KR20210100923A - A metal layer etchant composition and a pattern formation method using the same - Google Patents

Abstract

The present invention relates to a metal film etchant composition and a pattern forming method using the same, wherein the metal film etchant composition includes a fluorine compound that does not contain hydrogen fluoride (HF); periodic acid derivatives; an insulating film corrosion inhibitor; and water, and the insulating film corrosion inhibitor includes a compound including at least one of a sulfonate salt and a sulfate salt. The etchant composition of the present invention is capable of not only realizing high etching performance when etching a metal film but also preventing damage to an insulating film.

Description

Metal film etchant composition and pattern formation method using the same

The present invention relates to a metal film etchant composition and a pattern formation method using the same.

Titanium nitride (TiN), a titanium-based metal, is a precious metal or aluminum (Al), copper (Cu) wire used as a base layer or used as a cap layer. Moreover, in a semiconductor device, it may be used as a barrier metal and a gate metal.

Tungsten or tungsten-based metals have been mainly used together with titanium nitride to form gate electrodes, wirings, barrier layers, contact holes, and via holes of thin film transistors provided in liquid crystal displays and semiconductor devices until now. However, in recent years, as the problem of resistance to the tungsten-based film has been raised, the tungsten-based film has been replaced with a molybdenum-based film or a ruthenium-based film.

For example, in the manufacture of a semiconductor device, a liquid crystal display, etc., a titanium nitride film and a molybdenum film may be laminated|stacked on a board|substrate. An etching process for the titanium nitride and molybdenum layers may be performed according to the necessity of forming various patterns included in such semiconductor devices, liquid crystal displays, and the like. The manufacturing process of a semiconductor device, a liquid crystal display, etc. is an ultra-fine/ultra-precision process, and when an etch rate for each film quality suitable for the process is not satisfied, circuit performance is deteriorated due to pattern collapse. Accordingly, in the etching process of the metal multilayer film, it is important that each layer is etched according to a specific etch rate required in each etching process.

On the other hand, in the related art, as disclosed in Korean Patent Application Laid-Open No. 10-2016-0014714, a composition and method for selective etching of titanium nitride have been disclosed, but used to etch a molybdenum film together with a titanium nitride film. The etchant used is not well known. In addition, in the case of the composition disclosed in the above patent document, a problem of damaging an insulating film such as SiOx or SiNx may occur in the process of etching the titanium nitride film.

Republic of Korea Patent Publication No. 10-2016-0014714

The present invention is intended to improve the problems of the prior art, and it is possible to realize high etching performance when etching a metal film such as a titanium nitride film and a molybdenum film, as well as prevent damage to an insulating film such as SiOx, SiNx, etc. An object of the present invention is to provide an etchant composition that can

In addition, an object of the present invention is to provide a pattern forming method using the above-described etchant composition.

In order to achieve the above object, the present invention is a fluorine compound that does not contain hydrogen fluoride (HF); periodic acid derivatives; It provides an insulating film corrosion inhibitor, and water, wherein the insulating film corrosion inhibitor comprises a compound comprising at least one of a sulfonate salt and a sulfate salt, wherein the insulating film corrosion inhibitor provides a metal film etchant composition.

In addition, forming a titanium nitride film and a molybdenum film on the substrate; and etching the titanium nitride layer and the molybdenum layer using the above-described etching solution composition.

The etchant composition of the present invention can implement high etching performance when etching the metal film of the titanium nitride film and the molybdenum film. For example, when the metal film is etched using the etchant composition of the present invention, excellent etching rates for the titanium nitride film and the molybdenum film can be exhibited. It can provide the effect of having

In addition, the etchant composition of the present invention can provide the effect of storage stability over time while minimizing damage to the insulating film such as silicon oxide, silicon nitride, etc., which are protective films.

1 is a view for explaining that the insulating film is prevented from being damaged when the metal film is etched with the etchant composition according to an embodiment of the present invention.

The present invention relates to a fluorine compound that does not contain hydrogen fluoride (HF); periodic acid derivatives; insulating film corrosion inhibitor; and water, and the insulating film corrosion inhibitor relates to a metal film etchant composition comprising a compound including at least one of a sulfonate salt and a sulfate salt, and a pattern forming method using the same.

In the present invention, the metal film means a multi-metal film of a titanium nitride film and a molybdenum film. When the metal film of the titanium nitride film and the molybdenum film is etched with the metal film etchant composition of the present invention including the above-described components, excellent etching rates for the titanium nitride film and the molybdenum film can be exhibited, and in particular, molybdenum It is possible to provide the effect of having excellent surface roughness by uniformly removing the film to a specific thickness. In addition, the etchant composition of the present invention can provide the effect of storage stability over time while minimizing damage to the insulating film such as silicon oxide, silicon nitride, etc., which are protective films.

On the other hand, in the case of the etchant composition of the present invention, the pH range for the entire composition is preferably less than 6, more preferably less than 4, and most preferably less than 2.

In the region of pH 6 or higher, the oxidizing power of the titanium nitride film is lowered due to the reduction of the oxidation-reduction potential of the oxidizing agent, and the etching rate is significantly reduced, which may increase the processing time or have an unwanted effect on the device. On the other hand, in the scope of the present invention, the etching performance of the titanium nitride film increases due to the increase in the oxidizing power of the oxidizing agent.

In addition, since the etching amount of the metal film such as molybdenum depends only on the content of the oxidizing agent, there is no change in the etching amount depending on the pH, thereby realizing a high selectivity. However, there may be a problem in that the etching amount of SiOx and SiNx, which are protective film materials, also increases.

Hereinafter, the configuration of the etchant composition of the present invention will be described in detail.

<Etchant composition>

The etchant composition of the present invention includes a fluorine compound not containing hydrogen fluoride (HF) as a component for etching a metal film, a periodic acid derivative, and an insulating film corrosion inhibitor, and may include water as a solvent. If necessary, it may further include a pH adjusting agent.

fluorine compounds

The etchant composition of the present invention includes a fluorine compound as a component for etching the form _{of TiO X oxidized by a periodic acid derivative to TiF 4 form when the metal film is etched.}

As a fluorine compound included in the etchant composition of the present invention, for example, zirco _{hydrofluoric acid (H 2 ZrF 6} ), titanic _{acid fluoride (H 2} TiF ₆ ), hexafluorophosphoric acid (HPF ₆ ), ammonium fluoride, tetrafluoroboric acid, tetrafluoroborate (TBA-BF ₄ ), tetraalkylammonium fluoride (NR ₁ R ₂ R ₃ R ₄ F), hexafluorosilicic acid (H ₂ SiF ₆ ), and combinations thereof It may include one or more species selected from the group consisting of. In this case, in NR ₁ R ₂ R ₃ R ₄ F of _{the tetraalkylammonium fluoride, R 1} , R ₂ , R ₃ and R ₄ may be the same as or different from each other, and a group consisting of a straight-chain and branched C1-C6 alkyl group. is selected from

On the other hand, in the case of hydrogen fluoride (HF), which is known as a representative fluorine compound, it may increase the surface roughness of molybdenum in the metal film, thereby causing device defects. Therefore, it is preferable that the fluorine compound of the present invention does not contain hydrogen fluoride (HF).

Preferably, in terms of controlling the etching performance of silicon oxide (SiOx) silicon nitride (SiNx), which is a film material to be protected, to less than 2 Å/min as the fluorine compound of the present invention, hexafluorosilicic acid (H ₂ SiF _{6 )} ), borate-based fluorine compounds can be selected and used. For example, the borate-based fluorine compound may include tetrafluoroboric acid, tetrafluoroborate (TBA-BF ₄ ), and the like.

In the etchant composition of the present invention, the content of the fluorine compound may be included in an amount of 0.01 to 5% by weight based on the total weight. Preferably, it may be included in an amount of 0.05 to 1% by weight. When the fluorine compound is included in the etchant composition of the present invention in less than the content range, the etching rate of the titanium nitride film may be slowed. This is not easy, and the etching rate of the silicon nitride (SiNx), which is a protection target, is increased, so that damage to the silicon nitride (SiNx) may occur.

Periodic acid derivatives

The periodic acid derivative contained in the etchant composition of the present invention serves as a main oxidizing agent to oxidize and etch a titanium nitride (TiN) film and a molybdenum (Mo) film.

In the present invention, the periodic acid derivative may include periodic acid and a compound that can be generated from periodic acid through introduction of a specific functional group to the periodic acid, oxidation, reduction, substitution of atoms, and the like.

Periodic acid derivatives contained in the composition of the present invention include, for example, periodic acid, ammonium periodate, potassium periodate, sodium periodate, and the like. The periodic acid derivative compounds exemplified above may be included alone or in two or more types in the etchant composition of the present invention.

Meanwhile, in the etchant composition of the present invention, it is also possible to use an oxidizing agent such as nitric acid, sulfuric acid, ammonium iodate, or hydrogen peroxide as an oxidizing agent. However, nitric acid and/or sulfuric acid has a risk due to heat generation during manufacture, and oxidizing agents such as ammonium iodate may have changes in components and contents depending on the storage period, thereby reducing product reliability. In addition, in the case of hydrogen peroxide, it is difficult to control the etching rate because the silicon nitride, which is a protective film, is damaged or the molybdenum is etched quickly, and a problem of roughening the surface may occur.

Therefore, in the etchant composition of the present invention, it is most preferable to use the above-described periodic acid derivative as an oxidizing agent.

In the present invention, the periodic acid derivative (oxidizing agent) can etch titanium nitride and molybdenum nitride by the above-described fluorine compound and the following reaction formula.

Titanium nitride etching scheme:

1 ^st step: TiN + oxidant → TiO _x + NO _x + others

_{^{2 nd step: TiO x + 4HF}} → TiF 4 + 2H 2 O

Molybdenum etching scheme:

Mo + 2H ₂ O ₂ ↔ H ₂ MoO ₄ (or MoO ₃ H ₂ O) + H ₂ ↑

The periodic acid derivative contained in the etchant composition according to the present invention may be included in an amount of 0.0001 to 0.5% by weight or less, preferably 0.0005 to 0.1% by weight or less, based on the total weight of the etchant composition.

When the periodic acid derivative is included below the content range, the etching rate of the titanium nitride layer may be significantly slowed. When included in excess of the above content range, the etching rate of the titanium nitride film is too high, so it is not easy to control the etching amount in the process, so the process applicability may decrease, and the etching rate of silicon nitride etched by the following reaction formula may increase. have.

Silicon Nitride Etching Scheme:

_{^{1 st step: SiNH 2 + H}} + ↔ SiNH 3 +

_{^{2 nd step: SiNH 3 + +}} F - → SiF + NH 3

Insulation film corrosion inhibitor

The etchant composition of the present invention includes an insulating film corrosion inhibitor as a component for preventing corrosion of an insulating film such as SiOx or SiNx, that is, damage to the insulating film when the metal film is etched.

The etchant composition according to the present invention uses a compound containing a _{sulfonate salt (Sulfonate; -SO 3} ^- ) and/or a sulfate (-SO ₄ ^{-) salt as an insulating film corrosion inhibitor.} Accordingly, it is possible to effectively prevent the lower insulating film from being damaged when the metal film is etched with the etchant composition of the present invention.

In one embodiment of the present invention, it is preferable not to use a compound containing a carboxylate salt, a phosphate salt or a benzoate salt that may damage the insulating film as the insulating film corrosion inhibitor.

The insulating film corrosion inhibitor of the present invention may be an anionic surfactant containing a sulfonate salt and/or a sulfate salt.

In addition, the compound containing the sulfonate salt and/or sulfate salt contained in the insulating film corrosion inhibitor of the present invention includes those present in the form of a hydrate.

The cation of the insulating film corrosion inhibitor containing the sulfonate salt and/or sulfate salt includes sodium ion (Na ⁺ ), potassium ion (K ⁺ ), ammonium ion (NH ₄ ⁺ ), etc., but preferably ammonium ion in the semiconductor field. (NH ₄ ⁺ ) is used.

1 is a view for explaining that the insulating film is prevented from being damaged when the metal film is etched with the etchant composition according to an embodiment of the present invention.

Referring to FIG. 1 , the insulating film corrosion inhibitor of the present invention containing a sulfonate salt and/or a sulfate salt prevents corrosion of the insulating film by binding the sulfonate salt and/or sulfate salt to the surface of the insulating film having a '+' charge. can do.

In one embodiment, the insulating film corrosion inhibitor included in the etchant composition of the present invention may include at least one selected from a compound represented by the following formula (1) and a compound represented by the following formula (2).

[Formula 1]

In Formula 1, R1 is hydrogen, a linear or branched chain alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or -(CH ₂ ) _n CH ₃ and

A is -SO ₃ Na, -SO ₃ K, -SO ₃ NH ₄ , -SO ₄ Na, -SO ₄ K or -SO ₄ NH ₄ .

In the insulating film corrosion inhibitor of the present invention, the compound of Formula 1 includes those present in the form of a polymer, and in this case, may be 200,000 g/mol or less, and preferably 100,000 g/mol or less. If the molecular weight exceeds 200,000 g/mol, it may cause filter clogging and adsorption on equipment and substrates in the process.

For example, when the compound of Formula 1 exists in the form of a polymer, it may be represented by Formula 1-1 below.

[Formula 1-1]

In Formula 1-1, n may be 2 to 1000, A is -SO ₃ Na, -SO ₃ K, -SO ₃ NH ₄ , -SO ₄ Na, -SO ₄ K or -SO ₄ NH ₄ may be.

[Formula 2]

In Formula 2, R2 is hydrogen, a linear or branched chain alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a monovalent substituent containing at least one ester group having 3 to 20 carbon atoms is,

A is -SO ₃ Na, -SO ₃ K, -SO ₃ NH ₄ , -SO ₄ Na, -SO ₄ K or -SO ₄ NH ₄ .

In the present invention, as the insulating film corrosion inhibitor of the compound represented by Formula 1 or Formula 2, for example, dodecyl ammonium salt, dihexyl sulfosuccinate sodium salt, 4-styrene sulfonic acid sodium salt Hytrate, polystyrene-4-sulfonic acid ammonium salt (molecular weight 200,000 g/mol or less), ammonium para-toluene sulfonate, sodium para-toluene sulfonate, ammonium benzo sulfate, ammonium 4-vinylbenzene sulfonate, etc. It is not limited.

The insulating film corrosion inhibitor may be included in an amount of 0.001 to 1% by weight, preferably 0.005 to 0.5% by weight based on the total weight of the etchant composition. When the amount of the insulating film corrosion inhibitor is less than the content range, the effect of corrosion prevention is insignificant, and when the content exceeds the content range, the etching rate of the titanium nitride film may be affected.

pH adjuster

The etchant composition of the present invention may further include a pH adjuster, if necessary.

The pH adjusting agent does not affect the etching of the metal film and the insulating film, and may serve to adjust only the pH.

The pH adjusting agent may include, for example, ammonium hydroxide, ammonium acetate, methane sulfonic acid, and the like, but is not limited thereto.

The content of the pH adjuster included in the etchant composition of the present invention may be included in an amount of 0.01 to 25% by weight, preferably 0.5 to 20% by weight, based on the total weight of the composition.

When the pH adjusting agent is included within the above content range, the pH of the etchant composition can be easily adjusted.

water

The water included in the etchant composition of the present invention may be deionized water for a semiconductor process, and preferably 18 MΩ/cm or more of the deionized water may be used.

In the present invention, water may be included as a residual amount, and the residual amount means a residual amount such that the weight of the total composition further including the essential components and other components of the present invention is 100% by weight.

For example, when the etchant composition of the present invention includes the fluorine compound, the periodic acid derivative, and the insulating layer corrosion inhibitor, water may be included in an amount of 94 to 99% by weight based on the total weight of the composition.

< Pattern formation method >

The present invention provides a pattern forming method using the above-described etchant composition. The pattern forming method of the present invention may form a pattern according to a known pattern forming method, except that the etchant composition according to the present invention is used.

For example, the pattern forming method may include forming a titanium nitride film and a molybdenum film on a substrate. In addition, the titanium nitride layer and the molybdenum metal layer may be etched to form a pattern. In this case, the etching process may be performed using the above-described etching solution composition.

In an embodiment, a titanium nitride film and a molybdenum film may be sequentially formed on the substrate.

The substrate may include, for example, a semiconductor substrate such as a silicon substrate, a germanium substrate, or a silicon-germanium substrate. A silicon-on-insulator (SOI) substrate or a germanium-on-insulator (GOI) substrate may be used as the substrate. The substrate may include a group III-V compound such as InP, GaP, GaAs, GaSb, or the like.

According to the present invention, a semiconductor electrode such as a gate electrode, a source/drain electrode, and a pixel electrode may be formed by etching the metal layer of the titanium nitride layer and the molybdenum layer using the above-described etching solution composition.

In addition, in the present invention, a pattern that can be formed using the above-described etchant composition may be a conductive pattern, for example, may be utilized as a pad, electrode, or wiring of an image display device.

In more detail, the titanium nitride layer may be etched in a predetermined pattern to become a barrier layer, and the molybdenum metal layer may be etched in a predetermined pattern to become a gate electrode. The titanium nitride film and the molybdenum film may be an etch target film as a whole, or may be partially etched films.

The formation method of the titanium nitride film and the molybdenum film is not particularly limited, and for example, a chemical vapor deposition (CVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, and sputtering. ) process, a physical vapor deposition (PVD) process, an atomic layer deposition (ALD) process, and the like.

In an embodiment, the pattern forming method may further include forming an insulating film between the substrate and the titanium nitride and molybdenum films. The insulating layer is a layer to be protected, and may include a silicon oxide layer (SiOx), a silicon nitride layer (SiZx), or the like.

According to the present invention, the silicon oxide film and the silicon nitride film are not substantially etched or damaged through the above-described etching solution composition, and excellent etching properties can be secured only for the titanium nitride film and the molybdenum film. In particular, the molybdenum film can be uniformly etched to a specific thickness through the etchant composition of the present invention, so that it can have excellent surface roughness, thereby improving the accuracy of etching, and can be suitably used for electrode formation.

The pattern forming method of the present invention can be used for manufacturing a semiconductor device precisely processed by using the etchant composition described above, for example, it can be very usefully applied to a semiconductor device, a liquid crystal display, a MEMS device, a printed wiring board, etc. .

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are provided to illustrate the present invention in more detail, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention. In addition, "%" and "part" indicating the content hereinafter are based on weight unless otherwise specified.

Examples and Comparative Examples: Preparation of etchant composition

The etchant compositions of Examples 1 to 25 and Comparative Examples 1 to 21 were prepared with the composition and content (wt%) shown in Table 1 below.

Furtherance fluorine compounds oxidizer Insulation film corrosion inhibitor pH adjuster water Example 1 C-2 0.1wt% O-2 0.001 wt% SO-4 0.1wt% - remaining amount Example 2 C-2 0.1wt% O-2 0.001 wt% SO-6 0.0001wt% - remaining amount Example 3 C-2 0.1wt% O-2 0.001 wt% SO-6 0.001 wt% - remaining amount Example 4 C-2 0.1wt% O-2 0.001 wt% SO-6 0.05wt% - remaining amount Example 5 C-2 0.1wt% O-2 0.001 wt% SO-6 0.1wt% - remaining amount Example 6 C-2 0.1wt% O-2 0.001 wt% SO-6 1wt% - remaining amount Example 7 C-2 0.1wt% O-2 0.001 wt% SO-6 3wt% - remaining amount Example 8 C-2 0.1wt% O-2 0.001 wt% SO-8 0.005 wt% - remaining amount Example 9 C-2 0.1wt% O-2 0.001 wt% SO-8 0.1wt% - remaining amount Example 10 C-2 0.1wt% O-2 0.001 wt% SA-11 0.1wt% - remaining amount Example 11 C-2 0.1wt% O-2 0.001 wt% SO-9 0.1wt% - remaining amount Example 12 C-2 0.1wt% O-2 0.001 wt% SA-12 0.1wt% - remaining amount Example 13 C-2 0.1wt% O-2 0.001 wt% SA-10 0.1wt% - remaining amount Example 14 C-2 0.1wt% O-2 0.001 wt% SO-14 0.01wt% - remaining amount Example 15 C-2 0.1wt% O-2 0.001 wt% SO-15 0.01wt% - remaining amount Example 16 C-2 0.1wt% O-2 0.001 wt% SO-16 0.01wt% - remaining amount Example 17 C-2 0.1wt% O-2 0.0001wt% SO-16 0.01wt% - remaining amount Example 18 C-2 0.1wt% O-2 0.5wt% SO-16 0.01wt% - remaining amount Example 19 C-2 0.1wt% O-2 1wt% SO-16 0.01wt% - remaining amount Example 20 C-2 0.001 wt% O-2 0.001 wt% SO-16 0.01wt% - remaining amount Example 21 C-2 7wt% O-2 0.001 wt% SO-16 0.01wt% - remaining amount Example 22 C-2 0.1wt% O-2 0.001 wt% SO-6 0.1wt% P-1 10% remaining amount Example 23 C-2 0.1wt% O-2 0.001 wt% SO-3 0.1wt% - remaining amount Example 24 C-3 0.1wt% O-2 0.001 wt% SO-6 0.05wt% - remaining amount Example 25 C-2 0.1wt% O-2 0.001 wt% SA-1 0.01wt% - remaining amount Comparative Example 1 C-2 0.1wt% O-3 0.001 wt% SO-6 0.1wt% - remaining amount Comparative Example 2 C-1 0.1wt% O-2 0.001 wt% SO-6 0.1wt% - remaining amount Comparative Example 3 C-1 0.05wt% O-1 0.001 wt% - - remaining amount Comparative Example 4 C-1 1wt% O-1 0.001 wt% - - remaining amount Comparative Example 5 C-2 0.05wt% O-1 0.001 wt% - - remaining amount Comparative Example 6 C-2 1wt% O-1 0.001 wt% - - remaining amount Comparative Example 7 C-1 0.05wt% O-2 0.001 wt% - - remaining amount Comparative Example 8 C-1 1wt% O-2 0.001 wt% - - remaining amount Comparative Example 9 C-2 0.05wt% O-2 0.001 wt% - - remaining amount Comparative Example 10 C-2 1wt% O-2 0.001 wt% - - remaining amount Comparative Example 11 C-1 0.05wt% O-2 0.1wt% - - remaining amount Comparative Example 12 C-1 1wt% O-2 0.1wt% - - remaining amount Comparative Example 13 C-2 0.05wt% O-2 0.1wt% - - remaining amount Comparative Example 14 C-2 1wt% O-2 0.1wt% - - remaining amount Comparative Example 15 C-2 1wt% - SO-6 0.05wt%- - remaining amount Comparative Example 16 - O-2 0.1wt% SO-6 0.05wt%- - remaining amount Comparative Example 17 C-2 0.1wt% - SO-16 0.01wt% - remaining amount Comparative Example 18 C-2 0.1wt% O-2 0.001 wt% SP-13 0.1wt% - remaining amount Comparative Example 19 C-2 0.1wt% O-2 0.001 wt% SC-7 0.1wt% - remaining amount Comparative Example 20 C-2 0.1wt% O-2 0.001 wt% SC-2 0.1wt% - remaining amount Comparative Example 21 C-2 0.1wt% O-2 0.001 wt% SC-5 0.1wt% - remaining amount

main)

Fluorine compounds:

C-1: Hydrogen fluoride (HF)

C-2: Fluoroboric acid (FBA)

C-3: Fluosililic acid

Oxidizer:

O-1: Hydrogen peroxide (H ₂ O ₂ )

O-2: Periodic acid (PIA)

O-3: Ammonium iodate

Insulation film corrosion inhibitor:

SA-1: Dodecyl sulfate ammonium salt

SC-2: Ammonium benzoate

SO-3: Anthraquinone-2-sulfonic acid sodium salt

SO-4: Dihexyl sulfosuccinate sodium salt

SC-5: Ethylenediaminetetraacetic acid disodium salt

SO-6: 4-styrenesulfonic acid sodium salt hydrate

SC-7: L-Glutamic acid monosodium salt hydrate

SO-8: Poly styrene-4-sulfonic acid ammonium salt (Mw: 200,000)

SO-9: Ammonium p-toluene sulfonate

SA-10: Sodium p-toluene sulfonate

SA-11: Ammonium benzenesulfate

SA-12: Ammonium 4-vinylbenzenesulfonate

SP-13: Polyoxyethylene aryl ether phosphate

SO-14: Poly styrene-4-sulfonic acid ammonium salt (Mw: 2,500)

SO-15: Poly styrene-4-sulfonic acid ammonium salt (Mw: 10,000)

SO-16: Poly styrene-4-sulfonic acid ammonium salt (Mw: 20,000)

pH adjusters:

P-1: Ammonium hydroxide

Experimental example

(1) Evaluation of etching characteristics for titanium nitride film and molybdenum film: etching rate evaluation

A specimen was prepared by cutting a silicon wafer on which titanium nitride (TiN) and molybdenum film (Mo) were respectively deposited to a ^{size of 2 X 2 cm 2 .} The specimen was immersed in the etchant composition of Examples and Comparative Examples in a 50°C thermostat for 1 minute. Then, the specimen was taken out, washed with water and IPA (Isopropyl Alcohol), and then dried using _{N 2 gas.} For the titanium nitride film, an ellipsometer was used, and for the molybdenum film, the thickness of the film was measured after etching using XRF. The evaluation criteria are as follows. The evaluation results are shown in Table 2 below.

<Evaluation criteria>

Titanium nitride film (TiN)

◎: Etching rate 30 Å/min or more

○: Etching rate 20 Å/min or more and less than 30 Å/min

△: Etching rate 10 Å/min or more and less than 20 Å/min

×: etching rate less than 10 Å/min

Molybdenum (Mo) film

◎: Etching rate less than 10 Å/min

○: Etching rate 10 Å/min or more and less than 20 Å/min

△: Etching rate 20 Å/min or more and less than 30 Å/min

×: Etching rate 30 Å/min or more

(2) Molybdenum surface roughness characteristics evaluation

A specimen was prepared by cutting a silicon wafer on which a molybdenum film (Mo) was deposited to a ^{size of 2 X 2 cm 2 .} The specimen was immersed in the etchant composition of Examples and Comparative Examples in a thermostat set at an evaluation temperature (50° C.) for an appropriate evaluation time. Then, the specimen was taken out, washed with water and IPA (Isopropyl Alcohol), and then dried using _{N 2 gas.} A numerical value (RMS: Root Mean Square) derived by measuring the surface roughness by AFM (Atomic Force Microscopy) is compared.

<Evaluation criteria>

Molybdenum Surface Roughness (RMS: Root Mean Square)

◎: less than 0.5 nm

○: 0.5 or more and less than 1.0 nm

△: 1.0 or more and less than 5.0 nm

X: 5 nm or more

(3) SiNx etching evaluation

A specimen was prepared by cutting a silicon wafer on which silicon nitride (SiNx) was deposited into a ^{size of 2 X 2 cm 2 .} The specimens were immersed in the etchant compositions of Examples and Comparative Examples in a 50°C thermostat for 1 minute. Then, the specimen was taken out, washed with water and IPA (Isopropyl Alcohol), and then dried using _{N 2 gas.} After measuring the thickness of the film after etching using an ellipsometer, the etch rate was calculated as a change value compared to the initial film thickness. The evaluation criteria are as follows, and the results are shown in Table 2 below.

<Evaluation criteria>

Silicon Nitride (SiN) Etching Rate

◎: Etching rate less than 1 Å/min

○: Etching rate 1 or more and less than 2 Å/min

△: Etching rate 2 or more and less than 3 Å/min

X: Etching rate 4 Å/min or more

(4) evaluation of the pH properties of the composition

The etchant compositions of Examples and Comparative Examples were prepared at room temperature, stirred for 10 minutes, immersed in a sensor of a pH measuring device, and the pH value when stabilized for 1 to 3 minutes was read and recorded.

< Evaluation Criteria>

pH of the composition

◎: less than 2.0

○: 2.0 or more and less than 4.0

△: 4.0 or more and less than 6.0

X: 6.0 or higher

(5) Evaluation of storage stability of the composition

In order to commercialize the composition, there should be no change in the composition for at least 3 months. Storage stability evaluation evaluates the rate of change in the component content of the composition immediately after manufacturing and after 3 months (storage temperature is 23°C). The evaluation criteria are as follows, and the results are shown in Table 2 below.

<Stability evaluation criteria for storage (based on 3 months elapsed)>

◎: 0% change in component content of the composition

○: Less than 2% change in component content of the composition

△: change rate of component content of composition 2 or more and less than 5%

X: 5% or more of change in component content of the composition

etch rate surface roughness pH keep
stability titanium nitride molybdenum silicon nitride molybdenum 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 ○ ◎ ○ ◎ ◎ ◎ Example 14 ◎ ◎ ◎ ◎ ◎ ◎ Example 15 ◎ ◎ ◎ ◎ ◎ ◎ Example 16 ◎ ◎ ◎ ◎ ◎ ◎ Example 17 ◎ ◎ ◎ ◎ ◎ ◎ Example 18 ◎ ○ ◎ ◎ ◎ ◎ Example 19 ◎ △ △ ◎ ◎ ◎ Example 20 △ ◎ ◎ ◎ △ ◎ Example 21 ◎ ◎ △ ◎ ◎ ◎ Example 22 ○ ◎ ◎ ◎ ◎ ◎ Example 23 ○ ◎ ○ ◎ ◎ ◎ Example 24 ◎ ◎ ◎ ◎ ◎ ◎ Example 25 ◎ ◎ △ ◎ ◎ ◎ Comparative Example 1 ◎ ◎ ○ ◎ ◎ X Comparative Example 2 ◎ ◎ ○ X ◎ ◎ Comparative Example 3 ○ ◎ △ X ◎ ◎ Comparative Example 4 ◎ ◎ X X ◎ ◎ Comparative Example 5 ○ ◎ △ X ◎ ◎ Comparative Example 6 ◎ ◎ X X ◎ ◎ Comparative Example 7 ○ ◎ X △ ◎ ◎ Comparative Example 8 ◎ ◎ X X ◎ ◎ Comparative Example 9 ○ ◎ X ◎ ◎ ◎ Comparative Example 10 ◎ ◎ X ◎ ◎ ◎ Comparative Example 11 ○ ◎ X △ ◎ ◎ Comparative Example 12 ◎ ◎ X X ◎ ◎ Comparative Example 13 ○ ◎ X ○ ◎ ◎ Comparative Example 14 ◎ ◎ X ◎ ◎ ◎ Comparative Example 15 △ ◎ X ◎ ◎ ◎ Comparative Example 16 X ◎ △ ◎ ○ ◎ Comparative Example 17 X ◎ ◎ ◎ ◎ ◎ Comparative Example 18 X ◎ ◎ ○ ◎ ◎ Comparative Example 19 △ ◎ X ○ ◎ ◎ Comparative Example 20 △ ◎ X ○ ◎ ◎ Comparative Example 21 △ ◎ X ○ ◎ ◎

Referring to Table 2, when the etching solution composition according to Examples 1 to 25 of the present application is used, a good level or higher etching rate may be exhibited when etching the molybdenum film and the titanium nitride film, and in particular, the molybdenum film It can be uniformly removed to have excellent surface roughness. In addition, it was confirmed that the etchant composition according to an embodiment of the present invention can not only prevent damage to the cut film, such as a silicon nitride film, but also exhibit excellent storage stability.

In comparison, when the etching solution composition according to Comparative Examples 1 to 21 is used, the etching of the molybdenum film and/or the titanium nitride film is not sufficiently performed, or the surface of the molybdenum film is rough, and In the case of damage to the insulating film, the effect was significantly reduced compared to the etchant composition according to the embodiment.

Claims (9)

fluorine compounds that do not contain hydrogen fluoride (HF);
periodic acid derivatives;
insulating film corrosion inhibitor; and
contains water,
The insulating film corrosion inhibitor is a metal film etchant composition comprising a compound comprising at least one of a sulfonate salt and a sulfate salt. The method according to claim 1, wherein the fluorine compound that does not contain hydrogen fluoride (HF) is zircohydrofluoric _{acid (H 2 ZrF 6} ), titanic _{acid fluoride (H 2} TiF ₆ ), hexafluorophosphoric acid (HPF ₆ ), ammonium fluoride , tetrafluoroboric acid, tetrafluoroborate (TBA-BF ₄ ), tetraalkylammonium fluoride, and hexafluorosilicic acid (H ₂ SiF ₆ ) At least one selected from the group consisting of, the metal film etching solution composition. The metal film etchant composition of claim 1, wherein the periodic acid derivative is at least one selected from periodic acid, ammonium periodate, potassium periodate, and sodium periodate. The method according to claim 1, The insulating film corrosion inhibitor comprising at least one selected from a compound represented by the following formula (1) and a compound represented by the following formula (2), metal film etchant composition.
[Formula 1]

(In Formula 1, R1 is hydrogen, a linear or branched chain alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms,
A is -SO ₃ Na, -SO ₃ K, -SO ₃ NH ₄ , -SO ₄ Na, -SO ₄ K or -SO ₄ NH ₄ )
[Formula 2]

(In Formula 2, R2 is hydrogen, a linear or branched chain alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a monovalent ester group containing at least one ester group having 3 to 20 carbon atoms. is a substituent,
A is -SO ₃ Na, -SO ₃ K, -SO ₃ NH ₄ , -SO ₄ Na, -SO ₄ K or -SO ₄ NH ₄ ) The method according to claim 4, The insulating film corrosion inhibitor is a molecular weight of 200,000 g / mol or less of a polymer compound, the metal film etchant composition. The method according to claim 4, wherein the insulating film corrosion inhibitor is dodecyl sulfate ammonium salt, dihexyl sulfosuccinate sodium salt, 4-styrene sulfonic acid sodium salt hydrate, polystyrene-4-sulfonic acid ammonium salt, ammonium paratoluene sulfonate, A metal film etchant composition comprising at least one selected from the group consisting of sodium paratoluenesulfonate, ammonium benzosulfate, and ammonium 4-vinylbenzenesulfonate. The method according to claim 1, For protecting silicon oxide (SiOx) and silicon nitride (SiNx), the etchant composition. The method according to claim 1,
with respect to the total weight of the composition,
0.01 to 5 wt% of a fluorine compound not containing hydrogen fluoride (HF);
0.0001 to 0.5 wt% of a periodic acid derivative;
0.001 to 1% by weight of an insulating film corrosion inhibitor; and
An etchant composition comprising the remaining amount of water. forming a metal nitride film and a molybdenum-based metal film on a substrate; and
A method of forming a pattern comprising a; etching the metal nitride layer and the molybdenum-based metal layer using the etchant composition of any one of claims 1 to 8.

Images