JPH04180214A - Dummy wafer for aligner - Google Patents

Abstract

PURPOSE:To enhance a light-resistance property by a method wherein a photosensitive material whose optical property is changed with reference to light in a second wavelength band when it is irradiated with light in a first wavelength band, to which a write and erasure operation can be executed and which is composed of a spirooxadine-based photochromic material is formed on a substrate face. CONSTITUTION:A photosensitive material whose optical property is changed with reference to light in a second wavelength band when it is irradiated with light in a first wavelength band, to which a write and erasure operation can be executed and which is composed of a spirooxadine-based photochromic material is formed on the substrate face of a dummy wafer used for an aligner by means of which a pattern on a first object is exposed and transcribed onto a second object face by using the light in the first wavelength band. A material in which a spirooxadine-based photochromic compound has been monodispersed simply into a polymer or a material which contains a spirooxadine-based photochromic compound in a polymer by a covalent bond can be used for the spirooxadine-based photochromic material. Thereby, it is possible to obtain an excellent light-resistant property.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dummy wafer for an exposure apparatus used in the manufacture of semiconductor devices such as IC9LSI, and in particular to A dummy wafer for an exposure device for detecting illumination unevenness in a pattern area on an object surface when a pattern of a circuit or the like is exposed and transferred onto a second object surface such as a wafer surface directly or through an optical means such as a projection lens. It is related to.

[Prior Art] Continuously oscillating light sources such as ultra-high pressure mercury lamps have conventionally been used as illumination light sources in exposure apparatuses for manufacturing semiconductor devices such as ICs and LSIs. At this time, to measure the unevenness of illuminance on the irradiated surface, a light receiver consisting of a pinhole plate with an abbreviated number at the image plane position of the projection lens and a light receiving element placed behind it is moved within the irradiated surface in the direction of the image plane. This is done by detecting the amount of light at each position.

Japanese Unexamined Patent Publication No. 2-5403 discloses that instead of directly measuring the light intensity distribution on the irradiated surface with a light receiving element and converting it into an electrical signal, irradiation with exposure light in a first wavelength band is used to detect light in a second wavelength band. Using a dummy wafer on which a photosensitive material 9, for example, a photochromic material is provided on the substrate surface, the illumination distribution is stored on the surface of the dummy wafer, and the illuminance formed on the surface of the photosensitive material is measured. By measuring the distribution using light with a wavelength different from the wavelength of the illumination light, uneven illuminance on the irradiated surface can be measured quickly and with high precision, and is particularly suitable for semiconductor manufacturing equipment. Techniques regarding dummy wafers for devices are disclosed.

[Problems to be Solved by the Invention] However, although the photochromic materials used so far have good contrast and resolution, they have a problem of low light resistance and therefore a short number of repeated uses.

The present invention is intended to solve the problems of the prior art, and aims to provide a dummy wafer for exposure equipment that has excellent light resistance.

[Means for Solving the Problems] The present invention has the following configuration to achieve the above object.

"A dummy wafer for an exposure device that aligns a first object and a second object so that they face each other, and transfers the pattern on the first object surface onto the second object surface by exposure using light in a first wavelength band. A photosensitive material made of a spirooxazine-based photochromic material capable of writing and erasing whose optical properties change with respect to light in a second wavelength band when irradiated with light in a first wavelength band is provided on the surface of the substrate. A dummy wafer for exposure equipment characterized by It can be handled using the same method as described in .

The spirooxazine-based photochromic material used in the present invention is superior to spiropyran-based photochromic materials in terms of durability, coloring density, and especially light resistance, and is superior to spirooxazine-based compounds such as spirooxazine compounds and spiropyridoxazine compounds. is used.

The spirooxazine photochromic material used in the present invention may be one in which a spirooxazine photochromic compound is simply monodispersed in a polymer, or one in which a spirooxazine photochromic compound is contained in a polymer through a covalent bond. I can do it.

When simply monodispersing in a polymer, it is useful because a spirooxazine-based photochromic material can be easily produced. Polymers that can be used to disperse the spirooxazine photochromic compound in this case include styrene resins, acrylic resins, vinyl resins, polyester resins, urethane resins, epoxy resins, polyamide resins, and cellulose derivatives. Examples include, but are not limited to, the following.

These polymers may be used alone or in combination of two or more.

In addition, the method of incorporating spirooxazine-based photochromic compounds into polymers through covalent bonds allows for an increase in the amount of photochromic compounds added.
It is particularly suitable for increasing color density, preventing bleed-out of photochromic compounds from photochromic materials, and improving light resistance.

As a method for covalent bonding, a method using vinyl polymerization is advantageous in terms of the performance of the photochromic material and the manufacturing cost.

For vinyl polymerization, a spirooxazine compound provided with a polymerizable unsaturated functional group is preferably used. Such compounds include, but are not limited to,
-(meth)acryloxyethyl-3,3-dimethylindolinospironaphthoxazine, 1-(meth)acrylamidoethyl-3,3-dimethylindolinospirona.
phthoxazine, 1.3.3-)dimethyl-9'-(meth)acryloxyindolinospironaphthoxazine,
1.3.3-1 Limethyl-5'=(meth)acryloxymethylindolinospironaphthoxazine, 1.3.3
-trimethyl-9'-vinylbenzoyloxyindolinospironaphthoxazine and the like.

Furthermore, preferred examples of spirooxazine compounds having a polymerizable functional group include compounds represented by the following general formula.

(In the formula, the α ring is selected from a five-membered ring or six-membered ring containing one nitrogen atom, and a five-membered ring or six-membered ring containing one nitrogen atom connected to a benzene ring, a naphthalene ring, or a pyridine ring. The nitrogen atom in the α ring exists bonded to the organic group R1, and is represented by \N-R1.

/ Here, R1 is an alkyl group having 1 to 2 carbon atoms, or an alkyl group having 2 to 2 carbon atoms.
represents a substituent selected from an alkenyl group having 20 carbon atoms, an aralkyl group having 7 to 2 carbon atoms, and an aryl group having 6 to 2 carbon atoms.

R2 is an amino group having 0 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aralkoxy group having 7 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, or an acyloxy group having 2 to 20 carbon atoms; 1-20 alkyl group, carbon number 7-2
0 aralkyl group and an aryl group having 6 to 20 carbon atoms, and represents a substituent having at least one addition-polymerizable functional group.

R3 is hydrogen, an amino group having 0 to 20 carbon atoms, and 1 to 2 carbon atoms.
0 alkoxy group, aralkoxy group having 7 to 20 carbon atoms,
Aryloxy group having 6 to 20 carbon atoms, acyloxy group having 2 to 20 carbon atoms, alkyl group having 1 to 20 carbon atoms, 7 carbon atoms
represents a substituent selected from an aralkyl group having ~20 carbon atoms and an aryl group having 6 to 20 carbon atoms.

The β ring is a type selected from a hydrocarbon ring including an unsaturated aliphatic hydrocarbon ring having 4 to 10 carbon atoms, an aromatic hydrocarbon ring having 6 to 18 carbon atoms, and a heteroaromatic ring having 3 to 16 carbon atoms. be.

X represents O or S. ) In the spirooxazine compound represented by general formula (A), the α ring refers to a five- or six-membered ring containing one nitrogen atom, and a nitrogen atom connected to a benzene ring, naphthalene ring, or pyridine ring. It is one type selected from a five-membered ring or a six-membered ring containing one ring. Specific examples thereof include pyrrolidine ring, pyrrole ring, piperidine ring, tetrahydropyridine ring, dihydropyridine ring, indoline ring, henzindoline ring, tetrahydroquinoline ring, acridine ring, benzothiazoline ring, benzoxazoline ring, and pyridopyrrolidine ring. Can be mentioned.

The nitrogen atom contained in this α ring exists bonded to the organic group R1, that is, \ /N-R1F! 811 radical "Buddha 8" is an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 2 carbon atoms, and an alkenyl group having 7 to 2 carbon atoms.
represents a substituent selected from a 2o aralkyl group and an aryl group having 6 to 20 carbon atoms. Specific examples of R+ include chain alkyl groups such as methyl group, ethyl group, and octadecyl group, branched alkyl groups such as isopropyl group and 2-methylpentyl group, and cycloalkyl groups such as cyclohexyl group, norbornyl group, and adamantyl group. groups, alkenyl groups such as vinyl groups, allyl groups, isopropenyl groups, and 1,3-butadienyl groups, aralkyl groups such as benzyl groups, phenethyl groups, and (2-naphthyl)methyl groups, phenyl groups, 1-
Examples include aryl groups such as naphthyl groups.

When R1 is substituted, specific examples of the substituent include:
Hydroxy group; amino group, dibenzylamino group, (2-
Amino groups such as (methacryloxyethyl) amino groups; Alkoxy groups such as methoxy groups and tert-butoxy groups; aralkoxy groups such as benzyloxy groups and phenethyloxy groups; aryloxy groups such as phenoxy groups and 2-naphthyloxy groups; acetoxy groups and benzyloxy groups , acyloxy groups such as methacryloxy groups; carbamoyloxy groups such as N-phenylcarbamoyloxy groups and N-(2-methacryloxyethyl)carbamoyloxy groups; methyl groups,
Alkyl groups such as trifluoromethyl group and glycidyl group; Aralkyl groups such as benzyl group and phenethyl group; Aryl groups such as phenyl group and 1-naphthyl group; halogen groups such as chloro group and bromo group; diano group; carboxylic acid group, carboxyl group; Acid soda group, ethoxycarbonyl group, (2゜2.
Carboxylic acid groups such as 6.6-titramethylpiperidino)oxycarboxy groups; Nitro groups; Acyl groups such as acrylic and methacryl groups; Carbamoyl groups such as N-methylcarbamoyl groups; Sodium sulfonate groups, sulfonic acid groups Examples include sulfonic acid groups such as; sulfamoyl groups.

When the α ring is substituted, the substituents include R1
Preferable examples include the same substituents as those in .

Further, R2 is an amino group having 0 to 20 carbon atoms, or an amino group having 1 to 20 carbon atoms.
20 alkoxy groups, C7-20 aralkoxy groups, C6-20 aryloxy groups, C2-20 acyloxy groups, C1-20 alkyl groups, C7-20 aralkyl groups, and A substituent selected from aryl groups having 6 to 20 carbon atoms, such as hydrogen; amino group, piperidino group, 5. 6.
7゜Amino groups such as 8-tetrahydroisoquinolyl group, diethylamino group, (2-methacryloxyethyl)amino group; alkoxy groups such as methoxy group and tert-butoxy group; aralkoxy groups such as benzyloxy group and phenethyloxy group; Phenoxy group, aryloxy group such as 2-naphthyloxy group, acyloxy group such as acetoxy group, benzyloxy group, methacryloxy group; methyl group,
Alkyl group such as trifluoromethyl group; benzyl group,
Aralkyl groups such as phenethyl groups: include aryl groups such as phenyl groups and 1-naphthyl groups, and
It is necessary that these substituents contain at least one addition-polymerizable functional group.

Examples of the addition-polymerizable functional group contained in R2 include a radical-polymerizable functional group and a ring-opening polymerizable functional group. Specific examples include acrylic group, acryloxy group, acrylamide group, methacryloxy group, N-(
2-methacryloxyethyl)carbomoyloxy group,
p-vinylbenzyl group, 3.4-epoxybutyl group, 4
-acryloxypiperidino group, 4-methacryloxypiperidino group, 4.4-dimethacryloxypiperidino group, :3-[N-(2-methacryloxyethyl)carbamoyloxycopiperidino group, 2 -methacryloxymethylpiperidino group, 2-methacryloxyethyl group, 2-glycidyloxyethoxy group, 3-allyloxypiperidino group, 4-methacrylpiperazino group, 4- (
Examples include 2-methacryloxyethyl) piperazino group.

R3 is hydrogen, an amino group having 0 to 20 carbon atoms, and 1 to 2 carbon atoms.
0 aralkoxy group, an aralkoxy group having 7 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, and Represents a substituent selected from aryl groups having 6 to 20 carbon atoms.

On the other hand, the β ring is selected from a hydrocarbon ring including an unsaturated aliphatic hydrocarbon ring having 4 to 10 carbon atoms, an aromatic hydrocarbon ring having 6 to 18 carbon atoms, and a heteroaromatic ring having 3 to 16 carbon atoms. It is one of a kind. A hydrocarbon ring containing an unsaturated aliphatic hydrocarbon ring having 4 to 10 carbon atoms refers to an unsaturated aliphatic hydrocarbon ring having 4 to 10 carbon atoms, or an aromatic ring and an unsaturated aliphatic hydrocarbon ring connected to each other. and means a hydrocarbon ring having 4 to 10 carbon atoms.

Specific examples of the β ring include a cyclohexene ring, a cyclooctene ring, a cyclooctadiene ring, a cyclodecene ring, a norbornene ring, a bicyclo[2,2°2-cooctene ring, a dihydronaphthalene ring, a benzene ring, a naphthalene ring, an anthracene ring, Examples include a phenanthrene ring, a quinoline ring, a dibenzofuran ring, a dibenzonaphthothiophene ring, a benzofuran ring, an indole ring, a pyridine ring, and a pyrimidine ring.

Moreover, in general formula (A), X represents O or S.

Moreover, as a copolymerizable component with the photochromic compound having these polymerizable unsaturated functional groups, a monomer having a vinyl group is similarly preferable. Specific examples of such monomers include styrene, styrene derivatives, (meth)acrylic acid alkyl esters, (meth)acrylic acid hydroxyalkyl esters, (meth)acrylic acid, (meth)acrylamides, alkyl-substituted (meth)acrylamides, N
Examples include -substituted maleimide, maleic anhydride, (meth)acrylonitrile, methyl vinyl ketone, vinyl acetate, vinylidene chloride, divinylbenzene, ethyl alcohol di(meth)acrylate, and other polyfunctional (meth)acrylic acid ester compounds.

The content of the spirooxazine compound contained in such a photochromic material should be determined depending on the type of spirooxazine compound used, the characteristics of the designed exposure apparatus, etc., but is usually 0.5 w.
It is preferably used in a range of t% to 50v1%.

In the present invention, the spirooxazine-based photochromic material is provided by coating on the substrate. Solvents for photochromic materials used during coating include alcoholic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, normal butyl alcohol, isobutyl alcohol, tertiary butyl alcohol, methyl cellosolve, ethyl cellosolve, and isopropyl. cellosolve,
Glycol ether solvents such as butyl cellosolve and propylene glycol monomethyl ether, ester solvents such as ethyl acetate, butyl acetate and amyl acetate, aliphatic hydrocarbon solvents such as normal hexane, normal heptane and normal octane, cyclohexane and ethyl cyclohexane. Examples include alicyclic hydrocarbon solvents, petroleum solvents such as mineral spirits, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, and aromatic hydrocarbon solvents such as benzene, toluene, and xylene. These can be used alone or in combination.

Further, the solid content concentration in the solution used for coating the photochromic material varies depending on the applied coating method and coating conditions, and is preferably in the range of 5 wt% to 35 wt%.

Coating with this photochromic material can be done using commonly used methods such as dipping, spraying, roller coating, flow coating, offset printing, and screen printing, but it is also possible to obtain a thinner coating film with high precision. From this point of view, the spin code method is preferably used. The film thickness of such a photochromic material is determined by the type of photochromic compound used and the characteristics required of the exposure apparatus, but it is usually preferably used in the range of 0.5 μm to 10 μm. In particular, 1. from the viewpoint of contrast and machine operability.
0 μm to 5.0 μm is preferable.

In the present invention, the material used for the substrate of the dummy wafer may be the silicon wafer itself, but any material such as metal or glass may be used as long as it has good workability and has a coefficient of thermal expansion close to that of the silicon wafer. Available for use.

In addition, in the photochromic material according to the present invention, for the purpose of improving light resistance and coloring density, it is also preferable to add a light stabilizer, a sensitizer, etc. to the polymer solution used for coating the photochromic material.

[Example] The present invention will be described below with reference to Examples, but the present invention is not limited thereto.

Example 1 n-butyl methacrylate, methyl methacrylate, lauryl methacrylate, 1-benzyl-3,3-dimethyl-9'-methacryloxyspiro[indoline-2,3
--[3H] -naphtho[2°1-b] (1,4)
[Oxazine] were polymerized in toluene using azobisdimethylvaleronitrile as an initiator at a polymerization temperature of 70° C. for 10 hours under a nitrogen atmosphere.

The obtained spirooxazine photochromic compound copolymer solution was diluted with a diluted solution of ethyl acetate/butyl acetate/xylene = 1/1/1 (weight ratio) to a solid content concentration of 20.
After diluting to % by weight, the solution was filtered using a 1 μm membrane polytetrafluoroethylene filter to prepare a coating solution. This coating liquid was applied to a silicon wafer with a diameter of 15 cm using a spin code device.
After coating at a rate of 30 oorpm/min, a dummy wafer for an exposure apparatus having a coating having a thickness of 2 μm was prepared by drying.

The dummy wafer for exposure equipment obtained by the above method was
When irradiated with ultraviolet light of nm wavelength, it was colored blue with a maximum absorption wavelength of 600 nm. This colored dummy wafer is
When left in a dark place or heated, it returns to its initial colorless state.
It exhibited excellent durability, with the ability to repeat this coloring and decoloring process over 100 times.

Example 2 The copolymerization components described in Example 1 except for the photochromic monomer were polymerized in the same manner, and 1-benzyl-3,3-dimethylspiro[indoline-2,3- -[3H]-naphtho[2,1-b (
1,4) A coating polymer solution was prepared by adding 10 parts by weight of Oxazinco.

A coating solution was prepared in the same manner as in Example 1 using the solution of the spirooxazine-based photochromic compound and the acrylic copolymer obtained in this manner, and a dummy wafer for an exposure apparatus was produced using a spin cord.

The dummy wafer for exposure equipment obtained by the above method was
When irradiated with ultraviolet light of nm wavelength, it was colored blue with a maximum absorption wavelength of 600 nm. This colored dummy wafer is
When left in a dark place or heated, it returns to its initial colorless state.
It exhibited excellent durability, with the ability to repeat this coloring and decoloring process over 100 times.

Comparative Example 1 A coating liquid was prepared in the same manner as described in Example 1 using a mixture of 15 parts by weight of a spiropyran compound and 85 parts by weight of polymethyl methacrylate, and a dummy wafer for an exposure apparatus was produced using a spin cord.

The dummy wafer for exposure equipment obtained by this method has 360
It was colored in a deep color by irradiating it with nanometer ultraviolet rays, and the coloring and decoloring were repeated in the same manner as in the examples, but the durability of this repetition was low, being only a few times.

[Effects of the Invention] As described above, a dummy wafer provided with a photosensitive material whose optical properties (transmittance) change with respect to light in a second wavelength band by irradiation in a first wavelength band is used, exposing to light to form an illuminance distribution and storing information regarding the illuminance distribution;
In the method of removing the dummy wafer from the stage and measuring the transmittance distribution, the dummy wafer for exposure equipment obtained using the spirooxazine-based photochromic material of the present invention has useful performance in practical terms and excellent light resistance. Met.

Claims (2)

[Claims] (1) An exposure device for aligning a first object and a second object so that they face each other, and transferring the pattern on the first object surface onto the second object surface by exposure using light in a first wavelength band. A dummy wafer, which is a photosensitive material made of a spirooxazine-based photochromic material that can be written and erased, and whose optical properties change with respect to light in a second wavelength band when the substrate surface is irradiated with light in a first wavelength band. A dummy wafer for exposure equipment, characterized in that it has: (2) The dummy wafer for an exposure apparatus according to claim (1), wherein the spirooxazine-based photochromic material is contained in the polymer through a covalent bond.