U.S. patent application number 15/342241 was filed with the patent office on 2018-03-29 for wafer dicing method.
The applicant listed for this patent is CHIPBOND TECHNOLOGY CORPORATION. Invention is credited to Chih-Lung Chen, Wen-Hsiang Liao, Yung-Chi Liu, Chia-Jung Tu, Chung-Hsiang Wei.
Application Number | 20180090379 15/342241 |
Document ID | / |
Family ID | 61629247 |
Filed Date | 2018-03-29 |
United States Patent
Application |
20180090379 |
Kind Code |
A1 |
Tu; Chia-Jung ; et
al. |
March 29, 2018 |
WAFER DICING METHOD
Abstract
A wafer dicing method comprises providing a wafer and performing
a cutting procedure and a contacting procedure. The wafer includes
a plurality of dies and a metal layer, wherein the metal layer is
formed on a scribe line which is formed between adjacent dies. A
cutter is used to cut the metal layer along the scribe line during
the cutting procedure to form a plurality of dies on the wafer, and
the metal layer cut by the cutter remains a plurality of metal
burrs on the dies. A brush is used to contact with the metal burrs
along the cutting slot during the contracting procedure to prevent
each of the metal burrs from protruding from a surface of each of
the dies.
Inventors: |
Tu; Chia-Jung; (Hsinchu
City, TW) ; Chen; Chih-Lung; (Taipei City, TW)
; Liao; Wen-Hsiang; (Taichung City, TW) ; Wei;
Chung-Hsiang; (Hsinchu County, TW) ; Liu;
Yung-Chi; (New Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CHIPBOND TECHNOLOGY CORPORATION |
Hsinchu |
|
TW |
|
|
Family ID: |
61629247 |
Appl. No.: |
15/342241 |
Filed: |
November 3, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 2224/01 20130101;
H01L 21/6835 20130101; H01L 2221/68327 20130101; H01L 21/78
20130101 |
International
Class: |
H01L 21/78 20060101
H01L021/78; H01L 23/544 20060101 H01L023/544; H01L 21/304 20060101
H01L021/304 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 23, 2016 |
TW |
105130694 |
Claims
1. A wafer dicing method comprising: providing a wafer including a
plurality of dies and a metal layer, layer, wherein each of the
dies includes a surface and there is a scribe line formed between
adjacent dies, and wherein the metal layer is formed on the scribe
line; placing the wafer on a bearing surface of a carrier; and
performing a cutting procedure and a contacting procedure
simultaneously, wherein a cutter is used to cut the metal layer
along the scribe line during the cutting procedure to form a
plurality of cutting slots on the wafer such that a plurality of
metal burrs remain on the cutting slots of the dies, and using a
contacting portion of a brush to contact with each of the metal
burrs along the cutting slot during the contacting procedure to
prevent each of the metal burrs from protruding from the surface of
each of the dies wherein, during the simultaneous cutting and
contacting procedures, the contacting portion of the brush is
arranged behind the cutter along a cutting direction of the cutter
and the cutter and the contacting portion are located on the same
scribe line and wherein, before performing the simultaneous cutting
and contacting procedures, a first height exists between a terminal
of the cutter and the bearing surface of the carrier and a second
height exists between a contacting portion of the brush and the
bearing surface of the carrier and wherein the first height is
equal to or higher than the second height.
2. The wafer dicing method in accordance with claim 1, wherein each
of the metal burrs is separated from the die or bent downwardly
toward the cutting slot when the contacting portion of the brush
contacts with each of the metal burrs.
3-8. (canceled)
9. The wafer dicing method in accordance with claim 1, wherein the
contacting portion of the brush is made of flexible material, and
deformation of the contacting portion occurs during the contacting
procedure.
Description
FIELD OF THE INVENTION
[0001] This invention generally relates to a wafer dicing method,
more particularly to a wafer dicing method able to prevent metal
burrs from protruding on die surface.
BACKGROUND OF THE INVENTION
[0002] With reference to FIG. 11, a wafer 400 is firstly fixed on a
carrier 600 by a tape 500 in conventional wafer dicing method, and
then using a cutter (not shown) to cut the wafer 400 to form a
plurality of chips 410. However, a plurality of metal burrs 411
will be formed protruded from the surface of the chip 410 during
cutting. With reference to FIG. 12, when the chip 410 interconnects
with a plurality of bumps 710 on a substrate 700 which is made of
flexible material, glass or other materials by flip-chip
technology, the metal burrs 411 protruded from the surface of the
chip 410 will contact with the substrate 700 to cause leakage or
short circuit of semiconductor structure, or affect electric signal
input or output.
SUMMARY
[0003] The primary object of the present invention is to use a
brush to contact with metal burrs formed result from cutting metal
layer to prevent the metal burrs from protruding on die
surface.
[0004] A wafer dicing method of the present invention comprises
providing a wafer including a plurality of dies and a metal layer,
wherein each of the dies includes a surface and there is a scribe
line formed between adjacent dies, and wherein the metal layer is
formed on the scribe line; and performing a cutting procedure and a
contacting procedure, wherein a cutter is used to cut the metal
layer along the scribe line during the cutting procedure to form a
plurality of cutting slots on the wafer, and the metal layer cut by
the cutter remains a plurality of metal burrs on the dies, and
wherein a contacting portion of a brush is used to contact with
each of the metal burrs along the cutting slot during the
contacting procedure to prevent each of the metal burrs from
protruding from the surface of each of the dies.
[0005] The present invention uses the brush to contact with the
metal burrs during the contacting procedure for preventing the
metal burrs formed during the cutting procedure from protruding on
the surface of the die. The purpose of preventing the metal burrs
from protruding on the die surface is to prevent the metal burrs
from contacting with other components during follow-up package
process to cause leakage/short circuit or affect electric signal
transmission, and also prevent the metal burrs from damaging other
components during follow-up package process.
DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a flow chart illustrating a wafer dicing method in
accordance with a first embodiment of the present invention.
[0007] FIG. 2 is a perspective diagram illustrating a wafer and a
wafer dicing device in accordance with the first embodiment of the
present invention.
[0008] FIG. 3 is a lateral view diagram illustrating the wafer and
the wafer dicing device in accordance with the first embodiment of
the present invention.
[0009] FIG. 4 is a lateral view diagram illustrating the wafer and
the wafer dicing device in accordance with the first embodiment of
the present invention.
[0010] FIG. 5 is a lateral view diagram illustrating the wafer and
the wafer dicing device in accordance with the first embodiment of
the present invention.
[0011] FIG. 6 is a cross-sectional view diagram along A-A line in
FIG. 5.
[0012] FIG. 7 is a cross-sectional view diagram along B-B line in
FIG. 5.
[0013] FIG. 8 is a cross-sectional view diagram along C-C line in
FIG. 5.
[0014] FIG. 9 is a lateral view diagram illustrating a wafer and a
wafer dicing device in accordance with a second embodiment of the
present invention.
[0015] FIG. 10 is a lateral view diagram illustrating the wafer and
the wafer dicing device in accordance with the second embodiment of
the present invention.
[0016] FIG. 11 is a diagram illustrating a wafer after cutting.
[0017] FIG. 12 is a diagram illustrating a chip after flip-chip
interconnection.
DETAILED DESCRIPTION OF THE INVENTION
[0018] With reference to FIG. 1, a wafer dicing method 10 in
accordance with a first embodiment of the present invention
includes step 11 of providing wafer and step 12 of performing
cutting procedure and contacting procedure.
[0019] With reference to FIGS. 1, 2 and 3, a wafer 100 is provided
in step 11, preferably, the wafer 100 is made of silicon (Si) or
group III-V compound semiconductor materials (e.g. GaAs). The wafer
100 includes a plurality of dies 110 arranged in array and a metal
layer 120, wherein each of the dies 110 includes a surface 111
which can be the active or inactive surface of the die 110. There
is a scribe line 130 formed between adjacent dies 110, and the
metal layer 120 is formed on the scribe line 130, wherein the metal
layer 120 can electrically connect to the dies 110 for electric
test, or the metal layer 120 can be used for cutter aligning in
cutting procedure.
[0020] With reference to FIGS. 2 and 3, the wafer 100 is cut by a
wafer dicing device 200 in the present invention, wherein the wafer
dicing device 200 includes a carrier 210, a cutter 210 and a brush
230. The cutter 220 and the brush 230 are located above the carrier
210 and faced toward the surface 111 of each of the dies 110. The
wafer 100 is placed on a bearing surface 211 of the carrier 210,
and the carrier 210 is used to carry the wafer 100 for movement
relative to the cutter 220 and the brush 230 in this embodiment,
wherein the movement includes horizontal and vertical movement. In
other embodiment, the cutter 220 and the brush 230 can be moved
relative to the wafer 100, wherein the movement also includes
horizontal and vertical movement. Preferably, the cutter 220 is a
cutting wheel, and a contacting portion 231 of the brush 230 is
made of flexible material so that the wafer 100 will not be
damaged. The contacting portion 231 of the brush 230 can be
selected from artificial filament, animal filament or plant
filament. In this embodiment, the contacting portion 231 of the
brush 230 is DuPont 612 nylon filament.
[0021] With reference to FIGS. 2 and 3, there is a fixing tape 300
between the wafer 100 and the carrier 210, wherein the fixing tape
300 is used to fix the wafer 100 for preventing the wafer 100 from
moving during cutting.
[0022] With reference to FIG. 3, the cutter 220 includes a terminal
221, and the contacting portion 231 of the brush 230 includes a
contacting end 231a, wherein the terminal 221 of the cutter 220 and
the contacting end 231a of the contacting portion 231 both face
toward the bearing surface 211 of the carrier 210. A first height
H1 is defined between the terminal 221 of the cutter 220 and the
bearing surface 211, and a second height H2 is defined between the
contacting end 231a of the contacting portion 231 and the bearing
surface 211, wherein the first height H1 is equal to or higher than
the second height H2 before step 12 of performing cutting procedure
and contacting procedure so that the contacting portion 231 of the
brush 230 cannot contact with the wafer 100 is preventable when the
carrier 210 is moved upwardly to make the cutter 220 contacting
with the wafer 100. In this embodiment, the first height H1 is
higher than the second height H2.
[0023] With reference to FIGS. 1, 4 and 5, a cutting procedure and
a contacting procedure are performed in step 12. The cutter 220 is
used to cut the metal layer 120 along the scribe line 130 to form a
plurality of cutting slots 140 on the wafer 110, wherein the dies
110 located at both sides of the cutting slot 140 are electrically
disconnected with each other. With reference to FIG. 5, the wafer
100 is moved upwardly by the carrier 210 to contact with the cutter
220 in this embodiment, and then the wafer 100 is horizontally
moved relative to the cutter 220 by the carrier 210 to cut the
metal layer 120 along the scribe line 130 for forming the cutting
slot 140. In this embodiment, the contacting portion 231 of the
brush 230 following the cutter 220 contacts with the surface 111 of
the die 110 and at least one cutting slot 140 when the cutter 220
cuts the metal layer 120 along the scribe line 130.
[0024] With reference to FIGS. 5 and 6, FIG. 6 is a cross-sectional
view diagram along A-A line in FIG. 5. The metal layer 120 will
remain a plurality of metal burrs 121 on the dies 110 when the
cutter 220 cuts the metal layer 120 along the scribe line 130, and
the metal burrs 121 will protrude from the surface 111 of each of
the dies 110 because of cutting stress.
[0025] With reference to FIGS. 5 and 7, FIG. 7 is a cross-sectional
view diagram along B-B line in FIG. 5. In the contacting procedure,
the contacting portion 231 of the brush 230 can touch the surface
111 of each of the dies 110 and the cutting slot 140 along the
cutting slot 140, and contact with each of the metal burrs 121,
wherein deformation of the contacting portion 231 will occur during
the contacting procedure because the contacting portion 231 is made
of flexible material.
[0026] With reference to FIGS. 5 and 8, FIG. 8 is a cross-sectional
view diagram along C-C line in FIG. 5. The contacting procedure can
prevent the metal burrs 121 from protruding on the surface 111 of
each of the dies 110. Preferably, each of the metal burrs 121 will
be divided from the dies 110 or bent downwardly toward the cutting
slot 140 by horizontal push force or vertical press force from the
contacting portion 231 of the brush 230, so the problem that the
metal burrs 121 protrude from the surface 111 of each of the dies
110 can be effectively solved. Therefore, the contacting procedure
can prevent the metal burrs 121 from electrically connecting with
other elements in the follow-up package processes to cause leakage
or short circuit, and can prevent the metal burrs 121 from
affecting electric signal input or output, or damaging other
elements to affect semiconductor efficacy.
[0027] The cutting procedure and the contacting procedure are
performed simultaneously in this embodiment, so the wafer 100 can
be cleaned by air or water curtain to remove wafer fragment formed
during the cutting procedure and the metal burrs 121 divided during
the contacting procedure for preventing the wafer fragment or the
metal burrs 121 from remaining on the wafer 100.
[0028] With reference to FIG. 5, in this embodiment, the contacting
portion 231 of the brush 230 is placed behind the cutter 220 along
with the cutting direction of the cutter 220, and the cutter 220
and the contacting portion 231 of the brush 230 are located on the
same scribe line 130. Owing to the cutting procedure and the
contacting procedure are performed simultaneously, the contacting
portion 231 of the brush 230 can immediately contact with the metal
burrs 121 along the cutting slot 140 formed newly to divide the
metal burrs 121 from the dies 110 or bend the metal burrs 121
downwardly toward the cutting slot 140 when the cutter 220 cuts the
metal layer 120 along the scribe line 130 to form the cutting slot
140, to prevent the metal burrs 121 from protruding from the
surface 111 of the die 110.
[0029] In other embodiment, the contacting procedure can be
performed after completing the cutting procedure. That means the
contacting portion 231 of the brush 230 contacts with the metal
burrs 121 along each of the cutting slots 140 to divide the metal
burrs 121 from the die 110 or bend the metal burrs 121 downwardly
toward the cutting slot 140 after the cutter 220 cuts the wafer 100
to make all the dies 110 electrically disconnecting with each
other.
[0030] Second embodiment of the present invention is illustrated in
FIGS. 9 and 10, the difference between the second embodiment and
the first embodiment is the contacting portion 231 of the brush 230
is placed on the side of the cutter 220 along with the cutting
direction of the cutter 220, and the cutter 220 and the contacting
portion 231 of the brush 230 are located on the different scribe
lines 130. Owing to the cutting procedure and the contacting
procedure are performed simultaneously, the brush 230 located on
the side of the cutter 220 can contact with the metal burrs 121
along the cutting slot 140 formed previously to divide the metal
burrs 121 from the die 110 or bend the metal burrs 121 downwardly
toward the cutting slot 140 when the cutter 220 cuts the wafer 100
to form new cutting slot 140. With reference to FIG. 10, the
contacting portion 231 of the brush 230 is separated from the
cutter 220 by at least one scribe line 130 preferably to prevent
interference between the contacting portion 231 of the brush 230
and the cutter 220.
[0031] While this invention has been particularly illustrated and
described in detail with respect to the preferred embodiments
thereof, it will be clearly understood by those skilled in the art
that is not limited to the specific features shown and described
and various modified and changed in form and details may be made
without departing from the spirit and scope of this invention.
* * * * *