Ultra thin bumped wafer with under-film
View Patent ↗A semiconductor device begins with a wafer having a plurality of bumps formed on a surface of the wafer. An under-film layer is formed over the wafer to completely cover all portions of the bumps with the under-film layer. An adhesive layer is formed over the under-film layer. A support layer is attached over the adhesive layer. A back surface of the wafer undergoes grinding. The support layer provides structural support to the wafer. The support layer is removed to expose the adhesive layer. The adhesive layer is removed to expose the under-film layer. The wafer is singulated into semiconductor die. The semiconductor die is mounted to a substrate by applying force to a back surface of the semiconductor die to press the bumps through under-film layer to contact the substrate while the under-film layer provides an underfill between the semiconductor die and substrate.
1. A method of forming a semiconductor device, comprising:
providing a wafer having a plurality of bumps formed on a surface of the wafer;
forming an under-film layer over the bumps formed on the surface of the wafer to completely cover all portions of the bumps with the under-film layer;
forming an adhesive layer over the under-film layer after forming the under-film layer over the bumps on the surface of the wafer;
attaching a support layer containing glass or acryl board over the adhesive layer after forming the adhesive layer over the under-film layer;
grinding a back surface of the wafer, wherein the support layer provides structural support to the wafer during the grinding process;
laminating a dicing saw tape to the back surface of the wafer following the grinding process;
removing the support layer to expose the adhesive layer which remains disposed over the under-film layer;
removing the adhesive layer after removing the support layer to expose the under-film layer while all portions of the bumps remain completely covered by the under-film layer after removing the adhesive layer;
singulating the wafer into a plurality of semiconductor die; and
mounting the semiconductor die to a substrate by applying force to a back surface of the semiconductor die to press the bumps through under-film layer to contact the substrate while the under-film layer provides an underfill between the semiconductor die and substrate.
2. The method of claim 1 , further including removing the dicing saw tape to singulate each of the plurality of semiconductor die.
3. The method of claim 1 , wherein grinding the back surface of the wafer removes between zero (0) and two (2) mils of material from the back surface of the wafer.
4. The method of claim 1 , wherein the adhesive layer is comprised of an ultraviolet (UV) tape, thermoplastic resin, or photo-resist material.
5. A method of making a semiconductor device, comprising:
providing a wafer having a plurality of bumps formed on a surface of the wafer;
forming an under-film layer over the bumps formed on the surface of the wafer to completely cover all portions of the bumps with the under-film layer;
forming an adhesive layer over the under-film layer after forming the under-film layer over the bumps on the surface of the wafer;
attaching a support layer containing glass, acryl board, or wafer material over the adhesive layer after forming the adhesive layer over the under-film layer;
removing a portion of a back surface of the wafer;
removing the support layer to expose the adhesive layer which remains disposed over the under-film layer;
removing the adhesive layer after removing the support layer to expose the under-film layer while all portions of the bumps remain completely covered by the under-film layer after removing the adhesive layer;
singulating the wafer into a plurality of semiconductor die; and
mounting the semiconductor die to a substrate by applying force to a back surface of the semiconductor die to press the bumps through under-film layer to contact the substrate while the under-film layer provides an underfill between the semiconductor die and substrate.
6. The method of claim 5 , further including applying dicing tape to the back surface of the wafer after removing the portion of the back surface of the wafer.
7. The method of claim 5 , further including removing up to two mils of the back surface of the wafer.
8. The method of claim 5 , wherein the adhesive layer includes ultraviolet tape, thermoplastic resin, or photo-resist material.
9. The method of claim 5 , wherein the under-film layer includes an epoxy or acryl adhesive material.
10. The method of claim 5 , further including forming the under-film layer by spin coating or screen printing.
11. A method of making a semiconductor device, comprising:
providing a wafer having a plurality of bumps formed on a surface of the wafer;
forming an under-film layer over the bumps formed on the surface of the wafer to completely cover all portions of the bumps with the under-film layer;
forming an adhesive layer over the under-film layer after forming the under-film layer over the bumps on the surface of the wafer;
attaching a support layer over the adhesive layer after forming the adhesive layer over the under-film layer;
removing a portion of a back surface of the wafer;
removing the support layer to expose the adhesive layer which remains disposed over the under-film layer;
removing the adhesive layer after removing the support layer to expose the under-film layer while all portions of the bumps remain completely covered by the under-film layer after removing the adhesive layer;
singulating the wafer into a plurality of semiconductor die; and
mounting the semiconductor die to a substrate by applying force to a back surface of the semiconductor die to press the bumps into contact with the substrate while the under-film layer provides an underfill between the semiconductor die and substrate.
12. The method of claim 11 , further including applying dicing tape to the back surface of the wafer after removing the portion of the back surface of the wafer.
13. The method of claim 11 , further including removing up to two mils of the back surface of the wafer.
14. The method of claim 11 , wherein the support layer includes glass, acryl board, or wafer material.
15. The method of claim 11 , wherein the adhesive layer includes ultraviolet tape, thermoplastic resin, or photo-resist material.
16. The method of claim 11 , wherein the under-film layer includes an epoxy or acryl adhesive material.
17. A method of making a semiconductor device, comprising:
providing a wafer having a plurality of bumps formed on a surface of the wafer;
forming an under-film layer over the bumps formed on the surface of the wafer;
forming an adhesive layer over the under-film layer after forming the under-film layer over the bumps on the surface of the wafer;
removing the adhesive layer to expose the under-film layer while all portions of the bumps remain completely covered by the under-film layer;
singulating the wafer into a plurality of semiconductor die; and
mounting the semiconductor die to a substrate by applying force to a back surface of the semiconductor die to press the bumps into contact with the substrate while the under-film layer provides an underfill between the semiconductor die and substrate.
18. The method of claim 17 , further including:
attaching a support layer over the adhesive layer after forming the adhesive layer over the under-film layer;
removing a portion of a back surface of the wafer; and
removing the support layer to expose the adhesive layer which remains disposed over the under-film layer.
19. The method of claim 18 , further including applying dicing tape to the back surface of the wafer after removing the portion of the back surface of the wafer.
20. The method of claim 17 , wherein the under-film layer completely covers all portions of the bumps.