KR20070106212A - Composition for preventing mixture of interface between hard mask film and photoresist film and manufacturing method of semiconductor device using the same - Google Patents

Abstract

A composition for preventing intermixing on the interface between a hard mask film and a photoresist film is provided to inhibit footing on the lower part of a photoresist pattern, thereby transferring a vertical uniform pattern form to the underlying layer. A composition for preventing intermixing on the interface between a hard mask film and a photoresist film comprises: (i) a compound represented by the following formula 1; and (ii) an organic solvent. In formula 1, R is a C1-C10 substituted or non-substituted alkylene, and each of n and m represents an integer of 10-20. The organic solvent is used in an amount of 2,000-10,000 parts by weight per 100 parts by weight of the compound represented by formula 1.

Description

Composition for Preventing Mixture of Interface between Hard mask Film and Photoresist Film and Manufacturing Method of Semiconductor Device Using the Same}

1 is a schematic view of a process drawing showing a method for manufacturing a semiconductor device including a conventional multilayer hard mask film.

2 is a schematic diagram of a process drawing showing a method of manufacturing a semiconductor device including a multifunctional hard mask film.

3A to 3D are cross-sectional views illustrating a method of manufacturing a semiconductor device including the anti-mixing film according to the present invention.

4 is a photoresist pattern photo formed by Example 3 of the present invention.

5 is a pattern of the etching layer pattern after the etching process of Example 3 of the present invention.

<Brief description of the main parts of the drawing>

1, 21, 121: semiconductor substrate 3, 23, 123: etched layer

5: amorphous carbon film 7: insulating film

9: antireflection film 11, 29, 129: photoresist pattern

25: first multifunction hard mask film 27: second multifunction hard mask film

31: Footing phenomenon 123-1: Etch layer pattern

125: Multifunction Hard Mask Film 125-1: Multifunction Hard Mask Film Pattern

127: intermixing prevention film 127-1: mixing prevention film pattern

131: lower photoresist pattern

The present invention relates to a composition for preventing mixing of an interface between a hard mask film and a photoresist film and a method of manufacturing a semiconductor device using the same.

As the application fields of semiconductor memory devices are expanded, there is an urgent need for process development for manufacturing high-capacity memory devices with improved integration.

Accordingly, a general semiconductor manufacturing process essentially includes a lithography process for forming a gate-line pattern or a bit-line contact hole pattern.

The lithography process uses ArF (193 nm, VUV (157 nm) or EUV (13 nm) instead of long wavelength light sources such as I-line or KrF (248 nm) as an exposure light source to form a pattern critical dimension (CD) of 0.07 μm or less. It was developed to use the same short wavelength light source and a suitable photoresist material.

Meanwhile, in order to prevent the photoresist pattern from collapsing during the lithography process, the coating thickness of the photoresist film is reduced, which makes it difficult to secure the etching selectivity of the photoresist pattern during the etching process.

In order to solve this problem, a conventional semiconductor device manufacturing method uses a multilayer hard mask film having an etching selectivity relatively larger than that of a photoresist pattern between an etched layer and a photoresist pattern. For example, a hard mask film having a complex multilayer structure composed of one or more layers such as an amorphous carbon film 5 and an insulating film 7 is formed on the etched layer 3 on the semiconductor substrate 1, and then an antireflection film is formed thereon. 9) and a method of sequentially forming the photoresist pattern 11 having a predetermined region opened (see FIG. 1).

At this time, the amorphous carbon film, the insulating film or the anti-reflection film should use a deposition equipment separate from the process equipment used for the photoresist coating process, the throughput of the deposition equipment (throughput) is 50 sheets or less per hour, forming 150 sheets per hour Since it is lower than the yield of the photoresist coating process, more deposition equipment is needed to increase productivity, and the process cost increases.

Therefore, in order to simplify the process and reduce the cost and equipment space, a multifunctional hard mask film, which can be used as a hard mask film as well as acting as an organic antireflection layer, has been introduced.

That is, the method of introducing the multifunctional hard mask film may include the first multifunctional hard mask film 25 and the organic anti-reflection film formed of a general organic polymer on the etched layer 23 on the semiconductor substrate 21 as illustrated in FIG. 2. Forming a second multifunction hard mask layer 27 having a function, and then sequentially forming a photoresist pattern 29 having a predetermined region opened thereon.

In this case, the second multifunctional hard mask layer having the function of the organic anti-reflection film should include a sufficient amount of silicon (Si) to secure the etching resistance to the lower layer. However, this results in an intermixing reaction at the interface between the hard mask film and the photoresist film, thereby causing a footing phenomenon 31 in which the profile of the photoresist pattern is not vertically formed but spreads slowly. do. As a result, it is difficult to transfer the vertical profile to the lower etched layer during the etching process on the etched layer, and the control of the critical dimension becomes difficult.

In order to overcome these disadvantages, the present inventors have proposed a new concept that can secure the etching selectivity to the underlying etching layer while preventing the mutual mixing reaction occurring at the interface of the anti-reflection film and the photoresist film. The present invention has been completed by developing a composition for preventing mixing of a hard mask film and a photoresist film interface and a method of manufacturing a semiconductor device using the same.

An object of the present invention is to provide a composition for preventing mixing that can prevent a mutual mixing reaction between an antireflection film and a photoresist surface when manufacturing a semiconductor device.

Moreover, an object of this invention is to provide the manufacturing method of the semiconductor element which can form a uniform pattern using the said composition for prevention of mixing.

In order to achieve the above object, the present invention provides a composition for preventing the mixing of the interface between the hard mask film and the photoresist film comprising a compound of Formula 1 and an organic solvent capable of forming crosslinks by heat:

[Formula 1]

Where

R is C ₁ -C ₁₀ substituted or unsubstituted alkylene,

n and m are integers from 1 to 20.

Preferably, R is C ₁ ~ C ₅ substituted or unsubstituted alkylene, n is an integer of 1 to 10, m is an integer of 1 to 15.

The organic solvent is not particularly limited as long as it is an organic solvent used as a conventional antireflection film solvent. For example, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, cyclohexanone, propylene glycol monomethyl ether acetate At least one solvent selected from the group consisting of (PGMEA), 2-heptanone and ethyl lactate. The organic solvent is included in an amount of 2,000 to 10,000 parts by weight, preferably 5,000 to 10,000 parts by weight, based on 100 parts by weight of the compound of Formula 1, and when the content of the organic solvent exceeds 10,000 parts by weight, a sufficient thickness of the mixing prevention film is obtained. If less than 2,000 parts by weight, the anti-mixing film is formed thick, and it is difficult to etch the pattern vertically.

Since the compound of Formula 1 is cured, such as acryl is cured when crosslinking is formed at a high temperature to form a polymer, the compound of Formula 1 is not dissolved in a photoresist solvent during a subsequent step of forming a photoresist film. In addition, since the etching process is faster than the photoresist film and the etching process is slower for the lower multi-function hard mask film, the etching selectivity for the multi-function hard mask film can be secured.

In addition, the composition for preventing mixing of the interface between the hard mask film and the photoresist film of the present invention comprises at least one crosslinking agent or a catalyst such as a novolak-based resin containing a hydroxyl group in order to further increase the density of crosslinking between the compounds of the formula (1) during baking. It may further include.

In this case, the novolak-based resin has a molecular weight of 100 to 5,000, and includes 1 to 20 parts by weight based on 100 parts by weight of the compound of Formula 1.

Since the novolac-based resin shows high absorbance with respect to a DUV light source, particularly an ArF light source of 193 nm, it is possible to increase the effect of removing reflected light and standing waves generated from the lower layer. The novolak-based resin may be represented by a compound of Formula 2a or a compound of Formula 2b,

[Formula 2a]

[Formula 2b]

Where

n is an integer of 1 to 500, preferably 1 to 200.

In addition, the catalyst may be a thermal acid generator and photoacid generator.

In this case, the content of the catalyst may be appropriately selected within a range capable of performing a catalyst function, for example, may be added in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the compound of Formula 1.

The thermal acid generator may generally use a material used as a conventional thermal acid generator, and it is preferable to use at least one selected from the group consisting of the following Chemical Formulas 3a and 3b.

[Formula 3a]

[Formula 3b]

Wherein A is a functional group containing a sulfonyl group,

또는

이고, Preferably

or

ego,

n is 0 or 1;

In addition, the photoacid generator is phthalimidotrifluoromethanesulfonate, dinitrobenzyltosylate, n-decyldisulfone, naphthylimidotrifluoromethanesulfonate, diphenylparamethoxyphenyl sulfonium triflate, di Phenylparatoluenyl sulfonium triplate, diphenylparaisobutylphenyl sulfonium triplate, triphenyl hexafluoro arsenate, triphenyl hexafluoro antimonate, triphenylsulfonium triflate or dibutylnaphthylsul Phosphon triflate and the like.

If the composition for preventing mixing of the hard mask film and the photoresist film interface of the present invention includes the thermal acid generator or the photoacid generator, an acid is generated from the thermal acid generator or the photoacid generator during the baking process or the exposure process. In the presence of the acid thus generated, the crosslinking reaction between the compound of Formula 1 and the crosslinking agent is further activated, whereby a mixing prevention film that is not dissolved in the solvent of the photoresist is more easily formed.

In the present invention,

(a) forming a multifunctional hard mask layer on the etched layer;

(b) coating a composition for preventing mixing between the hard mask film and the photoresist film interface of the present invention on the hard mask film and baking the same to form a mixing prevention film;

(c) forming a photoresist pattern on the mixing prevention film;

(d) patterning the mixing prevention layer and the multifunctional hard mask layer using the photoresist pattern as an etching mask to form a stacked pattern in which a multifunction hard mask layer pattern and a mixing prevention layer pattern are sequentially formed; And

(e) patterning an etched layer by using the stacked pattern as an etch mask to form an etched layer pattern.

In this case, the multifunctional hard mask film may be formed of at least one selected from the group consisting of an amorphous carbon layer, an insulating film, a polymer layer having a high carbon content, and an organic antireflection film.

The baking process of step (b) is performed at a temperature of 100 to 300 ° C. for 1 to 5 minutes to activate crosslinking between the compounds in the composition of the present invention, so that the solvent contained in the photoresist is subjected to a subsequent photoresist coating process. It is possible to form a mixing prevention film that does not dissolve and does not react with the multifunctional hard mask film.

If the crosslinking bond is not sufficiently formed in the anti-mixing composition of the present invention, the anti-mixing film is easily dissolved in the photoresist solvent, and if the crosslinking is excessively formed, the crosslinking density is increased and the anti-mixing film is etched later than the photoresist film. The etching rate is reduced.

As such, the anti-mixing film formed by using the anti-mixing composition of the present invention does not dissolve in the photoresist solvent, thereby preventing mutual mixing reaction between the hard mask film and the interface of the photoresist film. Can be prevented. In addition, since the anti-mixing layer is etched later than the lower multi-functional hard mask layer during the etching process, it is possible to secure an etch selectivity for the multi-functional hard mask layer or the etching target layer, and the conventional photoresist film forming equipment (track) It can be formed by using the productivity can be improved to reduce the investment cost. In addition, it can be easily removed through a conventional removal process, an etching process using a gas.

Hereinafter, the pattern forming method of the semiconductor device of the present invention will be described in more detail with reference to the drawings.

Referring to FIG. 3A, an etched layer 123 is formed on the substrate 121, and a multifunctional hard mask layer 125 is deposited on the substrate 121.

The etched layer is formed using a silicon oxynitride film or a silicon oxide film.

In addition, the multifunctional hard mask film is formed of at least one film selected from the group consisting of an amorphous carbon layer, an insulating film, a polymer layer having a high carbon content, and an organic antireflection film.

Subsequently, the anti-mixing composition of the hard mask film and the photoresist film interface of the present invention is coated on the multifunctional hard mask film 125, and then a baking process is performed to form the anti-mixing film 127.

At this time, the baking process is performed for 1 to 5 minutes at 100 to 300 ℃, the mixing prevention film is formed to a thickness of about 500 ~ 1500Å.

Next, a conventional chemically amplified photoresist film is formed on the mixing prevention film 127 of the present invention and then patterned to form a photoresist pattern 129. At this time, the footing phenomenon does not occur in the lower portion of the photoresist 131.

Using the photoresist pattern 129 of FIG. 3A as an etch mask, a patterning process is performed on the anti-mixing layer 127 and the multifunctional hard mask layer 125 of the present invention, as shown in FIG. 3B. A pattern in which the pattern 125-1, the mixing prevention film pattern 127-1, and the photoresist pattern 129 are sequentially stacked is formed.

In this case, the patterning process uses at least one gas selected from the group consisting of Cl ₂ , Ar, N ₂ O ₂ , CF ₄ and C ₂ F ₆ .

Subsequently, an etching process is performed on the lower etching layer 123 using the stacked pattern of FIG. 3B as an etching mask to form an etching layer pattern 123-1 as illustrated in FIG. 3C.

By performing a general removal process on the resultant of FIG. 3C to remove all of the stacked patterns used as the etch masks, as shown in FIG. 3D, a uniform etched layer pattern 123-1 is formed on the substrate 121. To form.

The composition for preventing the mixing of the hard mask film and the photoresist film interface according to the present invention and the method for manufacturing a semiconductor device are ultra-short wavelength, preferably ArF light source such as KrF, VUV, EUV, E-beam, X-ray or ion beam. It can apply to a fine pattern formation process.

In addition, the present invention provides a semiconductor device manufactured by the method for manufacturing a semiconductor device including the pattern forming step.

Hereinafter, the present invention will be described in detail by way of examples. However, the following examples are only for illustrating the present invention, and the contents of the present invention are not limited by the following examples.

I. Preparation of the Compositions of the Invention

Example 1

Compound 1 of Formula 1 (n = 2, m = 13, R = CH ₂ , Toagosei Co. Ltd. (trade name: M260), Tg = -34 ° C.) (1 g) was substituted with methyl 3-methoxy propionate (70 ml ), And stirred at room temperature for 60 minutes. The reaction solution was passed through a 0.2 μm microfilter to prepare a composition for preventing mixing between the hard mask film and the photoresist film interface.

Example 2

Compound 1 of Formula 1 (n = 2, m = 13, R = CH ₂ , Toagosei Co. (M260)) (1 g), compound of Formula 2b (0.2 g) having an average molecular weight of 2,000 and 2- Hydroxyhexyl paratoluenylsulfonate (0.02 g) and photophenyl generator trephenylsulfonium triflate (0.03 g) were dissolved in propylene glycol monomethyl ether acetate (PGMEA) (70 g), followed by a 0.2 μm fine filter. By passing through to prepare a composition for preventing mixing of the interface between the hard mask film and the photoresist film of the present invention.

II. Pattern Formation Method

Example 3

An oxynitride film (2000Å) and an SOC film (Nissan Chemical, NCA9004A) (2000Å) were coated on a hexamethyldisilazane (HMDS) treated silicon wafer with an etched layer, followed by a multifunctional hard mask film (Nissan Chemical, NCH087) ) Was deposited.

On top of that, the anti-mixing composition (5 ml) of Example 1 was spin-coated at 3000 rpm and then baked at 200 ° C. for 90 seconds to form a 110 μm thick anti-mixing film.

A 193 nm photoresist film (Shin-Etsu, RHR4473) was coated on the anti-mixing layer to a thickness of 1400 kPa, baked at 120 ° C. for 90 seconds, and then exposed using an ArF scanner (NA = 0.85, ASML). It was further baked at 120 ° C. for 90 seconds. After the baking was completed, it was developed with a 2.38 wt% TMAH developer to form a photoresist pattern of 70 nmL / S (see FIG. 4).

Subsequently, the anti-mixing layer and the hard mask layer are sequentially etched using the photoresist pattern as an etch mask to form a pattern in which the anti-mixing layer pattern and the hard mask layer pattern are stacked. An etch process was performed on the etched layer to form an etched layer pattern of 70 nm L / S (see FIG. 5). In this case, each etching process used a CF ₄ / O ₂ mixed etching gas (RF power: about 700 W, bias power: about 150 W).

Example 4

70 nmL / S in the same manner as in Example 3 except for using the composition for preventing the mixing of the hard mask film and the photoresist film interface instead of the composition of Example 1 used in Example 3 Each layer pattern was obtained.

As described above, in the present invention, when the composition for preventing the mixing of the interface between the multi-function hard mask film and the photoresist film is used, the mutual mixing reaction does not occur between the interface between the hard mask film and the photoresist film during the subsequent photoresist film forming process. Therefore, the footing phenomenon can be prevented from occurring under the photoresist pattern, and the vertical uniform pattern shape can be transferred to the lower layer.

Claims (15)

A composition for preventing mixing of a hard mask film and a photoresist film interface comprising (i) a compound of formula 1 and (ii) an organic solvent: [Formula 1]

Where R is C ₁ -C ₁₀ substituted or unsubstituted alkylene, n and m are integers from 1 to 20. The method of claim 1, R is C ₁ ~ C ₅ substituted or unsubstituted alkylene, n is an integer of 1 to 10, m is an integer of 1 to 15, the composition for preventing mixing of the interface between the hard mask film and the photoresist film . The method of claim 1, The organic solvent is selected from the group consisting of ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, cyclohexanone, propylene glycol monomethyl ether acetate (PGMEA), 2-heptanone and ethyl lactate. Mixing prevention composition characterized by the above solvent. The method of claim 1, The organic solvent is an anti-mixing composition, characterized in that contained in 2,000 to 10,000 parts by weight based on 100 parts by weight of the compound of Formula 1. The method of claim 4, wherein The organic solvent is an anti-mixing composition, characterized in that contained in 5,000 to 10,000 parts by weight based on 100 parts by weight of the compound of Formula 1. The method of claim 1, The anti-mixing composition further comprises at least one additive selected from the group consisting of a crosslinking agent and a catalyst. The method of claim 6, Said crosslinking agent is novolak-type resin of molecular weight 100-5,000, The composition for preventing mixing. The method of claim 7, wherein The novolak-based resin is a compound for preventing mixing, characterized in that the compound of Formula 2a or the compound of Formula 2b: [Formula 2a]

[Formula 2b]

Where n is an integer from 1 to 500. The method of claim 6, The catalyst is a mixture preventing composition, characterized in that at least one selected from the group consisting of a thermal acid generator and a photoacid generator. The method of claim 9, The thermal acid generator is characterized in that at least one selected from the group consisting of Formula 3a and Formula 3b, The photoacid generator is phthalimido trifluoromethanesulfonate, dinitrobenzyltosylate, n-decyldisulfone, naphthylimidotrifluoromethanesulfonate, diphenylparamethoxyphenyl sulfonium triflate, diphenylpara Toluenyl sulfonium triplate, diphenylparaisobutylphenyl sulfonium triplate, triphenyl hexafluoro arsenate, triphenyl hexafluoro antimonate, triphenylsulfonium triflate and dibutylnaphthylsulfonium tri Mixing prevention composition, characterized in that at least one selected from the group consisting of: [Formula 3a]

[Formula 3b]

Where A is a functional group containing a sulfonyl group, and n is 0 or 1. The method of claim 6, The crosslinking agent is included in 0.1 to 10 parts by weight based on 100 parts by weight of the compound of Formula 1, and the catalyst agent is contained in 0.1 to 10 parts by weight based on 100 parts by weight of the compound of Formula 1. (a) forming a hard mask layer on the etched layer; (b) coating an anti-mixing composition according to claim 1 on the hard mask layer and baking to form a mixing prevention film; (c) forming a photoresist pattern on the mixing prevention film; (d) patterning the mixing prevention layer and the multifunctional hard mask layer using the photoresist pattern as an etching mask to form a stacked pattern in which a multifunction hard mask layer pattern and a mixing prevention layer pattern are sequentially formed; And (e) patterning the etched layer using the stacked pattern as an etch mask to form an etched layer pattern. The method of claim 12, The hard mask film is a semiconductor device manufacturing method, characterized in that at least one selected from the group consisting of an amorphous carbon layer, an insulating film, a high carbon content polymer layer and an organic antireflection film. The method of claim 12, The baking process of step (b) is a method for manufacturing a semiconductor device, characterized in that performed for 1 to 5 minutes at a temperature of 100 to 300 ℃. The method of claim 12, The thickness of the said mixing prevention film is 500-1500 kPa, The manufacturing method of the semiconductor element characterized by the above-mentioned.

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