U.S. patent application number 14/319416 was filed with the patent office on 2014-10-23 for label sheet for cleaning and conveying member having cleaning function.
This patent application is currently assigned to NITTO DENKO CORPORATION. The applicant listed for this patent is NITTO DENKO CORPORATION. Invention is credited to Makoto NAMIKAWA, Jirou NUKAGA, Yoshio TERADA, Eiji TOYODA.
Application Number | 20140311525 14/319416 |
Document ID | / |
Family ID | 26613266 |
Filed Date | 2014-10-23 |
United States Patent
Application |
20140311525 |
Kind Code |
A1 |
NAMIKAWA; Makoto ; et
al. |
October 23, 2014 |
LABEL SHEET FOR CLEANING AND CONVEYING MEMBER HAVING CLEANING
FUNCTION
Abstract
A label sheet for cleaning is formed of a label for cleaning
including a cleaning layer having a 180.degree. peeling adhesion to
a silicon wafer of 0.20 N/10 mm or less after receiving an active
energy and an adhesive layer provided on one of surfaces of said
cleaning layer, and a separator on which the label is removably
provided through the adhesive layer.
Inventors: |
NAMIKAWA; Makoto; (Osaka,
JP) ; TERADA; Yoshio; (Osaka, JP) ; NUKAGA;
Jirou; (Osaka, JP) ; TOYODA; Eiji; (Osaka,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NITTO DENKO CORPORATION |
Osaka |
|
JP |
|
|
Assignee: |
NITTO DENKO CORPORATION
Osaka
JP
|
Family ID: |
26613266 |
Appl. No.: |
14/319416 |
Filed: |
June 30, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13117707 |
May 27, 2011 |
|
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|
14319416 |
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10297184 |
Dec 3, 2002 |
|
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PCT/JP01/03850 |
May 8, 2001 |
|
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13117707 |
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Current U.S.
Class: |
134/6 ;
15/104.002 |
Current CPC
Class: |
C11D 11/0047 20130101;
A47L 25/005 20130101; Y10T 428/1495 20150115; Y10T 428/1471
20150115; Y10T 428/14 20150115; B08B 7/0028 20130101; B08B 13/00
20130101; C11D 11/0058 20130101; Y10T 156/1075 20150115; Y10T
428/24752 20150115; H01L 21/67028 20130101 |
Class at
Publication: |
134/6 ;
15/104.002 |
International
Class: |
A47L 25/00 20060101
A47L025/00; B08B 7/00 20060101 B08B007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 9, 2001 |
JP |
2001-109405 |
Apr 10, 2001 |
JP |
2001-111791 |
Claims
1. A conveying member having a cleaning function, comprising a
conveying member and a cleaning sheet provided on the conveying
member, wherein the cleaning sheet comprises a cleaning layer
having a modulus of tensile elasticity of 10 MPa or more (in
accordance with JIS K7127) and a 180.degree. peeling adhesion to a
silicon wafer (mirror surface) of 0.20 N/10 mm or less, and wherein
the cleaning sheet has a smaller shape than that of the conveying
member and the cleaning sheet does not protrude from an end of the
conveying member.
2. The conveying member having a cleaning function according to
claim 1, wherein the cleaning sheet comprises the cleaning layer
provided on one surface of a base material and an ordinary adhesive
layer provided on the other surface of the base material.
3. The conveying member having a cleaning function according to
claim 2, wherein a surface of the cleaning layer is protected by a
removing film.
4. A. label sheet for cleaning comprising at least one label,
wherein the label comprises a cleaning layer provided on one
surface of a base material with a surface thereof protected by a
removing film and the other surface of the base material provided
removably on a separator through an ordinary adhesive layer,
wherein a shape of the label is smaller than that of the conveying
member, and wherein the label sheet for cleaning is provided as the
cleaning sheet in the conveying member having a cleaning function
according to claim 1.
5. The label sheet for cleaning according to claim 4, wherein a
plurality of labels for cleaning are continuously provided on an
elongated separator at intervals.
6. The conveying member having a cleaning function according to
claim 1, wherein the cleaning layer is a curing type adhesive which
is polymerized and cured upon receipt of an active energy.
7. The label sheet for cleaning according to claim 4, wherein the
cleaning layer is a curing type adhesive which is polymerized and
cured upon receipt of an active energy.
8. A method of cleaning a substrate processing equipment, which
comprises conveying the conveying member having a cleaning function
according to claim 1 into the substrate processing equipment.
Description
[0001] This is a continuation of application Ser. No. 13/117,707
filed May 27, 2011, which is a divisional of application Ser. No.
10/297,184 filed Dec. 3, 2002, which is a 371 Application of
PCT/JP01/03850 filed May 8, 2001, which claims priority from
Japanese Patent Application No. 2001-109405 filed Apr. 9, 2001 and
Japanese Patent Application No. 2001-111791 filed Apr. 10, 2001.
The entire disclosures of the prior applications are hereby
incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a label sheet for cleaning
equipment, and a label sheet for cleaning on a conveying member for
use in a clean substrate processing apparatus, for example,
manufacturing equipment or checking equipment for a semiconductor,
a flat panel display or a printed board.
BACKGROUND ART
[0003] Various forms of substrate processing equipment utilize a
conveying system to convey a substrate in physical contact with the
conveying system. In this case, if foreign matters stick to the
substrate or the conveying system, succeeding substrates are
successively contaminated. Therefore, it is necessary to
periodically stop the equipment to carry out a washing process. For
this reason, there is a problem in that an availability factor of
the equipment is reduced and a great deal of labor is required. In
order to solve the problem, there have been proposed: (1) a method
of removing foreign matter sticking on portions of a substrate
processing equipment by conveying a substrate having an adhesive
substance fastened thereto (for example, Unexamined Japanese Patent
Publication 10-154686); and (2) a method of removing foreign matter
sticking to the back face of a substrate by conveying a
plate-shaped member (Unexamined Japanese Patent Publication
11-87458).
[0004] Of these methods, the method of removing foreign matter by
conveying a plate-shaped member allows easy conveyance of the
plate-shaped member, but is relatively less effective in cleaning
foreign matter.
[0005] In contrast, the method of removing foreign matter by
conveying a substrate having an adhesive substance fastened thereto
is relatively more effective in cleaning foreign matter. However,
there is a possibility that the adhesive substance and a portion of
the equipment might be bonded too strongly to be removed.
Therefore, the substrate might not be conveyed reliably. In
particular, when a pressure reducing absorption mechanism is used
for a chuck table of the equipment, this problem is prevalent.
[0006] Further, when the adhesive substance (i.e., the cleaning
sheet) is fastened to the substrate, there has been known a method
of bonding a cleaning sheet that is larger in size than the
substrate to the substrate, and then cutting the cleaning sheet
along the shape of the substrate (i.e., a direct cutting method).
However, in such a method, refuse from the cut away portion might
be generated and might stick to the substrate or the equipment.
[0007] Alternatively, another method of bonding a cleaning sheet to
a substrate is known where the cleaning sheet is previously punched
to the shape of the substrate before being fastened to the
substrate (i.e., a precutting method). In this case, the generation
of refuse is reduced as compared to the direct cutting method. In
some cases, however, an adhesive of the cleaning sheet might leak
out of a punched surface during the sheet punching and might stick
to an end of the cleaning sheet or substrate so that an appearance
is deteriorated or conveyance troubles are caused. Furthermore, in
the case in which an adhesive of a polymerization and curing type
is used, the adhesive on the end of the cleaning sheet causes
defective curing by polymerization inhibition due to oxygen
inhibition if the curing is carried out after the sheet punching.
Therefore, the contact portion of the substrate processing
equipment might be contaminated by the adhesive.
SUMMARY OF THE INVENTION
[0008] In view of the above, it is an object of the invention to
provide a label sheet for cleaning which: can be reliably conveyed
on a substrate in substrate processing equipment; removes foreign
matter sticking in the equipment easily and reliably; enhances a
working efficiency; and generates no refuse because sheet cutting
is not required after bonding to the substrate.
[0009] It is another object of the invention to provide a method of
manufacturing a label sheet for cleaning which: can be reliably
conveyed on a substrate in substrate processing equipment; removes
foreign matters sticking into the equipment easily and reliably;
and results neither in defective punching during sheet punching nor
in defective adhesive curing in a precutting method.
[0010] In one aspect of the invention, when the cleaning sheet or
the substrate having the sheet fastened thereto is conveyed to
remove foreign matter sticking in substrate processing equipment,
setting an adhesion to a specific value or less using an active
energy source and setting the cleaning sheet to have the label
shape results in easy and reliable removal of the foreign matter
without the troubles described above.
[0011] In another aspect of the invention, a label for cleaning
including an ordinary adhesive layer on one surface having a
180.degree. peeling adhesion to a silicon wafer (mirror surface) of
0.20 N/10 mm or less, after receiving an active energy, is
removably provided on a separator through the ordinary adhesive
layer.
[0012] In another aspect of the invention, the label sheet also may
be constituted such that the cleaning layer is provided on a
surface of a base material, an ordinary adhesive layer is provided
on the other surface, and the label sheet is removably provided on
a separator through the ordinary adhesive layer.
[0013] In another aspect of the invention, a plurality of the
labels for cleaning may be continuously provided on an elongated
separator at regular intervals.
[0014] In another aspect of the invention, a label sheet for
cleaning is provided on a conveying member, where the label sheet
for cleaning has a smaller size than that of the conveying member.
Further, the label sheet may be shaped so as not to protrude from
an end of the conveying member.
[0015] In another aspect of the invention, a method of
manufacturing a label sheet for cleaning is provided in which a
cleaning layer formed of an adhesive is provided on one surface of
a base material with a surface thereof protected by a removable
film, and the other surface of the base material is removably
provided on a separator through an ordinary adhesive layer, wherein
the cleaning layer is a curing type adhesive which is polymerized
and cured upon receipt of an active energy and the step of punching
a sheet to have a shape of the label is carried out after a
polymerization and curing reaction of the adhesive of the cleaning
layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above and other objects, features and advantages of the
invention will be evident from the following detailed description
of exemplary embodiments thereof in conjunction with the attached
drawings, in which:
[0017] FIG. 1 is a partial plan view showing an exemplary
embodiment of a label sheet for cleaning according to the
invention;
[0018] FIG. 2 is a sectional view taken along a line II-II of FIG.
1;
[0019] FIG. 3 is a partial plan view showing another exemplary
embodiment of a label sheet for cleaning according to the
invention;
[0020] FIG. 4 is a partial plan view showing yet another exemplary
embodiment of a label sheet for cleaning according to the
invention;
[0021] FIG. 5 is a partial plan view showing a further exemplary
embodiment of a label sheet for cleaning according to the
invention;
[0022] FIG. 6 is a sectional view showing another exemplary
embodiment of a conveying member having a cleaning function
according to the invention;
[0023] FIG. 7 is a partial plan view showing another exemplary
embodiment of a label sheet for cleaning according to the
invention; and
[0024] FIG. 8 is a sectional view taken along a line VIII-VIII of
FIG. 7.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION
[0025] Exemplary embodiments of the invention will now be described
below by reference to the attached Figures. The described exemplary
embodiments are intended to assist the understanding of the
invention, and are not intended to limit the scope of the invention
in any way.
[0026] According to an exemplary embodiment of the invention, in a
label sheet for cleaning, a cleaning layer (which hereinafter may
include such configurations as a single cleaning sheet, a laminated
sheet or a laminated sheet with a base material) is cured by an
active energy source (e.g., ultraviolet rays and/or heat),
resulting in a reduction in adhesion. As a result, a 180.degree.
peeling adhesion to a silicon wafer (mirror surface) of the
cleaning layer is set to 0.20 N/10 mm or less, and more preferably,
but not necessarily, is set to approximately 0.010 to 0.10 N/10 mm.
When the adhesion exceeds 0.20 N/10 mm, the cleaning layer might be
bonded to a portion to be cleaned in the equipment during
conveyance therein, which would result in conveyance troubles.
Moreover, while the thickness of the cleaning layer is not
particularly restricted, it is usually set to be approximately 5 to
100 .mu.m.
[0027] According to another exemplary embodiment of the invention,
the cleaning layer has a modulus of tensile elasticity (in
accordance with a test method JIS K7127) of 0.98 N/mm.sup.2 or more
and more preferably, but not necessarily, 9.8 to 980 N/mm.sup.2. If
the modulus of tensile elasticity is set in this manner, a
substrate can be conveyed more reliably in processing
equipment.
[0028] According to another exemplary embodiment of the invention
the cleaning layer should have a surface resistivity of
1.times.10.sup.13 .OMEGA./.quadrature. or more and more
particularly, but not necessarily, 1.times.10.sup.14
.OMEGA./.quadrature. or more. If the surface resistivity of the
cleaning layer is set in this manner, it is possible to obtain the
effect that foreign matter can be captured and adsorbed through
static electricity in addition to the adhesion thereof.
Accordingly, in another exemplary embodiment, the cleaning layer
does not include a conductive substance such as an additive having
a conducting function.
[0029] According to another exemplary embodiment of the invention,
a curing type adhesive which is polymerized and cured upon receipt
of an active energy is used for the cleaning layer. Consequently,
tackiness of the cleaning layer is substantially eliminated so that
the cleaning layer is not strongly bonded to the equipment when a
conveying member having a cleaning function is conveyed. Thus, it
is possible to provide the conveying member having a cleaning
function which can be conveyed reliably.
[0030] According to another exemplary embodiment of the invention,
the cleaning layer has such a property that it is cured by the
active energy source to cause a molecular structure to have a
three-dimensional network. As long as such a result is achieved,
the material of which the cleaning layer is constructed is not
particularly restricted. For example, the cleaning layer may be
formed of an adhesive layer obtained by a pressure-sensitive
adhesive polymer containing a compound having one or more
unsaturated double bonds in a molecule. Examples of such a
pressure-sensitive adhesive polymer include an acryl based polymer
containing, as a principal monomer, (metha)acrylic acid and/or
(metha)acrylic ester selected from acrylic acid, acrylic ester,
methacrylic acid and ester methacrylate. A compound having two or
more unsaturated double bonds in a molecule is used as a
copolymerized monomer in the synthesis of the acryl based polymer
or a compound having an unsaturated double bond in a molecule is
chemically bonded to the acryl based polymer with a reaction
between functional groups after the synthesis so that the
unsaturated double bond is introduced into the molecule of the
acryl based polymer. Consequently, a polymer itself can also be
related to a polymerization and curing reaction with an active
energy.
[0031] In this regard, a compound having one or more unsaturated
double bonds in a molecule (which will be hereinafter referred to
as a polymerized and unsaturated compound) should be a low
molecular weight compound which is nonvolatile and has a weight
average molecular weight of 10,000 or less, and particularly,
should have a weight average molecular weight of 5,000 or less such
that the three-dimensional network of an adhesive layer can be
obtained efficiently during curing. Examples of such a polymerized
compound include phenoxypolyethyleneglycol(metha)acrylate,
.epsilon.-caprolacton(metha)acrylate, polyethyleneglycol
di(metha)acrylate, polypropyleneglycol di(metha)acrylate,
trimethylolpropane tri(metha)acrylate, dipentaerythritol
hexa(metha)acrylate, urethane(metha)acrylate, epoxy(metha)acrylate
and oligoester(metha)acrylate, and one or more of them are
used.
[0032] Moreover, a polymerization initiator to be added to the
cleaning layer is not particularly restricted and a well-known
polymerization initiator can be used. For example, in the case in
which heat is used for the active energy source, a thermal
polymerization initiator such as benzoyl peroxide or
azobisisobutylonitoryl is applied. In the case in which light is
used for the active energy source, a photopolymerization initiator
such as benzoyl, benzoyl ethylether, dibenzyl, isopropylbenzoyl
ether, benzophenone, Michler's ketone chlorothioxanthone,
dodecylthioxanthone, dimethylthioxanthone, acetophenone
diethylketal, benzyldimethylketal, a-hydroxycyclohyxyl
phenylketone, 2-hydroxydimethyl phenylpropane or
2,2-dimethoxy-2-phenylacetophenone.
[0033] The label sheet for cleaning according to another exemplary
embodiment of the invention comprises a label for cleaning
including the specific cleaning layer on one of surfaces of a base
material and an ordinary adhesive layer on the other surface of the
base material. Further, the label sheet is removably provided on a
separator through the ordinary adhesive layer. In such an
embodiment, as long as the ordinary adhesive layer satisfies the
adhesion function, a material thereof is not particularly
restricted and an ordinary adhesive (for example, an acryl based
adhesive or a rubber based adhesive) can be used. Further, in such
an embodiment, the label sheet is removed from a separator (which
will be described below), is bonded to a conveying member such as a
substrate through the ordinary adhesive layer, and is conveyed as a
conveying member having a cleaning function into a piece of
equipment to come in contact with a portion to be washed. Thus, the
cleaning can be carried out.
[0034] In this embodiment, while the base material is not
particularly restricted, examples thereof include a plastic film
such as polyethylene, polyethylene terephthalate, acetyl cellulose,
polycarbonate, polypropylene or polyamide. A thickness of the base
material is usually set to approximately 10 to 100 .mu.m.
[0035] In this embodiment, as long as the label for cleaning can be
removed, the separator according to the invention is not
particularly restricted and examples thereof include polyolefin
such as polyester, polypropylene, polybutene, polybutadiene or
polymethyl pentene which is removed with a silicone based, long
chain alkyl based, fluorine based, fatty acid amide based or silica
based remover, and a plastic film formed of polyvinyl chloride,
vinyl chloride copolymer, polyethylene terephthalate, polybutylene
terephthalate, polyurethane, ethylene-vinylacetate copolymer,
ionomer resin, ethylene-(metha)acrylate copolymer,
ethylene-(metha)acrylic ester compolyer, polystyrene or
polycarbonate.
[0036] According to another exemplary embodiment of the invention,
when the label sheet is designed to be conveyed in a piece of
equipment on a substrate, and when the label sheet is removed from
the adhesive layer after the cleaning in order to recycle the
substrate, the ordinary adhesive layer should have a 180.degree.
peeling adhesion for a silicon wafer (mirror surface) of
approximately 0.01 to 0.98 N/10 mm, and more particularly, but not
necessarily, approximately 0.01 to 0.5 N/10 mm. When the peeling
adhesion is set in this manner, the substrate is not separated from
the label sheet during conveyance, but can be easily removed
therefrom after the cleaning.
[0037] In the embodiments described herein, the conveying member to
which the label for cleaning is to be bonded is not particularly
restricted. Examples of the conveying member include a
semiconductor wafer, a substrate for a flat panel display such as
an LCD or a PDP and a substrate for a compact disk or an MR
head.
[0038] The exemplary embodiments of the invention will now be
described with specific reference to the attached drawings, and in
view of the exemplary embodiments described above.
[0039] FIG. 1 is a plan view showing an exemplary embodiment of a
label sheet for cleaning according to the invention in which a
plurality of labels A for cleaning are continuously provided on an
elongated separator 1 at regular intervals. The label A includes a
cleaning layer 3 on one of surfaces of a base material 2 and an
ordinary adhesive layer 4 on the other surface, as shown in FIG. 2
(a sectional view taken along a line II-II in FIG. 1), and is
removably provided on the separator 1 through the adhesive layer
4.
[0040] During use, the label for cleaning is removed from the
separator 1, is bonded to a conveying member such as a
semiconductor wafer, and is conveyed into apiece of equipment.
Consequently, a portion to be washed can be cleaned.
[0041] FIG. 3 is a plan view showing another exemplary embodiment
of the label sheet for cleaning according to the invention in which
a reinforcing portion B is formed along the periphery of label A,
separated therefrom by a trench-shaped concave portion C. Since the
reinforcing portion B is provided, an excellent handling property
can be obtained when the label sheet for cleaning is a roll-shaped
substance or a sheet laminator, and the label for cleaning can be
smoothly removed from a separator during use so that an excellent
labeling reliability can also be obtained. In this embodiment, the
shapes of the labels A and reinforcing portions B may be obtained
by punching and removing an unnecessary part to form the concave
portion C. In this case, the concave portions C may be continuously
provided with each other to allowconsecutive removal.
Alternatively, a part of the periphery of the label A may be only a
nick portion so that the label A and the reinforcing portion B may
be provided partially in contact with each other.
[0042] FIG. 4 is a plan view showing another exemplary embodiment
of the label sheet for cleaning according to the invention in which
a band-shaped reinforcing portions B1 can be continuously provided
on both transverse sides of the separator 1. The reinforcing
portions B1 are formed linearly in parallel with the side of the
separator. The reinforcing portions B1 and the label A may be
separated at regular intervals from each other on one or both sides
of the separator 1 so that the unnecessary parts can be
consecutively removed during the manufacture of the sheet. However,
the reinforcing portions B1 and the label A on may also be provided
in contact with each other.
[0043] FIG. 5 is a plan view showing another exemplary embodiment
of the label sheet for cleaning according to the invention in which
a wider reinforcing portion B2 on one side of the separator 1 is
formed to have a greater width such that the reinforcing portion B1
provided on the opposite side of the separator. The wider
reinforcing portion B2 comes in contact with a part of the outer
periphery of the label A. Consequently, it is possible to further
enhance the effect of reinforcing the end of the label sheet
without damaging the continuous removal of the unnecessary
part.
[0044] While the shape of the reinforcing portion B is not
particularly restricted and can be properly provided continuously
or discontinuously, a continuous reinforcing portion B prevents
refuse from entering through the sides of the separator 1. Further,
although the thickness of the reinforcing portion B is not
particularly restricted, the thickness may be almost equal to that
of the label A in consideration of the roll-shaped or laminated
label sheet. Still further, the width of the reinforcing portion B
is not particularly restricted and can be properly set in
consideration of the width of the separator and the diameter of the
label. If the width is set to be as great as possible, the
reinforcing effect can be increased.
[0045] A method of manufacturing the label sheet for cleaning
according to the invention is not particularly restricted. Such a
method may include, for example, bonding an adhesive film
constituting the label and the reinforcing portion (in which a
cleaning layer is provided on one of surfaces of a base material
and an ordinary adhesive layer is provided on the other surface)
onto the separator. Next, only the adhesive film is punched to form
the shape(s) of the label and/or reinforcing portion simultaneously
or separately so that an unnecessary adhesive film can be separated
and removed from the separator. In this case, the concave portion
(e.g., C) may be provided continuously to allow the unnecessary
adhesive film to be removed consecutively. In such a process, the
cutting method or the processing configuration is not particularly
restricted. Then, the unnecessary adhesive film is usually wound
onto an optional core to be roll-shaped.
[0046] In another exemplary embodiment of the label sheet for
cleaning according to the invention, a curing type adhesive for
polymerizing and curing a cleaning layer upon receipt of an active
energy may be used and the step of cutting the sheet to have the
shape of the label should be carried out after the polymerization
and curing reaction of the adhesive of the cleaning layer. If the
adhesive constituting the cleaning layer is neither polymerized nor
cured during the sheet cutting, an adhesive layer constituting the
cleaning layer may protrude from a cut end and bond to a cut
surface, the adhesive may rope, a cutting depth may become
nonuniform, or a cut surface may be roughened. In the worst case,
defective cutting might be caused. Furthermore, when the
polymerization and curing reaction is carried out after the sheet
cutting, the adhesive facing a cut portion is inhibited from being
polymerized due to oxygen inhibition, which may consequently result
in the substrate processing equipment being contaminated by the
adhesive.
[0047] In another exemplary embodiment of the label sheet for
cleaning according to the invention, the cleaning layer has a
modulus of tensile elasticity (in accordance with a test method JIS
K7127) of 10 N/mm.sup.2 or more and preferably 10 to 2000
N/mm.sup.2 such that troubles are not made during the sheet
cutting. If the modulus of tensile elasticity is set to have such a
specific value or more, it is possible to better prevent the
adhesive from leaking out of the cleaning layer or a defective
cutting from being caused during the sheet cutting. Thus, it is
possible to manufacture a label sheet for cleaning which is not
contaminated by the adhesive in the precutting method. If the
modulus of tensile elasticity is smaller than 10 N/mm.sup.2, the
troubles might occur during the sheet cutting or conveyance
troubles might occur due to bonding of the adhesive to a portion to
be cleaned in the equipment during the conveyance. On the other
hand, if the modulus of tensile elasticity is too great, the
performance for removing foreign matters sticking onto a conveying
system might be deteriorated.
[0048] FIG. 6 shows an exemplary embodiment of the invention where
a label A for cleaning is provided on a conveying member W, such as
a wafer, so that the shape of the label A is smaller than that of
the conveying member W and is not protruded from the end of the
conveying member W. The label A includes a cleaning layer 3 on one
of surfaces of a base material 2 and an ordinary adhesive layer 4
on the other surface, and is provided on the conveying member W
through the adhesive layer 4.
[0049] Providing a label that is smaller and/or does not protrude
from a conveying member is advantageous because, if the cleaning
sheet is larger than the conveying member and/or is protruded from
the conveying member, the cleaning sheet may be caught in a
conveying member accommodating cassette or a conveyance path so
that it is turned over and shifted. In the worst case, there is a
possibility that the conveyance might not be carried out. Further,
the label sheet might even be caught in the conveying member
accommodating cassette even if the shape of the cleaning sheet is
the same as that of the conveying member. Only in the case in which
the shape of the cleaning sheet is smaller than that of the
conveying member, can these problems be totally avoided so that the
conveying member having a cleaning function can be conveyed
reliably. While the degree of smallness is not particularly
restricted, an effective area required for removing foreign matters
is reduced if the cleaning sheet is too small. Therefore, a size of
approximately 5 mm is practically required at a minimum.
[0050] FIG. 7 is a plan view showing another example of a label
sheet for cleaning according to the invention wherein a plurality
of labels A for cleaning continuously provided on an elongated
separator 1 at regular intervals. As described above, the shape of
the label A may be smaller than that of the conveying member W of
FIG. 6. In this case, the label A includes a cleaning layer 3 on
one of surfaces of a base material 2, a separating film 5 on a
surface thereof, and an ordinary adhesive layer 4 on the other
surface as shown in FIG. 8 (a sectional view taken along a line
VIII-VIII in FIG. 7) and is removably provided on the separator 1
through the adhesive layer 4.
[0051] During use, the label A for cleaning is removed from the
separator 1 and is bonded to the conveying member W (such as a
semiconductor wafer), and furthermore, the separating film 5 is
removed and the label A for cleaning is thus conveyed into a piece
of equipment. Consequently, a portion to be washed can be
cleaned.
[0052] In the embodiments described herein, the shape of the label
A is not particularly restricted. The label A may be a circular
shape, a wafer shape, a frame shape, or a shape having a protruded
part for a chuck portion, depending on the shape of the conveying
member such as, for example, a substrate to be bonded. Further, as
described above, the label A may be smaller than the shape of the
conveying member W.
[0053] The invention will be further described below based on a
discussion of three example constructions, along with comparisons
thereto. These examples should not be read as restricting the
invention in any way. In the following description, a "part"
represents a "part by weight".
FIRST EXAMPLE
[0054] An adhesive solution of an ultraviolet curing type was
prepared by uniformly mixing 50 parts by weight of
polyethyleneglycol dimethacrylate, 50 parts by weight of urethane
acrylate, 3 parts by weight of benzyldimethyl ketal and 3 parts by
weight of diphenylmethane diisocyanate with 100 parts by weight of
acryl based polymer (a weight average molecular weight of 700000)
obtained by a monomer mixed solution containing 75 parts by weight
of acrylic acid-2-ethylhexyl, 20 parts by weight of methyl acrylate
and 5 parts by weight of acrylic acid.
[0055] Additionally, an ordinary adhesive solution was prepared in
the same manner as described above except that the benzyldimethyl
ketal was excluded from the adhesive.
[0056] The ordinary adhesive solution was coated to have a
thickness of 10 .mu.m after drying over the removed surface of a
separator formed of an elongated polyester film (with a thickness
of 38 .mu.m and a width of 250 mm) having one surface treated with
a silicone based remover. An elongated polyolefin film (with a
thickness of 25 .mu.m and a width of 250 mm) was then provided on
the ordinary adhesive layer, and an adhesive solution of an
ultraviolet curing type was coated over the polyolefin film to have
a thickness of 40 .mu.m after drying. Thus, a sheet was
obtained.
[0057] Ultraviolet rays having a central wavelength of 365 nm were
irradiated on the sheet with an integral light quantity of 1000
mJ/cm.sup.2 so that a sheet for cleaning having a cleaning layer
cured by the ultraviolet rays was obtained.
[0058] The top portion of the sheet (other than the separator) was
punched to form a circle having a diameter of 200 mm, and an
unnecessary part of the sheet was continuously separated and
removed. Thus, the label sheet for cleaning according to the
exemplary embodiment of the invention shown in FIG. 1 was
fabricated.
[0059] A cleaning layer of the cleaning sheet was bonded to the
mirror surface of a silicon wafer with a width of 10 mm and a
180.degree. peeling adhesion to the silicon wafer was measured in
accordance with JIS Z0237. As a result, a 180.degree. peeling
adhesion of 0.078 N/10 mm was measured.
[0060] The cleaning layer of the cleaning sheet had a modulus of
tensile elasticity of 49 N/mm.sup.2. The modulus of tensile
elasticity was measured in accordance with a test method JIS
K7127.
[0061] Moreover, a surface resistivity was measured over the
cleaning layer with surface resistivity measuring equipment
(produced by Mitsubishi Chemical Corporation, Type of MCP-UP450) at
a temperature of 23.degree. C. and a humidity of 60% RH. As a
result, 9.99.times.10.sup.13 .OMEGA./.quadrature. or more was
obtained and the measurement could not be carried out.
[0062] A label for cleaning was removed from the separator and was
bonded to the back face (mirror surface) of a silicon wafer having
a size of 8 inches with a hand roller. Thus, a cleaning wafer for
conveyance having a cleaning function was fabricated.
[0063] Then, two wafer stages of the substrate processing equipment
were removed and foreign matters having a size of 0.3 .mu.m or more
were measured through lasertype foreign matter measuring equipment.
20000 foreign matters were measured in an area having a wafer size
of 8 inches and 18000 foreign matters were measured in another
area.
[0064] Next, the cleaning wafer was conveyed into the substrate
processing equipment having the wafer stage to which the 20000
foreign matters stuck. The conveyance could be carried out without
a hindrance. Then, the wafer stage was removed and the foreign
matters having a size of 0.3 .mu.m or more were again measured
through the laser type foreign matter measuring equipment. 3950
foreign matters were measured within a wafer size of 8 inches.
Thus, 3/4 or more of the foreign matter which stuck before the
cleaning were removed.
COMPARATIVE EXAMPLE 1
[0065] A cleaning sheet was fabricated in the same manner as that
in the first embodiment except that ultraviolet rays having a
central wavelength of 365 nm were irradiated with an integral light
quantity of 150 mJ/cm.sup.2. An adhesion to a silicon wafer was
measured. As a result, an adhesion of 0.33 N/10 mm was
obtained.
[0066] A cleaning wafer for conveyance which was fabricated from
the cleaning sheet in the same method as that in the embodiment was
conveyed into a substrate processing equipment having a wafer stage
to which 18000 foreign matters stuck. As a result, the cleaning
wafer was fastened to the wafer stage and could not be
conveyed.
SECOND EXAMPLE
[0067] An adhesive solution of an ultraviolet curing type was
prepared by uniformly mixing 50 parts by weight of
polyethyleneglycol 200 dimethacrylate (produced by SHIN-NAKAMURA
CHEMICAL CO., LTD: trade name of Nk Ester 4G), 50 parts by weight
of urethane acrylate (produced by SHIN-NAKAMURA CHEMICAL CO., LTD:
trade name of U-N-01), 3 parts by weight of polyisocyanate compound
(produced by NIPPON POLYURETHANE INDUSTRY CO., LTD: trade name of
Colonate L) and 3 parts by weight of benzyldimethyl ketal as a
photopolymerization initiator (produced by CIBA SPECIALTY CHEMICALS
K.K.: trade name of Irugacure-651) with 100 parts by weight of
acryl based polymer (a weight average molecular weight of 700000)
obtained by a monomer mixed solution containing 75 parts by weight
of acrylic acid-2-ethylhexyl, 20 parts by weight of methyl acrylate
and 5 parts by weight of acrylic acid.
[0068] Additionally, an ordinary adhesive solution was obtained in
the same manner as described above except that the benzyldimethyl
ketal was excluded from the adhesive.
[0069] The ordinary adhesive solution was coated to have a
thickness of 10 .mu.m after drying over the removed surface of a
separator formed of an elongated polyester film (with a thickness
of 38 .mu.m and a width of 250 mm) having one surface treated with
a silicone based remover. An elongated polyester film (with a
thickness of 25 .mu.m and a width of 250 mm) was provided on the
ordinary adhesive layer, and an adhesive solution of an ultraviolet
curing type was coated over the polyester film to have a thickness
of 40 .mu.m after drying. Thus, an adhesive layer was provided as a
cleaning layer, and a removing film formed of the elongated
polyester film (with a thickness of 38 .mu.m and a width of 250
mm), having one of surfaces treated with a silicone based remover,
was bonded to the surface of the adhesive layer. Thus, a sheet was
obtained.
[0070] Ultraviolet rays having a central wavelength of 365 nm were
irradiated on the sheet with an integral light quantity of 1000
mJ/cm.sup.2 so that a sheet for cleaning having a cleaning layer
cured by the ultraviolet rays was obtained.
[0071] The top portion of the sheet (other than the separator) was
punched to form a circle having a diameter of 198 mm, and an
unnecessary part of the sheet was continuously separated and
removed. Thus, the label sheet for cleaning according to the
exemplary embodiment of the invention shown in FIG. 7 was
fabricated. Moreover, the cleaning layer of the label sheet for
cleaning had a modulus of tensile elasticity of 49 N/mm.sup.2 after
the curing through the irradiation of the ultraviolet rays. The
modulus of tensile elasticity was measured in accordance with a
test method JIS K7127.
[0072] The label for cleaning was removed from the separator of the
label sheet for cleaning thus obtained and was bonded to the back
face (mirror surface) of a silicon wafer having a size of 8 inches
(200 mm) with a hand roller. Thus, a cleaning wafer for conveyance
having a cleaning function was fabricated.
[0073] By using the label sheet for cleaning, the label was bonded
to the back face (mirror surface) of the silicon wafer having a
size of 8 inches through a label tape bonding machine (produced by
NITTO SEIKI INC.: trade name of NEL-GR3000). This operation was
carried out continuously for 25 sheets. As a result, the sheet
could be bonded to the wafer without a problem. Thus, a cleaning
wafer for conveyance having a cleaning function could be
fabricated. Moreover, the cleaning wafer for conveyance having a
cleaning function thus obtained was confirmed, and it was found
that all the label sheets are bonded to the inside of the silicon
wafer and were not protruded from the end of the wafer.
[0074] Moreover, the cleaning layer was bonded to the mirror
surface of the silicon wafer with a width of 10 mm and a
180.degree. peeling adhesion to the silicon wafer was measured in
accordance with JIS Z0237. As a result, the 180.degree. peeling
adhesion to the silicon wafer was 0.078 N/10 mm.
[0075] On the other hand, foreign matters having a size of 0.2
.mu.m or more were measured over the mirror surfaces of two
brand-new silicon wafers having a size of 8 inches through a laser
type foreign matter measuring equipment. Consequently, a first
wafer had six foreign matters and a second wafer had five foreign
matters. After the wafers are conveyed to a substrate processing
equipment having separate electrostatic adsorbing mechanisms with
the mirror surfaces put on the underside and the foreign matters
having a size of 0.2 .mu.m or more were measured through the laser
type foreign matter measuring equipment. Consequently, a first
wafer had 33456 foreign matters in an area having a wafer size of 8
inches and a second wafer had 36091 foreign matters.
[0076] Next, a removing film on the cleaning layer side of the
cleaning wafer for conveyance obtained as described above was
removed and was conveyed into the substrate processing equipment
having a wafer stage to which the 33456 foreign matters stuck. The
conveyance could be carried out without a hindrance. Then, a
brand-new silicon wafer having a size of 8 inches was conveyed with
a mirror surface put on the underside and foreign matters having a
size of 0.2 .mu.m or more were measured through the laser type
foreign matter measuring equipment. This operation was carried out
five times and a ratio of foreign matter removal is shown in Table
1.
TABLE-US-00001 TABLE 1 Ratio of foreign matter removal 1 sheet 2
sheets 3 sheets 4 sheets 5 sheets convey- convey- convey- convey-
convey- ance ance ance ance ance Second 80% 88% 90% 92% 92%
embodiment
COMPARATIVE EXAMPLE 2
[0077] A cleaning wafer for conveyance having a cleaning function
was fabricated in the same manner as that in the second example
except that a label sheet for cleaning obtained through punching
into a circular shape having a diameter of 202 mm was used. The
wafer was confirmed through a microscope and it was found that the
label sheet for cleaning was protruded from the outer peripheral
portion of the silicon wafer.
[0078] A separating film on the cleaning layer side of the cleaning
wafer for conveyance was removed and was set onto a wafer cassette
to be conveyed into a substrate processing equipment. Consequently,
the protruded label sheet came in contact with the internal wall of
the cassette and the cleaning wafer itself for conveyance was
shifted from a regular position in the wafer cassette. Therefore,
the conveyance could not be carried out. Accordingly, the
conveyance using the cleaning wafer for conveyance was stopped.
THIRD EXAMPLE
[0079] An adhesive solution of an ultraviolet curing type was
prepared by uniformly mixing 50 parts by weight of
polyethyleneglycol 200 dimethacrylate (produced by SHIN-NAKAMURA
CHEMICAL CO., LTD: trade name of Nk Ester 4G), 50 parts by weight
of urethane acrylate (produced by SHIN-NAKAMURA CHEMICAL CO., LTD:
trade name of U-N-01), 3 parts by weight of polyisocyanate compound
(produced by NIPPON POLYURETHANE INDUSTRY CO., LTD: trade name of
Colonate L) and 3 parts by weight of benzyldimethyl ketal as a
photopolymerization initiator (produced by CIBA SPECIALTY CHEMICALS
K.K.: trade name of Irugacure-651) with 100 parts by weight of
acryl based polymer (a weight average molecular weight of 700000)
obtained by a monomer mixed solution containing 75 parts by weight
of acrylic acid-2-ethylhexyl, 20 parts by weight of methyl acrylate
and 5 parts by weight of acrylic acid.
[0080] Additionally, an ordinary adhesive solution was obtained in
the same manner as described above except that the benzyldimethyl
ketal was excluded from the adhesive.
[0081] The ordinary adhesive solution was coated to have a
thickness of 10 .mu.m after drying over the removed surface of a
separator formed of an elongated polyester film (with a thickness
of 38 .mu.m and a width of 250 mm) having one surface treated with
a silicone based remover. An elongated polyester film (with a
thickness of 25 .mu.m and a width of 250 mm) was then provided on
the ordinary adhesive layer, and an adhesive solution of an
ultraviolet curing type was coated over the polyolefin film to have
a thickness of 40 .mu.m after drying. Thus, an adhesive layer was
provided as a cleaning layer, and a removing film formed of the
elongated polyester film (with a thickness of 38 .mu.m and a width
of 250 mm), having one of surfaces treated with a silicone based
remover, was bonded to the surface of the adhesive layer. Thus, a
sheet was obtained.
[0082] Ultraviolet rays having a central wavelength of 365 nm were
irradiated on the sheet with an integral light quantity of 1000
mJ/cm.sup.2 so that a sheet for cleaning having a cleaning layer
cured by the ultraviolet rays was obtained.
[0083] The top portion of the sheet (other than the separator) was
punched to form a circle having a diameter of 200 mm, and an
unnecessary part of the sheet was continuously separated and
removed. Thus, the label sheet for cleaning according to the
invention shown in FIG. 1 was fabricated. The processing of
punching the cleaning sheet could be carried out without generation
of adhesive roping and a cut refuse. After the fabrication, the
label sheet was observed and it was found that the adhesive was not
protruded from the end of the label and the label was not
contaminated by the adhesive.
[0084] Moreover, the cleaning layer of the sheet for cleaning had a
modulus of tensile elasticity of 49 N/mm.sup.2 after the curing
through the irradiation of the ultraviolet rays, that is, the sheet
punching. The modulus of tensile elasticity was measured in
accordance with a test method JIS K7127.
[0085] The label for cleaning was removed from the separator of the
label sheet having a cleaning function thus obtained and was bonded
to the back face (mirror surface) of a silicon wafer having a size
of 8 inches with a hand roller. Thus, a cleaning wafer for
conveyance having a cleaning function was fabricated.
[0086] By using the label sheet having a cleaning function, the
label was bonded to the back face (mirror surface) of the silicon
wafer having a size of 8 inches through a label tape bonding
machine (produced by NITTO SEIKI INC.: trade name of NEL-GR3000).
This operation was carried out continuously for 25 sheets. As a
result, the sheet could be bonded to the wafer without a problem.
Thus, a cleaning wafer for conveyance having a cleaning function
could be fabricated. Moreover, the cleaning layer was bonded to the
mirror surface of the silicon wafer with a width of 10 mm and a
180.degree. peeling adhesion to the silicon wafer was measured in
accordance with JIS Z0237. As a result, the 180.degree. peeling
adhesion to the silicon wafer was 0.078 N/10 mm.
[0087] On the other hand, foreign matters having a size of 0.2
.mu.m or more were measured over the mirror surfaces of two
brand-new silicon wafers having a size of 8 inches through a laser
type foreign matter measuring equipment. Consequently, a first
wafer had six foreign matters and a second wafer had five foreign
matters. After the wafers are conveyed to a substrate processing
equipment having separate electrostatic adsorbing mechanisms with
the mirror surfaces put on the underside and the foreign matters
having a size of 0.2 .mu.m or more were measured through the laser
type foreign matter measuring equipment. Consequently, a first
wafer had 33456 foreign matters in an area having a wafer size of 8
inches and a second wafer had 36091 foreign matters.
[0088] Next, a removing film on the cleaning layer side of the
cleaning wafer for conveyance obtained as described above was
removed and was conveyed into the substrate processing equipment
having a wafer stage to which the 33456 foreign matters stuck. The
conveyance could be carried out without a hindrance. Then, a
brand-new silicon wafer having a size of 8 inches was conveyed with
a mirror surface put on the underside and foreign matters having a
size of 0.2 .mu.m or more were measured through the laser type
foreign matter measuring equipment. This operation was carried out
five times and a ratio of foreign matter removal is shown in Table
2.
TABLE-US-00002 TABLE 2 Ratio of foreign matter removal 1 sheet 2
sheets 3 sheets 4 sheets 5 sheets convey- convey- convey- convey-
convey- ance ance ance ance ance Third 80% 88% 90% 92% 92%
embodiment
COMPARATIVE EXAMPLE 3
[0089] A cleaning sheet was fabricated in the same manner as that
in the third example except that ultraviolet rays having a central
wavelength of 365 nm were not irradiated on the cleaning sheet with
an integral light quantity of 1000 mJ/cm.sup.2. The sheet was cut
through punching into a circular shape having a diameter of 200 mm
in the same manner as that in the embodiment. Thus, a label sheet
having a cleaning function was fabricated. In this case, since the
cleaning layer was not cured, it served as a cushioning material.
Consequently, a punching depth was not uniform so that a large
number of punching defects of the label were generated. Moreover,
the label thus fabricated was observed and it was found that an
adhesive leaked out of the end of the label. Furthermore, many
portions on the label were contaminated by the adhesive due to
adhesive roping during the punching. In particular, moreover, the
adhesive stuck onto a removing film around the cleaning layer side
at the end of the label. After the label was fabricated, the
ultraviolet rays having a central wavelength of 365 nm were
irradiated with an integral light quantity of 1000 mJ/cm.sup.2.
However, the adhesive on the end of the label was not cured due to
oxygen inhibition but had tackiness. Accordingly, the fabrication
of a cleaning wafer for conveyance using the label sheet was
stopped.
INDUSTRIAL APPLICABILITY
[0090] According to the cleaning sheet of the invention, as
described above, conveyance in a substrate processing equipment can
be carried out reliably and foreign matter sticking into the
equipment can be removed easily and reliably. Furthermore, since
sheet cutting is not required after bonding to a substrate, a
working efficiency can be enhanced and a cut refuse is not
generated.
[0091] Although the invention has been described in its preferred
form with a certain degree of particularity, it is understood that
the present disclosure of the preferred form can be changed in the
details of construction and in the combination and arrangement of
parts without departing from the spirit and the scope of the
invention as hereinafter claimed.
* * * * *