second conductive layer;

forming a third insulating layer around the conductive pillar; and

forming a third conductive layer over the conductive pillar and electrically connecting the third conductive layer to the semiconductor die.

23. The method of claim 21 , wherein forming the second interconnect structure includes:

forming an insulating layer over the first interconnect structure; and

forming a bump over the first interconnect structure.