Grinding method for circular plate-shaped workpiece

Patent metadata

Field	Value
Publication number	US-2023234179-A1
Application number	US-202318152262-A
Country	US
Kind code	A1
Filing date	Jan 10, 2023
Priority date	Jan 27, 2022
Publication date	Jul 27, 2023
Grant date	—

Abstract

There is provided a grinding method that is applied when a workpiece having a first surface and a second surface is to be ground from the second surface. The grinding method includes a first grinding step of causing first grindstones to come into contact with the workpiece to grind the workpiece and thereby form on the workpiece a circular plate-shaped first thin plate portion and an annular first thick plate portion surrounding the first thin plate portion, and a second grinding step of causing second grindstones to come into contact with the first thick plate portion and the first thin plate portion to grind the workpiece and thereby form on the workpiece a thin circular plate-shaped second thin plate portion that has a larger diameter than the first thin plate portion and an annular second thick plate portion surrounding the second thin plate portion.

First claim

What is claimed is:

1 . A grinding method applied when a circular plate-shaped workpiece having a first surface and a second surface on an opposite side of the first surface is to be ground from the second surface, the grinding method comprising:
a first grinding step of moving the workpiece and a first grinding wheel in which a plurality of first grindstones each including abrasive grains are arrayed in an annular area with a first dimeter smaller than a diameter of the workpiece relative to each other in a first direction that intersects with the second surface, while mutually rotating the workpiece and the first grinding wheel, and causing the first grindstones to come into contact with the workpiece from the second surface side, to grind the workpiece and thereby form on the workpiece a circular plate-shaped first thin plate portion and an annular first thick plate portion surrounding the first thin plate portion; and a second grinding step of, after the first grinding step, moving the workpiece and a second grinding wheel in which a plurality of second grindstones each including abrasive grains smaller than those included in the first grindstones are arrayed in an annular area with a second dimeter smaller than the diameter of the workpiece relative to each other in a second direction that intersects with the second surface, while mutually rotating the workpiece and the second grinding wheel, and causing the second grindstones to come into contact with the first thick plate portion and the first thin plate portion from the second surface side, to grind the workpiece and thereby form on the workpiece a thin circular plate-shaped second thin plate portion that has a larger diameter than the first thin plate portion and an annular second thick plate portion surrounding the second thin plate portion, wherein, in the second grinding step, the second grindstones are caused to come into contact with an area on the second surface that remains on the first thick plate portion at a distance of equal to or more than a width of the second grindstones in a direction of the second diameter from an inner edge of the second surface toward an outer side.

2 . The grinding method according to claim 1 , wherein,
in the first grinding step, while the first grinding wheel and the workpiece are moved relative to each other in a direction perpendicular to the second surface, a center of rotation of the first grinding wheel and a center of rotation of the workpiece are caused to come close to each other in a direction parallel to the second surface.

3 . The grinding method according to claim 1 , wherein,
in the second grinding step, while the second grinding wheel and the workpiece are moved relative to each other in a direction perpendicular to the second surface, a center of rotation of the second grinding wheel and a center of rotation of the workpiece are caused to come close to each other in a direction parallel to the second surface.

4 . The grinding method according to claim 2 , wherein,
in the second grinding step, while the second grinding wheel and the workpiece are moved relative to each other in the direction perpendicular to the second surface, a center of rotation of the second grinding wheel and a center of rotation of the workpiece are caused to come close to each other in the direction parallel to the second surface.

Assignees

• Disco Corp

Inventors

• Suzuki Yoshikazu
• Tanemura Daisuke

Classifications

• H10P52/00

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

• H10P72/0428

  Apparatus for mechanical treatment or grinding or cutting · CPC title

• B24B7/228 Primary

  for grinding thin, brittle parts, e.g. semiconductors, wafers (grinding edges of thin, brittle parts B24B9/065) · CPC title

• B24D7/06

  with inserted abrasive blocks, e.g. segmental · CPC title

• B24B1/00

  Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes · CPC title