WO2000044544A1

WO2000044544A1 - Fluorine-containing elastomer moldings and method for preparing the same

Info

Publication number: WO2000044544A1
Application number: PCT/JP2000/000370
Authority: WO
Inventors: Hiroyuki Tanaka; Katsuhiko Higashino; Tsuyoshi Noguchi
Original assignee: Daikin Industries, Ltd.
Priority date: 1999-01-29
Filing date: 2000-01-26
Publication date: 2000-08-03

Abstract

Fluorine-containing elastomer moldings being free of a release agent which may be prepared by molding a fluorine-containing elastomer with the use of a mold coated with a fluororesin and with no release agent. The elastomer moldings can be used for improving the degree of cleanliness of fluorine-containing elastomer moldings for semiconductor equipment.

Description

Akira Itoda Fluoro-based elastomer ___ Molded article and its manufacturing method Technical field

The present invention relates to a fluorine-based elastomer molded article and a method for producing the same. More particularly, the present invention relates to a fluorine-based elastomer molded article which does not contain a release agent and is suitable as a component for a semiconductor manufacturing apparatus and a method of manufacturing the same. . Background technology

Conventionally, in the field of the semiconductor industry, molded products such as sealants for semiconductor manufacturing equipment generally include silicone-based materials and fluoropolymers. A system consisting of a silicone material, an ethylene propylene / gene ternary copolymer (EPDM), etc.

-Although steel materials are used, they are particularly strict in terms of operating conditions because they are superior in heat resistance, plasma resistance, corrosion gas resistance, etc. Examples of molded articles of vinylidene fluoride copolymer include hexafluorofluoropropylene copolymer rubber and hydridene fluoride Z tetrafluoroethylene copolymer rubber, tetrafluoropropylene copolymer rubber, tetrafluoroethylene Z Fluorine-based elastomers such as copolymer rubber, tetrafluoroethylene ethylene Z-propylene copolymer rubber, etc.ー Materials are used

In the process of manufacturing semiconductors, residues such as residue from photo resists, residues from organic solvents, synthetic waxes, fatty acids from the human body, etc. Inorganic contaminants such as organic residues, sodium, calcium, gold, iron, copper, etc., and fine particles Cracks occur. Since it is important to remove these and not to carry them into the subsequent high-temperature heat treatment process, the cleaning of wafers is particularly nervous. Strict control of the chemicals used for it is required.

However, for example, since the minimum noise of a 64 kbit DRAM is 2 to 3 m, it is necessary to control the particle size to about 0.2 to 0.3 mm. It is technically necessary to control chemicals used for cleaning wafers to a submicron level. At present, it is difficult.

Therefore, the inventors of the present invention believe that cleaning and cleaning of semiconductor products (workpieces) such as silicon wafers by etching and cleaning. We thought that this alone would not be enough, so we focused on cleaning the molding materials that make up the semiconductor manufacturing equipment, especially the sealing materials.

Particular attention was paid to molded products such as seal materials used in semiconductor manufacturing equipment because particles and metal components adhere to the semiconductor surface and reduce the yield. It is a car that was thought to be the cause.

As a method for cleaning molded articles such as sealing materials, conventionally, for example, a solvent such as isopropyl alcohol has been impregnated into absorbent cotton or the like. In general, the method of wiping with absorbent cotton has been used, but the amount of particles attached to the molded product and the content of metal components are still sufficient. In addition, even if the above-mentioned chemicals used for cleaning wafers or the like are used, the integration and patterning of semiconductors cannot be reduced. Sufficient cleaning has not been achieved in response to the miniaturization of screens. In view of the above facts, the present inventors have developed a new type of fluoroelastomer molded article for a clean semiconductor manufacturing apparatus. Developed an effective cleaning method (wo

9 9 4 9 9 9 7 pan fret).

Such a washing method involves the removal of 300 fine particles having a metal content of 1.0 ppm or less and a particle size of 0.2 m or more.

A method of washing a fluororubber molded article several times with ultrapure water containing no more than 1; the metal content is 1.0 ppm or less and the particle size is 0.5. 200 particles over m

A method of washing at least once a fluorine-containing rubber-based molded article with a liquid organic compound or an inorganic compound at a washing temperature not exceeding 1; a fluororubber-based molded article; It is a method of dry-etching and cleaning products; a method of extracting and cleaning fluororubber-based molded products; or a combination of these.

Significantly higher cleanliness can be achieved with the new cleaning method

However, from the viewpoint of semiconductor manufacturing, it is preferable that the degree of cleanliness be as high as possible. Therefore, the present inventors have found that the molding port from a variety of perspectives, including the manufacturing process of fluorine-based plastic molded articles.

We considered the cleanup of PP.

In the course of the above examination, the inventors of the present invention found that the mold agent used to release the mold from the molding die during the molding of fluorine elastomer was a gas. It has been discovered that it is one of the sources of contamination, such as the source of the source and the source of the particles.

In the molding of the mold of the ester, unlike the resin, when the molded PP is removed without involving a vulcanization reaction during molding and without cooling the mold. It was thought that the use of a mold release agent was indispensable for the reason that the strength when heated was low. Especially half In the case of parts for conductor manufacturing equipment, it is required that the surface of the molded part be smooth, and it is strongly desired that the part be released smoothly.

Examples of release agents for fluorine-based elastomers include silicone-based release agents, hydrocarbon-based surfactants, and the like. A fluorine-based surfactant and the like were used, and remained in the molded article even after the above-mentioned cleaning method was applied. Disclosure of the invention

In other words, the present invention relates to a fluorine-based molding method for forming a fluorine-based elastomer by using a molding die covered with a fluorine resin without using a release agent. Elastomer-A method of manufacturing molded articles. BEST MODE FOR CARRYING OUT THE INVENTION The manufacturing method of the present invention is carried out by using a molding die covered with fluororesin.

Fluororesin is non-adhesive, water- and oil-repellent, corrosion-resistant, heat-resistant, and has excellent mold release properties. The method of imparting mold releasability by adding a mold surface with a fluororesin is as follows: (1) After forming a hard surface layer of aluminum, the fluorine is added to the aluminum layer. (2) a method of forming a nickel surface layer by an electroless plating method, impregnating with a fluororesin, and then heat-treating. A method of forming a fluorine resin-containing nickel surface layer in a single step by mixing fluorocarbon resin in a nickel plating bath, chemical conversion treatment, and blast treatment on the mold surface And a method of forming a fluororesin layer after performing a primer treatment or the like. In the present invention, a mold manufactured by any method may be used, but from the viewpoint of durability and mold release, ③ Is preferred.

The fluororesin used for coating is polytetrafluoroethylene (PTFE) and tetrafluoroethylene, which are excellent in mold release, corrosion resistance and heat resistance. 1-fluoro (vinyl alcohol) copolymer (PFA), tetrafluoropropylene-hexafluoropropylene copolymer (FEP) Etc. are used.

As a molding method using such a fluororesin-coated molding die, an ordinary rubber (elastomer) molding method can be applied, for example, a compression molding method, an injection molding method, or the like. The molding method and the transfer molding method can be improved. The molding conditions are not particularly limited, and conventionally known conditions are employed.

The fluorine-based elastomer formed by the present invention is particularly limited as long as it is used for molding materials such as conventional materials and sealing materials. Without, for example,

Expression (1

-4 CH CF,

Two

CF

(Where m is 856, n is 15 to 40) or (2

4CF ₂ —

OR ,:

(Wherein, m is 95 to 50, n is 5 to 50, R _f is a perfluoroalkyl group having 1 to 8 carbon atoms, or oxygen having 3 to 12 carbon atoms. Fluoroalkyl containing 1 to 3 atoms

(Poly) ether group) represented by the following formula (3): -CH ₂ -CF ₂ ^-CF ₂ -CF ₂ ^ CF ₂ -CF ^

CF

Three

(Wherein, 1 is 85 to 20 and 111 is 0 to 40 n is 154), a terpolymer rubber represented by the formula:

Equation (4):

C

F H Y

Two

CF ₂ -CF + _n

C

F

2 XZ OR _f

1

(Wherein 1 is 95 to 45, m is 0 to; 10 and n is 5 to 45,

C I

X, Y and Z are each independently a fluorine atom or water

C I

An elementary atom, R _f is a pan-fluoroalkyl group having 1 to 8 carbon atoms) m

A terpolymer rubber represented by

Equation (5):

CF ₉ -CF ₉ — CF ₉ -CF + CF Ri CF-2-n

CF ORf

Three

(In the formula, 1 is 95 to 35, m is 0 to 30, n is 5 to 35, and R _f is a perfluoroalkyl group having 1 to 8 carbon atoms.) Terpolymer rubber, etc. Among these, from the viewpoint of chemical resistance, heat resistance, and plasma resistance, the binary copolymer rubber represented by the formula (1) or (2) is preferred. Alternatively, it is preferable to use a terpolymer rubber represented by the formula (3), and in order to provide a cured site, a monomer such as the following is used in an amount of 0 to 5 % Copolymerization may be used.

The monomers used in the copolymerization method include:

CF ₃

I

CF ₂ = CF (OCF ₂ CF O ~ -CF ₂ Χ '

(Where m is from 0 to 5, n is from! To 8), CF ₃ -CF--CF ₂ OCF CF ₂ OCF = CF ₂

I I

X ³ CF ₃

(n:! ~ 4),

CF ₂ = CFO (CF ₂ -OCF (CF ₃ ) X ^;

(n is 2-5),

(n:! ~ 6),

CF ₂ = CF [OCF ₂ CF (CF ₃ )] _n OCF ₂ CF (CF ₃ ) X ³

(n:! ~ 2), or

_{_{CF 2 = CFCF 2 0- - CFCF}} 2 0 -) ^ - CF- X 3

I I

CF ₃ CF ₃

[X ³ is CN, COOH or COOR ⁵ (R ⁵ is an alkyl group which may contain a fluorine atom having 10 carbon atoms)] and has a nitrile group-containing monomer represented by the formula: For example, a monomer having a hydroxyl group and a monomer having an alkoxycarbonyl group may be used.

In addition, copolymers of a copolymer that is an elastomeric segment and a copolymer that is a non-elastomer segment are also evident. It is.

An elastomeric segment refers to a segment that is amorphous and has a glass transition point of 25 ° C or lower, and is specifically preferred. For example, a monomer that provides a TFEZPAVEZ hardening site (45 to 90Z 10 to 500 to 5; mol%, the same applies hereinafter) may be used as the threshold composition. The preferred composition is 45 to 8 0 Z 2 0 to 5 0 5, especially 5 3 7 0 3 0 4

It is between 5/0 and 2.

As the monomer that gives the cured site, the monomer used in the above-mentioned copolymerization method is enumerated. For example, vinylidene fluoride, CX ₂ = CX - in R _f ³ CHRI (wherein, X is H, F or is CH _3, R _f ³ is full O b A Ruki les emission group, per full O port A Ruki les emission group, full O b An iodine-containing monomer represented by the following formula: a polyoxyalkylene group or a perfluoropolyalkylene group; R is H or CH 3);

(Wherein, m is 0 to 5, and n is 1 to 3), and bromine-containing monomers, and the like. Usually, iodine-containing monomers and the like are preferable.

In addition, as a copolymer that is a non-elastomer segment,

(1) VdFZTFE (0 to: 100Z100 to 0), especially VdF / TFΕ (70 to 99 930 to; L), PTFE or PVdF ;

(2) Echirenno TFEZHFP (6 to 430 to 810 to 30), 3, 3, 3 — Trifluoropropylene 1 2 — Trifluoromethylー 3, 3, 3 — Tri-fluoro mouth profile — 1 ZPAVE (40-60 / 60-

40);

_{(3) TFE / CF 2 =} CF - R f 1 ( non e la scan Bok Ma one of the indicating composition range, Chi I _{sand, CF 2 = CF - R f} 1 is 1 5 Mo less Le%);

(4) Vd FTFE / CTFE (50 ~ 99/30 ~ 0 2 0 1)

(5) V d F Z T F E H F P (6 0 9 9 3 0 0

1 0 1)

(6) Ethylene ZTFE (30 to 60 Z70 to 40);

(7) Polychloroethylene (PCTFE);

(8) Ethylene ZCTFE (30 to 60, Z 70 to 40), etc. can be obtained. This is al Chi jar of, chemical resistance and heat resistance point force, et al., PTFE your good in Japanese beauty TFEZCF ₂ = CF - barnyard La be sampled Ma one of the copolymer of R _f ¹ is to good or No.

The fluorine-based elastomer molded article obtained by the production method of the present invention does not contain a release agent. However, since it contains or adheres to contaminants other than mold release agents and foreign foreign substances (such as particles), it is desirable to carry out more rigorous cleaning. It is better. The washing method is as described above.

(1) No more than 300 fine particles (particles) with a metal content of less than 1.0 ppm and a particle size of more than 0.2 / m exceeding Zm1. Washing with ultrapure water several times,

(2) Washing temperature which does not contain more than 200 m1 of particles with a metal content of 1.0 ppm or less and a particle size of 0.5 / m or more. Washing at least once with an organic or inorganic compound in liquid form,

₍₃₎ UV / O 3 irradiation archery, Lee on-bi-over beam irradiation archery, Les chromatography The one beam irradiation method, dry What about was or-flops La Zuma irradiation method of gas-et-Tsu Chi in g method Cleaning method by etching method,

(4) Washing method by an extraction method such as the sock slide extraction method, high-temperature high-pressure extraction method, microwave extraction method, or supercritical extraction method

Etc. are exterminated. Needless to say, the washing method of (1), the washing method of (2), the washing method of (3) and the washing method of (4) can be used in any combination. it can .

In particular, the reduction in the number of particles in the molded article after washing, the reduction in the amount of ions, the reduction in the amount of gas generated, and the reduction in the amount of water generated, indicate that the H ₂ S 〇 ₄ and combining the mixed-solution by that cleaning in the cleaning and HF aqueous solution that by the the H ₂ 0 _2, is et to Chi for the I that boiling cleaning in ultrapure water line Tsu Na, inert gas flow down It is particularly preferred that the heat treatment be performed in a short time.

The fluorine-based elastomer molded article cleaned by the above method has 10,000 particles / cm ² having a particle size of 0.2 m or more on its surface. It is less than this, and it is more suitable for molded products such as sealing materials for manufacturing equipment in the semiconductor industry where the miniaturization is required and the cleanliness is required. It can be.

Specifically, the sealing materials include O-rings, corner rings, gaskets, knuckles, oil seals, and bearing seals. And lip seals. In addition, it can also be used as various elastomer products such as diaphragms, tubes, hoses, and various rubber rolls. It can also be used as a coating material and a lining material.

It should be noted that the semiconductor manufacturing apparatus according to the present invention is not limited to an apparatus for manufacturing semiconductors in particular, but is wide and widely used for liquid crystal panels and plasma panels. This includes all manufacturing equipment used in the semiconductor field where a high degree of cleanliness is required, such as equipment for manufacturing cells.

Specifically, it can be used by being incorporated in the following semiconductor manufacturing equipment. (1) Etching equipment

Dry cutting equipment

Plasma etching device Reactive ion etching device Reactive ion beam etching device Spatial etching device On-beam etching device

Jet-etching device

Fashioning

(2) Cleaning equipment

Dry etching cleaning equipment

UVZO ₃ cleaning equipment

Ion beam cleaning equipment

Laser beam Cleaning device Plasma cleaning device

Gas etching cleaning device Extraction cleaning device

Sock slide Extraction cleaning unit Temperature High-pressure extraction cleaning unit Water outlet Web extraction cleaning unit Critical extraction cleaning unit

(3) Exposure equipment

Stepper

One night in the evening

(4) Polishing device

C M P device

(5) Deposition equipment

CVD equipment Spanning ring device

(6) Diffusion / ion injection equipment

Oxidation diffusion device

Ion injection device

(7) Cleaning Using Hydrofluoric Acid, Hydrochloric Acid, Sulfuric Acid, Ozone Water, etc. The present invention will be described in detail using the embodiments below, but the present invention is not limited to this. It is not limited to them only.

Example 1

And a manual door La full O b e Chi-les-on _/ / path over full O (b) (A Le key Le bi two-le E one Te Le) both off Tsu-containing system a heavy case body e la be sampled Ma one For use, 100 g of the fluorine-based elastomer is used as a triarylsodium salt 2.0 g, 2, 5 — dimethyl 2, 5 — 0.5 g of hexane (t-butyl alcohol) was mixed, and the mixture was kneaded with a rubber mouth to prepare a rubber compound.

This rubber compound is formed into a mold without using a mold release agent by using a molding die, and then the O-ring (AS — 568 A-2) 14) was manufactured.

(Molding mold)

Dimensions: 20 X 20 cm (O-ring for 9 rings) Fluoro resin coating: Nickel layer coating with PTFE (thickness: 15 m)

( Molding condition)

Caro heat: 160 ° C x 10 minutes

Caro pressure: 200 kg f / cm "

The number of particles of this O-ring was adjusted by the following method, and as a result, it was 3.16 million cm ² .

(Number of particles) The sample was ultrasonically washed with ultrapure water at 25 ° C for 1 hour, and the number of particles having a particle diameter of 0.2 μm or more (particles) was measured using a fine particle measuring instrument (sensor sensor). Light is applied to the ultrapure water containing the particles that have flowed into the section, and the liquid is separated by a submerged particle counter (manufactured by Lion Corporation). A method of electrically measuring the amount of transmitted light and scattered light) and calculating by the following formula. Total amount of ultrapure water (ml)

O—Ring per ring

X

Number of particles from particle counter o-ring Sampling pure water volume (ml) (pcs)

Left

Number of particles =

(Pcs Z cm ² ) O-ring (AS-568A-214)

The surface area (cm ² ) per one piece of H 2 S / H ₂ O ₂ (1Z 1 double) is applied to this O-ring (AS-568A-214). The mixture was washed at 100 with the use of the mixed solution for 15 minutes, and then washed with a 50% aqueous HF solution at 25 for 15 minutes. Thereafter, the mixture is boiled at 100 ° C for 2 hours using ultrapure water, and is further subjected to a high-purity nitrogen gas flow of 20 m1 (volume 40 × 40 × 40 × 40). ) was heated at 180 ° C for 24 hours to remove water. The number of particles of the obtained final product was determined by the same method as described above, and as a result, the value was 0.1000 Zcm ² .

Comparative Example 1

In Example 1, a mold (material: steel material S50C) that was not coated with fluorocarbon resin was used as a molding mold, and a mold release agent (Diekin Co., Ltd.) was used. Die free ME810 (manufactured by Kogyo Co., Ltd.) applied at 0.2 g / m to the surface of the mold was similarly shaped and vulcanized, and the O-ring (AS— 5 6 8 A — 2 1 4) was manufactured. The number of particles in the O-ring for comparison was about 650,000 / cm ² , and the cleaning was performed in the same manner as in Example 1. At this time, the number of particles could only be reduced to 10,000 cm ² . Industrial applicability

According to the present invention, a mold release agent that can be a source of contamination and foreign matter can be excluded from a fluorine-based elastomer molded article, and a higher degree can be achieved. It is possible to provide a cleaned fluorine-based elastomer molded article.

Claims

Scope of demand

1. A fluorine-based elastomer that forms a fluorine-based elastomer using a molding die covered with a fluorine resin without using a release agent. Manufacturing method for molded products.

2. After the molding, is La, metal content 1. O ppm or less der Ri and particle size to zero. 5 2 0 0 The above fine particles m Z m 1-containing or not name and exceeded H ₂ S 0 ₄ and Chi was washed with a mixed aqueous solution of H ₂ 0 _2, the metal content of 1. O ppm is Ah Ri and particle size below 0. 5 m 2 0 0 pieces of fine particles on the following Z m After washing with an HF aqueous solution containing no more than 1, the fine particles having a metal content of 1.0 ppm or less and a particle size of 0.2 m or more exceed 300 particles Zm1. Wash with ultra-pure water, which contains no fine particles, and then contain 26 fine particles with a particle size of 0.2 m or more, not more than 26 liters, and the organic component content. The process for producing a molded article according to claim 1, wherein the water is removed in an inert gas or an air atmosphere having a (TOC) of 0.1 ppm or less.

3. The manufacturing method according to claim 1, wherein the molded article is a part for a semiconductor manufacturing apparatus.

4. The manufacturing method according to claim 1 or 2, wherein the molded article is a seal material for semiconductor manufacturing equipment.

5. A fluorine-based elastomer molded product that does not contain a release agent.

6. The molded PP according to claim 5, wherein the molded article is a part for semiconductor manufacturing equipment.

7. The molded article according to claim 5, wherein the molded article is a seal material for a semiconductor manufacturing apparatus.

8. Particles with a particle size of 0.2 m or more attached to the surface The molded article according to any one of claims 5 to 7, wherein the number of the molded articles is less than 10,000 Zcm ² .

9. Claims in which the number of particles with a particle size of 0.2 ^ m or more adhering to the surface is less than 500 / cm ² Any of claims 5 to 7 The molded article according to any one of the above.