Wafer processing method

Patent metadata

Field	Value
Publication number	US-11088008-B2
Application number	US-201916438766-A
Country	US
Kind code	B2
Filing date	Jun 12, 2019
Priority date	Jun 19, 2018
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A wafer processing method includes a wafer providing step of providing the wafer by placing either of a polyolefin sheet or a polyester sheet each of which has a size equal to or larger than that of the wafer, on a flat upper surface of a support table and positioning a front surface of the wafer on an upper surface of the sheet, a sheet thermocompression bonding step of evacuating an enclosing environment in which the wafer is provided through the sheet on the support table, heating the sheet, pressing the wafer to pressure-bond the wafer to the sheet, thereby forming a raised portion by which an outer circumference of the wafer is surrounded, a back surface processing step of processing the back surface of the wafer, and a peeling step of peeling off the wafer from the sheet.

First claim

What is claimed is:

1. A wafer processing method of processing a back surface of a wafer having a plurality of devices formed on a front surface of the wafer, the plurality of devices being individually partitioned by a plurality of crossing division lines formed on the front surface of the wafer, the method comprising:
a wafer providing step of providing the wafer by placing either of a polyolefin sheet or a polyester sheet each of which has a size equal to or larger than that of the wafer, on a flat upper surface of a support table and positioning the front surface of the wafer on an upper surface of the sheet;
a sheet thermocompression bonding step of evacuating an enclosing environment in which the wafer is provided through the sheet on the support table, heating the sheet, pressing the wafer to pressure-bond the wafer to the sheet, thereby forming a raised portion by which an outer circumference of the wafer is surrounded, after carrying out the wafer providing step;
a back surface processing step of processing the back surface of the wafer after carrying out the sheet thermocompression bonding step; and
a peeling step of peeling off the wafer from the sheet, after carrying out the back surface processing step.

2. The wafer processing method according to claim 1 , wherein:
the support table includes heating means, and
the support table is heated by the heating means in the sheet thermocompression bonding step.

3. The wafer processing method according to claim 1 , wherein:
the upper surface of the support table is coated with a fluorine resin.

4. The wafer processing method according to claim 1 , wherein: grinding is performed on the back surface of the wafer in the back surface processing step.

5. The wafer processing method according to claim 1 , wherein:
the polyolefin sheet is selected from the group consisting of a polyethylene sheet, a polypropylene sheet, and a polystyrene sheet.

6. The wafer processing method according to claim 5 , wherein:
in a case in which the polyolefin sheet is selected, the polyolefin sheet includes the polyethylene sheet, and
the polyolefin sheet is heated to a temperature in the range of 120° C. to 140° C. in the sheet thermocompression bonding step.

7. The wafer processing method according to claim 5 , wherein:
in a case in which the polyolefin sheet is selected, the polyolefin sheet includes the polypropylene sheet, and
the polyolefin sheet is heated to a temperature in the range of 160° C. to 180° C. in the sheet thermocompression bonding step.

8. The wafer processing method according to claim 5 , wherein:
in a case in which the polyolefin sheet is selected, the polyolefin sheet includes the polystyrene sheet, and
the polyolefin sheet is heated to a temperature in the range of 220° C. to 240° C. in the sheet thermocompression bonding step.

9. The wafer processing method according to claim 1 , wherein:
the polyester sheet is selected from the group consisting of a polyethylene terephthalate sheet and a polyethylene naphthalate sheet.

10. The wafer processing method according to claim 7 , wherein:
in a case in which the polyester sheet is selected, the polyester sheet includes the polyethylene terephthalate sheet, and
the polyester sheet is heated to a temperature in the range of 250° C. to 270° C. in the sheet thermocompression bonding step.

11. The wafer processing method according to claim 7 , wherein:
in a case in which the polyester sheet is selected, the polyester sheet includes the polyethylene naphthalate sheet, and
the polyester sheet is heated to a temperature in the range of 160° C. to 180° C. in the sheet thermocompression bonding step.

Assignees

• Disco Corp

Inventors

• Kiuchi Hayato
• Yamamoto Keisuke
• Kimura Taichiro

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

• H10P54/00 Primary

  Cutting or separating of wafers, substrates or parts of devices · CPC title

• H10P52/00

  Grinding, lapping or polishing of wafers, substrates or parts of devices · CPC title

• H10P72/7402 Primary

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