KR20110088809A - Composition for photosensitive type developed bottom anti-reflective coating, fabricating method of patterns using the same, and fabricating method of semiconductor device using the same - Google Patents

Abstract

PURPOSE: A composition for forming a photosensitive type anti-reflective coating, a pattern forming method using the same, and a semiconductor device manufacturing method using the same are provided to form superior trench patterns based on little amount of exposed light. CONSTITUTION: A composition for forming a photosensitive type anti-reflective coating includes a photoacid generator containing onium salt and a photo-resist agent reacting with i-line light. The onium salt includes sulfonate. The sulfonate includes a sulfonate cation part represented by chemical formula 1 and a sulfonate anion part represented by chemical formula 2. In the chemical formula 1, the A, the B, and the C includes C1 to C20 alkyl group, C2 to C20 alkoxy group, C4 to C20 aryl group, C3 to C20 cyclo alkyl group, or C5 to C20 alkoxycyclo alkyl group. In the chemical formula 2, the n is 1 to 3. The X includes C4 to C10 cyclic group, alkyl group, cycloalkyl group, and other groups.

Description

Composition for photosensitive antireflection film formation, pattern formation method using same and manufacturing method of semiconductor device using same {Composition for photosensitive type developed bottom anti-reflective coating, fabricating method of patterns using the same, and fabricating method of semiconductor device using the same}

The present invention relates to a composition for forming a photosensitive type anti-reflective coating (DBARC), a pattern forming method using the same, and a method for manufacturing a semiconductor device using the same. The present invention relates to a composition for forming a photosensitive antireflection film, a pattern forming method using the same, and a method of manufacturing a semiconductor device using the same.

In the semiconductor manufacturing process, the etching process occupies a large proportion, and as the integration of semiconductor devices is recently increased, photolithography process technology is widely used to form fine patterns of semiconductor devices.

The photolithography process forms a mask pattern, for example, a photoresist pattern, and performs an etching process on the object to be etched using the photoresist pattern as an etching mask. In this case, in the exposure process applied in the photolithography process, an anti-reflection film may be applied to reduce the reflection of the etched film to the light.

The problem to be solved by the present invention is to provide a composition for forming a photosensitive anti-reflection film that can form an etch pattern having an improved profile.

Another object of the present invention is to provide a pattern forming method using a composition for forming a photosensitive antireflection film capable of forming an etch pattern having an improved profile.

Another object of the present invention is to provide a method of manufacturing a semiconductor device using a composition for forming a photosensitive antireflection film capable of forming an etch pattern having an improved profile.

The objects of the present invention are not limited to the above-mentioned technical problem, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

The composition for forming a photosensitive antireflection film according to an embodiment of the present invention for solving the above problems includes a photoacid generator including an onium salt, and a photoresist that reacts with i-line light.

The pattern forming method using the composition for forming a photosensitive antireflection film according to an embodiment of the present invention for solving the other problems, the first photoacid generator comprising an onium salt on the etching film and the eye line (i-line) Coating a composition for forming a photosensitive antireflection film comprising a photosensitive agent reacting with light to form a photosensitive antireflection film, forming a photoresist film on the photosensitive antireflection film, and irradiating eyeline light to the photoresist film and the photosensitive film. Simultaneously exposing an antireflection film, developing the exposed photoresist film and the photosensitive antireflection film to form a photosensitive antireflection film pattern and a photoresist pattern, and patterning the etching target film using the photoresist pattern as an etching mask. .

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device using the composition for forming a photosensitive antireflection film, including providing a substrate, forming an etched film on the substrate, and forming a etched film on the etched film. A photosensitive antireflective coating film-forming composition comprising a first photoacid generator including an onium salt and a photosensitive agent reacting with i-line light is coated to form a photosensitive antireflection film, and a photo is formed on the photosensitive antireflection film. Forming a resist film, irradiating eyeline light to simultaneously expose the photoresist film and the photosensitive antireflection film, and developing the exposed photoresist film and the photosensitive antireflection film to form a photosensitive antireflection film pattern and a photoresist pattern, The etched film is patterned using the photoresist pattern as an etch mask to form a pattern on the substrate. It includes forming a pattern expression cornea.

Other specific details of the invention are included in the detailed description and drawings.

1 to 5 are cross-sectional views for explaining a pattern forming method using the composition for forming a photosensitive antireflection film according to an embodiment of the present invention.
6A and 6B are SEM photographs of patterns formed by applying a heat type antireflection film and a photosensitive type antireflection film, respectively.
7A and 7B are V-SEM (Virtical Scanning Electron Microscope) photographs of patterns formed by applying a heat type anti-reflection film and a photosensitive type anti-reflection film, respectively.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Thus, in some embodiments, well known process steps, well known structures and well known techniques are not described in detail in order to avoid obscuring the present invention.

When an element is referred to as being "connected to" or "coupled to" with another element, it may be directly connected to or coupled with another element or through another element in between. This includes all cases. On the other hand, when one device is referred to as "directly connected to" or "directly coupled to" with another device indicates that no other device is intervened. Like reference numerals refer to like elements throughout. “And / or” includes each and all combinations of one or more of the items mentioned.

Although the first, second, etc. are used to describe various elements, components and / or sections, these elements, components and / or sections are of course not limited by these terms. These terms are only used to distinguish one element, component or section from another element, component or section. Therefore, the first device, the first component, or the first section mentioned below may be a second device, a second component, or a second section within the technical spirit of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. As used herein, the term "comprises" and / or "comprising" refers to the presence of one or more other components, steps, operations and / or elements. Or does not exclude additions. And "and / or" include each and any combination of one or more of the mentioned items. In addition, like reference numerals refer to like elements throughout the following specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in a meaning that can be commonly understood by those skilled in the art. In addition, terms defined in a commonly used dictionary are not ideally or excessively interpreted unless they are clearly defined in particular.

Hereinafter, a composition for forming a photosensitive antireflection film, a pattern forming method using the same, and a method of manufacturing a semiconductor device using the same according to embodiments of the present invention will be described in detail with the accompanying drawings.

First, the composition for forming a photosensitive antireflection film according to an embodiment of the present invention will be described in detail.

The composition for forming a photosensitive antireflection film according to an embodiment of the present invention includes a photo acid generator including an onium salt, and a sensitizer reacting to i-line light. Include.

The onium salt of the photoacid generator may include a sulfonium salt, but may include a sulfonium salt cation moiety represented by Chemical Formula 1 and a sulfonium salt anion moiety represented by Chemical Formula 2.

<Formula 1>

<Formula 2>

(However, in Formula 1, A, B, C are each an alkyl group having 1 to 20 carbon atoms, an alkoxy alkyl group having 2 to 20 carbon atoms, an aryl group having 4 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or An alkoxy cycloalkyl group having 5 to 20 carbon atoms, wherein n is 1 to 3, and X is a cycloheptane including a cyclo group having 4 to 10 carbon atoms, an alkyl group, a cycloalkyl group, an adamantal group, and oxygen Includes a flag.)

In some embodiments, the sulfonium salt of the photoacid generator is a material represented by the following Chemical Formula 3.

<Formula 3>

The photoacid generator of Chemical Formula 3 may react with light to generate a photoacid generator represented by the following Structural Formula 4. In this case, the reaction of the photoacid generator of Formula 3 with light may mean that the photoacid generator is activated by the photosensitive agent absorbing the eyeline light source to generate an acid.

<Formula 4>

(Wherein n is 1 in Formula 4)

Photosensitizers are photosensitizers that react to i-line light. More specifically, the photosensitizer of the present invention absorbs the eye line light to activate the acid generating reaction of the photoacid generator. That is, the photoresist for preparing the probe array according to the embodiments of the present invention includes a photoresist that reacts to the eyeline light, such that a photoacid generator including an onium salt that does not react to the eyeline light due to the characteristics of the chromophore absorbs the eyeline. Activated by one photosensitizer, the acid production reaction begins.

For example, the photosensitizer is 2,4-isopropyl thioxanthone (ITX), benzophenone (BP), and butyl represented by Chemical Formulas 5-1 to 5-3, respectively. It may include at least one of Butyl Benzyl Phthalate (BPB).

<Formula 5-1>

<Formula 5-2>

<Formula 5-3>

Here, the eye line may refer to light having a wavelength of about 365 nm.

In addition, the composition for forming a photosensitive antireflection film of the present invention may further include a polymer resin as described below. For example, it may include a material represented by the following formula (6).

<Formula 6>

The composition for photosensitive antireflection film formation of this invention may further contain a crosslinking agent. The crosslinking agent is a substance for crosslinking the polymer resin. The composition for forming a photosensitive antireflection film according to an embodiment of the present invention may include, for example, a thermal crosslinking agent. Furthermore, the composition for forming a photosensitive antireflection film according to an embodiment of the present invention may include a material represented by the following Chemical Formula 7.

<Formula 7>

The composition for forming a photosensitive antireflection film according to an embodiment of the present invention may include, for example, about 10 to 40% by weight of a polymer resin, about 1 to 10% by weight of a photoacid generator, about 1 to 10% by weight of a photosensitive agent, and about 5 to about a crosslinking agent. To 20% by weight and excess solvent. The extra solvent may include, for example, an organic solvent, such as a PGMEA / GBL mixed solvent.

According to the composition for forming a photosensitive antireflection film according to an embodiment of the present invention, a pattern may be formed in a photosensitive type rather than a thermal type with respect to an i-line light source, thereby providing image contrast. Can be improved to form a pattern having a better profile.

Hereinafter, a pattern forming method using the photosensitive antireflection film composition according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. 1 to 5 are cross-sectional views of intermediate structures for explaining a pattern forming method using the photosensitive antireflection film composition according to an embodiment of the present invention.

Referring to FIG. 1, a photosensitive antireflection film-forming composition including a first photoacid generator including an onium salt and a photosensitive agent reacting with an i-line light is coated on the etched film 102. An antireflection film 104 is formed.

The etched film 102 may be, for example, a material layer formed on the semiconductor substrate 100. Examples of the material layer may include a silicon nitride film, a polysilicon film, or a silicon oxide film, but are not limited thereto. Further, although not shown in the drawings, the surface of the etching target film 102 may be pre-cleaned to remove contaminants remaining on the etching target film 102.

The photosensitive antireflection film 104 may include a composition for forming a photosensitive antireflection film including a first photoacid generator including an onium salt and a photoresist that reacts to eye line light. The content of the composition for forming a photosensitive antireflection film used in the embodiments of the present invention is substantially the same as described above.

Subsequently, after the photosensitive antireflection film 104 is formed, a drying and baking process is performed to cause cross linking of the photosensitive antireflection film 104. For example, the bake process may proceed for about 50 seconds at a temperature of about 150 to about 210 ° C.

Next, referring to FIG. 2, a photoresist film 106 is formed on the photosensitive antireflection film 104.

More specifically, the photoresist film 106 may be formed by coating a photoresist on the photosensitive antireflection film 104. In this case, the photoacid generator included in the photoresist film 106 may be a material different from that of the photoacid generator included in the photosensitive antireflection film 104. In some other embodiments, the same photoacid generator may be used.

In addition, a soft bake process may be performed on the substrate 100 on which the photoresist film 106 is formed. For example, the soft bake process may be performed at a temperature of about 100 to about 160 ° C. for about 50 seconds.

Next, referring to FIG. 3, the eye line light is irradiated to simultaneously expose the photoresist film 106 and the photosensitive antireflection film 104.

More specifically, the exposure mask 110 may be disposed on the photoresist film 106 using the exposure apparatus. The exposure mask 110 includes a predetermined pattern, and a predetermined portion of the photoresist film 106 formed on the substrate 100 passes through the exposure mask 110 by irradiating eye line light on the exposure mask 110. May react selectively with line light. The i-line light may be, for example, light having a wavelength of about 365 nm. Furthermore, an exposure reaction also occurs in the photosensitive antireflection film 104 existing below the photoresist film 106 by such an exposure process.

For example, when the photoresist film 106 is a positive type photoresist, the photoresist film 106b in the exposed area is relatively hydrophilic in comparison with the photoresist film 106a in the non-exposed area. Can have Accordingly, the photoresist film 106b in the exposed region and the photoresist film 106a in the non-exposed region may have different solubility. In addition, the photosensitive antireflection film 104 may also include an exposure area 104b and a non-exposure area 104a.

Subsequently, a baking process is performed so that the predetermined pattern defined in the photoresist film 106 and the photosensitive antireflection film 104 is easily dissolved in a specific solvent. For example, the baking process may proceed for about 50 seconds at a temperature of about 100 to 160 ° C.

In some embodiments, when the photoresist film 106 and the photosensitive antireflection film 104 are, for example, of positive type, the photoresist film 106b of the exposed area, that is, the exposed area, is exposed by the previous exposure process. The photosensitive antireflection film 104b in the exposed region may be in a state in which it is easily dissolved in a specific solvent. On the contrary, when the photoresist film 106 and the photosensitive antireflection film 104 are of a negative type, the non-exposed areas may be in a state in which a particular solvent is easily dissolved. Since this is obvious to those skilled in the art, the positive type photoresist film 106 and the photosensitive antireflection film 104 will be described below by way of example, and the detailed description of the negative type will be omitted. do.

Next, referring to FIG. 4, the exposed photoresist film 106b and the photosensitive antireflection film 104b are developed to form the photosensitive antireflection film pattern 112 and the photoresist pattern 108.

More specifically, by using a developer, the photoresist film 106b in the exposed area and the photosensitive antireflection film 104b in the exposed area are dissolved and removed to remove the photoresist pattern 108 and the photosensitive antireflection film pattern 112. Can be formed. In other words, the photoresist film 106b of the exposed area and the photosensitive antireflection film 104b of the exposed area are sequentially dissolved and then removed to form the photoresist pattern 108 and then to form the antireflection film pattern. There is no need to perform a separate etching process. Therefore, there is an advantage in that the loss of the photoresist pattern 108 can be prevented.

Furthermore, when the composition for forming a photosensitive antireflection film according to the embodiment of the present invention is applied, image contrast is much better, thereby forming a pattern having a further improved profile.

Next, referring to FIG. 5, the etching target film 112 is patterned using the photoresist pattern 108 as an etching mask.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Hereinafter, a method of manufacturing a semiconductor device using the photosensitive antireflection film composition according to an embodiment of the present invention will be described.

A method of manufacturing a semiconductor device using the photosensitive antireflection film composition according to an embodiment of the present invention includes providing a substrate, forming an etching film on the substrate, and a first photoacid generator including an onium salt on the etching film; Coating a composition for forming a photosensitive antireflection film comprising a photoresist that reacts to eye line light to form a photosensitive antireflection film, forming a photoresist film on the photosensitive antireflection film, and irradiating eyeline light to the photoresist film and the photosensitive antireflection film Simultaneously, exposing the exposed photoresist film and the photosensitive antireflection film to form a photosensitive antireflection film pattern and a photoresist pattern, and patterning the etch film with the photoresist pattern as an etch mask to form an etch pattern on the substrate. It includes.

Since the method of manufacturing a semiconductor device according to an embodiment of the present invention is similar in that it uses a photosensitive antireflection film composition and a pattern forming method using the same according to an embodiment of the present invention described above, a more specific description thereof Is omitted.

More detailed information about the present invention will be described through the following specific experimental examples, and details not described herein will be omitted because it is sufficiently technically inferable to those skilled in the art.

< Experimental Example  A>

To prepare a 10g solution of the formula 8-1 and 0.5g of the photoacid generator of the formula 8-2 was dissolved in a 9: 1 mixed solution of tetrahydrofuran: water (H ₂ O). The pH of the prepared solution was measured (measurement of pH before exposure), and the pH was measured after exposing the solution with an i-line light source of 365 nm. Comparative Example 1, Comparative Example 2

<Formula 8-1>

<Formula 8-2>

The photoacid generator of Formula 8-1 and the photosensitive agent of Formula 8-3 were mixed at a weight ratio of 1: 1 to prepare a 10g solution. The pH of the prepared solution was measured (measurement of pH before exposure), and the pH was measured after exposing the solution with an eyeline light source of 365 nm. Experimental Example 1

<Formula 8-3>

The results of measuring the pH of each solution for various exposure doses are shown in Table 1 below.

Table 1 pH Measurement Results According to Exposure Energy Time (sec) 0 10 20 30 40 50 80 270 Exposure energy (mJ) 0 135 270 405 540 675 1080 3645 Comparative Experimental Example 1 (pH) 6.25 6.95 6.87 6.75 6.69 6.44 6.01 4.5 Comparative Experimental Example 2 (pH) 5.39 5.07 5.06 5.12 5.11 5.14 5.14 5.1 Experimental Example 1 (pH) 4 3.91 3.77 3.68 3.63 3.62 3.38 2.51

Referring to Table 1, in Comparative Experimental Example 1 and Comparative Example 2 was measured a relatively high pH compared to Experimental Example 1. That is, in Experimental Example 1, it was found that acid was generated in the solution even with a relatively low exposure amount. More specifically, the pHs of Comparative Experiment 1 and Comparative Example 2 were 6.95 and 5.07, respectively, at an exposure energy of 135 mJ, whereas the pH of Experiment 1 was 3.91. That is, Experimental Example 1 including a photoacid generator including an onium salt and a photoresist reacting with an eye line, Comparative Experimental Example 1 including only a photoacid generator including an onium salt and a non-ion type photoacid generator It can be seen that a lower pH can be obtained with less exposure energy than Comparative Experimental Example 2 including.

< Experimental Example  B>

6A and 6B show a pattern formed by applying a thermal type DBARC and a photosensitive type DBARC according to an embodiment of the present invention, respectively. 6A is a scanning electron microscope (SEM) photograph of patterns formed by applying an anti-reflection film of a thermal type, and FIG. 6B illustrates patterns formed by applying an anti-reflection film of a photosensitive type according to an embodiment of the present invention. SEM picture. The number written at the top of each picture is the exposure amount (unit: msec) provided at the time of pattern formation, and the number written at the bottom is the trench size (unit: um).

6A and 6B, when the anti-reflective coating of the thermal type is applied, the exposure amount is increased to 380 msec, after exposure and development, a photoresist pattern is formed, but no DBARC pattern is formed, and DBARC residue remains on the lower substrate. And it was found. On the contrary, when the photosensitive type anti-reflection film according to the embodiment of the present invention was applied, it was confirmed that the DBARC was developed without residue on the lower substrate at an exposure amount of 380 msec. It was also confirmed that a DBARC pattern was formed even with a small exposure amount of 200 msec.

That is, the application of the anti-reflection film of the photosensitive type according to the embodiment of the present invention means that a trench having a much better profile can be formed than the application of the anti-reflection film of the thermal type. The case where the photosensitive type antireflection film according to the embodiment is applied means that a better trench pattern can be formed even with a smaller exposure amount than when the column type antireflection film is applied.

< Experimental Example  C>

A photoresist pattern and an antireflection film formed using a pattern formed by applying an anti-reflection film of a thermal type, and a composition for forming a photosensitive antireflection film according to an embodiment of the present invention including Chemical Formula 3 and Chemical Formula 5-1. The patterns are shown in FIGS. 7A and 7B, respectively. FIG. 7A is a V-SEM photograph of patterns formed by applying an anti-reflection film of a thermal type, and FIG. 7B is a V-SEM of patterns formed by applying an anti-reflection film of a photosensitive type according to an embodiment of the present invention. It is a photograph.

In the case of FIG. 7A, the thickness of the antireflection film was 600 kPa and the thickness of the photoresist film was 4000 kPa. In the case of FIG. 7B, the thickness of the antireflection film was 600 kPa and the photoresist film was 7000 kPa.

Referring to FIG. 7A, when a heat type anti-reflection film is applied, webs and footings are generated in the photoresist and the anti-reflection film pattern. On the contrary, referring to FIG. 7B, although the thickness of the photoresist film is much thicker than that of FIG. 7A, a clearer photoresist pattern and an anti-reflection film pattern could be obtained. This, the photosensitive antireflection film pattern formed by using the composition for forming a photosensitive antireflection film according to an embodiment of the present invention applied to Figure 7b is more sensitive to the eye line light source, it can be seen that the acid generation sufficiently occurred.

100 semiconductor substrate 102 etched film
104: photosensitive antireflection film 106: photoresist film
108: photoresist pattern 110: exposure mask
112: photosensitive antireflection film pattern

Claims (10)

Photoacid generators including onium salts; And
A composition for forming a photosensitive antireflection film comprising a photoresist that reacts to i-line light. The method according to claim 1,
The onium salt comprises a sulfonium salt, wherein the sulfonium salt is a composition for forming a photosensitive anti-reflection film comprising a sulfonium salt cation portion represented by the formula (1) and a sulfonium salt anion portion represented by the formula (2).
<Formula 1>

<Formula 2>

(However, in Formula 1, A, B, C are each an alkyl group having 1 to 20 carbon atoms, an alkoxy alkyl group having 2 to 20 carbon atoms, an aryl group having 4 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms or An alkoxy cycloalkyl group having 5 to 20 carbon atoms, wherein n is 1 to 3, and X is a cycloheptane including a cyclo group having 4 to 10 carbon atoms, an alkyl group, a cycloalkyl group, an adamantal group, and oxygen Includes a flag.) The method of claim 2,
The sulfonium salt is a composition for forming a photosensitive antireflection film which is a material represented by the following formula (3).
<Formula 3>

The method according to claim 1,
The photosensitive agent is a composition for forming a photosensitive antireflection film comprising at least one of 2,4-isopropyl thioxanthone, benzophenone, and butyl benzyl phthalate. The method according to claim 1,
And the photosensitive agent absorbs the eyeline light to activate an acid generating reaction of the photoacid generator. The method of claim 1, further comprising a polymer resin and a crosslinking agent,
10 to 40% by weight of the polymer resin, 1 to 10% by weight of the photoacid generator, 1 to 10% by weight of the photosensitive agent, and 5 to 20% by weight of the crosslinking agent and an extra solvent. The method according to claim 1,
The eye line light is 365nm light composition for forming a photosensitive antireflection film. Forming a photosensitive antireflection film by coating a composition for forming a photosensitive antireflection film comprising a first photoacid generator including an onium salt and a photoresist that reacts with i-line light on the etching target film;
Forming a photoresist film on the photosensitive antireflection film,
Irradiating eye line light to simultaneously expose the photoresist film and the photosensitive antireflection film,
Developing the exposed photoresist film and the photosensitive antireflection film to form a photosensitive antireflection film pattern and a photoresist pattern,
Patterning the etched film using the photoresist pattern as an etching mask. The method of claim 8,
And the photoresist film comprises a second photoacid generator different from the first photoacid generator of the photosensitive antireflection film. Providing a substrate,
Forming an etching target film on the substrate,
Forming a photosensitive antireflection film by coating a composition for forming a photosensitive antireflection film comprising a first photoacid generator including an onium salt and a photoresist that reacts with i-line light on the etched film,
Forming a photoresist film on the photosensitive antireflection film,
Irradiating eye line light to simultaneously expose the photoresist film and the photosensitive antireflection film,
Developing the exposed photoresist film and the photosensitive antireflection film to form a photosensitive antireflection film pattern and a photoresist pattern,
And forming an etched pattern on the substrate by patterning the etched layer using the photoresist pattern as an etch mask.

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