Method of dividing wafer

Patent metadata

Field	Value
Publication number	US-10784164-B2
Application number	US-201615064209-A
Country	US
Kind code	B2
Filing date	Mar 8, 2016
Priority date	Mar 16, 2015
Publication date	Sep 22, 2020
Grant date	Sep 22, 2020

Abstract

A wafer having a device area on one side with a plurality of devices partitioned by division lines is divided into dies. An adhesive tape for protecting devices is attached to the one side of the wafer, the adhesive tape adhering to at least some, optionally all, of the devices. A carrier for supporting the tape is attached to the side of the tape opposite to the one side by an attachment means provided over an entire surface area of the adhesive tape which is in contact with the carrier. The wafer is cut along the division lines. The side of the wafer opposite to the one side is mechanically partially cut, and a remaining part of the cuts in the wafer is mechanically cut and/or cut by laser and/or cut by plasma from the side of the wafer opposite to the one side.

First claim

The invention claimed is:

1. A method of dividing a wafer, having on one side a device area with a plurality of devices partitioned by a plurality of division lines, into dies, the method comprising:
attaching an adhesive tape for protecting devices on the wafer to the one side of the wafer, the adhesive tape having an adhesive in direct contact with the devices and the adhesive is curable by an external stimulus that hardens the adhesive and lowers the adhesive force of the adhesive;
attaching a carrier for supporting the adhesive tape to the side of the adhesive tape being opposite to the side in contact with the devices by an attachment means, wherein the attachment means is an adhesive layer provided over an entire surface area of the adhesive tape which is in contact with the carrier, the adhesive layer forming the attachment means being curable by a external stimulus that lowers the adhesive force of the adhesive layer; and
cutting the wafer along the division lines; wherein:
the side of the wafer being opposite to the one side is mechanically partially cut, thereby forming a partial cut or partial cuts extending from the side being opposite to the one side to an area separated from the devices, to thereby define a remaining part, wherein said partial cut or each of said partial cuts extends to reach at least 50% of the thickness of the wafer; and
the remaining part of the wafer, in the thickness direction thereof in the region or regions where the partial cut or cuts had been formed, is mechanically cut and/or cut by laser and/or cut by plasma from the side of the wafer being opposite to the one side.

2. The method according to claim 1 , further comprising grinding the side of the wafer being opposite to the one side for adjusting the wafer thickness.

3. The method according to claim 2 , wherein the grinding of the wafer is performed before cutting of the wafer.

4. The method according to claim 2 , wherein the cutting of the wafer is performed before grinding of the wafer.

5. The method according to claim 1 , wherein a low-k layer is provided on the one side of the wafer and the low-k layer is mechanically cut and/or cut by laser and/or cut by plasma from the side of the wafer being opposite to the one side.

6. The method according to claim 1 , wherein the external stimulus includes heat, UV radiation, an electric field and/or a chemical agent.

7. The method according to claim 6 , further comprising applying the external stimulus to the adhesive of the adhesive tape in contact with the devices so as to lower the adhesive force of the adhesive.

8. The method according to claim 1 , further comprising attaching an adhesive pick up tape to the side of the wafer being opposite to the one side after cutting the wafer.

9. The method according to claim 1 , further comprising parallelizing the surface of the adhesive tape opposite the surface contacting the devices with the surface of the wafer opposite the one side.

10. The method according to claim 1 , wherein the carrier is made of a rigid material, such as silicon and/or glass and/or SUS.

11. The method according to claim 1 , wherein the partial cut or partial cuts is/are formed using a blade or a saw.

12. The method according to claim 11 , wherein the remaining part is cut by laser.

13. The method according to claim 11 , wherein the remaining part is cut by plasma.

14. The method according to claim 11 , wherein the remaining part is cut by a blade that has a width that is smaller than the width of the blade or saw used for forming the partial cut or cuts.

15. The method according to claim 1 , wherein a width of the partial cut or cuts is/are wider than that of the cut formed in the remaining part.

16. The method according to claim 1 , wherein said partial cut or each of said partial cuts extends to reach at least 70% of the thickness of the wafer.

17. The method according to claim 1 , wherein said partial cut or each of said partial cuts extends to reach at least 80% of the thickness of the wafer.

18. The method according to claim 1 , wherein said partial cut or each of said partial cuts extends to reach at least 90% of the thickness of the wafer.

Assignees

• Disco Corp

Inventors

• Priewasser Karl Heinz

Classifications

• H10P72/7422

  used to protect an active side of a device or wafer · CPC title

• H10P72/7416

  used during dicing or grinding · CPC title

• H10P72/744

  Details of chemical or physical process used for separating the auxiliary support from a device or a wafer · CPC title

• H10P72/7402

  Wafer tapes, e.g. grinding or dicing support tapes · CPC title

• H10P72/74

  using temporarily an auxiliary support · CPC title