JP3332323B2 - Cleaning method and cleaning device for electronic component members - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cleaning electronic parts such as a semiconductor substrate, a glass substrate, an electronic part, and parts for manufacturing these components.

[0002]

2. Description of the Related Art In the process of manufacturing electronic parts such as LSIs, it is sometimes required to make the surface extremely clean. For example, in LSI, a silicon oxide insulating film is formed on a silicon wafer, a resist layer is provided in a predetermined pattern on the silicon film, and the insulating film in a portion where the resist layer is not provided is removed by etching or the like to remove metal silicon. After exposing the surface and cleaning the surface, a step (lithography process) of introducing a p-type or n-type element according to the purpose and embedding a metal wiring such as aluminum is repeated to manufacture an element. When introducing an n-type element or embedding metal wiring, if foreign matter such as fine particles, metal, organic matter, natural oxide film, etc. adhere to the metal silicon surface, the metal silicon and the metal wiring may The characteristics of the element may be poor due to poor contact or increased contact resistance. For this reason, in the LSI manufacturing process, the step of cleaning the surface of the silicon wafer is a very important step for obtaining a high-performance device, and it is necessary to remove impurities adhering to the silicon wafer as much as possible.

Conventionally, the cleaning of a silicon wafer is a combination of cleaning with a mixed solution of sulfuric acid and hydrogen peroxide, a mixed solution of hydrochloric acid and hydrogen peroxide, a hydrofluoric acid solution, an ammonium fluoride solution, and the like, and cleaning with ultrapure water. This removes organic substances, fine particles, metals, natural oxide films and the like adhering to the silicon wafer surface without deteriorating the flatness of the silicon wafer surface at the atomic level.

The following (1) to (13) are specific examples of a conventional silicon wafer cleaning process. (1) Sulfuric acid / hydrogen peroxide solution washing step; a mixed solution of sulfuric acid: hydrogen peroxide solution = 4: 1 (volume ratio) at 130 ° C.
Wash for 0 minutes. (2) Ultrapure water washing step; washing with ultrapure water for 10 minutes. (3) Hydrofluoric acid washing step; washing with 0.5% hydrofluoric acid for 1 minute. (4) Ultrapure water washing step; washing with ultrapure water for 10 minutes. (5) Ammonia / hydrogen peroxide water washing step; washing with a mixed solution of ammonia water / hydrogen peroxide / ultra pure water = 0.05: 1: 5 (volume ratio) at 80 ° C. for 10 minutes. (6) Ultrapure water washing step; washing with ultrapure water for 10 minutes. (7) Hydrofluoric acid washing step: washing with 0.5% hydrofluoric acid for 1 minute. (8) Ultrapure water washing step: washing with ultrapure water for 10 minutes. (9) Hydrochloric acid / hydrogen peroxide water washing step: a mixed solution of hydrochloric acid: hydrogen peroxide water: ultra pure water = 1: 1: 6 (volume ratio)
Wash at 80 ° C for 10 minutes. (10) Ultrapure water washing step; washing with ultrapure water for 10 minutes. (11) Hydrofluoric acid washing step; washing with 0.5% hydrofluoric acid for 1 minute. (12) Ultrapure water washing step; washing with ultrapure water for 10 minutes. (13) Spin drying or IPA vapor drying

The step (1) is mainly for removing organic substances adhering to the surface of the silicon wafer,
The step (5) is mainly for removing fine particles adhering to the silicon wafer surface, and the step (9) is mainly for removing metal impurities on the silicon wafer surface. Steps (3), (7) and (11) are performed to remove the natural oxide film on the surface of the silicon wafer. In addition, the cleaning liquid in each of the above steps often has a contaminant removing ability other than the above-mentioned main purpose. For example, the mixed solution of sulfuric acid and hydrogen peroxide used in the step (1) is not only organic but also organic substances. Since it also has a strong action of removing metal impurities, in addition to the above-described method of removing different impurities by each cleaning solution, there is also a method of removing a plurality of impurities with one type of cleaning solution.

In the silicon wafer cleaning step, a method of bringing a cleaning liquid or ultrapure water into contact with the silicon wafer surface is generally called a batch cleaning method in which a plurality of silicon wafers are immersed in a cleaning tank containing the cleaning liquid or ultrapure water. Although the method is adopted, in order to prevent contamination of the cleaning liquid, a method of cleaning while circulating and filtering the cleaning liquid, and a cleaning method using ultrapure water after treatment with the cleaning liquid, supplying ultrapure water from the bottom of the cleaning tank. An overflow cleaning method that overflows from the top of the cleaning tank, a quick dump cleaning method that stores ultrapure water in the cleaning tank until the entire surface of the wafer is immersed in ultrapure water, and then discharges the ultrapure water from the bottom of the cleaning tank at a stretch Etc. have also been adopted. In recent years, in addition to the batch cleaning method, a method of spraying a cleaning liquid or ultrapure water on a wafer surface in a shower shape or cleaning the wafer by rotating the wafer at a high speed and spraying a cleaning liquid or ultrapure water on the center thereof. A so-called single wafer cleaning method such as a method is also employed.

The cleaning with ultrapure water is performed to rinse (rinse) a cleaning liquid or the like remaining on the wafer surface. Therefore, the ultrapure water used for rinsing is high purity ultrapure water from which fine particles, colloidal substances, organic substances, metal ions, anions, dissolved oxygen and the like have been removed to an extremely low level. This ultrapure water is also used as a solvent for the cleaning liquid.

[0008]

In recent years, the degree of integration of LSI has been dramatically improved. In the early days, the number of lithography processes in the LSI manufacturing process was about several times.
From 30 times to 30 times, and the number of times of cleaning of the wafer also increases with the increase in the lithography process. For this reason, the cost of the cleaning liquid and ultrapure water used for cleaning the wafer, the cost of processing the used cleaning liquid and ultrapure water, and the cleaning liquid gas generated in the clean room due to the high temperature cleaning process are discharged from the clean room. The air cost, etc. of the products has increased, which has led to an increase in product costs. The lowering of the concentration and use amount of the cleaning solution, the lowering of the cleaning process, the reduction in the number of processes per cleaning process, and the super- A challenge is to reduce the amount of pure water used.

[0009] In the above-described cleaning process of the LSI or the like, the organic substances adhering to the surface of the silicon wafer deteriorate the performance of the LSI and significantly reduce the yield of the LSI. If the organic substance is in the form of a film and metal impurities or fine particles adhere to the inside of the film, or if a natural oxide film is formed, cleaning with hydrofluoric acid, cleaning with hydrochloric acid hydrogen peroxide, aqueous ammonia hydrogen peroxide, etc. Even if cleaning is performed, there is a problem that metal impurities, fine particles, natural oxide films and the like cannot be sufficiently removed.

[0010] For this reason, in the conventional washing process, the organic matter is usually removed first. Conventionally, for removing organic substances, a method of washing with a sulfuric acid hydrogen peroxide solution as in the above-described example has been mainly employed. However, since a concentrated sulfuric acid solution of tens of percent is used, chemicals (sulfuric acid and sulfuric acid) are used. (Hydrogen peroxide solution) The amount of use increases, and a large amount of ultrapure water is required for rinsing after washing. This not only increases the cost of chemicals used to prepare the sulfuric acid hydrogen peroxide solution, but also causes large-scale wastewater and wastewater to be used for the treatment of used sulfuric acid hydrogen peroxide solution and the disposal of ultrapure water used for rinsing. A processing facility is required, and the installation cost and operating cost of such a processing facility become enormous, which raises the problem of raising the manufacturing cost of products. In addition, since the sulfuric acid / hydrogen peroxide solution cleaning is performed at a high temperature, not only a heat source is required, but also a chemical gas is generated, so it is necessary to discharge the chemical gas from the clean room. There is a problem that the cost for the operation is high.

On the other hand, recently, a method of removing organic substances by washing with ultrapure water in which ozone gas is dissolved has begun to be put into practical use. For example, ultrapure water in which 2 to 10 ppm of ozone gas is dissolved is used for about 10 minutes at room temperature. Cleaning methods have also been proposed. However, in the method of cleaning at room temperature with ultrapure water in which ozone gas is dissolved, it is difficult to sufficiently remove organic substances when the amount of organic substances attached is large or when organic substances are hardly decomposable. In addition, there is a possibility that organic matter remains even after long-time cleaning.

As a result of various studies to solve the above problems, the present inventors have found that not only washing with ultrapure water in which ozone gas is dissolved but also washing with an alkaline cleaning solution in which ozone gas is dissolved in ultrapure water. As a result, it has been found that organic substances can be easily and reliably removed, and the present invention has been completed based on such findings.

The present invention can contribute to reducing the amount of chemicals required for cleaning and ultrapure water, and can reliably and easily remove organic substances on the surface of electronic component members even at a low temperature. It is an object of the present invention to provide a kind of cleaning method and a cleaning device.

[0014]

According to the present invention, there is provided (1) an electronic component member having a dissolved gas concentration of less than 10 ppm.
Ozone gas is dissolved in ultrapure water which has been degassed , and is cleaned with an alkaline cleaning solution having a positive oxidation-reduction potential. (1) The method for cleaning electronic component members according to (1), wherein ozone gas of 0.05 ppm or more is dissolved, (3) The pH of the alkaline cleaning liquid is more than 7 and 11 or less ( (1) The method for cleaning electronic component members according to (2),
(4) The method of cleaning electronic component members according to any one of (1) to (3) , wherein the cleaning is performed while irradiating ultrasonic waves. (5) The temperature of the alkaline cleaning liquid is set to 20 ° C to 6 ° C.
It is characterized by washing at a temperature of 0 ° C. (1) to
(4) The method for cleaning electronic component members according to any of (4) ,
(6) The method for cleaning electronic component members according to any one of (1) to (5) , wherein the ozone gas is dissolved in ultrapure water via a gas permeable membrane, (7) an ultrapure water apparatus If, soluble
Gas dissolving means for dissolving ozone gas in ultrapure water degassed to a concentration of less than 10 ppm , pH adjusting means for adjusting the solution to alkaline, ultrapure water A cleaning unit for cleaning electronic parts and components with an alkaline cleaning liquid having a positive oxidation-reduction potential in which ozone gas is dissolved in a cleaning device for electronic parts and components, (8) dissolving in an alkaline cleaning liquid Dissolved ozone concentration detecting means and pH detecting means for detecting the dissolved ozone concentration and the pH of the solution, respectively, and controlling the dissolved ozone concentration and the pH in the alkaline cleaning liquid based on the detection results of the dissolved ozone concentration and the pH, respectively. Characterized by having dissolved ozone concentration control means and pH control means
(7) The apparatus for cleaning electronic component members according to (7) , (9) The electronic component members according to (7) or (8) , further including an ultrasonic irradiation unit for irradiating the cleaning unit with ultrasonic waves. The gist of the cleaning device is as follows.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method of the present invention, various components and materials used in the electronic component manufacturing field and the like are listed as electronic component members (objects to be cleaned) to be cleaned. Substrate materials such as semiconductor substrates such as III-V semiconductor wafers, glass substrates for liquid crystal, etc., finished products and semi-finished products such as electronic components such as memory devices, CPUs and sensor devices, quartz reaction tubes, cleaning tanks, substrate carriers And the like for an electronic component manufacturing apparatus.

In the present invention, ultrapure water is industrial water,
Raw water such as tap water, well water, river water, lake water, etc. is treated with a pretreatment device such as coagulation sedimentation, filtration, coagulation filtration, activated carbon treatment, etc. to remove coarse suspended substances, organic matter, etc. in the raw water. Then, by processing in a primary pure water producing apparatus mainly comprising a desalination apparatus such as an ion exchange apparatus and a reverse osmosis membrane apparatus,
Removal of most of impurities such as fine particles, colloidal substances, organic substances, metal ions and anions, and treatment of this primary pure water with an ultraviolet irradiation device, mixed-bed polisher, ultrafiltration membrane and reverse osmosis membrane It refers to high-purity pure water in which impurities such as fine particles, colloidal substances, organic substances, metal ions, and anions have been removed as much as possible by circulating in a secondary pure water production system. Is, for example, an electric resistivity of 17.0 MΩ · cm or more, a total organic carbon of 100 μgC / liter or less, and a number of fine particles (particle size 0.07
μm or less), the number of viable bacteria is 50 or less, silica is 10 μg SiO ₂ /
Liter or less, sodium 0.1 μg Na / liter or less. In the apparatus of the present invention, the ultrapure water production apparatus refers to a combination of the above-described pretreatment apparatus, primary pure water production apparatus, and secondary pure water production apparatus. In addition, a case where a deaerator such as a vacuum deaerator or a membrane deaerator using a gas permeable membrane is added at the subsequent stage of the primary pure water production apparatus is included, and as raw water, industrial water, clean water, A mixture of well water, river water, lake water, etc. mixed with various types of recovered water collected in the factory may be used.

FIG. 1 shows an example of an apparatus for cleaning electronic parts and members of the present invention. In the figure, reference numeral 1 denotes an ultrapure water production apparatus, 2 denotes a gas dissolving tank, 3 denotes a pH adjusting apparatus, and 4 denotes a cleaning tank. The apparatus further includes a degassing apparatus 5 for removing gas dissolved in the ultrapure water produced by the ultrapure water producing apparatus 1 and a cleaning target to be cleaned in the cleaning tank 4, if necessary. An ultrasonic irradiation device 7 for irradiating the object 6 with ultrasonic waves is provided.

The ultrapure water producing apparatus 1 includes a pretreatment device for treating raw water with a coagulating sedimentation device, a sand filtration device, and an activated carbon filtration device, and a reverse osmosis membrane device, a two-bed three-column ion exchange device. , A mixed-bed ion exchange device, a primary-pure water production device that obtains primary purified water by processing with a precision filter, and a primary-purified water that is subjected to ultraviolet irradiation, a mixed-bed polisher, and an ultrafiltration membrane treatment. A secondary pure water producing apparatus for removing fine particles, colloidal substances, organic substances, metal ions, anions and the like remaining in the apparatus is provided, and a degassing apparatus is further provided if necessary (neither is shown). .

The ultrapure water produced by the ultrapure water production apparatus 1 preferably has, for example, the water qualities shown in Table 1 below. It is said that no contaminants therein adhere to the wafer surface.

[0020]

[Table 1]

Ozone gas is dissolved in the ultrapure water produced by the ultrapure water producing apparatus 1 in the gas dissolving tank 2.
By dissolving ozone gas in ultrapure water, a cleaning liquid having a positive redox potential suitable for removing organic substances on the surface of a wafer or the like can be obtained. Is 0.05 ppm or more, especially 1 pp
It is preferable that the ozone gas is dissolved in the gas dissolving tank 2 so that the concentration becomes 10 to 10 ppm. Gas dissolving tank 2
The ultrapure water supplied to the plant is usually degassed during production, so the dissolved gas concentration in the ultrapure water is very low, but nitrogen and carbon dioxide react with ozone and ionize. Before the ultrapure water is introduced into the gas dissolving tank 2, dissolved nitrogen or dissolved nitrogen remaining in the ultrapure water is introduced before the ultrapure water is introduced into the gas dissolving tank 2. Further removal of carbon dioxide .

In the degassing apparatus 5, the gas dissolving tank 2
Total dissolved gas concentration of the ultrapure water is less than 10ppm supplied to, preferably degassed so that 2ppm or less
You. If the dissolved gas concentration is 10 ppm or more, bubbles are generated during cleaning, the bubbles adhere to the object to be cleaned, and the cleaning effect on the portion to which the bubbles are adhered tends to decrease. In the degassing device 5, as a method for degassing the dissolved gas in the ultrapure water, a method of vacuum degassing via a gas permeable membrane is preferable.

As a method of dissolving ozone gas in ultrapure water, a method of injecting and dissolving ozone gas into ultrapure water via a gas permeable membrane, a method of dissolving ozone gas by bubbling ozone gas in ultrapure water, A method of dissolving ozone gas in water via an ejector, a method of supplying ozone gas upstream of a pump for supplying ultrapure water to the gas dissolving tank 2, and dissolving the ozone gas by stirring in the pump are exemplified. As the ozone gas to be dissolved in ultrapure water in the gas dissolving tank 2, ozone gas generated by reducing hydroxyl ions in ultrapure water by electrolysis of ultrapure water is preferable because of its high purity.

As the gas permeable membrane in the gas dissolving tank 2 and the degassing device 5, a large number of gas permeable materials such as silicon and a water-repellent material such as fluorine resin can be used. For example, a member provided with fine holes and configured to transmit gas but not water can be used. The gas permeable membrane can be used as a hollow fiber structure, and when the gas permeable membrane is formed in a hollow fiber structure, a method of allowing gas to permeate from the inner side of the hollow fiber to the outside as a method of degassing or gas dissolving, Any of the methods of transmitting gas from the outside of the hollow fiber to the inner space side can be adopted.

In the gas dissolving tank 2, ozone gas is dissolved in ultrapure water supplied from the ultrapure water supply pipe 8 to the gas dissolving tank 2 via the gas permeable membrane 9, and the ultrapure water in which the ozone gas is dissolved is It is sent from the supply pipe 10 to the pH adjusting device 3.

After the ozone gas is dissolved in the ultrapure water in the gas dissolving tank 2, the pH is adjusted to be alkaline in the pH adjusting device 3. The cleaning method of the present invention utilizes the fact that ozone in an alkaline cleaning solution is decomposed and organic substances on the surface of a silicon wafer or the like are removed by the decomposed ozone. And the effect of removing organic substances per unit time is improved. However, if the pH is too high, the effect of removing organic substances disappears in a short time. For this reason, the pH of the cleaning solution is preferably adjusted to 11 or less, more preferably adjusted to 9 to 11, particularly preferably 10 to 10.5. For the reasons described above, it is preferable that the ultrapure water in which the ozone gas is dissolved is made alkaline immediately before the cleaning.

In order to adjust the pH, a method is employed in which a liquid or gaseous alkali is dissolved in ultrapure water in which ozone gas is dissolved. As the alkali, an aqueous ammonia solution or ammonia gas is preferable. When a liquid alkali is used for pH adjustment, as shown in FIG. 2, the pH adjustment device 3 can be composed of, for example, an alkali storage tank 11 and a pump 12. A method is adopted in which a liquid alkali is added and mixed in the middle of a pipe for supplying the liquid alkali. In FIG. 2, reference numeral 13 denotes a control valve for adjusting the supply amount of alkali.

When adding a gaseous alkali for pH adjustment, the pH adjusting device 3 can be constituted by, for example, an alkaline gas supply device 14 and a gas dissolving tank 15 as shown in FIG. As the gas dissolving tank 15,
A structure having a gas permeable membrane 9 similar to the gas dissolving tank 2 for dissolving the ozone gas can be used.

The alkaline cleaning liquid whose pH has been adjusted by the pH adjusting device 3 is sent to the cleaning tank 4. As described above, the cleaning liquid is alkaline and has a positive oxidation-reduction potential by dissolving ozone gas. It is necessary to be. Therefore, the cleaning liquid supply pipe 16 for supplying the cleaning liquid to the cleaning tank 4 is provided.
Of oxidation-reduction potentiometer 17 and dissolved ozone concentration meter 1
8. A hydrogen ion concentration meter 19 is provided to constantly monitor the oxidation-reduction potential, dissolved ozone concentration and pH in the cleaning solution, and to measure the amount and pH of ozone gas dissolved in ultrapure water in the gas dissolving tank 2.
It is preferable that the adjusting device 3 be configured so that the amount of alkali added can be controlled.

The method of cleaning the object 6 to be cleaned in the cleaning tank 4 with an alkaline cleaning liquid includes a batch cleaning method in which the object to be cleaned 6 is immersed in the cleaning liquid for cleaning, or a method in which the cleaning liquid is circulated and brought into contact with the object 6 to be cleaned. Circulating cleaning method in which the cleaning liquid is supplied from the bottom side of the cleaning tank 4 and the cleaning liquid is washed while overflowing from the upper part of the cleaning tank 4; And a method of spraying a cleaning liquid onto the cleaning object 6 rotated at a high speed to perform cleaning.

A heater 20 is provided in the cleaning tank 4 so that the temperature of the cleaning liquid can be adjusted as required. In order to obtain a better cleaning effect, the cleaning solution should be 20 ~
It is preferred that the temperature be adjusted to 60 ° C. for washing. It is more effective to use ultrasonic irradiation at the time of cleaning. The ultrasonic wave generated from the ultrasonic irradiation device 7 has a frequency of 30 kHz or more. When irradiating ultrasonic waves, for example, in a batch cleaning method, a method of irradiating the object to be cleaned 6 in a state where the object to be cleaned 6 is immersed in the cleaning liquid supplied into the cleaning tank 4 is adopted. In the case of the method of washing by spraying, a method of irradiating the cleaning liquid with ultrasonic waves at an upstream portion of the cleaning liquid injection nozzle is adopted.

When using ultrasonic irradiation at the time of cleaning, it is preferable that a rare gas is further dissolved in the cleaning liquid. Examples of the rare gas include helium, neon, argon, krypton, and xenon, or a mixture of two or more of them. It is preferable that the rare gas is dissolved in the cleaning solution at 0.05 ppm or more. It is preferable to dissolve the rare gas in a step after degassing dissolved gases such as oxygen gas, nitrogen gas, and carbon dioxide gas in the ultrapure water in the degassing device 5, and dissolve the ozone gas in the ultrapure water. It is preferable that the ozone gas is dissolved in the gas dissolving tank 2 simultaneously or continuously. As a method for dissolving the rare gas, a method similar to the method for dissolving ozone gas in ultrapure water can be employed.

The cleaning apparatus of the present invention preferably has a gas seal structure in order to prevent atmospheric oxygen, nitrogen and the like from being mixed into ultrapure water or the cleaning liquid. In the above-described example, the case where the pH is adjusted by the pH adjuster 3 after dissolving the ozone gas in the ultrapure water in the gas dissolving tank 2 has been described. However, the ozone gas may be dissolved after the pH is adjusted. good. When the ozone gas is dissolved after adjusting the pH, the ozone gas is preferably dissolved immediately before the washing.

[0034]

The present invention will be described below in further detail with reference to examples and comparative examples. Examples 1 to 6, Comparative Examples 1 to 36 A silicon wafer substrate (n-Si100) of 36 inches was prepared.
RCA cleaning to remove impurities on the surface, immersion in 0.5% dilute hydrofluoric acid for 10 minutes, rinsing with ultrapure water for 5 minutes by overflow rinsing method, and further, sulfuric acid hydrogen peroxide at 130 ° C (volume ratio) 98% sulfuric acid: 30% hydrogen peroxide solution = 4:
1 mixture). After rinsing this silicon wafer with ultrapure water and drying, a commercially available polyethylene wrap film is stuck in a clean room for 1 day so that air bubbles do not enter the wafer surface, and the silicon wrap film adheres to the polyethylene wrap film surface. Organic substances were transferred to the surface of the silicon wafer. After peeling off the polyethylene wrap film adhered to the silicon wafer, and measuring the surface contact angle by dropping ultrapure water drops as an index of the degree of organic substance adhesion on the silicon wafer surface, the wafer was washed with the cleaning liquid and conditions shown in Table 2. After drying, the contact angle of the surface was measured again to examine the effect of removing organic substances. The results are shown in Table 2. The surface contact angle of the silicon wafer before contacting and contaminating with the polyethylene wrap film is 2
1 ° (average value of 25 wafers).

[0035]

[Table 2]

Comparative Example 4 Washing was carried out in the same manner as in Examples 1 to 6 and Comparative Examples 1 to 3, except that 5 ppm of ozone was dissolved in ultrapure water as a cleaning liquid. Table 2 shows the measurement results of the contact angles of the wafer surface before and after the cleaning.

Comparative Example 5 Sulfuric acid and hydrogen peroxide solution (98% sulfuric acid in volume ratio)
30% hydrogen peroxide solution = 4: 1 mixture) and 130
Examples 1 to 6 except that washing was performed by a batch method at
And it wash | cleaned similarly to Comparative Examples 1-3. Table 2 shows the measurement results of the contact angles of the wafer surface before and after the cleaning.

Examples 7 to 12 and Comparative Examples 6 to 8 After performing RCA cleaning, dilute hydrofluoric acid cleaning and rinsing with ultrapure water in the same manner as in Examples 1 to 6, a polyethylene wrap film was adhered to the surface. After measuring the contact angle of the surface of the silicon wafer contaminated with organic substances,
After irradiating ultrasonic waves of 1,200 w with z and washing with the washing liquids and conditions shown in Table 3, and drying, the surface contact angle was measured again. The results are shown in Table 3.

[0039]

[Table 3]

Comparative Example 9 Washing was carried out in the same manner as in Examples 1 to 6 and Comparative Examples 1 to 3, except that 5 ppm of ozone was dissolved in ultrapure water as a cleaning liquid. Table 23 also shows the measurement results of the contact angles of the wafer surface before and after the cleaning.

Comparative Example 10 Sulfuric acid hydrogen peroxide solution (98% sulfuric acid in volume ratio:
30% hydrogen peroxide solution = 4: 1 mixture) and 130
Examples 1 to 6 except that washing was performed by a batch method at
And it wash | cleaned similarly to Comparative Examples 1-3. Table 3 shows the measurement results of the contact angles of the wafer surface before and after the cleaning.

[0042]

According to the method of the present invention, in the step of cleaning electronic parts such as silicon wafers, compared with the conventional method of cleaning organic substances with sulfuric acid hydrogen peroxide or ultrapure water in which only ozone gas is dissolved, in the cleaning step. The organic matter on the surface can be reliably removed in a short time. According to the method of the present invention, the amount of chemicals used for cleaning and the amount of ultrapure water used for rinsing after cleaning can be reduced, and the cost of chemicals and ultrapure water can be reduced. It is possible to reduce the waste liquid treatment cost and the like, and thus to reduce the manufacturing cost of electronic component members.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of a cleaning device of the present invention.

FIG. 2 is a configuration diagram illustrating an example of a pH adjusting device.

FIG. 3 is a configuration diagram showing a different example of the pH adjusting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrapure water production apparatus 2 Gas dissolution tank 3 pH adjustment apparatus 4 Cleaning tank 6 Object to be cleaned 7 Ultrasonic irradiation apparatus 18 Dissolved hydrogen concentration meter 19 Hydrogen ion concentration meter

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-166776 (JP, A) JP-A-7-161672 (JP, A) JP-A-7-256260 (JP, A) International Publication 95/6712 (WO, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) B08B 1/00-7/04 H01L 21/304

Claims (9)

(57) [Claims] An electronic component member having a dissolved gas concentration of 10 p.
A method for cleaning electronic parts and components, characterized by dissolving ozone gas in ultrapure water degassed to less than pm and cleaning with an alkaline cleaning liquid having a positive oxidation-reduction potential. 2. The method according to claim 1, wherein the alkaline cleaning liquid dissolves at least 0.05 ppm of ozone gas.
The method for cleaning electronic component members according to the above. 3. The pH of the alkaline cleaning solution exceeds 7, and
3. The method for cleaning electronic component members according to claim 1, wherein: 4. The electronic component members such cleaning method according to any one of claims 1 to 3, characterized in that washing while applying 30kHz ultrasound. 5. The temperature of the alkaline cleaning solution is from 20.degree.
Washing by adjusting the temperature to ℃.
5. The method for cleaning electronic component members according to any one of 4 . 6. The method of cleaning electronic components members acids according to any one of claims 1 to 5, characterized in that dissolving through the gas permeable membrane ozone gas in ultrapure water. 7. An ultrapure water apparatus and a dissolved gas concentration of 10 ppm
Gas dissolving means for dissolving ozone gas in ultrapure water degassed to less than , pH adjusting means for adjusting the solution to alkaline, and positive redox dissolving ozone gas in ultrapure water A cleaning unit for cleaning electronic component members with an alkaline cleaning liquid having a potential; 8. A dissolved ozone concentration detecting means and a pH detecting means for respectively detecting the concentration of dissolved ozone dissolved in the alkaline cleaning liquid and the pH of the solution. 8. The cleaning device for electronic component members according to claim 7 , further comprising a dissolved ozone concentration control means and a pH control means for controlling a dissolved ozone concentration and a pH in the cleaning liquid, respectively. 9. The cleaning section to the electronic component member such cleaning apparatus according to claim 7 or 8, wherein the having the ultrasonic wave irradiation means for irradiating ultrasonic waves.