Semiconductor device and method of forming conductive posts embedded in photosensitive encapsulant

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

providing a post carrier including a base plate and a plurality of conductive posts;

forming a photosensitive encapsulant on the base plate of the post carrier to surround the conductive posts;

after forming the photosensitive encapsulant on the base plate, etching the photosensitive encapsulant to expose a portion of the base plate;

mounting a semiconductor die to the exposed portion of the base plate such that upper surfaces of the conductive posts are disposed above an upper surface of the semiconductor die;

depositing a second encapsulant over the semiconductor die;

forming a first circuit build-up layer over the second encapsulant, the first circuit build-up layer being electrically connected to the conductive posts;

removing the base plate of the post carrier; and

after removing the base plate, forming a second circuit build-up layer under the semiconductor die and the photosensitive encapsulant opposite the first circuit build-up layer, the second circuit build-up layer being electrically connected to the conductive posts.

2. The method of claim 1 , including connecting an electrical interconnect structure to the second circuit build-up layer.

3. The method of claim 1 , wherein the photosensitive encapsulant includes benzocyclobutene (BCB), polyimide (PI) or polymethylmethacrylate (PMMA).

4. The method of claim 1 , including planarizing the second encapsulant using chemical etching, or mechanical grinding.

5. The method of claim 4 , wherein planarizing the second encapsulant exposes a top surface of the conductive posts and the semiconductor die.

6. The method of claim 1 , including arranging the conductive posts in a rectangular form around the base plate of the post carrier.

7. The method of claim 1 , wherein the post carrier is prefabricated.

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

providing a post carrier including a base plate and plurality of conductive posts;

forming a photosensitive encapsulant on the base plate of the post carrier to surround the conductive posts;

after forming the photosensitive encapsulant on the base plate, etching the photosensitive encapsulant to expose a portion of the base plate of the post carrier;

mounting a semiconductor die to the portion of the base plate such that an upper surface of the semiconductor die is disposed below upper surfaces of the conductive posts; and

forming a first build-up layer over a first side of the photosensitive encapsulant, the first build-up layer being electrically connected to the conductive posts.

9. The method of claim 8 , including removing the base plate of the post carrier.

10. The method of claim 9 , including forming a second build-up layer over a second side of the photosensitive encapsulant opposite the first build-up layer, the second build-up layer being electrically connected to the conductive posts.

11. The method of claim 8 , including depositing a second encapsulant over the semiconductor die.

12. The method of claim 8 , further including arranging the conductive posts in a rectangular form around the base plate of the post carrier.

13. The method of claim 8 , wherein the post carrier is prefabricated.

14. The method of claim 8 , wherein the photosensitive encapsulant includes benzocyclobutene (BCB), polyimide (PI) or polymethylmethacrylate (PMMA).

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

providing a post carrier including a base plate and plurality of conductive posts;

forming a photosensitive encapsulant on the base plate of the post carrier to surround the conductive posts;

after forming the photosensitive encapsulant on the base place, etching the photosensitive encapsulant to expose a portion of the base plate of the post carrier;

mounting a semiconductor die to the exposed portion of the base plate of the post carrier within the etched portions of the photosensitive encapsulant; and

connecting an interconnect structure to the conductive posts.

16. The method of claim 15 , including removing the base plate of the post carrier.

17. The method of claim 15 , including forming a first build-up layer over a first side of the photosensitive encapsulant, the first build-up layer being electrically connected to the conductive posts.

18. The method of claim 17 , including depositing a second encapsulant over the semiconductor die.

19. The method of claim 18 , including planarizing the second encapsulant using chemical etching, or mechanical grinding.

20. The method of claim 15 , wherein the photosensitive encapsulant includes benzocyclobutene (BCB), polyimide (PI) or polymethylmethacrylate (PMMA).

21. The method of claim 15 , wherein the post carrier is prefabricated.

22. A method of making a semiconductor package, comprising:

providing a post carrier including a base plate and a conductive post;

disposing a photosensitive encapsulant over the base plate of the post carrier and around the conductive post;

etching the photosensitive encapsulant to expose a portion of the base plate of the post carrier; and

mounting a semiconductor die to the base plate of the post carrier within the etched portions of the photosensitive encapsulant.

23. The method of claim 22 , including forming a first build-up layer over a first side of the photosensitive encapsulant, the first build-up layer being electrically connected to the conductive posts.

24. The method of claim 22 , including depositing a second encapsulant over the semiconductor die.

25. The method of claim 24 , including planarizing the second encapsulant using chemical etching, or mechanical grinding to expose a top surface of the conductive post and the semiconductor die.