KR20230024062A - Post-cmp cleaning solution composition - Google Patents

Abstract

The present invention provides a post-CMP cleaning solution composition capable of selectively etching the film surface of a wafer to facilitate removal of residual particles and organic matter and reducing surface defects after a CMP process of a semiconductor wafer using a polishing slurry, and a cleaning method using the same. The post-CMP cleaning solution composition includes organic acid; a phosphoric acid compound; and a nitrate compounds.

Description

Cleaning liquid composition after CMP {POST-CMP CLEANING SOLUTION COMPOSITION}

The present invention relates to a post-CMP cleaning liquid composition.

As miniaturization of semiconductor devices progresses, high precision is required for flatness of each layer of a substrate. In addition, in order to increase production efficiency, a technique for simultaneously flattening surfaces having different hardness or properties is required.

As a technique for securing flatness of a substrate for a semiconductor device, chemical mechanical polishing (CMP) is generally used. Chemical mechanical polishing is a technology of polishing and flattening the surface of a substrate using an abrasive pad while supplying an abrasive containing abrasive particles. The abrasive includes silica slurry using silica particles as abrasive particles, and ceria slurry using ceria particles as abrasive particles. is widely used.

After the polishing process is performed using an abrasive such as silica slurry or ceria slurry, a cleaning process is required to remove polishing debris, particles, organic residues, and by-products remaining on the surface of the substrate.

After performing the CMP process using the abrasive particle slurry, hydrofluoric acid cleaning or cleaning using dilute hydrogen fluoride (dHF) is usually performed to remove ceria, which is abrasive particles remaining on the substrate surface, followed by SC-1 ( Standard Clean-1 (APM) cleaning solution is used for cleaning.

However, the SC-1 cleaning has problems in that film loss occurs due to etching of the wafer film, and a large number of surface defects exist due to the abrasive particle slurry remaining after cleaning.

Therefore, it is necessary to develop a cleaning liquid composition capable of improving surface defects while reducing film loss after a CMP process using an abrasive particle slurry.

The above background art is possessed or acquired by the inventor in the process of deriving the disclosure of the present application, and cannot necessarily be said to be known art disclosed to the general public prior to the present application.

The present invention, in order to solve the above-mentioned problems, after the CMP process of a semiconductor wafer using a polishing slurry, selectively etch the film surface of the wafer to facilitate the removal of residual particles and organic matter, and to improve surface defects. A cleaning liquid composition after CMP and a cleaning method using the same are provided.

In addition, the present invention provides a post-CMP cleaning solution composition capable of smoothly performing subsequent processes by removing surface defects on a silicon oxide film or silicon nitride film and dissolving abrasive particles of the polishing slurry.

However, the problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one embodiment of the present invention, an organic acid; phosphoric acid compounds; And a nitrate compound; it relates to a post-CMP cleaning liquid composition comprising a.

According to one embodiment of the present invention, the organic acid is an organic acid containing at least one carboxyl group, and the organic acid is citric acid, lactic acid, gluconic acid, or maleic acid. acid, malic acid, malonic acid, adipic acid, succinic acid, tartaric acid, glutaric acid, glycolic acid , aspartic acid, itaconic acid, glutamic acid, tricarballylic acid, pimelic acid, suberic acid, sebacic acid , stearic acid, pyruvic acid, acetoacetic acid, glyoxylic acid, azelaic acid, fumaric acid, glutaconic acid, Traumatic acid, muconic acid, aconitic acid, carballylic acid, tribasic acid, mellitic acid, isocitric acid , citric acid, lactic acid, gluconic acid, maleic acid, ascorbic acid, iminoacetic acid, oxalic acid, pyrogalic acid (pyrogallic acid), formic acid, acetic acid, propionic acid, butyric acid, valeric acid ic acid, hexanoic acid, heptanoic acid, caprylic acid, nonanoic acid, decanoic acid, undecylenic acid, laurylic acid It may contain at least one selected from the group consisting of lauric acid, tridecylic acid, myristic acid, pentadecanoic acid, and palmitic acid. there is.

According to one embodiment of the present invention, the content of the organic acid may be 1% to 5% by weight of the cleaning liquid composition.

According to one embodiment of the present invention, the phosphoric acid-based compound is phosphoric acid, pyrophosphoric acid, polyphosphoric acid, metaphosphoric acid, hypophosphoric acid, triphosphoric acid Triphosphoric acid, Phosphorus trioxide Phosphorus pentoxide, Peroxymonophosphoric acid, Peroxydiphosphoric acid, Phosphorous acid, Hypophosphorous acid, Phosphate ), phosphonic acid (phosphonic acid, RPO ₃ H ₂ ), and may include at least one selected from the group consisting of salts thereof.

According to one embodiment of the present invention, the phosphoric acid-based compound may be 10% to 20% by weight of the cleaning liquid composition.

According to an embodiment of the present invention, the nitrate compound may include at least one selected from the group consisting of nitric acid, ammonium nitrate, and sodium nitrate.

According to one embodiment of the present invention, the weight ratio of the organic acid: the nitrate compound: the phosphoric acid-based compound may be 1: 0.1 to 2: 2 to 7.

According to one embodiment of the present invention, the cleaning liquid composition, a sulfur compound; Further, the weight ratio of the organic acid: the sulfur compound may be 1: 3 to 1: 6, and the weight ratio of the sulfur compound: the phosphoric acid-based compound may be 1: 0.5 to 1: 2.

According to an embodiment of the present invention, the sulfur compound is sulfuric acid, thiosulfuric acid (H ₂ S ₂ O ₃ ), sulfide, bisulfide (RSS-R'), Hydrogen sulfide (H ₂ S), sulfur trioxide (SO ₃ ), sulfenic acid (RSOH), sulfinic acid (RSO (OH)), thiosulfonic acid (RSO₂SH), thio A thiocarboxylic acid (RC(S)OH), a sulfate, a sulfonate (R-SO₃, R-SO₃-R'), an organic sulfonic acid, a salt of one or more of these, and one of these It may contain at least one or more selected from the group consisting of the above anhydrides.

According to an embodiment of the present invention, the organic sulfonic acid may include at least one selected from the group consisting of alkanesulfonic acid, alkanolsulfonic acid, sulfosuccinic acid, and aromatic sulfonic acid.

According to one embodiment of the present invention, the sulfur compound may be 10% to 20% by weight of the cleaning liquid composition.

According to one embodiment of the present invention, a fluoride compound; It further includes, wherein the fluoride compound is hydrofluoric acid, ammonium fluoride, ammonium bifluoride, ammonium silicofluoride, sodium fluoride , barium fluoride, calcium fluoride, magnesium fluoride, potassium fluoride, aluminum fluoride, aminobenzotrifluoride, Boron trifluoride, cobalt(II) fluoride, tetramethylammonium fluoride (TMAF), tetraethylammonium fluoride (TEAF), tetrabutylammonium fluoride (TBAF) and benzyltrimethylammonium fluoride It may include at least one or more selected from the group consisting of.

According to one embodiment of the present invention, the content of the fluoride compound may be 3% to 15% by weight.

According to one embodiment of the present invention, a surfactant containing an anionic functional group; It may further include.

According to one embodiment of the present invention, the surfactant is polystyrene sulfonate, dioctyl sulfosuccinate, perfluorooctanesulfonate, perfluorobutanesulfonate (perfluorobutanesulfonate), alkyl-aryl ether phosphate, alkyl ether phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether phosphate ether phosphate), polyoxyethylene styrenated aryl sulfate, polyoxyethylene styrenated aryl phosphate, polyaryl ether sulfate, polyaryl ether phosphate ), isoalkyl alcohol polyoxyethylene ether sulfate, isoalkyl alcohol polyoxyethylene ether phosphate, polyoxyethylene alkyl ether sulfonic ester, Polyoxyethylene alkyl phenyl ether phosphonic ester, polyoxyethylene styrenated aryl sulfonic ester, styrenated polyoxyethylene aryl phosphonic Polyoxyethylene styrenated aryl phosphonic ester, polyaryl ether sulfonic ester, polyaryl ether phosphonic ester, isoalkyl alcohol polyoxyethylene ether sulfonic ester sulfonic ester) and isoalkyl alcohol polyoxyethylene ether phosphonic ester.

According to one embodiment of the present invention, the content of the surfactant may be 0.05% by weight to 5% by weight.

According to an embodiment of the present invention, the cleaning liquid composition may have an etching rate of 40 Å/min or more for an oxide film and an etching rate of 1 Å/min or more for a nitride film.

According to one embodiment of the present invention, after the CMP process of a semiconductor wafer using a polishing slurry, the film surface of the wafer is etched to facilitate the removal of residual particles and organic matter, and a cleaning liquid composition capable of improving surface defects can provide.

According to one embodiment of the present invention, the present invention can provide a cleaning liquid composition capable of smoothly performing subsequent processes by removing surface defects on a silicon oxide film and/or a silicon nitride film and dissolving abrasive particles of the polishing slurry.

According to one embodiment of the present invention, the present invention can provide a cleaning solution composition applicable to a film-quality cleaning solution that is vulnerable to strong acid and that enables HF-free and SPM-free processes, shortens the process time.

The present invention provides a cleaning liquid composition containing a phosphoric acid-based compound capable of selectively etching a nitride film, which can facilitate the removal of defects by dissolving ceria and etching the surface of a silicon nitride film in a subsequent cleaning process after polishing with ceria particles. .

In the following, embodiments are described in detail. However, since various changes can be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents or substitutes to the embodiments are included within the scope of rights.

Terms used in the examples are used only for descriptive purposes and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the corresponding component is not limited by the term. When an element is described as being “connected”, “coupled” or “connected” to another element, the element may be directly connected or connected to the other element, but there may be another element between the elements. It should be understood that may be "connected", "coupled" or "connected".

Components included in one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, descriptions described in one embodiment may be applied to other embodiments, and detailed descriptions will be omitted to the extent of overlap.

The present invention relates to a cleaning liquid composition and a cleaning method during a semiconductor process using the same.

Semiconductors are manufactured through numerous processes, and semiconductor manufacturing processes are being developed in the direction of engraving finer circuits on wafers, so a process of removing defects can be performed in the middle of each process to maintain constant semiconductor quality. . In particular, the chemical mechanical polishing (CMP) process grinds the surface layer of a sample by injecting polishing slurry and rubbing the polishing pad and the surface of the sample, improving the flatness of the machined surface, making the surface of the thin film uniform, and It is a necessary process to selectively remove concave-convex protrusions and uniformly remove the surface of heterogeneous materials.

The CMP process applies an abrasive slurry containing abrasive particles on a silicon wafer and then physically rubs it with a polishing pad to have an even surface. In the case of constituting, it may be performed to flatten by removing non-uniform steps on the wafer surface. However, if the polishing slurry sprayed for the CMP process remains on the surface, it may cause defects during the subsequent process of the wafer, so that the polishing slurry and the abrasive particles included in the polishing slurry need to be cleaned after the surface planarization of the wafer.

According to one embodiment of the present invention, the cleaning liquid composition comprises an organic acid; phosphoric acid compounds; And a nitrate compound; may include. For example, the cleaning liquid composition is a post-CMP cleaning liquid composition applied after a CMP process, and can dissolve abrasive particles (eg, ceria particles) to remove abrasive slurry and/or abrasive particles remaining on a wafer surface.

According to one embodiment of the present invention, the organic acid has a function as a solubilizing agent and may include, for example, an organic acid containing at least one of organic acids containing a carboxyl group.

As an example of the present invention, the organic acid may include an organic acid containing a carboxyl group. The organic acid containing the carboxyl group may include one to three carboxyl functional groups. In the organic acid containing the carboxyl group, hydrogen at the terminal of the carboxyl group is dissociated in the cleaning liquid composition to supply hydrogen cations and electrons. The electrons supplied in this way can be used for a reduction reaction of abrasive particles (eg, ceria particles). For example, when a CMP process is performed using a ceria slurry containing ceria particles, a cerium reduction reaction (Ce(IV)+e ^- →Ce(III)) may occur by electrons supplied from a carboxyl group terminal. That is, as a component containing a carboxyl group, it can be dissociated as R-COOH→R-COO-+H++e to supply H+ ions and electrons “e”. The supplied electrons are used for the ceria reduction reaction [Ce(IV)+e → Ce(III)], and the reduced Ce(III) ions are dissolved as Ce(OH) ₃ .

As an example of the present invention, the organic acid containing the carboxyl group is citric acid, lactic acid, gluconic acid, maleic acid, malic acid, malonic acid acid, adipic acid, succinic acid, tartaric acid, glutaric acid, glycolic acid, aspartic acid, itaconic acid ), glutamic acid, tricarballylic acid, pimelic acid, suberic acid, sebacic acid, stearic acid, pyruvic acid , acetoacetic acid, glyoxylic acid, azelaic acid, fumaric acid, glutaconic acid, traumatic acid, muconic acid , aconitic acid, carballylic acid, tribasic acid, mellitic acid, isocitric acid, citric acid, lactic acid, gluconic acid, maleic acid, ascorbic acid, iminoacetic acid, oxalic acid, pyrogallic acid, formic acid, acetic acid ( acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, hep heptanoic acid, caprylic acid, nonanoic acid, decanoic acid, undecylenic acid, lauric acid, tridecylic acid ), at least one selected from the group consisting of myristic acid, pentadecanoic acid, and palmitic acid.

As an example of the present invention, the content of the organic acid may be 1% to 5% by weight. The content of the organic acid can be calculated based on the total weight of the cleaning liquid composition, and when the organic acid is used in an amount of less than 1% by weight based on the total weight of the cleaning liquid composition, the supply of hydrogen cations and electrons dissociated at the terminal of the organic acid is insufficient. It may be difficult for the reaction to occur sufficiently. On the other hand, when the organic acid is used in an amount of more than 5% by weight based on the total weight of the cleaning liquid composition, the solubility of the cleaning liquid decreases and precipitation may occur.

As an example of the present invention, based on the total weight of the cleaning liquid composition, the organic acid is 1% to 4% by weight, 1% to 3% by weight, 1% to 2% by weight, 2% to 5% by weight, 2% by weight % to 4% by weight, 2% to 3% by weight, 3% to 5% by weight, 3% to 4% by weight or 4% to 5% by weight.

According to one embodiment of the present invention, the phosphoric acid-based compound is an acidic substance containing phosphate, and is dissociated into phosphate and H+ ions. The dissociated phosphate, acting together with nitrate and organic acid, can selectively act on the silicon nitride film to promote etching.

As an example of the present invention, the phosphoric acid-based compound is included in 10% to 20% by weight in the cleaning liquid composition, which is when the phosphoric acid-based compound is included in less than 10% by weight in the state where the organic acid and the sulfur compound are added Etching of the nitride film does not proceed, and when it exceeds 20% by weight, it can act as a passivator for the oxide film.

As an example of the present invention, the phosphoric acid-based compound may be an inorganic phosphoric acid-based compound, and phosphoric acid, pyrophosphoric acid, polyphosphoric acid, metaphosphoric acid, hypophosphoric acid ( Hypophosphoric acid, Triphosphoric acid, Phosphorus trioxide Phosphorus pentoxide, Peroxymonophosphoric acid, Peroxydiphosphoric acid, Phosphorous acid, Hypophosphorous acid ), phosphate, phosphonic acid (phosphonic acid, RPO ₃ H ₂ ), and at least one selected from the group consisting of salts thereof, wherein the salt is an inorganic or organic salt, for example, sodium salts, potassium salts, magnesium salts or ammonium salts, and the like.

According to an embodiment of the present invention, the nitrate compound may include at least one selected from the group consisting of nitric acid, ammonium nitrate, and sodium nitrate. The nitrate compound may be an inorganic acid containing a nitric acid group. According to one embodiment, the nitrate compound may be dissociated into nitrate and hydrogen cations in the cleaning liquid composition, and the dissociated nitrate may dissolve abrasive particles (eg, ceria particles). For example, ceria particles can be reduced to Ce(III) ions, react with a nitrate compound to form Ce(III)nitrate and/or Ce(OH) ₃ , and can be dissolved into a cleaning liquid composition.

As an example of the present invention, the nitrate compound is included in 1% to 5% by weight in the cleaning liquid composition, and when used in less than 1% by weight, performance is insufficient in evaluating turbidity (Ce Dissolution), and 5% by weight If it is used more than that, it is classified as a toxic substance and its use is restricted.

According to one embodiment of the present invention, the composition further comprises a sulfur compound, the sulfur compound can function as a dissolving agent for abrasive particles, and at least one functional group selected from the group consisting of a sulfonic acid group, a carboxyl group and an amino group can include

As an example of the present invention, the sulfur compound dissolves abrasive particle ions (eg, cerium ions) and adsorbs remaining particle particles to improve cleaning power and surface defect improvement after cleaning. For example, an acid containing sulfur is dissociated into sulfate and H+ ions, and the sulfate dissociated from the sulfur compound combines with cerium ions to form Ce(IV)sulfate and/or Ce(OH) ₄ . and can be dissolved in the cleaning liquid composition.

As an example of the present invention, the sulfur compound may be an acidic material containing sulfur. According to one embodiment, the sulfur compound is sulfosuccinic acid, sulfoacetic acid, 2-phenyl-2-sulfoacetic acid, 2-(2-adamane) Tyl)-2-sulfoacetic acid (2-(2-adamantyl)-2-sulfoacetic acid), salicylic acid, sulfosalicylic acid, sulfobenzoic acid, sulfophthalic acid, sulfophthalic acid sulfoisophthalic acid, sulfoglucuronic acid, cysteic acid, sulfuric acid, methanesulfonic acid, sulfamic acid and sulfanilic acid ), which may include at least one selected from the group.

As an example of the present invention, the sulfur compound may include at least one of an inorganic acid and/or an organic acid having sulfur or a sulfur-containing functional group in a molecule.

As an example of the present invention, the sulfur compound is sulfuric acid, thiosulfuric acid (H ₂ S ₂ O ₃ ), sulfide, bisulfide (RSS-R'), hydrogen sulfide ( hydrogen sulfide (H ₂ S), sulfur trioxide (SO ₃ ), sulfamic acid, sulfenic acid (RSOH), sulfinic acid (RSO(OH)), thiosulfonic acid ( RSO₂SH), thiocarboxylic acid (RC(S)OH), sulfate, sulfonate (sulfonate, R-SO₃, R-SO₃-R'), a salt thereof, and an anhydride thereof. may include one or more, wherein R and R' are each hydrogen, hydrocarbon (e.g., alkyl having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, and substituted or unsubstituted aralkyl (For example, benzyl group, phenyl group, toluenyl group, naphthalene group, etc.), and selected from esters, etc., but are not limited thereto, and will be described in more detail below. For example, it may be a sodium salt, potassium salt, magnesium salt or ammonium salt.

As an example of the present invention, the sulfonate may be a salt or ester of the sulfonic acid, for example, an alkyl sulfonate, an arylsulfonate, or an alkyl aryl sulfonate. sullfonate), alkylether sulfonate, polystyrene sulfonate, alkanesulfonate, α-olefin sulfonate, dodecylbenzenesulfonate and alkylbenzene sulfonate (alkylbenzenesulfonate) and the like. Here, alkyl and alkane are selected from 1 to 20 carbon atoms, and the aryl may be selected from 6 to 30 carbon atoms.

As an example of the present invention, the sulfur compound may include an organic acid including a sulfonyl group, for example, an organic sulfonic acid. The organic sulfonic acid may be an alkanesulfonic acid, an alkanolsulfonic acid, sulfosuccinic acid, or an aromatic sulfonic acid. The alkanesulfonic acid may be represented by C _n H _2n+1 SO ₃ H (eg, n = 1 to 20), and examples include methanesulfonic acid, ethanesulfonic acid, 1-propanesulfonic acid, and 2-propanesulfonic acid. , 1-butanesulfonic acid, 2-butanesulfonic acid, and pentanesulfonic acid.

For example, the alkanolsulfonic acid may be represented by C _m H _2m+1 -CH(OH)-C _p H _2p -SO ₃ H (eg, m = 0 to 10, p = 1 to 10). It can be, for example, 2-hydroxyethane-1-sulfonic acid (isethionic acid), 2-hydroxypropane-1-sulfonic acid (2-propanolsulfonic acid), 3-hydroxypropane-1-sulfonic acid, 2- hydroxybutane-1-sulfonic acid, 2-hydroxypentane-1-sulfone, 1-hydroxypropane-2-sulfonic acid, 4-hydroxybutane-1-sulfonic acid and 2-hydroxyhexane-1-sulfonic acid, etc. .

For example, the aromatic sulfonic acid is benzenesulfonic acid, alkylbenzenesulfonic acid, aminobenzenesulfonic acid, nitrobenzenesulfonic acid, sulfobenzoic acid, hydroxybenzenesulfonic acid, toluenesulfonic acid (eg, p-Toluenesulfonic acid), phenolsulfonic acid, naphthalenesulfonic acid , alkylnaphthalenesulfonic acid, naphtholsulfonic acid, xylenesulfonic acid, cresolsulfonic acid, sulfosalicylic acid (5-sulfosalicylic acid), polystyrenesulfonic acid, diphenylamine-4-sulfonic acid, and the like. Here, alkyl may be selected from 1 to 20 carbon atoms.

As an example of the present invention, the sulfur compound is preferably methanesulfonic acid, butanesulfonic acid, sulfamic acid, sulfosuccinic acid, sulfosalicylic acid, sulfobenzoic acid At least one of sulfobenzoic acid, toluenesulfonic acid, and polystyrenesulfonic acid may be used.

As an example of the present invention, the sulfur compound may be used by mixing two or three different types. These can be classified according to molecular weight and use, respectively. As a result, the solubility of metal ions remaining on the surface can be increased, and the effect of removing residual contaminants can be increased.

As an example of the present invention, the sulfur compound is included in 10% to 20% by weight in the cleaning liquid composition, and when used in less than 10% by weight, performance is insufficient when evaluating turbidity (Ce Dissolution), and 20% by weight If it exceeds , the solubility of the cleaning solution is reduced and the possibility of precipitation is high.

According to one embodiment of the present invention, the cleaning liquid composition may further include a fluoride compound. The fluoride compound may be a fluorine ion-containing compound, that is, an ionic fluoride compound. The fluoride compound acts as an etchant and an oxidizing agent, and may help dissolve abrasive particles, abrasive particle-derived dispersions, etc. remaining after the polishing process in water in the form of a hydrate. The fluoride compound may facilitate the removal of surface defects by giving an etching effect to the polished surface once more in a cleaning process after polishing.

As an example of the present invention, the fluoride compound is hydrofluoric acid, ammonium fluoride, ammonium bifluoride, ammonium silicofluoride, sodium fluoride ), barium fluoride, calcium fluoride, magnesium fluoride, potassium fluoride, aluminum fluoride, aminobenzotrifluoride , boron trifluoride, cobalt(II) fluoride, tetramethylammonium fluoride (TMAF), tetraethylammonium fluoride (TEAF), tetrabutylammonium fluoride (TBAF) and benzyltrimethylammonium fluoride ) may include at least one selected from the group consisting of.

As an example of the present invention, the fluoride compound can be dissociated into an ammonium cation and a fluoride anion, and the dissociated fluoride anion combines with a hydrogen cation (H + ) supplied through an acid to form hydrofluoric acid to form a surface of a wafer Etching can help.

As an example of the present invention, the content of the fluoride compound may be 3% to 15% by weight. According to one embodiment, based on the total weight of the cleaning liquid composition, the fluoride compound is 3% to 10% by weight, 3% to 7% by weight, 5% to 15% by weight, 7% to 15% by weight, 10% to 15% or 7% to 12% by weight.

As an example of the present invention, when the fluoride compound is less than 3% by weight based on the total weight of the cleaning liquid composition, the etching effect is insignificant during cleaning, resulting in reduced lift off performance or reduced surface defect removal function, and low performance when evaluating turbidity This may occur or hydrate may not be produced, and if it exceeds 15% by weight, film loss occurs or surface defects are rather increased due to the remaining fluoride compound, and use is restricted because it is classified as a toxic substance.

As an example of the present invention, a weight ratio (w/w) of the organic acid:the nitrate compound:the phosphoric acid compound in the cleaning liquid composition may be 1:0.1 to 2:2 to 7. When it is within the above range, selective etching of the nitride film is possible, and thus defect reduction and cleaning effect can be improved. The phosphoric acid-based compound acts together with the organic acid and the nitrate compound to increase the etching effect of the nitride film, and when there is no one of them, selective etching of the nitride film does not proceed.

As an example of the present invention, the weight ratio of the organic acid to the sulfur compound may be 1:3 to 1:6 weight ratio (w/w). Even when two or three sulfur compounds are mixed, the total amount of the sulfur compounds may be included within the above range. According to one embodiment, when the weight ratio is less than 3 times, the solubility of abrasive particles (eg, cerium particles) in the cleaning liquid composition may be low. In addition, when the weight of the sulfur compound compared to the weight of the organic acid exceeds 6 times, the solubility of the sulfur compound is low, and precipitation and/or aggregation may occur in the cleaning liquid composition.

As an example of the present invention, the weight ratio (w / w) of the sulfur compound: the phosphoric acid-based compound is 1: 0.5 to 1: 2; or 1: 0.5 to 1: 1.9, and the weight ratio (w/w) of the nitrate: the phosphoric acid-based compound may be 1: 2 to 1: 25. When included within the above range, excellent cleaning function and defect removal rate can be provided.

According to one embodiment of the present invention, the cleaning composition may further include a surfactant, and the surfactant may be a surfactant containing an anionic functional group.

As an example of the present invention, the surfactant may adsorb onto the surface of the wafer to modify the surface. A silicon oxide layer and/or a silicon nitride layer may be formed on the surface of the wafer, and since the silicon oxide layer and/or the silicon nitride layer has a positive charge, contaminant particles may easily adhere thereto. However, the surface of the oxide film and/or the nitride film can be negatively charged by binding the surfactant to the surface, and as the zeta potential is lowered to a negative value, adsorption of contaminant particles can be prevented.

As an example of the present invention, the content of the surfactant may be 0.05% to 5% by weight. According to one embodiment, when less than 0.05% by weight of the surfactant is used based on the total weight of the cleaning liquid composition, the entire surface of the membrane may be modified, and when it is included in more than 5% by weight, the cleaning liquid composition may become cloudy. there is.

As an example of the present invention, the surfactant is polystyrene sulfonate, dioctyl sodium sulfosuccinate, perfluorooctanesulfonate, perfluorobutanesulfonate , alkyl-aryl ether phosphate, alkyl ether phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether phosphate , polyoxyethylene styrenated aryl sulfate, polyoxyethylene styrenated aryl phosphate, polyaryl ether sulfate, polyaryl ether phosphate, iso isoalkyl alcohol polyoxyethylene ether sulfate, isoalkyl alcohol polyoxyethylene ether phosphate, polyoxyethylene alkyl ether sulfonic ester, polyoxyethylene Alkyl phenyl ether phosphonic ester (polyoxyethylene alkyl phenyl ether phosphonic ester), styrenated polyoxyethylene aryl sulfonic ester (polyoxyethylene styrenated aryl sulfonic ester), styrenated polyoxyethylene aryl phosphonic ester ( polyoxyethylene styrenated aryl phosphonic ester, polyaryl ether sulfonic ester, polyaryl ether phosphonic ester, isoalkyl alcohol polyoxyethylene ether sulfonic ester ) and at least one selected from the group consisting of isoalkyl alcohol polyoxyethylene ether phosphonic ester.

As an example of the present invention, the pH of the cleaning liquid composition may be 3 to 6, 3 to 5, or 4 to 5.

According to one embodiment of the present invention, the cleaning liquid composition for CMP including at least one abrasive particle selected from the group consisting of silica, ceria, zirconia, alumina, titania, barium titanate, germania, mangania, and magnesia. It may be to dissolve remaining abrasive particles after polishing with the slurry. Preferably, after polishing using a CMP slurry containing ceria particles, remaining ceria particles may be dissolved.

As an example of the present invention, the abrasive particles may be reduced and dissolved in a cleaning liquid composition. For example, in the case of reduced cerium particles (eg, Ce(III)), it may be dissolved in the form of Ce(OH) ₃ in the cleaning liquid composition.

According to an embodiment of the present invention, the cleaning liquid composition may clean the surface of a semiconductor device wafer including a nitride film, an oxide film, or both after polishing. For example, the nitride layer may be a silicon nitride layer, and the oxide layer may be a silicon oxide layer.

As an example of the present invention, after cleaning with the cleaning liquid composition, defects of the silicon oxide layer may be reduced by 10% or more compared to the standard, and defects of the silicon nitride layer may be reduced by 15% or more compared to the standard.

As an example of the present invention, the cleaning liquid composition may have an etching rate of 40 Å/min or more, or 70 Å/min or more for a silicon oxide film, and an etching rate for a nitride film of 1 Å/min or more.

Hereinafter, the present invention will be described in more detail by examples and comparative examples.

However, the following examples are only for illustrating the present invention, and the content of the present invention is not limited to the following examples.

Examples and Comparative Examples

As shown in Table 1 below, cleaning liquid compositions according to Examples and Comparative Examples may be prepared. The cleaning liquid composition may include an organic acid, a phosphoric acid compound, a nitrate compound, and a fluoride compound, and the pH may be adjusted as shown in Table 1 below.

At this time, citric acid or gluconic acid may be used as the organic acid, nitric acid may be used as the nitrate compound, and ammonium fluoride may be used as the fluoride compound, Phosphoric acid-based compounds include phosphoric acid (Examples 1 to 3), metaphosphoric acid (Examples 4 to 6), pyrophosphoric acid (Examples 7 to 8), or phosphorus pentoxide (Phosphorus pentoxide, Examples 9 to 10) were used,

Comparative Example 1

It is a commercially available SPM (Sulfuric Peroxide Mixture) cleaning solution.

Comparative Example 2

It is a commercially available SC1 (Standard Clean-1, APM) cleaning solution.

* In Comparative Examples and Examples, the solvent is deionized water in a residual amount or an appropriate amount.

division Chemical Concentration (%) pH organic acid nitrate compounds phosphoric acid compound fluoride compounds Example 1 3 One 10 13 4.6 Example 2 3 One 15 13 4.4 Example 3 3 One 20 13 4.1 Example 4 3 4.5 10 13 4.2 Example 5 3 4.5 15 13 4.0 Example 6 3 4.5 20 13 3.8 Example 7 3 One 10 13 4.3 Example 8 3 One 20 13 4.1 in practice 9 3 One 10 13 4.5 Example 10 3 One 20 13 4.2 Comparative Example 1 SPM - Comparative Example 2 SC1 - Comparative Example 3 3 One - 13 4.7 Comparative Example 4 3 - 10 13 4.7 Comparative Example 5 3 One 5 13 5.1 Comparative Example 6 3 One 25 13 3.9

Experimental Example 2: Defect measurement

Defects may be measured after surface treatment or cleaning using the cleaning liquid compositions according to Examples and Comparative Examples in Table 1 above. To this end, first, the wafer was polished through a CMP process for 10 seconds under a pressure of 2 psi using a ceria slurry having an average particle diameter of 100 nm, and the surface of the wafer was polished using a brush using the cleaning composition according to Examples and Comparative Examples. After cleaning, secondary cleaning with SC-1 can remove surface defects. After cleaning the wafer, the number of defects is checked using KLA-Tencor's defect measuring equipment, and the defect removal rate is calculated as in Equation 1 below, and the results can be shown in Table 2 below. At this time, the standard cleaning may be based on Comparative Example 1.

[Equation 1]

Defect removal rate (%) = {(Number of defects-Number of defects in Comparative Example 2)/Number of bonds in Comparative Example 2}×100

division Silicon oxide (≥63 nm) Silicon nitride (≥52 nm) number of defects Defect removal rate (%) number of defects Defect removal rate (%) Example 1 85 -47% 220 -27% Example 2 114 -29% 218 -27% Example 3 144 -10% 197 -34% Example 4 98 -39% 238 -21% Example 5 127 -21% 210 -30% Example 6 143 -11% 201 -33% Example 7 95 -41% 216 -28% Example 8 140 -13% 202 -33% Example 9 102 -36% 221 -26% Example 10 138 -14% 195 -35% Comparative Example 2 160 - 300 - Comparative Example 3 79 -51% 310 3% Comparative Example 4 115 -28% 329 10% Comparative Example 5 88 -45% 318 6% Comparative Example 6 212 33% 276 -8%

* Compositions of Examples and Comparative Examples were diluted 20 times with deionized water, respectively, and room temperature (RT) defect removal rates were measured.

Referring to Table 3, when the cleaning liquid composition according to the embodiment is used, the number of defects is significantly reduced compared to standard cleaning (eg, cleaning using the cleaning liquid composition according to Comparative Example 1), resulting in significant defects in the silicon oxide film and the silicon nitride film. It can be confirmed that the removal rate is exhibited, and it can be confirmed that an excellent surface defect improvement effect is exhibited. The cleaning liquid composition according to the embodiment reduces defects in the silicon oxide film by 10% or more and at the same time reduces defects in the silicon nitride film by 20% or more, while the cleaning liquid composition according to the comparative example reduces the number of defects in the silicon nitride film It can be confirmed that the defect removal rate is increased or the defect removal rate is low.

Experimental Example 3: Etching rate measurement

After measuring values before (Pre) and after (Post) Etch using an elipsometer, the etching rate was calculated by dividing by Etch time (Pre-Post)/Etch time = Etch rate method. The results are shown in Table 3.

division Etch rate (Å/min) Oxide Nitride Example 1 75.4 1.1 Example 2 75.2 1.5 Example 3 75.1 1.8 Example 4 75.2 5.1 Example 5 72.8 4.8 Example 6 70.6 4.1 Example 7 74.2 1.2 Example 8 76.3 1.5 Example 9 73.5 1.3 Example 10 71.7 1.7 Comparative Example 1 0.0 0.0 Comparative Example 2 0.0 0.0 Comparative Example 3 75.3 0.3 Comparative Example 4 75.4 0.2 Comparative Example 5 75.5 0.6 Comparative Example 6 21.7 6.5

* Compositions of Examples and Comparative Examples were diluted 20 times with deionized water, respectively, and room temperature (RT) etching rates were measured.

Referring to Table 3, in the cleaning liquid composition of the embodiment, the etching rate of the nitride film is increased by adding a phosphoric acid-based compound capable of selectively etching the wafer film quality, which provides excellent cleaning function and defect removal rate for the oxide film and the nitride film. can

Although the embodiments have been described as above, those skilled in the art may apply various technical modifications and variations based on the above. For example, the described techniques may be performed in an order different from the method described, and/or the components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

Claims (17)

organic acids;
phosphoric acid compounds; and
nitrate compounds;
including,
Post-CMP cleaning liquid composition.
According to claim 1,
The organic acid is an organic acid containing at least one carboxyl group,
The organic acid is citric acid, lactic acid, gluconic acid, maleic acid, malic acid, malonic acid, adipic acid , succinic acid, tartaric acid, glutaric acid, glycolic acid, aspartic acid, itaconic acid, glutamic acid, trica tricarballylic acid, pimelic acid, suberic acid, sebacic acid, stearic acid, pyruvic acid, acetoacetic acid, glyoxyl Glyoxylic acid, azelaic acid, fumaric acid, glutaconic acid, traumatic acid, muconic acid, aconitic acid, carbal carballylic acid, tribasic acid, mellitic acid, isocitric acid, citric acid, lactic acid, gluconic acid, maleic acid ( maleic acid), ascorbic acid, iminoacetic acid, oxalic acid, pyrogallic acid, formic acid, acetic acid, propionic acid, Butyric acid, valeric acid, hexanoic acid, heptanoic acid, caprylic acid Caprylic acid, nonanoic acid, decanoic acid, undecylenic acid, lauric acid, tridecylic acid, myristic acid , Pentadecanoic acid (pentadecanoic acid) and palmitic acid (palmitic acid) containing at least one selected from the group consisting of,
Post-CMP cleaning liquid composition.
According to claim 1,
The content of the organic acid,
1% to 5% by weight of the cleaning liquid composition,
Post-CMP cleaning liquid composition.
According to claim 1,
The phosphate-based compound,
Phosphoric acid, Pyrophosphoric acid, Polyphosphoric acid, Metaphosphoric acid, Hypophosphoric acid, Triphosphoric acid, Phosphorus trioxide, Phosphorus pentoxide ), peroxymonophosphoric acid, peroxydiphosphoric acid, phosphorous acid, hypophosphorous acid, phosphate, phosphonic acid (RPO ₃ H ₂ ) and their To include at least one or more selected from the group consisting of salts,
Post-CMP cleaning liquid composition.
According to claim 1,
The phosphate-based compound,
10% to 20% by weight of the cleaning liquid composition,
Post-CMP cleaning liquid composition.
According to claim 1,
The nitrate compound,
containing at least one selected from the group consisting of nitric acid, ammonium nitrate and sodium nitrate,
Post-CMP cleaning liquid composition.
According to claim 1,
The weight ratio of the organic acid: the nitrate compound: the phosphoric acid compound is 1: 0.1 to 2: 2 to 7,
Post-CMP cleaning liquid composition.
According to claim 1,
The cleaning liquid composition,
sulfur compounds; Including more,
The weight ratio of the organic acid to the sulfur compound is 1: 3 to 1: 6,
The weight ratio of the sulfur compound: the phosphoric acid compound is 1: 0.5 to 1: 2,
Post-CMP cleaning liquid composition.
According to claim 8,
The sulfur compound,
Sulfuric acid, thiosulfuric acid (H ₂ S ₂ O ₃ ), sulfide, bisulfide (RSS-R'), hydrogen sulfide (H ₂ S), sulfur trioxide , SO ₃ ), sulfenic acid (RSOH), sulfinic acid (RSO(OH)), thiosulfonic acid (RSO₂SH), thiocarboxylic acid (RC(S)OH), sulfate ( sulfate), sulfonates (sulfonate, R-SO₃, R-SO₃-R'), organic sulfonic acids, salts of one or more of them, and at least one selected from the group consisting of anhydrides of one or more of them. will,
Post-CMP cleaning liquid composition.
According to claim 8,
The organic sulfonic acid,
Containing at least one selected from the group consisting of alkanesulfonic acid, alkanolsulfonic acid, sulfosuccinic acid and aromatic sulfonic acid,
Post-CMP cleaning liquid composition.
According to claim 8,
The sulfur compound,
10% to 20% by weight of the cleaning liquid composition,
Post-CMP cleaning liquid composition.
According to claim 1,
fluoride compounds;
Including more,
The fluoride compound,
Hydrofluoric acid, ammonium fluoride, ammonium bifluoride, ammonium silicofluoride, sodium fluoride, barium fluoride, calcium fluoride Calcium fluoride, magnesium fluoride, potassium fluoride, aluminum fluoride, aminobenzotrifluoride, boron trifluoride, cobalt ( Ⅱ) Contains at least one selected from the group consisting of fluoride (cobalt(II) fluoride), TMAF (tetramethylammonium fluoride), TEAF (tetraethylammonium fluoride), TBAF (tetrabutylammonium fluoride), and benzyltrimethylammonium fluoride to do,
Post-CMP cleaning liquid composition.
According to claim 12,
The content of the fluoride compound,
3% to 15% by weight,
Post-CMP cleaning liquid composition.
According to claim 1,
Surfactants containing anionic functional groups;
Which further includes
Post-CMP cleaning liquid composition.
According to claim 14,
The surfactant is
polystyrene sulfonate, dioctyl sulfosuccinate, perfluorooctanesulfonate, perfluorobutanesulfonate, alkyl-aryl ether phosphate phosphate), alkyl ether phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether phosphate, polyoxyethylene styrenated polyoxyethylene aryl sulfate aryl sulfate, polyoxyethylene styrenated aryl phosphate, polyaryl ether sulfate, polyaryl ether phosphate, isoalkyl alcohol polyoxyethylene ether sulfate ether sulfate), isoalkyl alcohol polyoxyethylene ether phosphate, polyoxyethylene alkyl ether sulfonic ester, polyoxyethylene alkyl phenyl ether phosphonic ester phosphonic ester), styrenated polyoxyethylene aryl sulfonic ester (polyoxyethylene styrenated aryl sulfonic ester), styrenated polyoxyethylene aryl phosphonic ester (polyoxyethylene styrena ted aryl phosphonic ester, polyaryl ether sulfonic ester, polyaryl ether phosphonic ester, isoalkyl alcohol polyoxyethylene ether sulfonic ester And isoalkyl alcohol polyoxyethylene ether phosphonic ester (isoalkyl alcohol polyoxyethylene ether phosphonic ester) comprising at least one selected from the group consisting of,
Post-CMP cleaning liquid composition.
According to claim 14,
The content of the surfactant,
0.05% by weight to 5% by weight,
Post-CMP cleaning liquid composition.
According to claim 1,
The cleaning liquid composition,
The etching rate for the oxide film is 40 Å / min or more, and the etching rate for the nitride film is 1 Å / min or more,
Post-CMP cleaning liquid composition.