KR20200080835A - Etching composition, method for etching insulating layer of semiconductor devices using the same and method for preparing semiconductor devices - Google Patents

Abstract

The present invention provides an etching composition capable of improving element properties by preventing deterioration of electrical properties and preventing particles from being generated, and the etching composition according to one embodiment of the present invention includes: a phosphoric acid; and a silane compound represented by Formula 1 as follows. In Formula 1, R_1 to R_6 are independently hydrogen, hydrocarbyl, or non-hydrocarbyl, at least one pair among R^1 and R^2, R^3 and R^4, and R^5 and R^6 form a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group connected to each other, L_p is hydrocarbylene, p is 0 or 1, A is an n-valent radical, and n is an integer of 1 to 4.

Description

Etching composition, etching method of insulating film using the same, and manufacturing method of semiconductor device {ETCHING COMPOSITION, METHOD FOR ETCHING INSULATING LAYER OF SEMICONDUCTOR DEVICES USING THE SAME AND METHOD FOR PREPARING SEMICONDUCTOR DEVICES}

The present invention relates to an etching composition having a high selectivity, which can selectively remove the nitride film while minimizing the etching rate of the etching composition, particularly the oxide film.

An oxide film such as a silicon oxide film (SiO ₂ ) and a nitride film such as a silicon nitride film (SiNx) are typical insulating films. In the semiconductor manufacturing process, each of these silicon oxide films or silicon nitride films alone or one or more layers are alternately stacked and used. Further, these oxide films and nitride films are also used as hard masks for forming conductive patterns such as metal wiring.

In the wet etching process for removing the nitride film, a mixture of phosphoric acid and deionized water is generally used. Deionized water is added to prevent an etch rate decrease and change in etching selectivity to the oxide film, but there is a problem in that a defect occurs in the nitride film etch removal process even with a small change in the amount of deionized water supplied. In addition, phosphoric acid is a strong acid and has corrosive properties, which makes handling difficult.

As a conventional technique for solving this, a method of removing a nitride film using an etching composition containing hydrofluoric acid (HF) or nitric acid (HNO ₃ ) in phosphoric acid (H ₃ PO ₄ ) is known, but rather, etching of the nitride film and the oxide film is selected. This resulted in the inhibition of rain. In addition, although a technique using an etch composition containing phosphoric acid and silicate or silicic acid is also known, silicic acid or silicate causes particles that may affect the substrate, which is rather unsuitable for semiconductor manufacturing processes.

However, when using phosphoric acid in the wet etching process for removing the nitride film, it is difficult to control the effective field oxide height (EFH) by etching not only the nitride film but also the SOD oxide film due to a decrease in the etching selectivity between the nitride film and the oxide film. Lose. Accordingly, sufficient wet etching time for removing the nitride film may not be secured, or an additional process may be required, causing a change, which adversely affects device characteristics.

Therefore, in a semiconductor manufacturing process, an etching composition having a high selectivity ratio that selectively etches a nitride film with respect to an oxide film but does not have a problem such as particle generation is required.

On the other hand, the silane-based additive, which is an additive added to the conventional etching composition, has low solubility, so that proper solubility is not secured, thereby causing particles to precipitate in the etching composition and abnormal growth of the substrate. Such particles remain on the silicon substrate and cause defects of devices implemented on the substrate, or remain in equipment used in an etching or cleaning process to cause equipment failure.

Furthermore, when the etchant is stored for a long time, the etching rate of the nitride film and the silicon oxide film is changed, so the selectivity may be changed.

An object of the present invention is to provide a high selectivity etch composition that can selectively remove the nitride film while minimizing the etch rate of the oxide film and does not have problems such as particle generation that adversely affects device characteristics.

Furthermore, it is intended to provide an etching method of an insulating film using the etching composition and a method of manufacturing a semiconductor device.

The present invention is intended to provide an etch composition, and according to an embodiment of the present invention, provides an etch composition comprising phosphoric acid and a silane compound represented by Formula 1 below.

[Formula 1]

In Formula 1, R ¹ to R ⁶ are independently hydrogen, hydrocarbyl, or non-hydrocarbyl, R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ At least one pair forms a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group, L _p is hydrocarbylene, p is 0 or 1, A is an n-valent radical, and n is 1 It is an integer of 4-4.

At least one pair of R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ^{6 may} be a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group, and the rest may be hydrogen.

It is more preferable that L _p is C1-C5 alkylene, and p is 1.

The A may be hydrogen, halogen, tri(C1-C20)alkylsilyl, hydrocarbylene, a radical having a bonding site of N, a radical having a bonding site of O, a radical having a bonding site of S, or a radical having a bonding site of P .

The hydrocarbylene may be C1-C20 alkyl, C2-C20 alkenyl or C6-C20 aryl.

일 수 있으며, 여기서, R¹¹ 및 R¹²는 독립적으로 수소, C1-C20알킬, C1-C20아미노알킬 또는 CONH₂이고, R¹³ 내지 R¹⁷은 독립적으로 수소 또는 C1-C20알킬이며, L₁은 C1-C20알킬렌이다.The radical in which the bonding site is N is *-NR ¹¹ R ¹² , *-NR ¹³ -*, *-NR ¹⁴ CONR ¹⁵ -*, *-NR ¹⁶ CSNR ¹⁷ -* or

Wherein R ¹¹ and R ¹² are independently hydrogen, C1-C20 alkyl, C1-C20 aminoalkyl or CONH ₂ , R ¹³ to R ¹⁷ are independently hydrogen or C1-C20 alkyl, L ₁ is C1-C20alkylene.

The radical having the bonding site O may be *-O-*.

또는

일 수 있다.The bonding site S is a radical *-S-*, *-SS-*,

or

Can be

,

,

또는

일 수 있으며, 여기서, R¹⁸ 및 R¹⁹는 독립적으로, 수소, C1-C20알킬, C6-C20아릴, 또는 (C1-C20)알킬(C1-C20)알콕시이다.The radical where the binding site is P is

,

,

or

Wherein R ¹⁸ and R ¹⁹ are independently hydrogen, C 1 -C 20 alkyl, C 6 -C 20 aryl, or (C 1 -C 20 )alkyl (C 1 -C 20 )alkoxy.

In Formula 1, n is 1, Lp is C1-C5 alkylene, p is 0 or 1, A is hydrogen, halogen, substituted or unsubstituted C1-C20 alkyl, substituted or unsubstituted C1- C20 alkenyl, *-NH ₂ , *-NH-(CH ₂ ) _l -NH ₂ , *-NH-CO-NH ₂ , or *-(CH ₂ ) _m -C ₆ H ₅ , l and m are It may be an integer from 0 to 10 independently.

,

,

, 또는

이고, R¹³ 내지 R¹⁵, R¹⁸ 및 R¹⁹는 독립적으로 수소, C1-C20알킬, C6-C20아릴, 또는 (C1-C20)알킬(C1-C20)알콕시일 수 있다.In Formula 1, n is 2, Lp is C1-C5 alkylene, p is 0 or 1, A is C1-C20 alkylene, *-NR ¹³ -*, *-NR ¹⁴ -CO-NR ¹⁵ -*, *-O-*, *-S-*, *-SS-*,

,

,

, or

And R ¹³ to R ¹⁵ , R ¹⁸ and R ¹⁹ can be independently hydrogen, C1-C20 alkyl, C6-C20 aryl, or (C1-C20)alkyl(C1-C20)alkoxy.

또는

일 수 있다.In Chemical Formula 1, n is 3, Lp is C1-C5 alkylene, p is 0 or 1, and A is

or

Can be

이고, 여기서 L₁은 C1-C10 알킬렌일 수 있다.In Chemical Formula 1, n is 4, Lp is C1-C5 alkylene, p is 0 or 1, and A is

, Where L ₁ may be C1-C10 alkylene.

The silane compound may be selected from the following structures.

(1),

(2),

(3),

(4),

(5),

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

(One),

(2),

(3),

(4),

(5),

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

The etch composition preferably includes 0.001 to 5% by weight of the silane compound represented by Formula 1, and the etch composition is 70 to 90% by weight of phosphoric acid, 0.001 to 5% by weight of the silane compound represented by Formula 1, and the balance water It may be to include.

The etching composition may further include a silane compound represented by Formula 2 below.

[Formula 2]

In Chemical Formula 2, R ⁵¹ to R ⁵⁴ are independently of each other hydrogen, C1-C20 hydrocarbyl, C1-C20 heterohydrocarbyl, and R ⁵¹ to R ⁵⁴ are each present, or two or more are via hetero elements It is a ring form connected to each other.

The etching composition may further include an ammonium salt.

The present invention provides a method of etching an insulating film using the etching composition as another aspect.

In another aspect, the present invention provides a method of manufacturing a semiconductor device including the etching method of the insulating film.

The present invention also provides a silane compound represented by Formula 1 below.

[Formula 1]

In Formula 1, R ¹ to R ⁶ are independently hydrogen, hydrocarbyl, or non-hydrocarbyl, R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ At least one pair forms a naphthalene group, L _p is C1-C5 hydrocarbylene, p is 0 or 1, A is hydrogen, halogen, tri(C1-C20)alkylsilyl, C1-C20 alkyl, C2 -C20 alkenyl or C6-C20 aryl, n is 1.

Formula 1 may be a silane compound represented by the following structure.

Silane compounds represented by any one of the following structures are also provided.

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

The etching composition according to the present invention has a high etching selectivity of the nitride film to the oxide film.

In addition, when the etching composition of the present invention is used, it is possible to prevent deterioration of electrical properties due to damage to the film quality of the oxide film or etching of the oxide film when removing the nitride film, and to prevent particle generation, thereby improving device characteristics.

1 and 2 are sectional views illustrating a method of etching an insulating film according to an embodiment of the present invention.

The present invention is to provide an etching composition having a high selectivity to selectively remove the nitride film while minimizing the etching rate of the etching composition, particularly the oxide film, and also excellent storage stability.

The etching composition of the present invention includes phosphoric acid, a silane compound and water.

The phosphoric acid reacts with silicon nitride to etch the nitride, and the phosphoric acid reacts as shown in Formula (1) below to etch the silicon nitride.

3Si ₃ N ₄ + 27H ₂ O + 4H ₃ PO ₄ → 4(NH ₄ ) ₃ PO ₄ + 9SiO ₂ H ₂ O (1)

For example, the phosphoric acid may be an aqueous phosphoric acid solution containing phosphoric acid at a concentration of 75 to 85%. The water used in the aqueous phosphoric acid solution is not particularly limited, but deionized water may be used.

The phosphoric acid is preferably included in an amount of 70 to 90% by weight relative to the total weight of the etching composition. If it is less than 70% by weight, there is a problem that the nitride film is not easily removed, and when it exceeds 90% by weight, a high selectivity for the nitride film cannot be obtained.

The etching composition of the present invention includes a silane compound as an etching solution additive. The silane compound may be, for example, a silane compound represented by Formula 1 below.

In Formula 1, R ¹ to R ⁶ are independently hydrogen, hydrocarbyl, or non-hydrocarbyl, R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ At least one pair may be to form a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group. When at least one pair of R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ is a substituted or unsubstituted aryl group or cycloalkyl group, the hydrolysis resistance of the silane compound increases to increase the corrosion resistance of the composition. It can be kept stable for a long time.

The hydrocarbyl or non-hydrocarbyl is halogen; Substituted or unsubstituted C1-C20 hydrocarbyl group, C1-C20 alkoxy group, carboxyl group, carbonyl group, nitro group, tri(), such as substituted or unsubstituted C1-C20 alkyl group, phenyl group or substituted or unsubstituted C6-C20 aryl group. C1-C20) alkyl silyl group, phosphoryl group or cyano group. In addition, the substitution may be a hydrocarbyl group is substituted with a halogen such as halogenated alkyl.

More preferably, R ¹ and R ² , R ³ and R ⁴ and at least one pair of R ⁵ and R ⁶ are a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group, and the rest may be hydrogen. have.

The Lp is L _p is a hydrocarbylene, p is 0 or 1, the Lp may be a direct bond, or C1-C5 hydrocarbylene, more specifically C1-C5 alkylene, for example C1 -C3 alkylene.

The A represents an n-valent radical that is an integer from 1 to 4. For example, A is hydrogen, halogen, tri(C1-C20)alkylsilyl, hydrocarbylene, a radical having a binding site of N, a radical having a binding site O, a radical having a binding site S, a radical having a binding site P Etc.

For example, A may be hydrogen, and may be halogen such as F, Cl, Br, I, or trialkylsilyl such as -Si(CH ₃ ) ₃ . At this time, n is an integer of 1.

The hydrocarbylene may be substituted or unsubstituted C1-C20 alkyl, C2-C20 alkenyl or C6-C20 aryl, and more specifically, -CH ₃ , -(CH ₂ ) ₃ ,- (CH ₂ ) ₂ CH ₃ , -(CH ₂ ) ₇ CH ₃ , -CH ₂ CH(CH ₃ ) ₂ , -CHCH ₂ , -phenyl, and the like. At this time, n is an integer of 1. Furthermore, when n is 2, it may be C1-C20 alkylene or C2-C20 alkylene such as -(CH ₂ ) ₂ -.

를 들 수 있다.As the radical where the bonding site is N, for example, when n is 1, an unsubstituted amine such as *-NH ₂ , or a substituted such as *-NH(CH ₂ ) ₂ NH ₂ or NHCONH ₂ And *-NR ¹¹ R ¹² such as amines. Also, when n is 2, *-NR ¹³ -* such as *-NH-*, *-NR ¹⁴ CONR ¹⁵ -* such as *-NHCONH-*, *-NR ¹⁶ such as *-NHCSNH-* CSNR ¹⁷ -* and the like. Furthermore, when n is 4,

Can be mentioned.

Here, R ¹¹ and R ¹² may be independently hydrogen, C1-C20 alkyl, C1-C20 aminoalkyl or CONH _2, etc., R ¹³ to R ¹⁷ may be independently hydrogen or C1-C20 alkyl, L ₁ is C1-C20alkylene.

As the radical where the bonding site is O, it may be *-O-*, where n is an integer of 2.

또는

일 수 있으며, 이때, n은 2의 정수이다.The bonding site S is a radical *-S-*, *-SS-*,

or

May be, where n is an integer of 2.

,

,

또는

를 들 수 있으며, 이때, n은 2 또는 3의 정수이다. 여기서, R₈ 및 R₉는 독립적으로, 수소, C1-C20알킬, C6-C20아릴, 또는 (C1-C20)알킬(C1-C20)알콕시일 수 있다.On the other hand, the radical where the binding site is P is

,

,

or

In this case, n is an integer of 2 or 3. Here, R ₈ and R ₉ may be independently hydrogen, C 1 -C 20 alkyl, C 6 -C 20 aryl, or (C 1 -C 20 )alkyl (C 1 -C 20 )alkoxy.

In the present invention, in the case where n is 1, in the silane compound of Formula 1, for example, Lp is a direct bond or C1-C5 alkylene, for example, C1-C3 alkylene, and p is 0 or 1 , A is hydrogen, halogen, tri(C1-C20)alkylsilyl, substituted or unsubstituted C1-C20alkyl, substituted or unsubstituted C1-C20alkenyl, *-NH ₂ , *-NH-(CH ₂ ) _l -NH ₂ , *-NH-CO-NH ₂ , *-C ₆ H ₅ or *-(CH ₂ ) _m -C ₆ H ₅ , wherein l or m can be independently an silane compound that is an integer from 1 to 10 have.

,

,

또는

이고, 여기서, R¹³ 내지 R¹⁵, R¹⁸ 및 R¹⁹는 독립적으로 수소, C1-C20알킬, C6-C20아릴, 또는 (C1-C20)알킬(C1-C20)알콕시인 실란화합물일 수 있다.Further, as the silane compound of formula 1 when n is 2, for example, Lp is C1-C5 alkylene, preferably C1-C3 alkylene, p is 0 or 1, and A is C2-C20 Alkylene, *-NR ¹³ -*, *-NR ¹⁴ -CO-NR ¹⁵ -*, *-O-*, *-S-*, *-SS-*,

,

,

or

Wherein R ¹³ to R ¹⁵ , R ¹⁸ and R ¹⁹ are independently hydrogen, C 1 -C 20 alkyl, C 6 -C 20 aryl, or (C 1 -C 20 )alkyl (C 1 -C 20 )alkoxy silane compound.

또는

인 실란화합물을 들 수 있다.In addition, when n is 3, as the silane compound of Formula 1, for example, Lp is C1-C5 alkylene, preferably C1-C3 alkylene, p is 0 or 1, and A is

or

And phosphorus silane compounds.

이며, 여기서, L₁이 C1-C10알킬렌인 실란화합물일 수 있다.Furthermore, in the case where n is 4, the silane compound of formula 1 is, for example, Lp is C1-C5 alkylene, preferably C1-C3 alkylene, p is 0 or 1, and A is

Where L ₁ is C ₁ -C 10 alkylene.

The silane compound represented by Chemical Formula 1 may be any one of silane compounds represented by Structural Formulas 1 to 16 as follows.

(1),

(2),

(3),

(4),

(5),

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

(One),

(2),

(3),

(4),

(5),

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

Oxygen contained in the silane compound as described above is bonded to the surface of the oxide film to protect the oxide film, and oxygen contained in the silane compound can hydrogen bond to the surface of the oxide film, the oxide film is etched while the nitride is etched in the etching composition This can be minimized.

In addition, the silane compound as described above is a ring-shaped silane compound, and may exist in the most stable form in the etch composition, and thus, can significantly increase the etch selectivity compared to the conventional short-chain silicone additive. . Furthermore, the structural stability of the active silicone-based additive in the etch composition is improved by including the ring-shaped compound as described above, so that the etch rate of the silicon oxide film can also be continuously maintained.

The silane compound as proposed in the present invention can effectively protect the silicon oxide film even when added in a small amount to the etching composition, thereby increasing the etching selectivity of the nitride to the oxide film. The silane compound may be added in an amount of 0.001 to 5% by weight based on the total weight of the etching composition. When the content of the silane compound is less than 0.001% by weight, it is difficult to obtain a high selectivity effect of nitride on the oxide film, and when it exceeds 5% by weight, the silane compound can be gelled, which is not preferable. For example, the silane additive is 0.001, 0.005, 0.007, 0.01, 0.03, 0.05, 0.07, 0.1, 0.15 or 0.2% by weight or more, and 5, 4.5, 4, 3.5, 3, 2.5, 2 or 1% by weight or less It can be included in a content within the range.

The silane compound used as an additive to the etching composition has low solubility. When an silane-based additive in which an appropriate solubility is not secured in the etching composition is used, or when the composition ratio is not adjusted to an appropriate level, precipitation of silicon-based particles and abnormal growth in the etching composition are caused. Such particles may remain on the silicon substrate and cause defects of devices implemented on the substrate, or may remain on equipment (eg, filters) used in an etching or cleaning process to cause equipment failure.

The etching composition of the present invention can improve the selectivity to nitride by suppressing the etching of the oxide by the silane compound as described above, while suppressing the production of silica to obtain the effect of suppressing particle formation and improving storage stability.

On the other hand, SiO ₂ H ₂ O in Equation 1 may exhibit an abnormal growth phenomenon that is usually deposited on the surface of the oxide film to increase the thickness of the oxide film. In particular, when the etching process of the nitride is accumulated in the etching composition, the concentration of SiO ₂ H ₂ O in the etching composition may be increased, and the increase in the concentration of SiO ₂ H ₂ O increases the degree of abnormal growth. can do. That is, in the initial etching composition, even if abnormal growth by SiO ₂ H ₂ O does not occur, the frequency of abnormal growth may increase as the number of cumulative processes increases. However, when the silane compound according to the present invention is included, it is possible to suppress the occurrence of such abnormal growth.

In the etching composition of the present invention, the balance is a solvent. The solvent is not particularly limited, but may be water.

The etching composition of the present invention may further include a silane compound represented by the following Chemical Formula 2.

In Chemical Formula 2, R ⁵¹ to R ⁵⁴ are each independently hydrogen, C1-C20 hydrocarbyl, C1-C20 heterohydrocarbyl, and R ⁵¹ to R ⁵⁴ are each present, or two or more are linked to each other through a hetero element It is ring-shaped. For example, hydrogen, C1-C20 alkyl or C1-C20 heteroalkyl, and the like. In this case, the hetero element is not particularly limited, but may be, for example, N, S, O, P, and the like.

The silane compound represented by Chemical Formula 2 may be included in an amount of 0.005 to 1% by weight based on the total etch composition weight.

Furthermore, an ammonium salt may also be added to the etching composition of the present invention. Ammonium salt can prevent the gelation of the etching composition, it can be added in an amount of 0.001 to 10% by weight relative to the total weight. When added to less than 0.001% by weight, the effect of improving the property of lowering gelation is negligible, and when it is added in excess of 10% by weight, ammonium salt may cause gelation.

As the ammonium salt, as a compound having ammonium ions, those commonly used in the field to which the present invention pertains can be suitably used in the present invention. Examples of the ammonium salt include, but are not limited to, ammonia water, ammonium chloride, ammonium acetic acid, ammonium phosphate, ammonium and oxydisulfate, ammonium sulfate, ammonium fluoride, etc., and any one of them can be used alone. Of course, it is also possible to use a mixture of two or more.

Furthermore, the etching composition of the present invention may further include any additives commonly used in the art to further improve etching performance. Additives include surfactants, metal ion blockers, and corrosion inhibitors.

The etching composition of the present invention is used to selectively remove the nitride film from a semiconductor device including an oxide film and a nitride film, and the nitride film may include a silicon nitride film, for example, a SiN film, a SiON film, and the like.

In addition, the oxide film is a silicon oxide film, such as SOD (Spin On Dielectric) film, HDP (High Density Plasma) film, thermal oxide (thermal oxide) film, BPSG (Borophosphate Silicate Glass) film, PSG (Phospho Silicate Glass) film, BSG Boro Silicate Glass (PSZ), Polysilazane (PSZ), Fluorinated Silicate (FSG), LPTEOS (Low Pressure Tetra Ethyl Ortho Silicate), PETEOS (Plasma Enhanced Tetra Ethyl Ortho Silicate), HTO (High Temperature Oxide), MTO (Medium Temperature Oxide) film, USG (Undopped Silicate Glass) film, SOG (Spin On Glass) film, APL (Advanced Planarization Layer) film, ALD (Atomic Layer Deposition) film, PE-Oxide film (Plasma Enhanced oxide), O3 -TEOS (O3-Tetra Ethyl Ortho Silicate) membrane and at least one membrane selected from the group consisting of combinations.

The etching process using the etching composition of the present invention may be performed by a wet etching method, such as a immersion method or a spraying method.

Examples of the etching process using the etching composition of the present invention are schematically illustrated in FIGS. 1 and 2. 1 and 2 are process sectional views showing an element separation process of a flash memory device as an example.

First, as shown in FIG. 1, after forming a tunnel oxide film 11, a polysilicon film 12, a buffer oxide film 13 and a pad nitride film 14 on the substrate 10 in turn, the polysilicon film 12 ), the buffer oxide film 13 and the pad nitride film 14 are selectively etched to form a trench. Subsequently, the SOD oxide film 15 is formed until the trench is filled, and then the COD process is performed on the SOD oxide film 15 using the pad nitride film 14 as a polishing stop film.

Next, as shown in FIG. 2, after removing the pad nitride film 14 by wet etching using a phosphoric acid solution, the buffer oxide film 13 is removed by a cleaning process. As a result, the device isolation film 15A is formed in the field region.

During the etching process, the process temperature may be in the range of 50 to 300°C, preferably in the range of 100 to 200°C, more preferably in the range of 156°C to 163°C, and an appropriate temperature is required considering other processes and other factors It can be changed according to.

According to the method for manufacturing a semiconductor device including an etching process performed using the etching composition of the present invention, selective etching of the nitride film is possible when the nitride film and the oxide film are alternately stacked or mixed. In addition, it is possible to secure the stability and reliability of the process by preventing the generation of particles that have been a problem in the conventional etching process.

Therefore, this method can be effectively applied to various processes that require selective etching of the nitride film with respect to the oxide film in the semiconductor device manufacturing process.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. The following examples are for one example of the present invention, and the present invention is not limited thereby.

Synthesis Example 1

In a 100 ml round-bottom flask, 22.5 g of 2-[bis(2-hydroxypropyl)amino]phenol, 17.0 g of chloromethyl trimethoxysilane, and 30 ml of toluene were added, followed by heating to 130° C. and stirring for 24 hours.

Thereafter, methanol was removed under reduced pressure, the mixture was further stirred for 2 hours, cooled to room temperature, and filtered to obtain a white solid.

Silane additive 1[2-(chloromethyl)-4,5-dihydro-4,12-dimethyl-2,6-(epoxyethano)- purified by white toluene re-slurry) 6.2g of 6H-1,3,6,2-benzodioxazacilcin] was synthesized.

¹ H-NMR (CDCl ₃ ) 6.93 (q, J =7.6 Hz 2H), 6.81 (d, J =7.6 Hz, 1H), 6.72 (d, J =7.6 Hz, 1H),

Synthesis Example 2

In a 100 mL round-bottom flask, 29.3 g of 2,2',2''-nitrile trisphenol, 14.8 g of vinyl trimethoxysilane, and 30 mL of toluene were added, and the mixture was heated to 130°C and stirred for 24 hours.

Thereafter, methanol was removed under reduced pressure, the mixture was further stirred for 2 hours, cooled to room temperature, and filtered to obtain a white solid.

Silane additive 2[6-ethenyl-6,12-(epoxy[1.2]benzeno)-12H-dibenzo[d,g][1,3,6,2] purified from the white solid through toluene reslurry. ] Dioxazacilosin] 4.7g was synthesized.

¹ H-NMR (CDCl ₃ ) 7.58(d, J =8.4 Hz, 1H), 7.33~7.24(m, 5H), 7.17(d, J =8.4 Hz, 1H), 7.13~7.05(m, 4H), 6.97 (d, J = 8.4 Hz, 1H), 6.53 (dd, J1 = 10.3 Hz, J2 = 16.8 Hz, 1H), 5.39 (dd, J1 = 10.3 Hz, J = 1.3 Hz, 1H), 5.23 (dd, J =16.8 Hz, J =1.3 Hz, 1H)

Synthesis Example 3

In a 100 ml round-bottom flask, 24.7 g of 1-[bis(2-hydroxyethyl)amino]-2-naphthalenol, 13.6 g of methyltrimethoxysilane, and 30 ml of toluene were added, and the temperature was raised to 130°C and stirred for 24 hours. Did.

Thereafter, methanol was removed under reduced pressure, the mixture was further stirred for 2 hours, cooled to room temperature, and filtered to obtain a white solid.

Silane additive 3[5-methyl-2,3-dihydro-1H-5,1-(epoxyethano)naphtho(2,1-d)[1,3] purified from the white solid through toluene reslurry. ,2]dioxasilosine] 2.5g was synthesized.

¹ H-NMR (CDCl ₃ ) 7.96(d, J =8.4 Hz, 1H), 7.78(d, J =8.8 Hz, 1H), 7.72(d, J =8.1 Hz, 1H), 7.28~7.18(m, 2H), 6.88(d, J =8.8 Hz, 1H), 4.39~4.26(m, 1H), 4.23~4.13(m, 1H), 4.12~4.03(m, 1H), 4.02~3.92(m, 1H) , 3.92~3.81(m, 1H), 3.75~3.60(m, 2H), 3.39(dt, J1 =16.1 Hz, J =3.4 Hz, 1H), 0.47(s, 3H)

Synthesis Example 4

20.3 g of 2-[bis(2-hydroxyethyl)amino]cyclohexanol and 22.2 g of trimethoxy[2-(trimethylsilyl)ethyl]silane and 30 ml of toluene were placed in a 100 ml round-bottom flask, and then heated to 130°C. It heated up and stirred for 24 hours.

Thereafter, methanol was removed under reduced pressure, the mixture was further stirred for 2 hours, cooled to room temperature, and filtered to obtain a white solid.

Silane additive 4 [octahydro-2-[2-(trimethylsilyl)ethyl]-2,6-(epoxyethano)-6H-1,3,6,2-purified silane additive to the white solid through toluene reslurry. Benzodioxazacilosin] 5.1 g was synthesized.

¹ H-NMR (CDCl ₃ ) 4.65~4.58(m, 1H), 4.02~3.80(m, 4H), 3.35~3.19(m, 4H), 3.05~2.98(m, 1H), 2.17~2.08(m, 1H), 2.05~1.85(m, 3H), 1.77~1.67(m, 1H), 1.57~1.45(m, 2H), 1.40~1.33(m, 1H), 1.16(t, J =6.8 Hz, 2H) , 0.78 (t, J =6.8 Hz, 2H), 0.03 (s, 9H)

Synthesis Example 5

After adding 25.7 g of 2-[bis(2-hydroxycyclohexyl)amino]ethanol, 22.2 g of trimethoxy[2-(trimethylsilyl)ethyl]silane, and 30 ml of toluene to a 100 mL round-bottom flask, the temperature was raised to 130°C. And stirred for 24 hours.

Thereafter, methanol was removed under reduced pressure, the mixture was further stirred for 2 hours, cooled to room temperature, and filtered to obtain a white solid.

Silane additive 5[6-(2-(trimethylsilyl)ethyl)dodecahydro-6,12-(epoxyethano)dibenzo[d,g][1,3] as the white solid purified through toluene reslurry. ,6]Dioxazosin] 3.2 g was synthesized.

¹ H-NMR(CDCl ₃ ) 4.52~4.44(m, 1H), 4.23(d, J =6.9 Hz, 1H), 4.07~3.94(m, 2H), 3.32(t, J =7.2 Hz, 1H), 3.25~3.10(m, 2H), 3.01(dd, J1 =10.1 Hz, J2 =3.6 Hz, 1H), 1.90~1.73(m, 4H), 1.70~1.50(m, 7H), 1.50~1.32(m, 4H), 1.30~1.20(m, 1H), 1.16(t, J =6.7 Hz, 2H), 0.76(t, J =6.7 Hz, 2H), 0.03(s, 9H)

Example 1

A substrate on which a silicon oxide film (SiOx) and a silicon nitride film (SiN) having a thickness of 5000 mm 3 were deposited on a semiconductor wafer was prepared.

As shown in Table 1, 85% phosphoric acid, 99.5% by weight, and 0.5% by weight of silane additive 1 were added to mix to 100% by weight to prepare an etch composition.

The etching composition was placed in a round flask, heated to 60 minutes to 158° C., and then etched by immersing the silicon wafer for 720 seconds and 6000 seconds to perform an etching process.

After selectively etching the surface of the silicon wafer on which the pattern is formed, the thickness of the film before and after the etching of the silicon oxide film and the nitride film is measured using an ellipsomitrie, a thin film thickness measurement equipment (NANO VIEW, SEMG-1000), from which The etching rate (SiN E/R, Å/min) of the silicon oxide film and the etching rate (SiN E/R, Å/min) and selectivity of the nitride film were calculated. Table 1 shows the results.

The selection ratio represents the ratio of the etching rate of the nitride film to the etching rate of the oxide film, and is a value calculated by dividing the difference between the initial value and the film thickness after the etching process by the etching time (minutes).

Examples 2 to 5

The etching process was performed in the same manner as in Example 1, except that the silane additives 2 to 5 were used, the etching rate of the silicon oxide film and the etching rate and selectivity of the nitride film were calculated, and the results are shown in Table 1.

Comparative Example 1

The etching process was performed in the same manner as in Example 1, except that 3-aminopropylsilanetriol was used as an additive, and the etching rate and selectivity of the silicon oxide film and the nitride film were calculated. Table 1 shows.

Composition (% by weight) Process temperature
(℃) SiN E/R
(Å/min) SiO E/R
(Å/min) Selection 85% phosphoric acid Types and contents of silane additives Comparative Example 1 99.5 3-aminopropylsilanetriol, 0.5 wt% 158 68.3 0.32 213 Example 1 99.5 Silane additive 1, 0.5wt% 158 83.6 0.15 557 Example 2 99.5 Silane additive 2, 0.5wt% 158 88.3 0.13 679 Example 3 99.5 Silane additive 3, 0.5wt% 158 94.8 0.08 1185 Example 4 99.5 Silane additive 4, 0.5wt% 158 93.2 0.09 1036 Example 5 99.5 Silane additive 5, 0.5wt% 158 91.2 0.11 829

As can be seen from Table 1, when the additives containing ring-like compounds were mixed and applied to the etching composition as in Examples 1 to 5, the etch selectivity was remarkably higher than that of Comparative Example 1, and as the etching composition of the silicon nitride film. It showed a remarkable effect. In addition, in terms of the etching rate (SiN E/R) of the silicon nitride film, it was confirmed that it is possible to provide an etching composition optimized for the etching process of the silicon nitride film by showing a remarkably superior effect compared to the etching composition of Comparative Example 1.

From these results, when the silane compound proposed in the present invention is used as an additive, it can be seen that the result of improvement of the stability of the active silicon-based structure compared to the silane compound of the single chain structure of Comparative Example 1 is used to select the etching rate and etching of the silicon nitride film. It was confirmed that an etch composition capable of improving the etch process efficiency by improving the rain and etch stability can be provided.

Claims (23)

An etching composition comprising phosphoric acid and a silane compound represented by Formula 1 below.
[Formula 1]

In Chemical Formula 1,
R ¹ to R ⁶ are independently hydrogen, hydrocarbyl or non-hydrocarbyl, and at least one pair of R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ are mutually Forming a linked substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group,
L _p is hydrocarbylene, p is 0 or 1,
A is an n-valent radical, and n is an integer from 1 to 4. The method according to claim 1, wherein R ¹ and R ² , R ³ and R ⁴ and at least one pair of R ⁵ and R ⁶ are a substituted or unsubstituted aryl group or a substituted or unsubstituted cycloalkyl group, and the rest are hydrogen. Etch composition. The etching composition of claim 1, wherein L _p is C1-C5 alkylene, and p is 1. According to claim 1, A is hydrogen, halogen, tri(C1-C20)alkylsilyl, hydrocarbylene, a radical having a bonding site of N, a radical having a bonding site of O, a radical having a bonding site of S, or a bonding site of P Phosphorus radical etching composition. The etching composition of claim 4, wherein the hydrocarbylene is C1-C20 alkyl, C6-C20 aryl or C2-C20 alkenyl. The method according to claim 4, wherein the radical having a binding site of N is *-NR ¹¹ R ¹² , *-NR ¹³ -*, *-NR ¹⁴ CONR ¹⁵ -*, *-NR ¹⁶ CSNR ¹⁷ -* or

Phosphorus etching composition.
Wherein R ¹¹ and R ¹² are independently hydrogen, C1-C20 alkyl, C1-C20 aminoalkyl or CONH ₂ , R ¹³ to R ¹⁷ are independently hydrogen or C1-C20 alkyl, L ₁ is C1-C20 alkyl It's Ren. The etching composition of claim 4, wherein the radical having the bonding site O is *-O-*. The method according to claim 4, wherein the radical having the bonding site S is *-S-*, *-SS-*,

or

Phosphorus etching composition. The radical of claim 6, wherein the binding site is P.

,

,

or

Phosphorus etching composition.
Here, R ¹⁸ and R ¹⁹ are independently hydrogen, C1-C20 alkyl, C6-C20 aryl, or (C1-C20)alkyl(C1-C20)alkoxy. According to claim 1,
n is 1,
L _p is C1 to C5 alkylene, p is 0 or 1,
A is hydrogen, halogen, tri(C1-C20)alkylsilyl, substituted or unsubstituted C1-C20alkyl, substituted or unsubstituted C1-C20alkenyl, *-NH ₂ , *-NH-(CH ₂ ) _l -NH ₂ , *-NH-CO-NH ₂ , or *-(CH ₂ ) _m -C ₆ H ₅ ,
and l and m are independently an etch composition of 0 to 10. According to claim 1,
n is 2,
L _p is C1-C5 alkylene, p is 0 or 1,
A is C1-C20 alkylene, *-NR ¹³ -*, *-NR ¹⁴ -CO-NR ¹⁵ -*, *-O-*, *-S-*, *-SS-*,

,

,

, or

ego,
Wherein R ¹³ to R ¹⁵ , R ¹⁸ and R ¹⁹ are independently hydrogen, C 1 -C 20 alkyl, C 6 -C 20 aryl, or (C 1 -C 20 )alkyl (C 1 -C 20 )alkoxy. According to claim 1,
n is 3,
L _p is C1-C5 alkylene, p is 0 or 1,
A is

or

Phosphorus etching composition. According to claim 1,
n is 4,
L _p is C1-C5 alkylene, p is 0 or 1,
A is

And
Wherein L ₁ is C1-C10 alkylene, the etching composition. The etching composition of claim 1, wherein the silane compound is selected from the following structures.

(One),

(2),

(3),

(4),

(5),

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16) The etching composition according to any one of claims 1 to 14, wherein the etching composition comprises 0.001 to 5% by weight of a silane compound represented by Chemical Formula 1. The etching composition according to any one of claims 1 to 14, comprising 70 to 90% by weight of phosphoric acid, 0.001 to 5% by weight of a silane compound represented by Chemical Formula 1, and balance water. 16. The etching composition of claim 15, further comprising a silane compound represented by Formula 2 below.
[Formula 2]

In Formula 2, R ⁵¹ to R ⁵⁴ are independently of each other hydrogen, C ₁ -C ₂₀ hydrocarbyl, C ₁ -C ₂₀ heterohydrocarbyl, and R ⁵¹ to R ⁵⁴ are each present, or two or more are It is a ring form connected to each other through a hetero element. The etching composition of claim 16, further comprising an ammonium salt. The etching method of the insulating film using the etching composition of any one of claims 1 to 14. A method of manufacturing a semiconductor device including the etching method of the insulating film of claim 19. Silane compound represented by the following formula (1).
[Formula 1]

In Chemical Formula 1,
R ¹ to R ⁶ are independently hydrogen, hydrocarbyl or non-hydrocarbyl, and at least one pair of R ¹ and R ² , R ³ and R ⁴ and R ⁵ and R ⁶ is Form a naphthalene group,
L _p is C1-C5 hydrocarbylene, p is 0 or 1,
A is hydrogen, halogen, tri(C1-C20)alkylsilyl, C1-C20alkyl, C2-C20alkenyl or C6-C20aryl,
n is 1. The method of claim 21, wherein the formula 1 is a silane compound represented by the following structure.

Silane compound represented by any one of the following structures.

(6),

(7),

(8),

(9),

(10),

(11),

(12),

(13),

(14)

(15),

(16)

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