KR20200021389A - Insulation layer etchant composition and method of forming pattern using the same - Google Patents

Abstract

The present invention relates to an insulating film etchant composition comprising: a first silane compound including two or more alkyl groups containing phosphoric acid, a methyl group or an ethyl group and a silane compound substituted with a passivation group; a second silane compound including a silane compound in which all the substitution sites of silicon atom are substituted with the passivation groups; and extra water. A silicon oxide film can be effectively passivated, and the gelation phenomenon can be effectively suppressed.

Description

INSULATION LAYER ETCHANT COMPOSITION AND METHOD OF FORMING PATTERN USING THE SAME}

The present invention relates to an insulating film etching liquid composition and a pattern forming method using the same. More specifically, the present invention relates to an inorganic acid-based insulating film etching solution composition and a pattern forming method using the same.

For example, a thin film transistor (TFT) and various pixel circuits are arranged on a back-plane substrate of an image display device such as a liquid crystal display (LCD) device or an organic light emitting display (OLED) display device. Insulation layers such as an interlayer insulating film, a gate insulating film, a via insulating film, and the like that insulate the conductive structures are formed.

Further, in a semiconductor device such as a memory device, for example, insulating films such as an element isolation film, an interlayer insulating film, a gate insulating film, and the like are formed on a silicon or germanium substrate.

For example, the insulating layers may be deposited to include silicon oxide or silicon nitride to include a silicon oxide layer and a silicon nitride layer.

When the insulating layer is etched to form an insulation pattern, etching may be selectively performed on a specific layer. For example, a selective etching process for the silicon nitride film may be required. In this case, an etchant composition for etching only the silicon nitride film may be used while sufficiently protecting the silicon oxide film.

In addition, even when the selective etching process is performed for a long time under high temperature conditions, it is preferable that the protection performance of the silicon oxide film is continuously maintained.

For example, Korean Patent Publication No. 10-0823461 discloses a composition capable of etching a silicon oxide film and a silicon nitride film together. It is difficult to implement the above-described selective etching process.

Korea Patent Publication No. 10-0823461

One object of the present invention is to provide an insulating film etchant composition having improved etching selectivity and etching uniformity.

One object of the present invention is to provide a pattern forming method using the insulating film etching solution composition.

1. phosphoric acid; A first silane compound including a silane compound in which two or more alkyl groups including a methyl group or an ethyl group and a passivation group are substituted; A second silane compound comprising a silane compound in which all of the substitution sites of the silicon atoms are all substituted with a passivation group; And excess water.

2. In the above 1, wherein the passivation group including at least one selected from the group consisting of halogen atoms, hydroxy groups, alkoxy groups, acetoxy groups and amine groups other than fluorine, insulating film etching liquid composition.

3. In the above 1, wherein the first silane compound comprises a silane compound represented by any one of the following formulas 1 to 3, insulating film etching solution composition:

[Formula 1]

(In formula 1, R <^1> -R <^3> is respectively independently a methyl group or an ethyl group, n is an integer of 1 or 2, and when n is 1, X <^1> is a halogen element except a fluorine, and an alkoxy group of 1-4 carbon atoms. Or an acetoxy group and when n is 2, X ¹ is a secondary amine group)

[Formula 2]

(In Formula 2, R <^4> and R <^5> is respectively independently a methyl group or an ethyl group, X <^2> and X <^3> are each independently a halogen element except a fluorine, the alkoxy group or the acetoxy group of C1-C4.

[Formula 3]

(In Formula 3, R <^6> and R <^7> is respectively independently a methyl group or an ethyl group, n is an integer of 3-8.

4. The method of 1 above, wherein the silane compound of the fully substituted silane compound comprises a monopodal silane compound or a dipodal silane compound, insulating film etching solution composition.

5. In the above 1, wherein the second silane compound comprises a compound represented by the following formula 4 or 5, insulating film etching liquid composition:

[Formula 4]

(In Formula 4, X ⁴ to X ⁷ are each independently a halogen element except fluorine, an alkoxy group having 1 to 4 carbon atoms, or an acetoxy group.)

[Formula 5]

(In formula 5, X <^9> -X <^14> is respectively independently a halogen element except fluorine, the alkoxy group of C1-C4, an acetoxy group, or a phosphoric acid group, and Y is a C1-C4 alkylene group. "

6. In the above 1, wherein the second silane compound and the first silane compound is contained in a weight ratio of 1: 1 to 1:50, the insulating film etchant composition.

7. In the above 1, wherein the second silane compound and the first silane compound is included in a weight ratio of 1: 4 to 1:30, insulating film etching solution composition.

8. according to the above 1, the second silane compound is contained in an amount of 0.01 to 1% by weight, the first silane compound is contained in an amount of 0.1 to 10% by weight, the insulating film etching liquid composition.

9. forming an oxide film and a nitride film on the substrate; And selectively etching the nitride film using the insulating film etchant composition of any one of 1 to 8 above.

10. The method according to 9 above, wherein the oxide film includes silicon oxide and the nitride film includes silicon nitride.

In the insulating film etching solution composition according to the embodiments of the present invention, the second silane compound and the first silane compound are used together. Therefore, it is possible to prevent the gelation of the etchant with an excellent passivation effect.

In addition, the second silane compound and the first silane compound may be substantially completely dissolved in an aqueous solution of phosphoric acid, and may be excellent in phosphoric acid compatibility.

In addition, even when the nitride film is repeatedly treated with the etchant, the etching performance of the etchant can be prevented from being lowered.

The insulating film etching composition according to the exemplary embodiments may be effectively used in the selective etching process of the nitride film to etch the silicon nitride film while suppressing the etching of the silicon oxide film.

1 to 3 are schematic cross-sectional views for describing a method of forming a pattern according to example embodiments.
4 to 6 are schematic cross-sectional views for describing a method of forming a pattern according to example embodiments.

The insulating film etchant composition of embodiments of the present invention includes phosphoric acid, a first silane compound, a second silane compound, and excess water. The silicon oxide film can be passivated effectively, and the gelation phenomenon can be effectively suppressed. In addition, it provides a pattern forming method using the etchant composition.

Hereinafter, embodiments of the present invention will be described in detail.

<Insulation film Etching  Composition>

According to exemplary embodiments, the insulating film etching composition may include phosphoric acid, a first silane compound including a passivation group in a silicon atom, and a silane compound in which two or more alkyl groups are substituted, and all substitution sites of the silicon atom are substituted with a passivation group. A second silane compound, including excess silane compound, and excess water.

The insulating film etching composition is supplied onto a structure including an oxide film (eg, silicon oxide film) and a nitride film (eg, silicon nitride film) at the same time to etch only the nitride film at a high selectivity without substantially damaging the oxide film. Can be used for

For example, the insulating film etching composition may be used to selectively etch the silicon nitride film in the manufacturing process of the semiconductor device.

Phosphoric acid may be represented, for example, by the chemical formula of H ₃ PO ₄ , and may serve as a main etching component for nitride film etching. In example embodiments, the insulating film etching composition may include about 80 to about 95 wt% of phosphoric acid by weight percent of the total weight of the composition.

If the content of phosphoric acid is less than about 80% by weight, the overall etching rate may be lowered. When the content of phosphoric acid exceeds about 95% by weight, the etching rate of not only the nitride film but also the conductive film such as the oxide film or the metal film may increase together, thereby reducing the etching selectivity of the nitride film.

Preferably, the phosphoric acid content may be adjusted to about 80 to 90% by weight in consideration of the etching rate and the selectivity.

The first silane compound may include a silane compound in which two or more alkyl groups including a methyl group or an ethyl group and a passivation group are substituted. The first silane compound is excellent in phosphoric acid compatibility and can effectively inhibit the gelation phenomenon. In addition, the oxide film may be passivated to protect it in an etching process. The said 1st silane compound can suppress the gelation phenomenon of a 2nd silane compound.

As used herein, the term "phosphate compatibility" means that the silane compound is substantially homogeneously dissolved in the aqueous solution of phosphoric acid, and does not readily produce siloxane compound particles by gelation. For example, 1 g of a silane compound is added to 100 g of an aqueous 85% phosphoric acid solution, and after stirring for 1 minute at room temperature, it can be evaluated by the phase separation when left at room temperature for 1 minute.

The silane compound may mean a compound in which hydrogen or substituents are connected to the silicon atom using a silicon atom as a center atom. The silicon atom may have four bonding sites. Thus, up to three alkyl groups may be substituted.

The first silane compound may be a compound in which a passivation group and two or more alkyl groups are directly connected to the silicon atom. For example, it may be a compound in which one passivation group and three alkyl groups are directly connected to the silicon atom, and may be a compound in which two passivation groups and two alkyl groups are directly connected to the silicon atom.

In some embodiments, the passivation group may include at least one selected from the group consisting of halogen atoms, hydroxy groups, alkoxy groups, acetoxy (-OAc) groups, and amine groups other than fluorine. The passivation group may passivate the silicon oxide layer to protect the passivation layer from being etched in the etching process. For example, the passivation group may be hydrolyzed in an aqueous solution of phosphoric acid to dissociate into a silanol group (Si-OH). In other words, halogen atoms other than fluorine, hydroxy groups, alkoxy groups, acetoxy groups and amine groups can be hydrolyzed to dissociate into silanol groups. The silanol group may passivate the silicon oxide film.

The silanol group may be condensed with a silanol group of an adjacent silane compound to form a polymer. The condensation reaction may cause gelation of the etchant composition. However, as the first silane compound is substituted with two or more alkyl groups, the number of silanol groups is limited to two or less, so that the condensation reaction may be limited. Thus, gelation can be effectively suppressed.

In addition, when the first silane compound is condensed with the second silane compound, the first condensation reaction of the second silane compound may be stopped. For example, the first silane compound may be used as an end-capping agent of the second silane compound. Therefore, gelation of the entire second silane compound and the etchant composition can be prevented.

In the comparative example, when fluorine is used as the passivation group, the silicon oxide film may be etched. Therefore, the nitride film etching selectivity of the etchant composition may be reduced.

In a similar aspect, in some embodiments, the insulating film etching composition may not include a fluorine-containing compound. Thereby, etching damage of the oxide film (for example, silicon oxide film) by the fluorine component can be prevented. Therefore, the nitride film etching selectivity can be improved. For example, the composition according to the exemplary embodiments of the present invention may be a non-fluorine-based insulating film etchant composition.

According to some embodiments, the alkyl group may include a methyl group or an ethyl group. Thus, the first silane compound may be dissolved in an aqueous solution of phosphoric acid.

In the comparative example, when an alkyl group having 3 or more carbon atoms such as a propyl group is used as the alkyl group, the solubility of the first silane compound in an aqueous solution of phosphoric acid may be significantly reduced, and the passivation effect and gelling inhibition property of the etchant composition may be significantly reduced. Can be.

In example embodiments, the first silane compound may include a silane compound represented by any one of Formulas 1 to 3 below. The silane compound represented by any one of Formulas 1 to 3 may be provided as a silane compound in which a passivation group and two or more alkyl groups are substituted on the silicon atom.

[Formula 1]

In Formula 1, R ¹ to R ³ are each independently a methyl group or an ethyl group, n is an integer of 1 or 2, when n is 1, X ¹ is a halogen element except fluorine, an alkoxy group having 1 to 4 carbon atoms or When n is 2, X ¹ may be a secondary amine group.

[Formula 2]

In Formula 2, R ⁴ and R ⁵ are each independently a methyl group or an ethyl group, and X ² and X ³ may each independently be a halogen element except for fluorine, an alkoxy group having 1 to 4 carbon atoms, or an acetoxy group.

[Formula 3]

In Formula 3, R ⁶ and R ⁷ are each independently a methyl group or an ethyl group, n may be an integer of 3 to 8.

The compounds represented by Chemical Formulas 1 to 3 may be used alone, or two or more thereof may be mixed and used.

The compounds represented by Chemical Formulas 1 to 3 include two or three alkyl groups, and the alkyl group may be a methyl group or an ethyl group. Thus, it can be effectively dissolved in the aqueous solution of phosphoric acid, the condensation reaction is limited and the gelation phenomenon can be suppressed.

In addition, a passivation group may be used to passivate the silicon oxide film. The passivation group can be dissociated with a silanol group and can block the continuous condensation reaction of the second silane compound. Therefore, gelation of the entire second silane compound and the etchant composition can be prevented.

The compound represented by Chemical Formula 1 may include, for example, at least one of the compounds represented by the following Chemical Formulas 1-1 to 1-3.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

The compound represented by Chemical Formula 2 may include, for example, at least one of the compounds represented by the following Chemical Formulas 2-1 to 2-3.

[Formula 2-1]

[Formula 2-2]

[Formula 2-3]

The compound represented by Chemical Formula 3 may include, for example, a compound represented by Chemical Formula 3-1.

[Formula 3-1]

The second silane compound includes a silane compound in which all the substitution sites of the silicon atoms are substituted with passivation groups. The second silane compound may exhibit an excellent oxide protective effect by a plurality of passivation groups. In addition, while being used together with the first silane compound greatly improves the oxide film protection effect, the gelation phenomenon can be prevented.

The substitution site may mean a site which may be substituted with a substituent among the bonding sites of the silicon atoms. That is, the silane compound in which all the substitution sites of the silicon atom are substituted with the passivation group may mean a compound in which all the sites that can be substituted with the substituent among all the bonding sites of the silicon atom are substituted with the passivation group. Thus, the second silane compound may provide a good passivation effect by having a plurality of passivation groups.

According to some embodiments, the silane compound of the fully substituted silane compound may include a monopodal silane compound or a dipodal silane compound. The monopodal compound may refer to a compound containing one silicon atom. The dipodal compound may mean a compound including two silicon atoms. The two silicon atoms may be connected to each other by a linker group.

For example, in the monopodal silane compound, all four bonding sites of the silicon atom are substituted sites, and all four substituted sites may be substituted with passivation groups. In the dipodal silane compound, a total of six bonding sites may be substituted sites except for bonding sites connecting silicon atoms to each other out of eight bonding sites of two silicon atoms, and all six substitution sites are passivation groups. Can be substituted. The dipodal silane compound may include more passivation groups in one molecule and passivation groups each connected to two silicon atoms may protect, for example, an oxide film. Thus, the passivation effect can be better.

In some embodiments, the second silane compound may include a compound represented by Formula 4 or 5 below. The compound represented by the following Chemical Formula 4 or 5 may be provided as a silane compound in which all substitution sites of the silicon atom are substituted with a passivation group.

[Formula 4]

In Formula 4, X ⁴ to X ⁷ may be each independently a halogen element except fluorine, an alkoxy group having 1 to 4 carbon atoms, or an acetoxy group.

[Formula 5]

In Formula 5, X ⁹ to X ¹⁴ are each independently a halogen element except fluorine, an alkoxy group having 1 to 4 carbon atoms, or an acetoxy group, and Y may be an alkylene group having 1 to 3 carbon atoms.

In the comparative example, when Y is an alkylene group having 5 or more carbon atoms such as a pentylene group, the compound of Formula 5 may not be substantially dissolved in the aqueous solution of phosphoric acid. Therefore, the passivation effect of the etchant composition can be greatly reduced.

Each of the compounds represented by Formula 4 or 5 may be used alone, or two kinds thereof may be mixed and used.

The compound represented by Formula 4 may be substituted with four passivation groups as a monopodal silane compound, thereby exhibiting an excellent passivation effect.

The compound represented by Chemical Formula 4 may include, for example, at least one of the compounds represented by the following Chemical Formulas 4-1 to 4-3.

[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

The compound represented by Chemical Formula 5 may be substituted with six passivation groups as a dipodal silane compound, thereby exhibiting an excellent passivation effect.

The compound represented by Chemical Formula 5 may include, for example, at least one of the compounds represented by the following Chemical Formulas 5-1 to 5-4.

[Formula 5-1]

[Formula 5-2]

[Formula 5-3]

[Formula 5-4]

The second silane compound may include a plurality of passivation groups, and the plurality of passivation groups may be dissociated into silanol groups in an aqueous solution of phosphoric acid. Therefore, a plurality of silanol groups may be formed, and the silanol groups may form a siloxane compound through a continuous condensation reaction. In particular, the condensation reaction occurs three-dimensionally, the molecular weight of the siloxane compound is rapidly increased, the gelation may be intensified. However, by using together the said 1st silane compound, the said 1st silane compound can suppress the polymerization reaction of the said 2nd silane compound. Therefore, the gelation phenomenon can be prevented while securing an excellent passivation effect.

In exemplary embodiments, the second silane compound and the first silane compound may be used in a weight ratio of 1: 1 to 1:50. For example, the first silane compound may be used in excess (by weight) than the second silane compound. In the weight ratio range, the excellent passivation effect of the second silane compound, the phosphoric acid compatibility of the first silane compound, and the anti-gelling effect may be simultaneously obtained. More preferably, the second silane compound and the first silane compound may be used in a weight ratio of 1: 4 to 1:30.

In some embodiments, the first silane compound may be used in an amount of 0.1 to 10% by weight based on the total weight of the composition. When the content is less than the above, the phosphoric acid compatibility improvement and anti-gelling effect may not be sufficiently implemented. When the content exceeds the content, the first silane compound may not be completely dissolved in the aqueous solution of phosphoric acid, and gelation of the first silane compound itself may be promoted. In addition, the action of phosphoric acid may be hindered to reduce the etching performance of the composition.

According to exemplary embodiments, 0.01 to 1% by weight of the second silane compound may be used based on the total weight of the composition. When the content of the second silane compound is less than 0.01% by weight based on the total weight of the composition, the passivation effect may be insufficient, and when the content is more than 1% by weight based on the total weight of the composition, gelation may be promoted.

In some embodiments, the insulating film etching composition may not include a component capable of generating a residue in the etching object, for example, an oxime compound. Accordingly, the silicon nitride film etching efficiency by phosphoric acid may be improved while protecting the silicon oxide film by the first silane compound and the second silane compound.

The insulating film etching composition may include excess water (eg, deionized water). For example, the phosphoric acid may be provided in the form of an aqueous solution (eg, 85% phosphoric acid), and the first silane compound and the second silane compound may be mixed in the amounts described above with respect to 100 parts by weight of the aqueous solution of phosphoric acid.

In some embodiments, the insulating film etching composition may be substantially composed of the above-described phosphoric acid, the first silane compound, the second silane compound, and excess water. In some embodiments, the insulating film etching composition may include additional components such as an etch enhancer within a range that does not impair passivation performance, etch efficiency and anti-gelling properties of the first and second silane compounds. It may be.

<Pattern forming method>

1 to 3 are schematic cross-sectional views for describing a method of forming a pattern according to example embodiments.

Referring to FIG. 1, the oxide film 110 and the nitride film 120 may be sequentially formed on the substrate 100.

The substrate 100 may include a semiconductor material such as single crystal silicon, single crystal germanium, or may be formed to include polysilicon.

According to example embodiments, the oxide film 110 may be formed to include silicon oxide. The oxide film 110 may be formed through a chemical vapor deposition (CVD) process, a sputtering process, a physical vapor deposition (PVD) process, an atomic layer deposition (ALD) process, or the like.

The nitride film 130 may be formed on the oxide film 110. In example embodiments, the nitride layer 130 may be formed through a CVD process, a PVD process, a sputtering process, an ALD process, and the like to include silicon nitride.

Referring to FIG. 2, a photoresist pattern 130 may be formed on the nitride film 120. For example, after the photoresist film is formed on the nitride film 120, a portion of the photoresist film may be removed through a selective exposure process and a developing process.

Accordingly, the photoresist pattern 130 exposing a part of the upper surface of the nitride film 120 may be formed.

Referring to FIG. 3, a wet etching process using the photoresist pattern 130 as an etching mask and using an insulating film etchant composition according to the exemplary embodiments described above may be performed.

Accordingly, the exposed nitride layer 120 may be removed to form the nitride layer pattern 125. As described above, the insulating film etchant composition according to the exemplary embodiments may provide significantly improved oxide passivation by the first silane compound and the second silane compound, while suppressing regrowth of the oxide film. Accordingly, the surface of the oxide film 110 may be substantially etched or damaged, or regrowth may not occur, and only the nitride film 120 may be selectively etched.

For the efficiency of the etching process, the temperature of the etchant composition may be heated to about 150 ℃ or more. Since the first silane compound and the second silane compound are stable even at a high temperature, the initial etching rate and the passivation performance can be maintained uniformly.

The photoresist pattern 130 may then be removed through a strip process and / or an ashing process.

As shown in FIGS. 1 to 3, the nitride film 120 may be partially etched, but the nitride film 120 may be entirely removed using the etchant composition. Even in this case, the entire upper surface of the oxide film 110 may be passivated entirely by the first silane compound and the second silane compound to be protected from etching damage.

4 to 6 are schematic cross-sectional views for describing a method of forming a pattern according to example embodiments.

Referring to FIG. 4, the plurality of oxide films 210 and the plurality of nitride films 220 may be alternately repeatedly stacked on the substrate 200.

Referring to FIG. 5, a through pattern 230 penetrating the oxide films 210 and the nitride films 220 may be formed. For example, after the oxide layers 210 and the nitride layers 220 are etched together through dry etching to form an opening, the through pattern 230 may be formed by filling a filling material in the openings. The through pattern 230 may include a semiconductor material such as polysilicon or a conductive material such as a metal.

Referring to FIG. 6, the nitride layers 220 may be selectively removed using the etchant composition according to the exemplary embodiments described above.

Accordingly, the oxide layers 210 may remain on the sidewall of the through pattern 230, and the gaps 240 may be defined by the space from which the nitride layers 220 are removed. The gaps 240 may be filled with a conductive film, for example, a metal film. The oxide layers 210 may be passivated entirely by the first silane compound and the second silane compound during the etching process to be protected from etching damage and to maintain thickness and shape.

The above-described pattern forming method is exemplary, and the insulating film etching composition according to the embodiments of the present invention may be used to form various insulating structures (eg, gate insulating film, barrier film, device isolation film, etc.) included in a semiconductor device or a display device. Can be applied for

Hereinafter, experimental examples including specific examples and comparative examples are provided to help the understanding of the present invention, but these are merely illustrative of the present invention and are not intended to limit the appended claims, and the scope and spirit of the present invention. It is apparent to those skilled in the art that various changes and modifications to the embodiments can be made within the scope, and such variations and modifications are within the scope of the appended claims.

Example  And Comparative example

To the aqueous solution of 85% phosphoric acid was prepared by mixing the silane compound of Table 1 in the content of Table 1 (% by weight relative to the total weight of the composition). A portion of the total weight of the composition except for the following silane compound is accounted for by an aqueous 85% phosphoric acid solution. In the formulas below, OEt means ethoxy.

For the compounds of Formulas 1-1 to 5-4, the compounds described above were used, and the following compounds were used for the compounds of Formula 6.

[Formula 6]

division Secondary silane compound First silane compound Other Kinds content Kinds content Kinds content Example 1 Formula 4-1 0.1 Formula 1-1 One - - Example 2 Formula 4-1 0.1 Formula 1-3 One - - Example 3 Formula 4-1 0.1 Formula 2-1 One - - Example 4 Formula 4-1 0.1 Formula 3-1 One - - Example 5 Formula 4-1 0.1 Formula 1-1 0.1 - - Example 6 Formula 4-1 0.1 Formula 1-1 0.2 - - Example 7 Formula 4-1 0.1 Formula 1-1 0.4 - - Example 8 Formula 5-1 0.02 Formula 1-1 0.08 - - Example 9 Formula 5-1 0.02 Formula 1-1 0.2 - - Example 10 Formula 5-1 0.02 Formula 1-1 0.6 - - Example 11 Formula 5-1 0.02 Formula 1-1 One - - Example 12 Formula 5-1 0.02 Formula 2-1 0.2 - - Example 13 Formula 5-4 0.02 Formula 1-1 0.2 - - Comparative Example 1 Formula 4-1 0.1 - - - - Comparative Example 2 Formula 5-1 0.02 - - - - Comparative Example 3 - - Formula 1-1 One - - Comparative Example 4 - - - - Formula 6 One

Experimental Example

(One) Gelation  Prevention rating

1 g of the silane compound of Examples and Comparative Examples was added to 100 g of an aqueous 85% phosphoric acid solution, and then stirred for 1 minute at room temperature, and then evaluated for phase separation (gelling) when left at room temperature for 1 minute.

○: not gelated

Δ: instantaneously gelled and then dissolved again

Ｘ: does not dissolve again after gelling

(2) silicon oxide film ( SiO ₂ ) Etching  Suppression assessment

A silicon oxide film (SiO ₂ ) 400 mm thick wafer was cut into a size of ² × ² cm ² to prepare a sample, and the sample was immersed in the compositions of Examples and Comparative Examples described in Table 2 at a temperature of 160 ° C. for 3600 seconds. Then, after washing and drying with deionized water (DIW), by measuring the film thickness before and after etching with an ellipsometer (Elipsometer) to measure the amount of etching and evaluated according to the following criteria.

◎: 6 Hz or less

○: more than 6 Å 12 Å or less

(Triangle | delta): More than 12 Hz and less than 25 Hz

×: more than 25 mm

(3) Silicon according to the number of treatment Nitride of SiN Etching  Speed change evaluation

A sample was prepared by cutting a silicon nitride film (SiN) 5000 mm thick wafer into a size of ² × ² cm ² , and the sample was immersed in the compositions of Examples and Comparative Examples at a temperature of 160 ° C. for 3 minutes. Then, after washing and drying with deionized water (DIW), the film thickness was measured with a scanning electron microscope (SEM) to measure the initial etching rate (속도 / min).

Ten silicon nitride film samples were removed by immersing the composition of Examples and Comparative Examples at a temperature of 160 ° C. for 1 hour to remove all of the silicon nitride film (SiN) etching rate after treatment of 10 sheets. R) was remeasured and evaluated according to the following criteria.

○: Etching speed after initial processing of 10 sheets

(Triangle | delta): Etch rate / initial etching rate 0.8 or more and 0.9 or less after 10 sheets process

×: etching rate after initial processing of 10 sheets / initial etching rate of less than 0.8

The evaluation results are shown in Table 2 below.

Gelation prevention Silicon Oxide Etch Suppression Changes in SiN Etch Rate According to Number of Treated Sheets Example 1 ○ ○ ○ Example 2 ○ ○ ○ Example 3 ○ ○ ○ Example 4 ○ ○ ○ Example 5 △ ○ △ Example 6 △ ○ △ Example 7 ○ ○ △ Example 8 △ ◎ △ Example 9 ○ ◎ ○ Example 10 ○ ◎ △ Example 11 ○ ◎ △ Example 12 ○ ◎ ○ Example 13 ○ ◎ ○ Comparative Example 1 × ○ × Comparative Example 2 × ◎ × Comparative Example 3 ○ × × Comparative Example 4 △ △ △

Referring to Table 2, in the examples in which the second silane compound and the first silane compound were used together, the anti-gelling property and the passivation effect were excellent, and the etching rate according to the number of nitride film treatments was small.

In Comparative Examples 1 and 2, the gelation phenomenon was particularly severe because no first silane compound was used.

In Comparative Example 3, the passivation effect of the oxide film was inferior by using the first silane compound alone.

100, 200: substrate 110, 210: oxide film
120 and 220: nitride film 130: photoresist pattern
230: through pattern

Claims (10)

Phosphoric acid;
A first silane compound including a silane compound in which two or more alkyl groups including a methyl group or an ethyl group and a passivation group are substituted;
A second silane compound comprising a silane compound in which all of the substitution sites of the silicon atoms are all substituted with a passivation group; And
An insulating film etching liquid composition comprising excess water.
The insulating film etchant composition of claim 1, wherein the passivation group includes at least one selected from the group consisting of halogen atoms, hydroxy groups, alkoxy groups, acetoxy groups, and amine groups except fluorine.
The insulating film etching liquid composition of claim 1, wherein the first silane compound comprises a silane compound represented by any one of Formulas 1 to 3 below:
[Formula 1]

(In formula 1, R <^1> -R <^3> is respectively independently a methyl group or an ethyl group, n is an integer of 1 or 2, and when n is 1, X <^1> is a halogen element except a fluorine, and an alkoxy group of 1-4 carbon atoms. Or an acetoxy group and when n is 2, X ¹ is a secondary amine group)
[Formula 2]

(In Formula 2, R <^4> and R <^5> is respectively independently a methyl group or an ethyl group, X <^2> and X <^3> are each independently a halogen element except a fluorine, the alkoxy group or the acetoxy group of C1-C4.
[Formula 3]

(In Formula 3, R <^6> and R <^7> is respectively independently a methyl group or an ethyl group, n is an integer of 3-8.
The insulating film etchant composition of claim 1, wherein the silane compound of the fully substituted silane compound comprises a monopodal silane compound or a dipodal silane compound.
The method of claim 1, wherein the second silane compound comprises a compound represented by the following formula 4 or 5, insulating film etching liquid composition:
[Formula 4]

(In Formula 4, X ⁴ to X ⁷ are each independently a halogen element except fluorine, an alkoxy group having 1 to 4 carbon atoms, or an acetoxy group.)
[Formula 5]

(In formula 5, X <^9> -X <^14> is respectively independently a halogen element except fluorine, the alkoxy group of C1-C4, an acetoxy group, or a phosphoric acid group, and Y is a C1-C4 alkylene group. "
The insulating film etching liquid composition of claim 1, wherein the second silane compound and the first silane compound are included in a weight ratio of 1: 1 to 1:50.
The insulating film etchant composition of claim 1, wherein the second silane compound and the first silane compound are included in a weight ratio of 1: 4 to 1:30.
The insulating film etchant composition of claim 1, wherein the second silane compound is present in an amount of 0.01 to 1% by weight, and the first silane compound is included in an amount of 0.1 to 10% by weight.
Forming an oxide film and a nitride film on the substrate; And
Selectively etching the nitride film using the insulating film etchant composition according to any one of claims 1 to 8.
The method of claim 9, wherein the oxide film comprises silicon oxide and the nitride film comprises silicon nitride.

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