JP2001198540A - Cleaning sheet - Google Patents

Abstract

(57) Abstract: The present invention provides a cleaning sheet for a substrate processing apparatus that rejects foreign matter, such as a manufacturing apparatus or an inspection apparatus for semiconductors, flat panel displays, printed boards, and the like. SOLUTION: The support is provided with a cleaning layer having substantially no tackiness and having a tensile modulus of elasticity of 0.98 N / mm ² or more (according to test method JIS K7127), or the other surface. Is a cleaning sheet provided with a normal pressure-sensitive adhesive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet for cleaning various devices, and more particularly, to a cleaning sheet for a substrate processing apparatus which does not like foreign substances, such as a manufacturing apparatus and an inspection apparatus for semiconductors, flat panel displays and printed circuit boards.

[0002]

2. Description of the Related Art Various substrate processing apparatuses transport substrates while physically contacting each transport system with a substrate. At that time, if foreign matter is attached to the substrate or the transport system, the subsequent substrate is contaminated one after another, and it is necessary to periodically stop the apparatus and perform a cleaning process. For this reason, there has been a problem that the operation rate is reduced and a large amount of labor is required. In order to solve these problems, there has been proposed a method of cleaning and removing adhered foreign matter in a substrate processing apparatus by transporting a substrate to which an adhesive substance is adhered (for example, Japanese Patent Application Laid-Open No. H10-15).
No. 4686).

[0003]

The method of cleaning and removing the adhered foreign matter in the substrate processing apparatus by transporting the substrate to which the adhesive substance is fixed is an effective method for overcoming the above-mentioned problem. However, in this method, the sticky substance and the device contact portion may be so strongly adhered that they cannot be peeled off, and the substrate may not be transported reliably. The present invention has been made in view of the above circumstances, and has as its object to provide a cleaning sheet that can reliably transport a substrate into a substrate processing apparatus and that can easily and surely remove foreign substances attached to the apparatus.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, by transporting a sheet to which a cleaning layer is fixed or a substrate to which this sheet is fixed, the substrate processing is performed. In cleaning and removing foreign substances attached to the apparatus, the cleaning layer has substantially no tackiness and its tensile modulus is set to a specific value or more, so that the above-described problem does not occur and foreign substances can be further simplified. The inventors have found that they can be reliably removed, and have completed the present invention.

That is, according to the present invention, the support has substantially no tackiness and a tensile modulus (test method JIS K7127).
A cleaning sheet provided with a cleaning layer having a thickness of 0.98 N / mm ² or more (according to JIS K7127), having substantially no tackiness on one side of the support and having a tensile modulus of elasticity (test method JIS K7127). 0.98 N / mm
^A cleaning sheet comprising ^two or more cleaning layers and a normal pressure-sensitive adhesive layer on the other surface (Claim 2). The cleaning layer comprises a pressure-sensitive adhesive polymer having one unsaturated double bond in the molecule. A cleaning sheet (Claim 3) in which a compound containing at least a compound having at least one and a polymerization initiator is subjected to a polymerization-curing reaction with active energy to substantially eliminate tackiness, and further, the surface resistivity of the cleaning layer is reduced. A cleaning sheet having a resistivity of 1 × 10 ¹³ Ω / □ or more (Claim 4), and a cleaning agent having a 180 ° peeling adhesive force of 0.21 to 0.98 N / 10 mm with respect to a silicon wafer (mirror surface) of a normal adhesive layer. It relates to a sheet (Claim 5).

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The cleaning sheet of the present invention
A cleaning layer is provided on one side of the support, and the cleaning layer has a tensile elasticity (test method JIS K7127).
0.98 N / mm ² or more, and preferably 9.9 N / mm ² .
It needs to be 8 to 3000 N / mm ² . When the tensile elastic modulus is less than 0.98 N / mm ² , the cleaning layer becomes tacky, and may adhere to a portion to be cleaned in the apparatus at the time of transport, causing a transport trouble.

As long as the cleaning layer has a tensile modulus equal to or higher than the specific value described above and does not substantially have tackiness,
The material and the like are not particularly limited, but those which can promote a crosslinking reaction and curing by an active energy source such as ultraviolet light or heat and increase the tensile elastic modulus thereof are preferable. further,
The cleaning layer has a surface resistivity of 1 × 10 ¹³ Ω /.
It is desirably at least □, preferably at least 1 × 10 ¹⁴ Ω / □. By designing the surface resistivity of the cleaning layer to be equal to or more than the specific value and making the cleaning layer an insulator as much as possible, it is possible to obtain an effect that foreign matter can be captured and adsorbed by static electricity. Therefore, the surface resistivity is 1 × 1
If it is less than 0 ¹³ Ω / □, the effect of capturing and adsorbing foreign matter due to such static electricity is significantly reduced.

As such a cleaning layer, for example, a pressure-sensitive adhesive polymer containing at least a compound having at least one unsaturated double bond in a molecule and a polymerization initiator is subjected to a polymerization curing reaction by active energy. It is preferable that the tackiness is substantially eliminated. Examples of such a pressure-sensitive adhesive polymer include acrylic polymers having a main monomer of (meth) acrylic acid and / or (meth) acrylic ester selected from acrylic acid, acrylic ester, methacrylic acid, and methacrylic ester. Can be In synthesizing this acrylic polymer, a compound having two or more unsaturated double bonds in the molecule is used as a copolymerization monomer, or a compound having an unsaturated double bond in the molecule is synthesized from the synthesized acrylic polymer. By introducing an unsaturated double bond into the molecule of the acrylic polymer, for example, by chemically bonding through a reaction between functional groups, the polymer itself can be involved in the polymerization curing reaction by active energy. Can also.

The compound having one or more unsaturated double bonds in the molecule (hereinafter referred to as a polymerizable unsaturated compound) is a low molecular weight compound which is nonvolatile and has a weight average molecular weight of 10,000 or less. In particular, the adhesive layer preferably has a molecular weight of 5,000 or less so that the three-dimensional network of the adhesive layer at the time of curing can be efficiently formed.

The polymerization initiator to be added to the cleaning layer is not particularly limited, and a known initiator can be used. For example, when heat is used as an active energy source, benzoyl peroxide, azobisisobutyronitrile, etc. When a thermal polymerization initiator or light is used, benzoyl, benzoin ethyl ether, cibenzyl, isopropyl benzoin ether, benzophenone, Michler's ketone chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, acetophenone diethyl ketal, benzyl dimethyl ketal, α-hiddle Photopolymerization initiators such as xycyclohexylphenyl ketone, 2-hydroxydimethylphenylpropane, and 2,2-dimethoxy-2-phenylacetophenone are exemplified. The thickness of the cleaning layer is not particularly limited, but is usually about 5 to 100 μm.

The present invention also provides a cleaning sheet in which the above-mentioned specific cleaning layer is provided on one side of a support and the ordinary pressure-sensitive adhesive layer is provided on the other side. The material of the pressure-sensitive adhesive layer on the other side is not particularly limited as long as it satisfies the pressure-sensitive adhesive function, and a normal pressure-sensitive adhesive (for example, acrylic or rubber-based) can be used. With this configuration, the cleaning sheet is attached to a transport member such as various substrates or other tapes / sheets with a normal adhesive layer, and is transported into the apparatus as a transport member with a cleaning function (Claim 6). Alternatively, cleaning can be performed by contacting the part to be cleaned (claim 7).

In the present invention, when the substrate is peeled off from the pressure-sensitive adhesive layer after cleaning in order to reuse the transfer member such as the substrate, the adhesive force of the normal pressure-sensitive adhesive layer is determined by a silicon wafer (mirror surface). 180 ° peeling strength to 0.21 to 0.98 N / 10 mm (Claim 5), especially about 0.40 to 0.98 N / 10 mm, without peeling during transportation and after cleaning It is preferable because it can be easily removed again.

The support for the cleaning layer is not particularly limited, and examples thereof include plastic films such as polyethylene, polyethylene terephthalate, acetylcellulose, polycarbonate, polypropylene and polyamide. Its thickness is usually 10 to 10
It is about 0 μm.

The transport member to which the cleaning sheet is adhered is not particularly limited, and examples thereof include semiconductor wafers, substrates for flat panel displays such as LCDs and PDPs, and other substrates such as compact disks and MR heads.

[0015]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Hereinafter, “parts” means “parts by weight”. Example An acrylic polymer (weight average molecular weight 70) obtained from a monomer mixture consisting of 75 parts of 2-ethylhexyl acrylate, 20 parts of methyl acrylate, and 5 parts of acrylic acid
100 parts), uniformly mix 50 parts of polyethylene glycol dimethacrylate, 50 parts of urethane acrylate, 3 parts of benzyl dimethyl ketal, and 3 parts of diphenylmethane diisocyanate, and cure by ultraviolet light. A mold-type adhesive solution was obtained. The tensile elasticity after curing the adhesive by irradiating it with ultraviolet light having a central wavelength of 365 nm and an integrated light quantity of 1000 mJ / cm ² was 49 N / mm ² . Here, the tensile modulus was measured according to the test method JIS K7127. On the other hand, a pressure-sensitive adhesive solution obtained in the same manner as described above, except that benzyldimethyl ketal was removed from the pressure-sensitive adhesive, was dried to a thickness of 10 μm on a release surface of a polyester release film having a width of 250 mm and a thickness of 38 μm. To form an ordinary pressure-sensitive adhesive layer. Next, on the release surface of a 38 μm-thick polyester release film, the above-mentioned ultraviolet-curable pressure-sensitive adhesive solution was applied so as to have a thickness of 40 μm after drying, and a cleaning layer was provided. Was adhered to the surface. Ultraviolet light having a central wavelength of 365 nm is applied to this sheet at an integrated light amount of 1000 mJ / cm.
^{After 2} irradiations, a cleaning sheet of the present invention was obtained. The surface of such a cleaning layer had substantially no tackiness. When the surface resistivity was measured from above the cleaning layer with a surface resistivity meter (Model MCP-UP450, manufactured by Mitsubishi Chemical Corporation) under the conditions of a temperature of 23 ° C. and a humidity of 60% RH, it was 9.99 × 10 ¹³ Ω. The measurement was impossible at // or more.
Further, the normal pressure-sensitive adhesive layer on the other side was adhered to the mirror surface of the silicon wafer with a width of 10 mm, and the 180 ° peeling strength of the silicon wafer with respect to the silicon wafer was measured according to JISZ0237. As a result, it was 0.25 N / 10 mm. .

The release film on the normal pressure-sensitive adhesive layer side of the cleaning sheet was peeled off and affixed to the back surface (mirror surface) of an 8-inch silicon wafer with a hand roller to produce a transport cleaning wafer having a cleaning function.

On the other hand, the wafer stage of the substrate processing apparatus is
When a foreign substance having a size of 0.3 μm or more was measured using a laser type foreign substance measuring apparatus, one of the 18,000 pieces and one of the foreign substances were 17000 in an 8-inch wafer size area.
Was individual.

Next, the release film on the cleaning layer side of the cleaning wafer for transfer obtained above was peeled off, and was transferred into a substrate processing apparatus having a wafer stage to which 18,000 foreign substances had adhered. Was. After that, the wafer stage was removed, and a foreign substance having a size of 0.3 μm or more was measured with a laser type foreign substance measuring apparatus. Could be removed.

COMPARATIVE EXAMPLE In the examples, benzyldimethyl ketal was added at 0.05%.
The cleaning layer of the cleaning sheet prepared in the same manner as in the example except that the cleaning layer had an adhesive portion was tacky, and its tensile modulus was measured to be 0.5 N / mm ² .
When a transfer cleaning wafer produced in the same manner as in the example from this cleaning sheet was transferred in a substrate processing apparatus having a wafer stage to which 17000 foreign substances were attached, it was adhered to a transfer arm and could not be transferred. .

[0020]

As described above, according to the cleaning sheet of the present invention, the inside of the substrate processing apparatus can be reliably transported, and the foreign substances adhering to the apparatus can be easily and reliably removed.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // A47L 25/00 A47L 25/00 B F term (reference) 3B116 AA02 AA03 AA46 AB01 BC01 BC07 4J004 AA05 AA10 AB01 AB07 CA02 CA04 CA06 CC03 EA06 FA04 FA05 FA10 5F031 CA02 CA04 CA11 FA01 FA02 MA37 PA24

Claims (7)

[Claims] 1. A cleaning sheet comprising a support and a cleaning layer having substantially no tackiness and having a tensile elasticity of 0.98 N / mm ² or more (according to JIS K7127). ^2. A cleaning layer having substantially no tackiness and having a tensile modulus of elasticity of 0.98 N / mm ² or more (according to JIS K7127) is provided on one surface of the support,
A cleaning sheet having a normal pressure-sensitive adhesive layer provided on the other surface. 3. A cleaning layer comprising a pressure-sensitive adhesive polymer containing at least a compound having at least one unsaturated double bond in a molecule and a polymerization initiator, which is subjected to a polymerization-curing reaction by active energy to form an adhesive. 3. The cleaning sheet according to claim 1, wherein the cleaning property is substantially lost. 4. The cleaning layer having a surface resistivity of 1 × 10
The cleaning sheet according to claim 1, wherein the cleaning sheet has a resistance of ¹³ Ω / □ or more. 5. An adhesive layer having a 180 ° peeling adhesive force of 0.21 to a silicon wafer (mirror surface) of a normal adhesive layer.
The cleaning sheet according to claim 2, wherein the thickness is 0.98 N / 10 mm. 6. A transport member with a cleaning function, wherein the cleaning sheet according to claim 2 is provided on the transport member by a normal pressure-sensitive adhesive layer. 7. A cleaning method, wherein the transfer member with a cleaning function according to claim 6 is brought into contact with a portion to be cleaned.