JPH0967688A - Surface-treating composition of substrate and surface treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a surface-treating composition capable of preventing the contamination of the surface of a substrate with the metallic impurities from the composition and stably attaining an extremely clean substrate surface and to provide the surface treatment of the substrate using the composition. SOLUTION: This surface-treating composition contains a complexing agent in a liq. medium as a metal deposition preventive agent. The composition consists of at least one kind of complexing agent selected from the complexing agents (e.g. tylon and catechol) having a ring skeleton in the molecular structure and having >=1 OH group and/or O-group linked to the carbon atom constituting the ring and the complexing agents (e.g. HF and HCl) having >=1 halogen, sulfur or carbon atom as the donor atom in the molecular structure. A substrate is surface-treated by using the composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment composition and a method of surface treatment of a substrate using the composition. More specifically, when the substrate is subjected to surface treatment using a surface treatment composition containing a liquid medium as a main component, contamination of the surface treatment composition from the surface treatment composition to the substrate surface is prevented, and the substrate is extremely clean and stable. The present invention relates to a surface treatment composition capable of achieving various substrate surfaces and a method of treating the surface of a substrate using the same.

[0002]

2. Description of the Related Art With the high integration of various devices typified by ultra LSI, TFT liquid crystal and the like, the requirement for cleaning the surface of a substrate used in the devices is becoming more and more severe. Contamination with various substances is one of the obstacles to cleaning, and among the contaminations, metal contamination in particular degrades the electrical characteristics of the device, and in order to prevent such degradation, the metal on the substrate surface on which the device is formed It is necessary to reduce the concentration of impurities as much as possible. Therefore, cleaning of the substrate surface with a cleaning agent is generally performed.

Heretofore, as cleaning agents of this type, aqueous solutions of water, electrolytic ion water, acids, alkalis, oxidizing agents, surfactants and the like, organic solvents and the like have generally been used. The cleaning agent is required to have an extremely low level of impurity concentration in the cleaning agent in order to prevent reverse contamination by metal impurities from the cleaning agent to the substrate as well as excellent cleaning performance. In order to satisfy such requirements, high purification of semiconductor chemicals used for cleaning is promoted, and the metal impurity concentration contained in the chemicals immediately after purification has reached a level which is difficult to detect by the current analysis technology. Thus, it is still difficult to achieve a highly clean substrate surface despite the fact that impurities in the cleaning agent have reached difficult levels of detection, because metal impurities removed from the substrate in the cleaning tank are This is because it is inevitable to contaminate the detergent itself. That is, the metal impurities once desorbed from the substrate surface mix in the cleaning agent to contaminate the cleaning agent, and the metal impurities from the contaminated cleaning agent adhere to the substrate (reverse contamination).

In the semiconductor cleaning process, cleaning with [ammonia + hydrogen peroxide + water] solution (SC-1 cleaning)
(RCA Review, p. 187-206, June (1970), etc.) are widely used. This washing is usually performed at 40 to 90 ° C.
The composition ratio in the solution is usually (30% by weight aqueous ammonia): (31% by weight aqueous hydrogen peroxide): (water) = 0.0
About 5: 1: 5 to 1: 1: 5. However, while this cleaning method has high particle removal ability and organic matter removal ability, when a very small amount of metal such as Fe, Al, Zn, or Ni is present in the solution, it adheres to the substrate surface and causes reverse contamination. There is. For this reason, in the semiconductor cleaning process, usually [ammonia + hydrogen peroxide + water]
After solution cleaning, cleaning with an acidic cleaner such as [hydrochloric acid + hydrogen peroxide + water] solution cleaning (SC-2 cleaning) is performed to remove metal contamination on the substrate surface. Therefore, in order to obtain a highly clean surface efficiently and stably in the cleaning step, a technique for preventing such reverse contamination has been required.

Further, the problem that metal impurities in the liquid adhere to the substrate surface is the substrate using a solution such as alkaline etching of a silicon substrate or etching of a silicon oxide film with dilute hydrofluoric acid as well as a cleaning step. It is a big problem in the surface treatment process in general. In the dilute hydrofluoric acid etching process, if there is a noble metal impurity such as Cu or Au in the liquid, it adheres to the silicon surface and the electrical characteristics of the device such as carrier lifetime are significantly degraded. In addition, in the alkali etching step, if there are trace metal impurities such as Fe and Al in the liquid, these easily adhere to the substrate surface, which adversely affects the quality. Therefore, a technique for preventing such contamination in the surface treatment process with a solution is also strongly demanded.

In order to solve these problems, a complexing agent such as a chelating agent is added to the surface treatment agent to capture metal impurities in the liquid as a stable water-soluble complex and prevent adhesion to the substrate surface. A method has been proposed. For example, Japanese Patent Laid-Open No. 50-
In 158281, an aqueous solution of tetraalkyl ammonium hydroxide, ammonium cyanide or ethylene diamine
It has been proposed to add a complexing agent such as acetic acid (EDTA) to prevent adhesion of metal impurities to the surface of the semiconductor substrate. JP-A-3-219000 is a chelating agent such as catechol or tiron, JP-A-5-275405 is a phosphonic acid-based chelating agent or a complexing agent such as condensed phosphoric acid, JP-A-6-16
In 3495, a complexing agent such as a hydrazone derivative is added to an alkaline cleaning solution such as [ammonia + hydrogen peroxide + water] to prevent metal impurities from adhering to the substrate, thereby metal contamination as well as particle and organic contamination. It is proposed to achieve a substrate surface without

However, when these complexing agents are added, although a certain metal (eg, Fe) has an adhesion preventing or removing effect, metals other than Fe which easily contaminate the processing solution and the substrate ( For example, in the case of Al), there is a problem that the effect of the above complexing agent is extremely small, and a sufficient effect can not be obtained even if a large amount of complexing agent is added. Japanese Patent Application Laid-Open No. 6-216098 to solve this problem.
Proposes a method of cleaning the substrate with a [Ammonia + hydrogen peroxide + water] cleaning solution to which a chelating agent such as a phosphonic acid type chelating agent has been added and then rinsing with an aqueous solution of 1 ppm or more of hydrofluoric acid. With a cleaning solution to which a phosphonic acid type chelating agent has been added, Al contamination on the substrate surface can not be sufficiently reduced, so that it is intended to remove Al by etching using a hydrofluoric acid aqueous solution of 1 ppm or more in a later step. As described above, the conventional metal adhesion preventing method is not sufficient in effect, and when it is necessary to clean the substrate, the metal contamination has to be removed in a later step, thereby increasing the number of steps. This has been the cause of increased production costs. Thus, in order to prevent metal impurity contamination from the surface treatment composition to the substrate surface, adhesion prevention is attempted by the addition of various complexing agents, but there is still no sufficient improvement.
Contamination prevention technology has not been achieved yet.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and prevents contamination of metal surfaces from the surface treatment composition to the surface of the substrate, stably and extremely clean the surface of the substrate. It is an object of the present invention to provide a surface treatment composition capable of achieving the above and a surface treatment method of a substrate using the same.

[0009]

SUMMARY OF THE INVENTION According to the present invention, when two or more specific complexing agents are added as a metal adhesion preventing agent to a surface treatment composition, as compared with the case where one complexing agent is used, This is achieved based on the novel finding that the effect of preventing adhesion of metal impurities from the processing solution to the substrate is significantly improved.
That is, the subject matter of the present invention is that, in the surface treatment composition containing a complexing agent as a metal adhesion inhibitor in a liquid medium, the complexing agent has a cyclic skeleton in the molecular structure (group A), and OH groups and / or bonded to the carbon atoms constituting the ring O ^- complexing agent having one or more groups, and (B group) halogen is a donor atom in a molecular structure, at least one selected from sulfur or carbon The surface treatment composition of a substrate comprising at least one complexing agent selected from each group of complexing agents having one or more of the atoms and the surface treatment method of the substrate using this surface treatment composition.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The surface treatment composition of the present invention is characterized in that the composition contains two or more specific complexing agents as a metal adhesion inhibitor. The particular two or more complexing agents consist of one or more complexing agents selected from the group A defined below and one or more complexing agents selected from the group B. In the present invention, the surface treatment composition refers to the cleaning of a substrate,
It is a generic term for surface treatment agents used for the purpose of etching, polishing, film formation and the like.

[0011] The group A of the complexing agent has an annular skeleton in the molecular structure, and OH groups and / or O bonded to the carbon atom of the ring ^- with a complexing agent having at least one group is there. The cyclic skeleton in the molecular structure may be any of cyclic structures corresponding to alicyclic compounds, aromatic compounds or heterocyclic compounds, and one or more of these cyclic skeletons in the molecular structure, and this ring O bonded to the carbon atom that constitutes
It has one or more H groups and / or O 2 ^- groups. Specific examples of such complexing agents include those shown below, but are not particularly limited thereto. Also,
Although specific examples are illustrated as compounds having an OH group, the corresponding salts such as ammonium salts, alkali metal salts and the like are also included.

(1) Phenols having only one OH group and derivatives thereof Phenol, cresol, ethylphenol, t-butylphenol, methoxyphenol, salicyl alcohol, chlorophenol, aminophenol, aminocresol, amidazole, p- (2) -Aminoethyl) phenol, salicylic acid, o-salicylic anilide, naphthol, naphthol sulfonic acid, 7-amino-4-hydroxy-2-naphthalene disulfonic acid and the like.

(2) Phenols having two or more OH groups and derivatives thereof Catechol, resorcinol, hydroquinone, 4-methylpyrocatechol, 2-methylhydroquinone, pyrogallol, 1,2,5-benzenetriol, 1,3,3, 5-
Benzenetriol, 2-methylphloroglucinol,
2,4,6-trimethylphloroglucinol, 1,2,
3,5-benzenetetraol, benzenehexaol, tiron, aminoresorcinol, 2,4-dihydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde, dihydroxyacetophenone, 3,4-dihydroxybenzoic acid, gallic acid, 2, 3, 4 -Trihydroxybenzoic acid, 2,4-dihydroxy-6-methylbenzoic acid, naphthalenediol, naphthalenetriol,
Nitronaphthol, naphthalenetetraol, binaphthyldiol, 4,5-dihydroxy-2,7-naphthalenedisulfonic acid, 1,8-dihydroxy-3,6-naphthalenedisulfonic acid, 1,2,3-anthracenetriol and the like.

(3) Hydroxybenzophenones Dihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 2,6-dihydroxy-4-methoxybenzophenone, 2,2 ', 5,6'-tetrahydroxybenzophenone, 2,3 ', 4, 4', 6-pentahydroxy benzophenone etc.

(4) Hydroxybenzanilides o-hydroxybenzanilide etc. (5) Hydroxyaniles glyoxal bis (2-hydroxyanil) etc. (6) hydroxybiphenyls biphenyltetraol etc.

(7) Hydroxyquinones and derivatives thereof 2,3-Dihydroxy-1,4-naphthoquinone, 5-hydroxy-1,4-naphthoquinone, dihydroxyanthraquinone, 1,2-dihydroxy-3- (aminomethyl) anthraquinone -N, N '-2 acetic acid (Alizarin complex), trihydroxyanthraquinone, etc.

(8) Diphenyl or triphenylalkane derivative diphenylmethane-2,2'-diol, 4,4 ',
4 ′ ′-triphenylmethanetriol, 4,4′-dihydroxyfuchson, 4,4′-dihydroxy-3-methylfuxone, pyrocatechol violet [PV] and the like.

(9) Phenol Derivative of Alkylamine Ethylenediaminediorthohydroxyphenylacetic acid [E
DDHA], N, N-bis (2-hydroxybenzyl)
Ethylenediamine-N, N-2 acetic acid [HBED] etc

(10) Phenol derivatives of alkyl ethers 3,3'-ethylenedioxydiphenol and the like.

(11) Phenols having an azo group and derivatives thereof 4,4'-bis (3,4-dihydroxyphenylazo)
2,2'-stilbenedisulfonic acid diammonium [stilbazo], 2,8-dihydroxy-1- (8-hydroxy-3,6-disulfo-1-naphthylazo)-
3,6-Naphthalenedisulfonic acid, o, o'-dihydroxyazobenzene, 2-hydroxy-1- (2-hydroxy-5-methylphenylazo) -4-naphthalenesulfonic acid [carmagite], chlorohydroxyphenylazonaphthol, 1 '2-Dihydroxy-6-nitro-
1,2'-azonaphthalene-4-sulfonic acid [Eriochrome black T], 2-hydroxy-1- (2-hydroxy-4-sulfo-1-naphthylazo) -3,6-
Naphthalenedisulfonic acid, 5-chloro-2-hydroxy-3- (2,4-dihydroxyphenylazo) benzenesulfonic acid [lumogalion], 2-hydroxy-1
-(2-hydroxy-4-sulfo-1-naphthylazo)
-3-naphthalene acid [NN], 1,8-dihydroxy-
2- (4-sulfophenylazo) -3,6-naphthalenedisulfonic acid, 1,8-dihydroxy-2,7-bis (5-chloro-2-hydroxy-3-sulfophenylazo) -3,6-naphthalene Disulfonic acid, 1,8-dihydroxy-2,7-bis (2-sulfophenylazo)-
3,6-naphthalenedisulfonic acid, 2- [3- (2,
4, -Dimethylphenylaminocarboxy) -2-hydroxy-1-naphthylazo] -3-hydroxybenzenesulfonic acid, 2- [3- (2,4-dimethylphenylaminocarboxy) -2-hydroxy-1-naphthylazo] Such as phenol.

(12) Heterocyclic compounds having an OH group and derivatives thereof 8-quinolinol, 2-methyl-8-quinolinol, quinolinediol, 1- (2-pyridylazo) -2-naphthol, 2-amino-4 6,7,7-pteridine triol, 5,7,3′4′-tetrahydroxyflavone [luteolin], 3,3′-bis [N, N-bis (carboxymethyl) aminomethyl] fluorescein [calcein], 2, 3-hydroxypyridine and the like.

(13) Alicyclic compounds having an OH group and derivatives thereof, cyclopentanol, croconic acid, cyclohexanol, cyclohexanediol, dihydroxydiquinoyl, tropolone, 6-isopropyltropolone and the like.

The surface treatment composition of the present invention needs to contain at least one complexing agent selected from the above-mentioned Group A as a metal adhesion inhibitor. In selecting the complexing agent, it is generally judged and selected from the cleanliness level required for the substrate surface, the complexing agent cost, the chemical stability in the surface treatment composition to be added, etc. Although it can not be said that any complexing agent is the best, in terms of the metal adhesion preventing effect when the content is constant in the surface treatment composition, in particular ethylenediaminediorthohydroxyphenylacetic acid [EDDH
Phenol derivatives of alkylamines such as A] and the like and phenols having two or more OH groups such as catechol and tyrone, and derivatives thereof are excellent and are preferably used. In addition, phenol derivatives of alkylamines such as ethylenediaminediorthohydroxyphenylacetic acid [EDDHA] are superior in terms of chemical stability, and 8-quinolinol, catechol, tiron, etc. in terms of complexing agent production cost, respectively. It is excellent, and it is preferably used when emphasizing these. Furthermore, it is preferable that the complexing agent has a sulfonic acid group and a carboxyl group in addition to the OH group, since both the metal adhesion preventing effect and the chemical stability are excellent.

The complexing agent of Group B is a complexing agent having at least one atom selected from halogen, sulfur or carbon which is a donor atom in the molecular structure. In the present invention, the donor atom refers to an atom capable of supplying an electron necessary for a coordinate bond with a metal. Specific examples of such a complexing agent having a donor atom include, but are not limited to, those shown below. Further, salts of complexing agents specifically shown below are alkali metal salts, ammonium salts and the like.

(1) Complexing agent having halogen as donor atom Hydrofluoric acid or a salt thereof, hydrochloric acid or a salt thereof, hydrogen bromide or a salt thereof, hydrogen iodide or a salt thereof or the like.

[0026] (2) as a complexing agent coordinating groups having sulfur donor atoms, wherein HS ^-, S ^{2 _{chromatography, S 2 O 3 2-, RS}} -, R-
COS ^{chromatography,} has at least one group represented R-CSS ^{chromatography} or CS ₃ ^2-in, or selected RSH, thiol represented by R _'2 S Moshiku R ₂ C = S, sulfides or thiocarbonyl compound There is something to Here R
Represents an alkyl group, and R 'represents an alkyl group or an alkenyl group, and may be further linked to each other to form a ring containing a sulfur atom. Specifically, HS ^- group or S
Hydrogen sulfide or a salt thereof as having a ^2- group, or sulfides such as sodium sulfide and ammonium sulfide; S ₂ O ₃
Thiosulfuric acid or a salt thereof as having a ^2- group; RSH
Or, ethanethiol as having RS ^over group, a lower alkyl thiol or a salt thereof, such as 1-propanethiol; thioacetic acid as having an R-COS ^over group, Jichioshuu acid or a salt thereof; R-CSS ^over
Ethanedibis (dithio acid), dithioacetic acid or a salt thereof having a group; trithiocarbonic acid or a salt thereof as a group having a CS ₃ ^2- group, or thiocarbonates such as diethyl trithiocarbonate; sulfides represented by R ′ ₂ S As methyl sulfide, methylthioethane, diethyl sulfide, vinyl sulfide, benzothiophene and the like; propanethione as a thiocarbonyl compound represented by R ₂ C = S group, 2,
4-pentane dithione etc. are mentioned.

[0027] (3) as a complexing agent coordinating groups having carbon as a donor atom, those having an NC ^{chromatography,} RNC or RCC ^over. Specifically, hydrogen cyanide, cyanides such as ammonium cyanide, isocyanides such as ethyl isocyanide, allylene, metal acetylide and the like.

Among the above-mentioned B group, complexing agents having halogen as donor atom such as hydrofluoric acid and hydrochloric acid are particularly preferable.
It is excellent in both of the metal adhesion preventing effect and the cost, and is preferably used.

The amount of the complexing agent to be added as a metal adhesion inhibitor depends on the kind and amount of metal impurities in the liquid to be prevented from adhesion and the level of cleanliness required on the substrate surface, so it is generally determined. no but as the total amount of surface treatment composition, usually 10 ^-7 to 5 wt%, preferably 10
^{6 to} 0.1% by weight. If the amount is less than the above-mentioned addition amount, the metal adhesion preventing effect which is the object of the present invention is difficult to be expressed. On the other hand, if it is too large, not only the further effect can not be obtained, It is not preferable because there is a high risk of adhesion of certain complexing agents.

The liquid medium serving as the main component in the surface treatment composition of the present invention is not particularly limited, but usually, water, electrolytic ion water, acid, alkali, oxidizing agent, reducing agent, surfactant, etc. are dissolved. An aqueous solution or an organic solvent, or a mixture solution of these is used. In particular, in an alkaline aqueous solution or dilute hydrofluoric acid solution used for cleaning or etching of a semiconductor substrate, metal impurities in the solution are very likely to adhere to the surface of the substrate, and a complexing agent is added to these solutions according to the present invention. It is preferable to use it.

The alkaline aqueous solution used in the present invention is a generic term for an aqueous solution having a pH of more than 7. Although it does not specifically limit as an alkaline component of this aqueous solution, Ammonia is mentioned as a typical thing. Also, hydroxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide and calcium hydroxide, alkaline salts such as sodium hydrogencarbonate and ammonium hydrogencarbonate, or tetramethylammonium hydroxide (TMAM), trimethyl Also usable are quaternary ammonium salt hydroxides such as -2-hydroxyethyl ammonium hydroxide and choline. There is no problem even if two or more of these alkalis are added.
Usually, the total concentration is 0.01 in the total solution of the surface treatment composition
It is used so that it becomes -30 weight%. In addition, alkaline electrolytic ion water obtained by electrolysis of water is also preferably used. Further, an oxidizing agent such as hydrogen peroxide may be appropriately blended in such an alkaline aqueous solution. In the semiconductor wafer cleaning process, when bare silicon (without oxide film) is cleaned, the etching of the wafer and the surface roughness can be suppressed by the blending of the oxidizing agent. When hydrogen peroxide is added to the alkaline aqueous solution of the present invention, the concentration of hydrogen peroxide in the total solution of the surface treatment composition is usually 0.01 to 0.01.
It is used to be in a concentration range of 30% by weight.

The method of incorporating the complexing agent according to the present invention into the surface treatment composition is not particularly limited. Among components constituting the surface treatment composition (for example, ammonia water, hydrogen peroxide solution, water, etc.), one or more components are previously blended, and these components are mixed and used later. After mixing the said components, you may mix | blend and use this in this liquid mixture. Also, phenols, hydrochloric acid,
When adding acids such as hydrofluoric acid,
These may be added in the form of an acid, or may be added in the form of a salt such as an ammonium salt.

The surface treatment composition of the present invention is used for cleaning, etching, polishing, film formation, etc. of substrates such as semiconductors, metals, glasses, ceramics, plastics, magnetics, superconductors, etc. where contamination of metal impurities on the substrates is a problem. Used for surface treatment of In particular, the present invention is suitably used for cleaning and etching of a semiconductor substrate which requires a highly clean substrate surface. Especially in the cleaning of semiconductor substrates [ammonia + hydrogen peroxide +
When the present invention is applied to alkali cleaning with a cleaning solution consisting of water, the problem of metal impurity adhesion to the substrate, which is a problem of the cleaning method, is improved, thereby the metal contamination as well as particle and organic contamination by the cleaning. It is extremely preferable because a highly clean substrate surface is achieved.

Although the reason why the surface treatment composition of the present invention exerts a very good effect in preventing the adhesion of metal impurities is not yet clear, it is not clear that the two or more specific complexing agents to be added and the metal ions It is presumed that there is some mixing effect between them, and a stable water-soluble metal complex is formed very effectively.

When the surface treatment composition of the present invention is used as a washing solution to wash a substrate, a method is used in which the liquid is brought into direct contact with the substrate. As such a cleaning method, a dip type cleaning in which the cleaning tank is filled with the cleaning liquid to immerse the substrate, a spray type cleaning in which the liquid is sprayed onto the substrate for cleaning, a spin type cleaning in which the cleaning liquid is dropped on the substrate and rotated at high speed. Etc. In the present invention, among the above-mentioned cleaning methods, although an appropriate one is adopted according to the purpose, dip type cleaning is preferably used. With regard to the washing time, washing is carried out for a suitable time, preferably 10 seconds to 30 minutes, more preferably 30 seconds to 15
It is a minute. If the time is too short, the cleaning effect is not sufficient. If the time is too long, only the throughput will deteriorate, and the cleaning effect will not be improved. Cleaning may be performed at normal temperature, but may be performed with heating for the purpose of improving the cleaning effect. In the case of washing, it may be used in combination with a washing method by physical force. Examples of such physical force cleaning methods include ultrasonic cleaning and mechanical cleaning using a cleaning brush.

[0036]

EXAMPLES The present invention will next be described in detail by way of examples, which should not be construed as limiting the scope of the present invention. (Examples 1 to 5 and Comparative Examples 1 to 9) Ammonia water (30
%), Hydrogen peroxide solution (31% by weight) and water 0.2
The resulting mixed solution is used as an aqueous solvent of the main component by mixing in a volume ratio of 5: 1: 5, and this aqueous solvent contains two or more of the specific ones of the present invention described in Table 1 as metal antiadhesive agents. Predetermined amounts of various complexing agents were added to prepare a surface treatment composition of the present invention. For comparison, one obtained by adding one complexing agent out of the complexing agents used in the examples to the aqueous solvent, as disclosed in JP-A 3-21
Catechol, Tyron, which are complexing agents described in 9000,
Japanese Patent Application Laid-Open No. 5-27, to which catechol + citric acid is added
A compound to which EDTPO [ethylenediamine tetrakis (methyl phosphonic acid)] which is a complexing agent described in 5405 is added, a compound to which oxalic bis (salicylidene hydrazide) which is a complexing agent described in JP-A-6-163495, Also, one without addition of any complexing agent was also prepared.

In the surface treatment solution thus prepared, Al, F
After adding 10 ppb each of e as chloride, clean silicon wafer (p-type, CZ, plane direction (100))
Soak for 10 minutes. During immersion, the temperature of the surface treatment solution is
It heated and hold | maintained at 40-50 degreeC. A silicon wafer after immersion was subjected to overflow rinse with ultrapure water for 10 minutes and then dried by nitrogen blow to adhere to the wafer surface A
l and Fe were quantified. A deposited on a silicon wafer
l and Fe are 0.1 wt% hydrofluoric acid and 1 wt% hydrogen peroxide
The amount of the metal was measured by flameless atomic absorption spectrometry, and converted to the substrate surface concentration (atoms / cm ² ). The results are shown in Table 1.

[0038]

[Table 1]

[0039]

The surface treatment composition of the present invention contains metal impurities such as Al and Fe from the surface treatment composition to the surface of the substrate by containing two or more specific complexing agents as a metal adhesion inhibitor. Contamination can be prevented and a stable and extremely clean substrate surface can be achieved. In particular, when the present invention is applied to alkali cleaning of a semiconductor substrate represented by [ammonia + hydrogen peroxide + water] cleaning etc., the problem of metal impurity adhesion to the substrate, which is a problem of the cleaning method, is improved. Thus, the cleaning achieves a highly clean substrate surface free of metal contamination, as well as particle and organic contamination. For this reason, acid cleaning such as [hydrochloric acid + hydrogen peroxide + water] cleaning, which has conventionally been used after the cleaning, can be omitted, and the cost of cleaning and the cost of clean rooms such as exhaust equipment can be significantly reduced. This is a great advantage on the industrial production of semiconductor integrated circuits.

When manufacturing a device such as a semiconductor or liquid crystal,
In wet processes such as etching and cleaning, ultrapure water and ultrahigh purity chemicals having a metal impurity concentration of 0.1 ppb or less are used in order to prevent metal impurities from adhering to the substrate surface. Further, these chemicals need to be replaced frequently because metal impurities are mixed in during use. However, if the surface treatment composition of the present invention is used, adhesion can be prevented even if a large amount of metal impurities are present in the liquid, so there is no need to use ultra-high purity chemical solution, and the chemical solution is used. Since it is not necessary to replace frequently while being contaminated with metal impurities, it is possible to significantly reduce the cost of the chemical solution and its management. In addition, when a metal having a higher ionization tendency than the metal to be treated is present as an impurity in the cleaning solution during the etching or cleaning of the substrate where the metal is present on the surface, it adheres electrochemically to the substrate surface. If a substance is used, the metal impurity becomes a stable water-soluble metal complex, which can be prevented. Furthermore, if the composition of the present invention is applied to an abrasive slurry for polishing a substrate, adhesion of metal impurities, which are present in a large amount in the abrasive slurry and concentrated in the slurry as the substrate is polished, can be prevented. As described above, the ripple effect of the surface treatment agent of the present invention is great and industrially very useful.

Claims (11)

[Claim of claim] 1. A surface treatment composition containing a complexing agent as a metal antiadhesive agent in a liquid medium, wherein the complexing agent is (A)
An annular skeleton in the group) molecular structure, and OH groups and / or bonded to the carbon atom of the ring O ^- complexing agents with one or more groups, and (B group) donor molecular structure Surface treatment composition for a substrate comprising at least one complexing agent selected from each group of complexing agents having one or more atoms selected from halogen, sulfur or carbon . 2. The surface treatment composition according to claim 1, wherein the complexing agent of Group B does not contain a nitrogen atom which is a donor atom in its molecular structure. 3. The group B according to claim 1, wherein the complexing agent having a halogen which is a donor atom is hydrofluoric acid, hydrochloric acid, hydrogen bromide, hydrogen iodide or a salt thereof. The surface treatment composition according to any one of 2. 4. The complexing agent having sulfur as a donor atom in the group B is represented by the formula HS ⁻ , S ^{2 −} , S ₂ O ₃ ²⁻ , RS ⁻ ,
R-COS ^{chromatography,} has at least one coordinating group of the group represented R-CSS ^{chromatography} or CS ₃ ^2-in, or RSH,
R _'2 S or R ₂ C = thiols represented by S, the surface treatment composition according to any one of claims 1 or 2, characterized in that selected from sulfide or thiocarbonyl compound (with the proviso that said formula In which R represents an alkyl group,
R ′ represents an alkyl group or an alkenyl group, and may be further linked to each other to form a ring containing a sulfur atom). 5. The group B, complexing agents having a carbon atom as a donor atom, the formula NC ^{chromatography,} RNC or RC
At least one coordination surface treatment composition according to any one of claims 1 or 2, characterized in that it has a group of the groups represented by C ^over (wherein R represents an alkyl group) . 6. The complexing agent of group A comprises at least two OH and / or O ^- groups, and the complexing agent of group B comprises chlorine or fluorine atoms. The surface treatment composition according to any one of the above. 7. The addition amount of the metal deposition preventive agent 10 ^over 6 to 0.1
The surface treatment composition according to any one of claims 1 to 5, characterized in that it is% by weight. 8. The surface treatment composition according to claim 1, wherein the liquid medium is an alkaline aqueous solution. 9. The surface treatment composition according to claim 7, wherein the alkaline aqueous solution contains ammonia and hydrogen peroxide. 10. A method of treating a surface of a substrate comprising the step of treating the surface of a substrate using the surface treatment composition according to any one of claims 1 to 8. 11. A method of treating a surface of a substrate according to claim 9, wherein the substrate is a semiconductor substrate.