Method of forming protective material between semiconductor die stacked on semiconductor wafer to reduce defects during singulation

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

providing a semiconductor wafer containing a plurality of first semiconductor die;

mounting a plurality of second semiconductor die to a first surface of the semiconductor wafer;

placing a tape on a second surface of the semiconductor wafer opposite the first surface of the semiconductor wafer;

forming a protective material over the second semiconductor die and first surface of the semiconductor wafer;

singulating the semiconductor wafer between the second semiconductor die into individual die-to-wafer packages each containing the second semiconductor die stacked on the first semiconductor die, the protective material protecting the semiconductor wafer during singulation;

removing the tape;

mounting the die-to-wafer package to a substrate;

removing the protective material to expose the second semiconductor die and first surface of the semiconductor wafer; and

depositing an encapsulant over the die-to-wafer package and substrate.

2. The method of claim 1 , further including forming a plurality of conductive vias through the semiconductor wafer.

3. The method of claim 1 , wherein the protective material includes polyvinyl alcohol and water.

4. The method of claim 1 , further including depositing underfill material beneath the first semiconductor die.

5. The method of claim 1 , further including depositing underfill material beneath the second semiconductor die.

6. The method of claim 1 , wherein the substrate includes a build-up interconnect structure.

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

providing a semiconductor wafer containing a plurality of first semiconductor die;

mounting a plurality of second semiconductor die to a surface of the semiconductor wafer;

forming a protective material over the second semiconductor die and surface of the semiconductor wafer;

singulating the semiconductor wafer between the second semiconductor die into individual die-to-wafer packages each containing the second semiconductor die stacked on the first semiconductor die, the protective material protecting the semiconductor wafer during singulation; and

removing the protective material to expose the second semiconductor die and surface of the semiconductor wafer.

8. The method of claim 7 , wherein the protective material includes polyvinyl alcohol and water.

9. The method of claim 7 , wherein the protective material includes encapsulant.

10. The method of claim 7 , further including:

forming a build-up interconnect structure over the first semiconductor die; and

depositing an encapsulant over the first semiconductor die, second semiconductor die, and build-up interconnect structure.

11. The method of claim 7 , further including mounting the die-to-wafer package to a substrate.

12. The method of claim 7 , further including forming a plurality of conductive vias through the semiconductor wafer.

13. The method of claim 7 , further including:

depositing first underfill material beneath the first semiconductor die; and

depositing second underfill material beneath the second semiconductor die.

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

providing a semiconductor wafer;

forming a plurality of channels in a first surface of the semiconductor wafer;

depositing a protective layer over and between the channels in the first surface of the semiconductor wafer;

grinding a second surface of the semiconductor wafer opposite the first surface of the semiconductor wafer to reduce a thickness of the semiconductor wafer, the protective layer protecting the channels during grinding; and

removing the protective layer to expose the channels in the first surface of the semiconductor wafer.

15. The method of claim 14 , further including removing the protective layer with deionized water.

16. The method of claim 14 , further including singulating the semiconductor wafer.

17. The method of claim 14 , wherein the protective layer includes polyvinyl alcohol and water.

18. The method of claim 14 , further including forming a plurality of conductive vias through the semiconductor wafer.

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

providing a semiconductor wafer having a plurality of semiconductor die;

forming a plurality of channels in a first surface of the semiconductor wafer between the semiconductor die;

depositing a protective material over the first surface of the semiconductor wafer and the channels;

grinding a second surface of the semiconductor wafer to remove a portion of the semiconductor wafer; and

removing the protective material to expose the first surface of the semiconductor wafer and the channels.

20. The method of claim 19 , wherein grinding the second surface of the semiconductor wafer further includes singulating the semiconductor wafer between the semiconductor die.

21. The method of claim 19 , wherein forming the plurality of channels in the first surface of the semiconductor wafer includes forming the channels at a depth of 30-50 percent of a reduced thickness of the semiconductor wafer.

22. The method of claim 19 , wherein the protective material is a water-soluble material.

23. The method of claim 19 , wherein the protective material includes polyvinyl alcohol and water.

24. The method of claim 19 , further including forming a plurality of conductive vias through the semiconductor wafer.

25. The method of claim 7 , wherein removing the protective material exposes the surface of the semiconductor wafer.