JP3449474B2 - Composition for surface treatment of semiconductor substrate and surface treatment method - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition for surface treatment of a semiconductor substrate used in a semiconductor manufacturing process and a surface treatment method.

[0002]

2. Description of the Related Art With the high integration of LSIs, the cleanliness control in the semiconductor manufacturing process tends to become more and more strict. In particular, in device miniaturization, control of particulate contamination on the substrate surface is so important that performance and yield are affected. For example, Tadahiro Omi, "Ultra Clean ULSI Technology" (Baifukan 1995) Nos. 157-1
According to page 58, particulate contamination causes pattern defects such as short circuits between wires and disconnections, and poor withstand voltage of the insulating film. The particle size that affects the yield is generally 1/5 to 1/10 of the design rule. Is described.

A cleaning process is introduced in the semiconductor process in order to avoid the deterioration of characteristics due to the contamination of fine particles as described above. Generally, RCA cleaning is widely known as a method for cleaning a silicon wafer. For RCA cleaning, June 1970, R.C.A.Review, Vol. 31, No. 2, pp. 187-206 (RCAR
view, P.M. 187-206, VOL. 31, N
O. 2, JUNE, 1970). According to this document, alkaline A is used for cleaning fine particle contamination.
A PM cleaning liquid (a mixed liquid of ammonia and hydrogen peroxide water) is used. The APM cleaning solution has a function of dissolving the vicinity of the surface while oxidizing the surface of the silicon substrate, desorbing the adhered fine particles from the surface, and preventing re-adhesion by an electrostatic repulsion action acting between the substrate surface and the fine particles. have.
By this action, fine particle contamination on the substrate surface is effectively removed.

However, when metal impurities are accumulated in the APM cleaning liquid, there arises a problem that the metal impurities adhere to the surface of the silicon substrate. The metal contamination on the surface of the silicon substrate is described, for example, in Kengo Shimanoe, "Cleaning and Analysis of Silicon Wafers" (Realize Co. 1998), pp. 7-9. According to this document, the neutral metal hydroxide dissolved in the alkaline solution is easily adsorbed on the silicon surface, and particularly in the APM cleaning solution, the metal impurities are taken into the oxide film formed on the silicon surface. This is a major problem of alkaline cleaning liquids containing an oxidizing agent such as APM cleaning liquid.

As a means for solving the problems of the alkaline cleaning liquid as described above, a method of adding additives such as a chelating agent and a surfactant to the cleaning liquid and using it for cleaning has been proposed.

The following methods have been disclosed as methods for adding a chelating agent to the cleaning liquid. JP-A-6-1167
Japanese Patent Publication No. 70 discloses a cleaning liquid in which a phosphonic acid-based chelating agent is added to a cleaning liquid composed of a basic aqueous hydrogen peroxide solution. According to this method, by adding a chelating agent having two or more phosphonic acid groups to a cleaning liquid composed of ammonia and hydrogen peroxide, adhesion of Fe metal contamination to the substrate surface is suppressed.

Japanese Unexamined Patent Publication (Kokai) No. 6-216098 discloses a method of adding a chelating agent to a mixed solution of alkali, hydrogen peroxide and water to wash a silicon wafer and further washing with hydrofluoric acid. There is. According to this method, the SC-2 cleaning solution (hydrochloric acid-peroxide) is used as a chelating agent by using a chelating agent in which 0.1 to 100 ppm of complexan or its carboxylic acid group ligand is replaced with another acid group. It is said that a metal contamination removing effect equivalent to that of the hydrogen oxide mixed solution) can be obtained, and then the chelating agent remaining on the substrate surface can be removed by washing with hydrofluoric acid.

Further, the following method has been disclosed as a method of adding a surfactant to the cleaning liquid. Japanese Patent Laid-Open No. 3-5308
No. 3 discloses that a specific anionic surfactant is added in an amount of 1 to 50 ppm to a cleaning solution or an etching solution containing an aqueous solution of ammonium fluoride, hydrogen peroxide solution, aqueous ammonia, etc., and metal impurities present in the chemical solution are semiconductors. A method for preventing metal contamination that suppresses deposition on the device surface is disclosed.

Further, the following method is disclosed as a method of adding both a chelating agent and a surfactant. Japanese Unexamined Patent Publication No. 5-259140 discloses a cleaning liquid in which a phosphonic acid chelating agent and a surfactant are added to a basic hydrogen peroxide aqueous solution. According to this method, contamination of Fe and Cu metal impurities present in the cleaning liquid on the substrate surface can be suppressed to a surface concentration of 1 × 10 ¹⁰ atoms / cm ² or less.

Japanese Unexamined Patent Publication (Kokai) No. 9-286999 discloses a silicon wafer cleaning composition comprising ammonia, a fluorosurfactant and a compound having a phosphonic acid group. According to this technique, when cleaning a silicon wafer, even if hydrogen peroxide is added to the cleaning liquid, the decomposition of hydrogen peroxide can be prevented, and the cleaning liquid has an excellent effect of removing fine particles and an effect of preventing metal contamination. Is supposed to be obtained.

Various methods of adding a surfactant to a cleaning liquid have been disclosed for the purpose of improving the cleaning performance for contamination of fine particles. Japanese Unexamined Patent Publication No. 5-251416 discloses a low surface tension aqueous ammonia composition comprising aqueous ammonia and a hydrogen fluoride-based surfactant. JP-A-5-33
Japanese Patent No. 5294 discloses a semiconductor substrate cleaning liquid obtained by adding a surfactant to a basic hydrogen peroxide aqueous solution.
Japanese Unexamined Patent Publication (Kokai) No. 6-13364 discloses a cleaning solution in which a specific nonionic surfactant is mixed with an acidic or alkaline hydrogen peroxide aqueous solution.

In JP-A-6-41770, a surfactant is added to a treatment liquid containing at least one of hydrofluoric acid, hydrochloric acid, nitric acid, aqueous hydrogen peroxide, acetic acid, ammonium fluoride and phosphoric acid. A method of treating a silicon wafer surface is disclosed. Japanese Patent Laid-Open No. 7-216392 discloses that
A cleaning agent and a cleaning method for a silicon wafer in which a specific surfactant is added to hydrofluoric acid are disclosed. Japanese Unexamined Patent Publication No. 8-69990 discloses a method for cleaning a semiconductor silicon wafer using a cleaning liquid composed of hydrofluoric acid, ozone and a surfactant.

Japanese Unexamined Patent Publication (Kokai) No. 8-195369 discloses a method of cleaning a silicon wafer substrate with a cleaning solution prepared by adding an anionic surfactant to a mixed solution of ammonia and hydrogen peroxide. Japanese Unexamined Patent Publication No. 9-223679 discloses a silicon wafer cleaning agent and a cleaning method which are composed of a specific hydrocarbon, an alkylene oxide compound and a nonionic surfactant. JP-A-11-11698
Japanese Patent Publication No. 4 discloses a cleaning composition for semiconductor substrates containing a compound having two or more phosphonic acid groups in the molecule, and a cleaning method using the same.

Japanese Unexamined Patent Publication (Kokai) No. 11-121418 discloses a cleaning composition for semiconductor substrates containing a nonionic compound having a specific molecular structure, and a cleaning method using the same. Japanese Patent Application Laid-Open No. 11-238725 discloses an etching composition in which a specific fluorine-based surfactant is added to buffered hydrofluoric acid composed of hydrogen fluoride, ammonium fluoride and water.

[0015]

However, JP-A-6-116770, JP-A-6-216098, JP-A-5-259140 and JP-A-9-286.
The methods disclosed in Japanese Patent Publication No. 999 aim to prevent metal contamination in an alkaline aqueous solution containing hydrogen peroxide, that is, an APM cleaning solution, and according to experiments conducted by the present inventors, Fe and Cu Although an excellent effect was obtained for such a metal that easily forms a chelate compound,
It was confirmed that the effect of preventing contamination was low for metals such as 1 which are difficult to form chelate compounds. further,
Since the oxide film is formed on the substrate surface by the hydrogen peroxide component contained in the treatment liquid, there is also a problem that a step of removing the oxide film with hydrofluoric acid or the like is required after the treatment.

Further, the method for preventing metal contamination disclosed in Japanese Patent Laid-Open No. 3-53083 has an excellent effect of preventing metal contamination in an acidic solution containing hydrofluoric acid or nitric acid, but in an alkaline solution. The problem was that the effect was significantly reduced, and the request could not be met.

It should be noted that JP-A-5-251416, JP-A-5-335294, JP-A-6-13364, JP-A-6-41770 and JP-A-7-216.
392, JP 8-69990, and JP 8
No. 195369, No. 9-223679, No. 11-116984, No. 11-2.
The cleaning method for removing fine particles disclosed in Japanese Patent No. 38725 has a high cleaning effect against fine particle contamination, but has a problem that the effect of preventing metal contamination is low.

The present invention has been made in view of the above-mentioned circumstances, and in the surface treatment of a semiconductor substrate using an alkaline solution, it prevents metal impurities from adhering to the substrate surface and prevents the formation of an oxide film. An object of the present invention is to provide a composition for surface treatment of a semiconductor substrate and a surface treatment method capable of effectively removing fine particle contamination on the substrate surface.

[0019]

The present inventors have noticed that metal contamination of a substrate surface in an alkaline cleaning liquid occurs on and in an oxide film formed on the substrate surface during cleaning, As a result of investigating the cleaning liquid, a cleaning liquid capable of removing fine particle contamination without forming an oxide film was completed.

That is, since the conventional alkaline cleaning liquid contains an oxidizing agent such as hydrogen peroxide or ozone, a hydrophilic oxide film is formed on the surface of the substrate due to the oxidizing action of the oxidizing agent. The effect of reducing the adhesive force of contamination and facilitating the removal thereof, and uniforming the etching of the surface of the substrate to prevent the surface from becoming rough can be obtained. However, as described above, the oxide film has a problem of inducing the adsorption of metal impurities, and a technique for preventing the adsorption of metal impurities in the alkaline cleaning liquid has been required. On the other hand, as a technique to prevent adsorption of metal impurities,
Although a method of adding a chelating agent to the above-mentioned cleaning solution has been proposed, the problem with these methods is that F
There is a problem in that the effect of preventing adsorption is obtained for metals that easily form chelate compounds such as e and Ni, but almost no effect is obtained for metals that are difficult to form chelate compounds such as Al and Zr. That is, the cleaning method of adding the above chelating agent is
Since it is added to the cleaning liquid, it is difficult to prevent the adsorption of Al, Zr, etc. on the oxide film formed on the substrate surface.

On the other hand, although a cleaning liquid containing no oxidizing agent such as hydrogen peroxide or ozone suppresses the formation of an oxide film, it has a problem that the surface of the substrate is unevenly etched, which causes a problem of surface roughness. It was

In view of the above-mentioned problems, the present inventors can prevent the adsorption of metal impurities and the occurrence of surface roughness to effectively remove fine particle contamination without forming an oxide film on the substrate surface. As a result of investigating the cleaning solution, it was found that an alkaline solution containing ammonia water, a surfactant having a specific molecular structure, and a chelating agent having a specific molecular structure is effective.

According to the present invention which solves the above-mentioned problems, the following compositions 1 to 12 are provided for a semiconductor substrate surface treatment composition and a surface treatment method. 1. (A) with ammonia, (b) the following general formula (1) R-O- (C m H 2m O) n -X ... (1) ( R in the formula hydrocarbon group, X is a hydrogen atom or a hydrocarbon
Group, m and n each represent a positive number).
Lioxyethylene glycol-based nonionic surfactant
And (c) a polyaminocarboxylic acid-based compound as a chelating agent
Compound or oxycarboxylic acid-based compound and (d) water, which is alkaline and has a semiconductor
Semi-conductor characterized by not forming an oxide film on the body substrate surface
Composition for surface treatment of body substrate. 2. (A) with ammonia, (b) the following general formula (2), (3) or (4) -COOY ... (2) -SO 3 Y ... (3) -OSO 3 Y ... (4) (Y in the formula Is hydrogen atom, metal atom or ammonium group
Anionic surface active agent having a hydrophilic group represented by
And (c) a polyaminocarboxylic acid compound as a chelating agent
Compound or oxycarboxylic acid-based compound and (d) water, which is alkaline and has a semiconductor
Semi-conductor characterized by not forming an oxide film on the body substrate surface
Composition for surface treatment of body substrate. 3. (A) with ammonia, (b) the following general formula (1) R-O- (C m H 2m O) n -X ... (1) ( R in the formula hydrocarbon group, X is a hydrogen atom or a hydrocarbon
Group, m and n each represent a positive number).
Lioxyethylene glycol-based nonionic surfactant
And (c) a polyaminocarboxylic acid-based compound as a chelating agent
Substance or an oxycarboxylic acid compound, and (d) water, which is alkaline and semiconductor
A semiconductor characterized by not forming an oxide film on the substrate surface
A composition for surface treatment of a substrate. 4. (A) with ammonia, (b) the following general formula (2), (3) or (4) -COOY ... (2) -SO 3 Y ... (3) -OSO 3 Y ... (4) (Y in the formula Is hydrogen atom, metal atom or ammonium group
Anionic surface active agent having a hydrophilic group represented by
And (c) a polyaminocarboxylic acid compound as a chelating agent
Substance or an oxycarboxylic acid compound, and (d) water, which is alkaline and semiconductor
A semiconductor characterized by not forming an oxide film on the substrate surface
A composition for surface treatment of a substrate. 5. The polyoxyethylene glycol-based nonionic field
The surface-active agent has an aromatic ring, 1 or
3. The composition for surface treatment of a semiconductor substrate of 3. 6. The anionic surfactant is dodecyl sulfate and
Characterized by being selected from alkylbenzene sulfonate
2. The composition for surface treatment of a semiconductor substrate according to 2 or 4. 7. The composition should be alkaline with a pH of 8-12
A composition for surface treatment of a semiconductor substrate according to any one of 1 to 6 above. 8. The composition has a chelating agent content of 10 to 1.0.
1 to 7 semiconductor groups characterized in that it is 00 mg / L
A composition for surface treatment of a plate. 9. The composition has (a) an ammonia content of 0.00
01-10 wt%, (b) surfactant content 0.00
01-0.1 wt%, (c) chelating agent content is 0.
001 to 1 wt% alkaline cleaning liquid
The composition for surface treatment of a semiconductor substrate according to any one of 1 to 7. 10. Instead of or with ammonia,
Selected from the group consisting of amines and ammonium salts
1 to 9 characterized by using one or more components
For treating the surface of a semiconductor substrate. 11. Use the composition of 11.1 to 10 for surface treatment of semiconductor substrate
A method for surface treatment of a semiconductor substrate, comprising:
Remove contaminants, prevent contaminants from sticking, surface flattening, or
Half characterized by performing surface modification treatment such as surface wetting
Surface treatment method for conductor substrate. 12. Use the composition for surface treatment of semiconductor substrate of 10.
A method for treating a surface of a semiconductor substrate, which comprises using the composition.
Application of ultrasonic waves during the surface treatment of the semiconductor substrate.
A surface treatment method for a semiconductor substrate, comprising:

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

According to the method for surface-treating a semiconductor substrate using the above-mentioned composition for surface treatment, since the composition does not contain an oxidizing agent such as hydrogen peroxide, the surface treatment of the semiconductor substrate is not performed. No oxide film is formed on the surface, adhesion of metal impurities to the oxide film is prevented, and metal contamination on the substrate surface is prevented. Further, in addition to the substrate etching action of the composition and the electrostatic repulsion action caused by alkalinity, by applying ultrasonic waves to the composition, fine particle contamination on the substrate surface is effectively removed.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is characterized by cleaning fine particle contamination adhering to a semiconductor substrate. Therefore, the surface treatment method of the present invention is not particularly limited as long as it is a semiconductor substrate. Specifically, a silicon substrate can be used. Silicon substrates have high requirements for fine particle contamination and metal contamination, and the effects of the present invention are remarkably exhibited. In addition to the silicon substrate, a silicon oxide substrate, an SOI substrate, a substrate made of a III-V group semiconductor material, or the like can be used.

As the surface treatment composition of the present invention,
As described above, an alkaline solution containing ammonia, a nonionic or anionic surfactant, a chelating agent, and the balance being water is used.

The surface-treating composition according to the present invention may be alkaline, but preferably has a pH of 8 or higher, more preferably pH 9 or higher to prevent adhesion of metal contamination to the surface of the substrate and fine particles. Contamination can be removed more effectively. Further, by setting the pH to 13 or less, more preferably 12 or less, it is possible to suppress the roughness of the substrate surface caused by the etching of the substrate.

As the alkali component contained in the surface treatment composition of the present invention, for example, those containing ammonia, amines, ammonium salts and the like are used. Whichever of these is selected, the etching action due to being alkaline and the electrostatic repulsion action between the fine particles and the substrate can be obtained, and the fine particle contamination can be removed. However, more advantages can be obtained by selecting a particular type of the above. For example, it is preferable to contain one or more components selected from the group consisting of ammonia, tetramethylammonium hydroxide (TMAH), and trimethyl (2-hydroxy) ethylammonium hydroxide. If a cleaning liquid containing such a component is used, it is possible to more effectively remove fine particle contamination. In addition, there is an advantage that the rinsing step after cleaning can be simplified. Of these, ammonia is particularly preferable. When ammonia is used, the amount of the cleaning liquid remaining can be particularly reduced, and the rinsing step after cleaning can be significantly simplified. Further, it is easy to control the concentration of the cleaning liquid, and it is possible to reduce variations in processing due to changes in the composition of the cleaning liquid.

As the surfactant contained in the surface treatment composition of the present invention, the polyoxyethylene glycol nonionic surfactant represented by the general formula (1) is used. Specific examples thereof include nonionic surfactants such as octylphenyl polyoxyethylene ether having an aromatic ring. Further, instead of the nonionic surfactant, an anionic surfactant having a hydrophilic group represented by the general formula (2), (3) or (4) may be used. Specific examples thereof include dodecyl sulfate salt and alkylbenzene sulfonate. By using the above-mentioned surfactant, not only the effect of preventing metal contamination can be enhanced, but also the redeposition of particulate contamination once removed can be effectively prevented.

The content of the surfactant is preferably 1 to 1,000 mg / L, more preferably 10 to 500 mg / L with respect to the surface treatment composition. If this concentration is too low, sufficient metal contamination prevention effect cannot be obtained, and conversely, if it is too high, organic substances remain on the surface of the substrate and cause deterioration of the performance of semiconductor devices, and waste liquid treatment is expensive. To do.

As the chelating agent contained in the surface treating composition of the present invention, a polyaminocarboxylic acid compound or an oxycarboxylic acid compound is used.
Specifically, ethylenediaminetetraacetic acid (EDTA), trans-1,2-cyclohexanediaminetetraacetic acid (Cy
Polyaminocarboxylic acid compounds such as DTA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), N- (2-hydroxyethyl) ethylenediamine-N, N ', N'-triacetic acid (EDTA-OH), glucone Examples thereof include oxycarboxylic acid compounds such as acids, tartaric acid, citric acid, and salts thereof. When a salt is used, a salt that does not adversely affect the characteristics of the semiconductor device is preferable, and a salt containing no metal such as an ammonium salt is particularly preferable. If the above chelating agent is used,
Not only can the effect of preventing metal contamination be enhanced, but the redeposition of metal impurities once removed can be effectively prevented.

The content of the chelating agent is preferably 1 to 10,000 mg / L, more preferably 10 to 1,000 mg / L with respect to the surface treatment composition. If this concentration is too low, a sufficient chelating effect cannot be obtained, while if it is too high, organic substances remain on the surface of the substrate and cause deterioration of the performance of the semiconductor device, or waste liquid treatment is expensive.

The surface treating composition of the present invention preferably contains no oxidizing agent. In particular, when hydrogen peroxide, which is widely used for substrate cleaning, is included, it forms an oxide film on the substrate surface to induce the adhesion of metal impurities, and the decomposition of hydrogen peroxide causes foaming to limit the range of use of the cleaning liquid. Therefore, it is preferable to avoid the combined use.

In carrying out the surface treatment in the present invention, it is preferable to apply ultrasonic waves. By doing so, the cleaning effect can be further enhanced. At this time, the frequency of ultrasonic waves is preferably 800 kHz or higher. 8
If it is less than 00 kHz, the substrate may be damaged, and the cleaning action by ultrasonic waves may not be sufficiently obtained.

[0044]

EXAMPLE (Example 1) In this example, a model experiment was conducted using a silicon wafer on which polystyrene latex particles were attached. As a cleaning liquid, a mixed liquid of ammonia water, a chelating agent, and a surfactant was used, and cleaning was performed under various compositions and temperature conditions, and the cleaning effect and the metal contamination preventing effect were evaluated.

First, a plurality of 6-inch silicon wafers were prepared, and the wafers were immersed in a dispersion liquid of polystyrene latex. After drying the wafer surface, ammonia water (0.018 wt%) was used as a cleaning liquid and E was used as a chelating agent.
DTA (0.1 wt%) and polyoxyethylene octyl phenyl ether as a surfactant (100 mg /
A mixed solution (pH 9.5) containing L) was used and immersed in this for 5 minutes for cleaning. The temperature of the cleaning liquid was 25 ° C.
Fe, Al, and Cu as metal impurities in the cleaning liquid are each 1
00 μg / L was added. Ultrasonic waves were applied at 1.5 MHz during cleaning. Then, it was thoroughly rinsed with pure water.
With respect to the above wafers, the polystyrene latex particle removal rate before and after cleaning, the amount of adhered metal contamination on the wafer surface, and the wafer surface morphology were evaluated. The evaluation method is shown below.

(Latex Particle Removal Rate) The amount of polystyrene latex particles remaining on the surface of the wafer after cleaning was measured using a particle counter. Based on this result, the number of polystyrene latex particles before washing is 100
The removal rate when calculated as% was calculated. The polystyrene latex particle removal rate after washing is shown in Table 1.

(Amount of Adhered Metal Contamination) An appropriate amount of hydrofluoric acid-hydrogen peroxide mixture solution (HF 1 wt%, hydrogen peroxide 3 wt%) was dropped on the cleaned wafer surface, and spread over the entire wafer surface. Was collected in a container. Each component of Fe, Al, and Cu in the solution was quantified with a graphite furnace atomic absorption spectrometer. The measurement value of graphite furnace atomic absorption spectrometry for each wafer was calculated as the contamination concentration on the 6-inch wafer. The results are shown in Table 1.

(Wafer Surface Morphology) The wettability of the wafer surface after cleaning is observed, and if a uniform hydrophobic surface (contact angle to water is 90 ° or more) appears, a bare silicon surface or a uniform hydrophilic surface is obtained. If it appears, it is taken as the oxide film surface. The results are shown in Table 1.

(Example 2) As a cleaning liquid, aqueous ammonia (0.17 wt%), EDTA (0.1 wt%) and polyoxyethylene octyl phenyl ether (100 mg)
Cleaning test and evaluation were performed in the same manner as in Example 1 except that the mixed solution (pH 9.5) was used. The results are shown in Table 1.

(Example 3) The temperature of the cleaning liquid was set to 35 ° C,
As cleaning liquid, ammonia water (0.075 wt%) and E
Mixture of DTA (0.1 wt%) and polyoxyethylene octyl phenyl ether (100 mg / L) (pH
A cleaning experiment and evaluation were performed in the same manner as in Example 1 except that 9.5) was used. The results are shown in Table 1.

(Example 4) The temperature of the cleaning liquid was set to 45 ° C,
Ammonia water (0.36 wt%) and ED as cleaning liquid
Mixture of TA (0.1 wt%) and polyoxyethylene octyl phenyl ether (100 mg / L) (pH 1
A washing experiment and evaluation were performed in the same manner as in Example 1 except that 0.5) was used. The results are shown in Table 1.

(Comparative Example 1) As a cleaning liquid, an APM cleaning liquid (1 wt% ammonia, 5 wt% hydrogen peroxide, 60 ° C.)
A cleaning experiment and evaluation were performed in the same manner as in Example 1 except that the above was used. The results are shown in Table 1.

[0053]

[Table 1]

In each of Examples 1 to 4, by applying ultrasonic waves at the time of cleaning, fine particle removability equivalent to that of the APM cleaning liquid was obtained. Moreover, in Examples 1 to 3, all the amounts of adhered metal contamination were D.I. L. Below, only Al was detected in Example 4. Furthermore, in Examples 1 to 4,
In both cases, the surface morphology was maintained on the bare silicon surface. On the other hand, in Comparative Example 1, although the fine particle removal rate is high,
The effect of preventing metal contamination was low, and an oxide film was formed on the surface of the wafer after cleaning.

Example 5 CyDTA was used as a chelating agent.
A cleaning experiment and evaluation were performed in the same manner as in Example 1 except that (0.1 wt%) was used. Table 2 shows the measurement results of the amount of adhered metal contamination and the surface morphology.

Example 6 A washing experiment and evaluation were conducted in the same manner as in Example 1 except that gluconic acid (0.1 wt%) was used as the chelating agent. Table 2 shows the measurement results of the amount of adhered metal contamination and the surface morphology.

(Comparative Example 2) A cleaning experiment was conducted in the same manner as in Example 1 except that a mixed solution of aqueous ammonia (0.0002 wt%) and polyoxyethylene octylphenyl ether (100 mg / L) was used as the cleaning solution. And evaluated. Table 2 shows the measurement results of the amount of adhered metal contamination and the surface morphology.

(Comparative Example 3) As a cleaning liquid, an APM cleaning liquid (ammonia 1 wt%, hydrogen peroxide 5 wt%, 60 ° C.)
A cleaning experiment and evaluation were performed in the same manner as in Example 1 except that a mixed solution of EDTA (0.1 wt%) and polyoxyethylene octylphenyl ether (100 mg / L) was used. Table 2 shows the measurement results of the amount of adhered metal contamination and the surface morphology.

[0059]

[Table 2]

In the fifth embodiment, the amount of deposited metal is D.
L. It was below. In Example 6, only Cu was detected. On the other hand, in Comparative Examples 2 and 3, the effect of preventing metal contamination was insufficient, and particularly in Comparative Example 3 in which the cleaning liquid contained hydrogen peroxide, an oxide film was formed on the surface after cleaning.

[0061]

According to the present invention, metal impurities in an alkaline solution are prevented from adhering to the surface of a semiconductor substrate, and
It is possible to prevent the formation of an oxide film and effectively remove the contamination of fine particles adhering to the surface of the semiconductor substrate.

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Claims (12)

(57) [Claims] 1. (a) Ammonia, and (b) the following general formula (1) R—O— (C _m H _2m O) _n —X (1) (wherein R is a hydrocarbon group and X is A hydrogen atom or a hydrocarbon group, m and n each represent a positive number), and (c) a polyaminocarboxylic acid compound or an oxycarboxylic acid as a chelating agent. a system compound, Ri Do from (d) and water, with an alkaline, an oxide film on a semiconductor substrate surface
A composition for surface treatment of a semiconductor substrate, which is not formed . 2. A (a) ammonia, (b) the following general formula (2), (3) or (4) -COOY ... (2) -SO 3 Y ... (3) -OSO 3 Y ... (4) An anionic surfactant having a hydrophilic group represented by the formula (Y represents a hydrogen atom, a metal atom or an ammonium group), and (c) a polyaminocarboxylic acid compound or an oxycarboxylic acid compound as a chelating agent . If, Ri Do from (d) and water, with an alkaline, an oxide film on a semiconductor substrate surface
A composition for surface treatment of a semiconductor substrate, which is not formed . 3. (a) ammonia, and (b) the following general formula (1) R—O— (C _m H _2m O) _n —X (1) (wherein R is a hydrocarbon group and X is A hydrogen atom or a hydrocarbon group, m and n each represent a positive number), and (c) a polyaminocarboxylic acid compound as a chelating agent.
And objects or oxycarboxylic acid compound, and a (d) water, with an alkaline, an oxide film on a semiconductor substrate surface
A composition for surface treatment of a semiconductor substrate, which is not formed . 4. A (a) ammonia, (b) the following general formula (2), (3) or (4) -COOY ... (2) -SO 3 Y ... (3) -OSO 3 Y ... (4) (Y in the formula represents a hydrogen atom, a metal atom or an ammonium group) and an anionic surfactant having a hydrophilic group, and (c) a polyaminocarboxylic acid-based compound as a chelating agent.
And objects or oxycarboxylic acid compound, and a (d) water, with an alkaline, an oxide film on a semiconductor substrate surface
A composition for surface treatment of a semiconductor substrate, which is not formed . 5. The polyoxyethylene glycol-based non-polyamide
Ionic surfactants are characterized by having an aromatic ring
A surface treatment set for a semiconductor substrate according to claim 1 or 3,
A product. 6. The anionic surfactant is dodecyl sulfate.
Selected from sodium salt and alkylbenzene sulfonate
The semiconductor substrate according to claim 2 or 4, characterized in that
The composition for surface treatment of. 7. The composition is alkaline having a pH of 8-12.
In any one of Claims 1-6 characterized by the following.
A composition for surface treatment of a semiconductor substrate as described above. 8. The chelating agent content of the composition is 1
It is 0-1,000 mg / L, It is characterized by the above-mentioned.
For surface treatment of the semiconductor substrate according to any one of 1 to 7
Composition. 9. The composition comprises (a) ammonia content
Is 0.0001 to 10% by weight, (b) surfactant content
Is 0.0001 to 0.1% by weight, and (c) contains a chelating agent.
It is an alkaline cleaning liquid with a percentage of 0.001 to 1% by weight.
The method according to any one of claims 1 to 7, characterized in that
A composition for surface treatment of a semiconductor substrate. 10. Ammoni instead of ammonia
Together with a group consisting of amines and ammonium salts
Characterized by using one or more components selected from
The semiconductor substrate according to any one of claims 1 to 9,
A composition for surface treatment. 11. The method according to any one of claims 1 to 10.
Of a semiconductor substrate using the composition for surface treatment of a semiconductor substrate of
A surface treatment method, comprising removing contaminants on the substrate surface,
For preventing adhesion of contaminants, surface flattening, surface wetting, etc.
Surface of semiconductor substrate characterized by performing surface modification treatment
Processing method. 12. The method according to any one of claims 1 to 10.
Of a semiconductor substrate using the composition for surface treatment of a semiconductor substrate of
A method for surface treatment, comprising using the composition to form a semiconductor substrate
It is characterized by applying ultrasonic waves when performing the surface treatment of
Surface treatment method for semiconductor substrate.