Wafer dicing method

Patent metadata

Field	Value
Publication number	US-10658239-B2
Application number	US-201816106690-A
Country	US
Kind code	B2
Filing date	Aug 21, 2018
Priority date	Dec 12, 2017
Publication date	May 19, 2020
Grant date	May 19, 2020

Abstract

This disclosure provides wafer dicing methods, and relates to the field of semiconductor technologies. Implementations of the dicing method may include: performing laser stealth dicing processing on a wafer from a back surface of the wafer; performing grinding and thinning processing on the back surface of the wafer after performing the laser stealth dicing processing; sticking a dicing tape on the back surface of the wafer after performing the grinding and thinning processing; and performing separation processing on the wafer after sticking the dicing tape. In some implementations, stealth dicing (SD) is performed before grinding, so that a laser is directly imposed on a back surface of a wafer, thereby alleviating a laser attenuation problem and lowering requirements on light transmittance of a dicing tape.

First claim

What is claimed is:

1. A wafer dicing method, comprising:
performing grooving processing on a front surface of a wafer to form a dicing line;
sticking a protection tape on the front surface of the wafer after performing the grooving processing;
performing laser stealth dicing processing on the wafer from a back surface of the wafer after sticking the protection tape, wherein a dicing path of the laser stealth dicing is aligned with the dicing line;
performing grinding and thinning processing on the back surface of the wafer after performing the laser stealth dicing processing;
sticking a dicing tape on the back surface of the wafer after performing the grinding and thinning processing;
removing the protection tape after sticking the dicing tape; and
performing separation processing on the wafer after sticking the dicing tape after removing the protection tape;
wherein a metal layer is formed on the front surface of the wafer and in the step of performing grooving processing on the front surface of the wafer, the metal layer is etched to form the dicing line.

2. The method according to claim 1 , wherein the step of performing separation processing on the wafer comprises:
fixing the wafer on a support platform using the dicing tape; and
performing expansion processing on the dicing tape after fixing the wafer on the support platform, wherein in a process of performing the expansion processing on the dicing tape, the wafer is separated into multiple chips.

3. The method according to claim 2 , wherein:
in the process of performing the expansion processing on the dicing tape, heating processing is further performed on the dicing tape.

4. The method according to claim 1 , wherein:
after the grinding and thinning processing is performed on the back surface of the wafer, the thickness of the wafer after the wafer is thinned is less than or equal to 50 micrometers.

5. The method according to claim 1 , wherein:
the width of the dicing line is greater than the width of the dicing path of the laser stealth dicing.

6. The method according to claim 5 , wherein:
the width of the dicing line is less than or equal to 20 micrometers; and
the width of the dicing path is less than or equal to 2 micrometers.

7. The method according to claim 1 , wherein the wafer is a silicon chip.

Assignees

• Semiconductor Mfg Int Beijing Corp
• Semiconductor Mfg Int Shanghai Corp
• Semiconductor Mfg International Beijing Corp
• Semiconductor Mfg International Shanghai Corp

Inventors

• Lu Lihui
• Fei Chunchao
• Chiang Po Yuan
• Wang Yaping

Classifications

• B23K26/40

  taking account of the properties of the material involved · CPC title

• B23K26/0006

  taking account of the properties of the material involved (B23K26/32, B23K26/40 take precedence) · CPC title

• B23K26/0093

  combined with mechanical machining or metal-working covered by other subclasses than B23K · CPC title

• B23K26/57

  the laser beam entering a face of the workpiece from which it is transmitted through the workpiece material to work on a different workpiece face, e.g. for effecting removal, fusion splicing, modifying or reforming · CPC title

• B23K2103/50

  Inorganic materials other than metals or composite materials · CPC title