JP2000187337A - Developer and developing method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain excellent wettability to a photoresist, to uniformly spread a developer, to suppress the rate of dissolution in a low exposed part and to form a micro pattern with excellent reproducibility by developing with a developer containing a specific compound in a prescribed concentration succeeding to the exposure using an excimer laser beam. SOLUTION: The photoresist exposed with the excimer laser beam, containing no organic basic compound and having environmental stability is developed with the developer containing the compound expressed by a formula in the concentration of 1-5000 wt.ppm. In the formula, R represents a 3-20C hydrocarbon; each of (n) and (m) represents the integers satisfying n+m=3 to 100. The light source of the excimer laser beam is at least one kind selected from KrF excimer laser, ArF excimer laser and F2 excimer laser. The developer is an aq. solution containing a nonmetal alkali compound. The photoresist is a positive chemically amplified photoresist and exhibits the environmental stability by baking at a high temp.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing solution and a developing method for a photoresist used in photolithography, and more particularly, to an application for developing a photoresist for an excimer laser used for forming a fine pattern in an VLSI manufacturing process. It is suitable.

[0002]

2. Description of the Related Art In recent years, in the manufacture of semiconductor devices,
2. Description of the Related Art Higher density and finer semiconductor integrated circuits are being promoted. Along with this, in the lithography process for forming a pattern, a shorter wavelength Kr, which is shorter than i-line (365 nm) using a conventional mercury lamp as a light source of an exposure apparatus, is used.
It is shifting to an F excimer laser (248 nm) and an ArF excimer laser (193 nm).

With the shift of the light source used, in the case of i-line, as a photoresist composition, a composition obtained by combining a naphthoquinonediazide compound as a photolytic agent with a novolak resin soluble in a developer is used. Was used,
In the case of an excimer laser, a photoresist composition is a resin in which the solubility in a developing solution is suppressed by masking a functional group in a base resin which is soluble in the developing solution with a protecting group, and an acid by light reception (exposure). And a photo-acid generator that generates chromium are mainly used. Such a photoresist is called a chemically amplified photoresist.

In a photoresist for an excimer laser, particularly a chemically amplified positive photoresist, an acid is generated from a photoacid generator by exposing a photoresist coated on a substrate such as a silicon wafer with an excimer laser beam. Occurs and a reaction occurs in which the acid cleaves the protecting group by baking after exposure. As a result, the base resin of the photoresist becomes soluble in the developing solution, and the photoresist is developed.

[0005] However, in this photoresist, the photoacid generator is inactivated by infiltration of impurities in the atmosphere, particularly, a base component or the photoresist, whereby the photoresist is inactivated.
As a result, there has been a problem that it is difficult to dissolve in a developer and a desired pattern cannot be obtained. In particular, it is known that the interval greatly affects the baking before and after the exposure. There is a method for solving this problem from the viewpoint of process and material.

For example, a method of removing impurities from a process atmosphere, a method of coating a protective film for preventing the intrusion of impurities into the surface of a resist, a method of adding a basic compound or the like to a photoresist, and a method of keeping a photoresist at or above its glass transition temperature. A method of baking at a high temperature (annealing method) is exemplified.

In this annealing method, the free volume in the photoresist is reduced by baking at a temperature higher than the glass transition temperature of the base resin of the photoresist during the application of the photoresist, so that impurities in the atmosphere are reduced. It is to make it hard to spread inside. However, in a conventional photoresist material, when baking is performed at a temperature higher than the glass transition temperature, a protective group is eliminated or a photoacid generator is decomposed. Accordingly, base resins, photoacid generators, and the like that are stable at high temperatures have been developed. For example, a copolymer containing acrylic acid and methacrylic acid protected with a t-butyl group, a t-butoxy group and the like, a derivative thereof, and hydroxystyrene and a derivative thereof (the copolymer in the present invention is a two-component or By using the above multi-component terpolymer and quaternary copolymer) as the base resin, a photoresist that can be baked at a high temperature can be obtained.

As a developing solution for such a photoresist, an aqueous solution of an alkaline compound is generally used. In the manufacture of a semiconductor device, the use of an alkali compound containing a metal ion may adversely affect the device characteristics. Therefore, a non-metal alkali compound containing no metal ion, for example, tetramethylammonium hydroxide (hereinafter, referred to as tetramethylammonium hydroxide) , TMAH) or an aqueous solution of trimethyl (2-hydroxyethyl) ammonium hydroxide (choline).

As a property required for a developing solution of a photoresist, a high resolution is required. That is, it is required that the ratio of the developing speed between the exposed part and the non-exposed part of the photoresist, that is, the selectivity of the photoresist to the developing solution is high, which is important for obtaining a fine photoresist pattern.

As described above, since the developer is an aqueous solution, the developer has insufficient wettability with respect to the hydrophobic resist surface. Therefore, the developing solution does not spread evenly over the entire surface of the photoresist on the substrate, and as a result, the pattern shape varies depending on the position on the substrate surface, and does not sufficiently penetrate to the base of the fine pattern, which causes poor development. There was a case.

As a developing method in a manufacturing process of a semiconductor integrated circuit, a paddle developing method is frequently used, and in this method, wettability of a developing solution is particularly important. In addition, silicon wafers used in the manufacture of semiconductor devices have been increasing in diameter, and there has been a desire for a developer having even better wettability.

As a method for solving the above-mentioned problems, a technique for improving the wettability by adding a surfactant to a developer is described in JP-A-5-303208. Further, JP-A-5-303209 and the like disclose development with a developer to which a surfactant is added, and the so-called QUA
EST (QUadrupole Efect for Stepper Technology)
And 0.2 using a KrF excimer laser.
A method for forming a μm pattern is described.

[0013]

However, the conventional method as described above has a problem that it is extremely difficult to obtain a good photoresist pattern smaller than 0.2 μm with good reproducibility. For example, when a positive photoresist is used, the dissolution rate of the resist in a substantially unexposed portion, that is, in a low-exposed portion is increased by the action of a surfactant, and as a result, the substantially exposed high-exposed portion is exposed. The selectivity (resolution) between the exposed part and the low-exposed part is reduced, which prevents formation of a fine photoresist pattern having a desired shape.

Therefore, the present invention is excellent in leaking property to a photoresist, and can not only spread the developing solution uniformly on the photoresist surface, but also further suppress the dissolution rate of the photoresist in a low exposure part (low dissolution part). It is an object of the present invention to provide a developing solution and a developing method capable of forming a fine pattern with good reproducibility.

[0015]

The developing method of the present invention has a general formula:

[0016]

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(Wherein R is a hydrocarbon having 3 to 20 carbon atoms, and n and m are integers satisfying n + m = 3 to 100). Using a developing solution having a concentration within the range, a photoresist which does not contain an organic basic compound and has environmental stability and is exposed to light by excimer laser light is developed.

In one embodiment of the developing method of the present invention, the light source of the excimer laser light is a KrF excimer laser,
At least one selected from rF excimer laser and F ₂ excimer laser.

In one embodiment of the developing method of the present invention, the developer is an aqueous solution containing a non-metallic alkali compound.

In one embodiment of the developing method of the present invention, the photoresist is a chemically amplified positive photoresist.

In one embodiment of the developing method of the present invention, the photoresist exhibits environmental stability by being baked at a high temperature.

In one embodiment of the developing method of the present invention, the photoresist comprises a resin having a solubility in the developing solution suppressed by masking a functional group of a compound soluble in the developing solution with a protecting group; A photo-acid generator that generates an acid that generates a reaction that cleaves the protective group by receiving light.

In one embodiment of the developing method of the present invention, the photoresist contains at least hydroxystyrene or a derivative thereof and acrylic acid or a derivative thereof in monomers constituting the base resin.

In one embodiment of the developing method of the present invention, the developing speed is 0.050 nm / sec to 0.100 nm / sec.

In one embodiment of the developing method of the present invention, a KrF excimer laser is used as the light source, and a square or circular hole having a side or a diameter of 0.14 μm or less is formed in the photoresist.

The developing solution of the present invention is used for developing a photoresist which does not contain an organic basic compound exposed to excimer laser light and has environmental stability.

[0027]

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(Wherein R is a hydrocarbon having 3 to 20 carbon atoms, and n and m are integers satisfying n + m = 3 to 100). Include in concentrations within the range.

[0029]

In the developing method of the present invention, subsequent to exposure using excimer laser light, development using a developing solution containing a compound of the above general formula at a predetermined concentration is performed. An excimer laser has a strong oscillation line in an ultraviolet region or a vacuum ultraviolet region, and enables exposure of an extremely fine structure of a photoresist, for example, about 0.1 nm. A developer containing a compound at a concentration allows such a fine structure to be revealed in detail.
That is, even when a latent image pattern having an extremely fine structure is exposed to light with an excimer laser beam having a short wavelength, a fine visual pattern corresponding to the latent image pattern can be formed by the developer.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred developing method using a photoresist developer according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a flowchart showing the photoresist developing method according to the present embodiment in the order of steps.

First, in step S1, a photoresist is applied to the surface of a substrate such as a silicon wafer. As a coating method, a method using a spin coater, a method using a roll coater, or the like is suitably used. Further, a processing agent represented by hexamethyldisilazane (hereinafter abbreviated as HMDS) is applied as necessary. Thereafter, a photoresist may be applied. The anti-reflection film is HMDS
Alternatively, it may be formed after applying a resist.

In step S2, a first bake (pre-bake before exposure) is performed on the photoresist applied on the substrate as necessary. For example, the temperature of the first bake is 80 ° C. to 150 ° C., and the time is about 90 seconds to 120 seconds.

[0033] In step S3, the substrate was placed a layer of photoresist is formed in the exposure apparatus to expose a layer of photoresist KrF excimer laser, ArF excimer laser, the F ₂ excimer laser, or the like. When a stepper device or scanner device is used as a normal exposure device,
An image corresponding to the reticle is printed as a latent image on the photoresist layer.

In step S4, a second bake (pre-bake after exposure) is performed as necessary. For example, the temperature of the second bake is 100 ° C. to 150 ° C., and the time is 90 ° C.
About 120 seconds.

In step S5, the photoresist on which the latent image has been formed is developed using a developing solution described later. When a positive photoresist is used as in the present embodiment, the exposed portion reacts with the developing solution and elutes into the developing solution.

Thereafter, washing and post-baking are performed as necessary. After the photoresist pattern is formed, when the photoresist pattern is used to pattern electrodes and wiring, to pattern contact holes and through holes, and to form a groove for performing a damascene method or a dual damascene method. Is performed using a photoresist pattern as an etching mask. Alternatively, in the case of forming or doping a diffusion layer, ions are implanted into a desired region exposed from the photoresist pattern using the photoresist pattern as an ion blocking mask. In this way, various processes are performed on the substrate.

An alkaline aqueous solution is used as one component in the developing solution that can be used in the present embodiment. The alkaline aqueous solution is a main component of the developer in terms of weight ratio, and known aqueous solutions can be used without any limitation. Specifically, primary, secondary, tertiary amines, for example, propylamine, butylamine, dibutylamine, aqueous solutions of amines such as triethylamine,
Cyclic bases containing at least one selected from carbon, nitrogen, oxygen and sulfur atoms, such as pyrrole, pyrrolidine, pyrrolidone, pyridine, morpholine, pyrazine, piperidine, oxazole, thiazole and the like.

Further, a quaternary ammonium base or the like can be used. Specifically, TMAH, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, trimethylethylammonium hydroxide,
Trimethyl (2-hydroxyethyl) ammonium hydroxide, triethyl (2-hydroxyethyl) ammonium hydroxide, tripropyl (2-hydroxyethyl) ammonium hydroxide, trimethyl (1-hydroxypropyl) ammonium hydroxide and the like, Among these, TMAH, trimethyl (2
(-Hydroxyethyl) ammonium hydroxide can be used particularly preferably. Further, two or more kinds of the developer may be combined.

As the concentration of the alkali, an appropriate concentration is selected depending on the alkali used, but it is generally used in the range of 0.1% by weight to 10% by weight, preferably 1% by weight to 5% by weight. If the concentration is lower than the lower limit of this range, a portion to be eluted (exposed portion in the case of a positive type) is not sufficiently eluted in the developer, and a pattern (visible image) is not formed. Also,
If it exceeds the upper limit of this range, it will dissolve in the developing solution up to an inconvenient part (low-exposure part in the case of a positive type) if eluted,
It becomes difficult to form a good pattern. Therefore, a desired pattern can be formed satisfactorily by setting the concentration within the above range.

In this embodiment, particularly, in the above-mentioned alkaline aqueous solution,

[0041]

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At least one of the compounds represented by the formula (1) is added.

In the above formula, R is a hydrocarbon group having a saturated or unsaturated bond and acting as a hydrophobic group, and may be any of linear, branched and cyclic. More preferably, it is a hydrocarbon having 3 to 20 carbon atoms. If the number of carbon atoms is less than 3, the leakage of the developer to the resist will not be sufficient. On the other hand, when the carbon number is larger than 20,
Similarly, in addition to insufficient leakage, foaming also increases. Further, it is preferable to use a hydrocarbon group in which the hydrogen is not replaced by fluorine or the like.

The hydrophilic group is a polymer of ethylene oxide or propylene oxide, or a copolymer of ethylene oxide and propylene oxide;
m is 0 or a positive integer, and those satisfying n + m = 3 to 100 are preferably used. When the value of n + m is less than 3, the compound represented by the general formula becomes difficult to dissolve in the developer, and when it exceeds 100, the wettability becomes insufficient.

The above compound functions as a nonionic surfactant and has a concentration of 1 ppm by weight to 5000 ppm.
Weight ppm, and combined with a positive photoresist for an excimer laser having environmental stability, as described below, a fine and good shape such as cannot be obtained with other surfactant-added developers. A pattern is obtained.

Among the compounds represented by the above general formulas, those preferably used are specifically described as follows: polyoxyethylene propyl phenyl ether, polyoxyethylene isopropyl phenyl ether, polyoxyethylene pentyl phenyl ether, polyoxyethylene pentyl phenyl ether, Oxyethylene cyclopentyl phenyl ether, polyoxyethylene hexyl phenyl ether, polyoxyethylene cyclohexyl phenyl ether, polyoxyetherenepentyl phenyl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene dodecyl phenyl ether, Polyoxyethylene tridecyl phenyl ester, polyoxypropylene propyl phenyl ether, polyoxypropylene isopropyl Phenyl ether, polyoxypropylene pentyl phenyl ether, polyoxypropylene cyclopentyl phenyl ether, polyoxypropylene hexyl phenyl ether, polyoxypropylene cyclohexyl phenyl ether, polyoxypropylene pentyl phenyl ether, polyoxypropylene octyl phenyl ether, polyoxypropylene nonyl phenyl Ether, polyoxypropylene dodecyl phenyl ether, polyoxypropylene tridecyl phenyl ether, polyoxyethylene propylene propyl phenyl ether, polyoxyethylene propylene isopropyl phenyl ether, polyoxyethylene propylene penter phenyl ether, polyoxyethylene propylene cyclopentyl phenyl ether , Polyoxyethylene propylene hexyl phenyl ether, polyoxyethylene propylene cyclohexyl phenyl ether, polyoxyethylene propylene pentyl phenyl ether, polyoxyethylene propylene octyl phenyl ether, polyoxyethylene propylene nonyl phenyl ether, polyoxyethylene propylene dodecyl phenyl ether, And polyoxyethylene propylene tridecyl phenyl ether.

As described above, in the present embodiment, the concentration of the compound represented by the general formula is 1 to the developing solution.
It is from ppm to 5000 ppm by weight, preferably from 5 ppm to 1000 ppm by weight. If the concentration of the compound represented by the above general formula is lower than 1 ppm by weight, the leakage to the photoresist becomes insufficient. On the other hand, if it is higher than 5,000 ppm by weight, foaming becomes large, and the bubbles adhere to the photoresist surface, which tends to cause poor development.

The positive photoresist having environmental stability used in this embodiment includes i-line, KrF, and A-line.
Any material having sensitivity to rF, F ₂ excimer laser light, or light in the ultraviolet or vacuum ultraviolet region of 350 nm or less including these wavelengths can be used. In particular, a photoresist in which the base resin of the photoresist is a resin in which a protective group is introduced into a resin soluble in a developer, and which exhibits environmental stability by baking at a high temperature equal to or higher than the glass transition temperature is preferable. is there.

When a KrF excimer laser is used as an exposure light source, it is more preferable to use a copolymer containing acrylic acid and its derivatives, hydroxystyrene and its derivatives protected with a t-butyl group or a t-butoxy group. Positive photoresist as the base resin is preferred.

Examples of the protecting group include a t-butyl group, a t-butoxy group, a tetrahydropyranyl ether group, a trimethylsilyl ether group, and an isopropyloxy group.

Examples of the photoacid generator include triphenylsulfonium hexafluoroantimonate, halogenated isocyanurate, halogenated triazine, nitrobenzyl sulfonate, diazonaphthoquinone-4-sulfonate, and alkyl sulfonate. , Bisarylsulfonyldiazomethane, β
N-sulfonyloxynaphthalimide derivatives such as -oxocyclohexylmethyl (2-norbornyl) sulfonium trifluoromethanesulfonate, cyclohexylmethyl (2-oxocyclohexyl) sulfonium trifluoromethanesulfonate, N-campforsulfonyloxynaphthalimide And the like.

When a non-chemically amplified positive photoresist for i-line is developed using the developing solution used in the present embodiment, the phenomenon that the non-exposed portion is eluted hardly occurs. . Therefore, even if the above-described phenyl ether-based compound is used as a surfactant, the resulting photoresist pattern is different from a photoresist pattern developed by a developer containing another compound as a surfactant. There is no clear difference in comparison.

The developing solution used in the present invention may contain known additives used in conventional developing solutions as long as the object of the present invention is not impaired. For example, surfactants, wetting agents, stabilizers, and dissolution aids other than the above compounds are used. These are added alone or in combination of two or more.

The presence of the above-mentioned compound in the developer can be detected by separating the compound using liquid chromatography and measuring mass spectrometry or infrared absorption spectrum.

As a method of bringing a developing solution into contact with a photoresist to cause a reaction, a substrate such as a silicon wafer on which a photoresist layer is formed is immersed in the developing solution for a certain period of time and then immersed in pure water. Immersion development method to dry,
A puddle developing method in which the developing solution is dropped on a photoresist surface, allowed to stand for a certain period of time, washed with pure water and dried,
After spraying the developer on the photoresist surface,
It is appropriately selected and used from a spray developing method of washing with pure water and drying.

As described above, by developing the photoresist using the developing solution of this embodiment, a KrF excimer laser can be used to form a gate electrode having a line width of about 0.14 μm or to reduce the diameter or one side of the gate electrode to about 0.14 μm. Holes of about .14 μm can be formed satisfactorily. In addition, with an ArF excimer laser, a gate electrode having a line width of about 0.11 μm and a hole having a diameter or one side of about 0.11 μm can be favorably formed. Further, if an F ₂ excimer laser is used, a gate electrode having a line width of about 0.09 μm and a hole having a diameter or one side of about 0.09 μm can be favorably formed.

[0057]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and some Comparative Examples. Needless to say, the present invention is not limited to these embodiments.

Example: 2.38% by weight as a developing solution
TMAH aqueous solution (trade name SD- manufactured by Tokuyama Corporation)
1) was prepared by adding a nonionic surfactant comprising a compound having an ester bond as shown in FIG.

First, sulfuric acid-hydrogen peroxide (volume ratio 4:
A silicon wafer whose surface was cleaned in 1) was prepared and baked on a hot plate at 200 ° C. for 60 seconds.
After baking, hexamethyldisilazane (HMDS) was applied, the surface of the wafer was subjected to a hydrophobic treatment, and an antireflection film was further applied and formed. Then, a chemically amplified positive photoresist (UV6 manufactured by Shipley Far East Co., Ltd.) for KrF excimer laser was applied to this silicon wafer by a spinner coater, and then prebaked at 135 ° C. for 90 seconds. The thickness of the photoresist film after pre-baking is 4
It was about 00 nm.

For exposure, a KrF excimer laser reduction projection type exposure apparatus (FPA-300 manufactured by Canon Inc.)
0EX4) was used. 0.14μm diameter for cross-section observation
Using a reticle having a contact hole pattern for forming a small number of holes, a large number of hole patterns were printed on the photoresist film at an exposure amount of 1000 to 2500 J / m ² .

Similarly, a silicon wafer having the photoresist film formed thereon was prepared, and a 10 mm × 10 mm square pattern was baked as a contact angle measuring pattern without a reticle at an exposure dose of 300 J / m ² . Immediately after the exposure treatment, a post-exposure bake at 135 ° C. for 90 seconds was performed.

Seven kinds of samples in which such contact hole patterns were baked were prepared, and as described above, in five kinds of developing solutions to which the compounds of Samples 1 to 7 shown in FIG. Development was carried out at 1 ° C. for 1 minute by an immersion method. Thereafter, the wafer was rinsed in pure water, and the wafer was dried together with the obtained photoresist pattern.

The contact hole pattern of the obtained photoresist was observed with an SEM (scanning electron microscope) photograph, and the contact hole pattern shape was evaluated. The evaluation criteria are as follows. That is, in FIG.
This shows that a resist pattern having a diameter of 4 μm was obtained with good shape. That is, as shown in FIG. 3, the upper portion of the resist pattern 12 on the silicon wafer 11 was relatively flat, and a contact hole pattern 13 having a substantially uniform hole diameter was obtained as a whole.

The development of the chemically amplified resist is schematically shown with reference to FIG. That is, in this case, in the photoresist to be used, the functional group (protective group) which is hardly soluble in the developing solution is cut by the light irradiation treatment and the heat treatment, and the resin is easily dissolved in the developing solution having a hydroxyl group.

In each of the samples shown in FIG. 2, the developing speed was calculated by measuring the film thickness of the non-exposed portion at a liquid temperature of 23 ° C. at regular intervals.

Here, several comparative examples with respect to the embodiment according to the present invention will be described.

(Comparative Example 1) First, Comparative Example 1 will be described. As a developing solution, a developing solution composed of a TMAH aqueous solution without an additive (corresponding to sample 1) as shown in FIG.
Was adjusted and prepared. Otherwise, the photoresist pattern was formed in the same manner as in the example.

As a result, the photoresist of Sample 1 developed with the developing solution to which the surfactant was not added had a good pattern as shown in FIG. 3, but a partially defective pattern as shown in FIG. Was also seen. The developing speed, that is, the speed at which the non-exposed portions began to dissolve in the developer was low.

The resist pattern 14 developed with a developer containing a surfactant other than the present invention has a rounded upper portion as shown in FIG. 6, and the diameter of the contact hole pattern 15 is smaller than 0.14 μm. Was also big. In FIG. 5, those corresponding to this are indicated by x marks. The developing speed, that is, the speed at which the non-exposed portions dissolved into the developing solution, was higher than that of the example, and the resolution was poor.

(Comparative Example 2) DP-052AC (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) was used as a photoresist, and a contact angle measuring pattern was 1 without a reticle.
A square pattern of 0 mm × 10 mm was exposed at a dose of 100 J /
except that it was baked in cm ² ,
A photoresist pattern was formed. FIG. 7 as a developer
The TMAH aqueous solution without additives (corresponding to sample 1) and five types of surfactant-containing developing solutions (corresponding to samples 2-6) were used as shown in FIG.

As a result, the photoresist of Sample 1 developed with the developing solution to which no surfactant was added had a good pattern as shown in FIG. 3, but a partially defective pattern as shown in FIG. Was also seen. The developing speed, that is, the speed at which the non-exposed portions began to dissolve in the developer was low. As shown in FIG. 6, a resist pattern 14 obtained by developing a photoresist other than the present invention had a rounded upper portion, and thus a contact hole pattern 15 was formed in which the hole diameter was considered to be irregular. This is indicated by a cross in FIG.

As described above, according to the embodiment of the present invention, particularly, the developing speed is 0.050 nm / sec to 0.100 nm / sec.
A good resist pattern was obtained with a thickness of nm / sec.

[0073]

According to the present invention, not only is the wettability to the photoresist excellent, the developer is uniformly spread on the photoresist surface, but also the dissolution rate in the low-exposure portion (low-dissolution portion) of the photoresist is further improved. Thus, a fine pattern can be formed with good reproducibility, and for example, a good photoresist pattern having a hole diameter and width of less than 0.2 μm can be obtained with good reproducibility.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating a method for developing a photoresist for an excimer laser according to an embodiment of the present invention.

FIG. 2 is a diagram showing evaluation results according to an example of the present invention.

FIG. 3 is a schematic sectional view showing a pattern of a photoresist obtained according to an embodiment of the present invention.

FIG. 4 is a schematic view showing a state of developing a photoresist according to one embodiment of the present invention.

FIG. 5 is a diagram showing evaluation results with respect to Comparative Example 1;

FIG. 6 is a schematic cross-sectional view showing a pattern of a photoresist obtained according to Comparative Example 1.

FIG. 7 is a diagram showing evaluation results of Comparative Example 2 for the present invention.

[Description of Signs] 11 Silicon wafer 12, 14 Resist pattern 13, 15 Contact hole pattern

Continued on the front page (72) Inventor Tadahiro Omi, 1-17-1, Yonegabukuro, Aoba-ku, Sendai-shi, Miyagi 301 (72) Inventor Yukio Tamai 12-12 Matsugaoka, Matsugaoka, Taishiro-ku, Sendai-shi, Miyagi Room 26, Matsugaoka Heights (72) Inventor Satoshi Kawada 1-1, Mikage-cho, Tokuyama-shi, Yamaguchi Pref. Tokuyama Co., Ltd. (72) Inventor Yoshihiro Shiode 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term (reference) 2H025 AA02 AA03 AA04 AB16 AC01 AC08 AD03 BE00 BE10 CB13 CB14 CB17 CB41 FA12 FA15 FA16 FA17 2H096 AA25 BA11 EA05 FA01 GA09 GA11 5F046 CA04 LA00 LA19

Claims (10)

[Claims] (1) A compound represented by the general formula: (Wherein, R is a hydrocarbon having 3 to 20 carbon atoms, n, m
Is an integer satisfying n + m = 3 to 100. Using a developing solution containing the compound represented by the formula (1) in a concentration within the range of 1 ppm by weight to 5000 ppm by weight, developing a photoresist having no environmental stability and exposing an organic basic compound exposed to excimer laser light. A developing method. 2. A light source for the excimer laser light, the light source comprising KrF
Developing method according to claim 1, wherein the excimer laser is at least one selected from ArF excimer laser and F ₂ excimer laser. 3. The developing method according to claim 1, wherein the developing solution is an aqueous solution containing a non-metallic alkali compound. 4. The photoresist according to claim 1, wherein the photoresist is a chemically amplified positive photoresist.
4. The developing method according to any one of 3. 5. The developing method according to claim 1, wherein said photoresist exhibits environmental stability by being baked at a high temperature. 6. The photoresist, wherein the functional group of the compound soluble in the developing solution is masked with a protecting group to suppress the solubility in the developing solution, and the protecting group is formed by receiving the excimer laser light. The developing method according to any one of claims 1 to 5, further comprising a photoacid generator that generates an acid that causes a cleavage reaction. 7. The photoresist according to claim 1, wherein a monomer constituting the base resin contains at least hydroxystyrene or a derivative thereof and acrylic acid or a derivative thereof. Item 2. The developing method according to Item 1. 8. A developing speed of 0.050 nm / sec to 0.1.
The developing method according to any one of claims 1 to 7, wherein the development speed is 00 nm / sec. 9. A KrF excimer laser is used as the light source, and the photoresist has a side or a diameter of 0.14 μm.
The developing method according to any one of claims 2 to 8, wherein a square or circular hole of m or less is formed. 10. A developer used for developing a photoresist which does not contain an organic basic compound exposed to excimer laser light and has environmental stability, wherein the developer has a general formula: (Wherein, R is a hydrocarbon having 3 to 20 carbon atoms, n, m
Is an integer satisfying n + m = 3 to 100. A developer comprising the compound represented by the formula (1) in a concentration within the range of 1 ppm by weight to 5000 ppm by weight.