JP2011205015A - Cleaning method for electronic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive, resource-saving cleaning method that shortens a time needed for peeling processing etc., of, for example, a resist in cleaning of an electronic material and further securely removes resist residues in a short time by wet cleaning after the resist peeling.SOLUTION: Pressure gas with predetermined pressure is supplied by opening a pressure gas control value 19 while opening a carrier gas control value 14 to press a pressure plate 16, carrier gas G in a gas holder 15 is controlled to predetermined pressure to be supplied to a carrier gas supply pipe 7, and cleaning liquid W1 is supplied to a two-fluid nozzle 8 together therewith. A jet of droplets W2 generated from the cleaning liquid W1 and carrier gas G thus mixed by the two-fluid nozzle 8 is brought into contact with a silicon wafer 5 to clean a surface of the silicon wafer 5. The cleaning liquid W1 is preferably a sulfuric acid solution containing sulfuric peroxide obtained by electrolyzing sulfuric acid.

Description

  The present invention effectively cleans electronic materials that require extremely strict control, specifically silicon wafers for semiconductors, glass substrates for flat panel displays, etc. The present invention relates to a cleaning method for removal.

  For the cleaning of a substrate as an electronic component, for example, a high concentration chemical solution or detergent is used as represented by RCA cleaning, and a very large amount of pure water or ultrapure water is used to rinse these chemical solutions. ing. Further, the semiconductor manufacturing process includes a process of locally implanting metal ions as impurities into the surface of the semiconductor wafer. In this step, in order to prevent injection of metal ions into undesired portions, a resist composed of a photosensitive resin material or the like is patterned as a mask material, and ions of the same concentration are also implanted into the resist surface. Since the ion-implanted resist is an unnecessary product in manufacturing, a resist removal process for peeling and removing from the wafer surface is performed.

In such a resist removal process, after the resist is ashed with an ashing device, the resist residue is carried into a cleaning device and removed with a cleaning liquid. However, when the ashing process is performed by the ashing apparatus, there is a problem that a portion not protected by the resist is damaged. With respect to this problem, in Patent Document 1, SPM, which is a mixed solution of sulfuric acid and hydrogen peroxide, is supplied to the wafer surface, and due to the oxidizing power of peroxomonosulfuric acid (H ₂ SO ₅ ) contained in the SPM, It describes that an unnecessary resist is removed by stripping.

  In addition, even when cleaning is performed with SPM, when the ion implantation amount is high, the resist surface may be deteriorated, so that the resist cannot be removed satisfactorily or the resist is removed. It may take time. Therefore, in such a case, in Patent Document 1, an SPM supply nozzle and a two-fluid nozzle for jetting droplets are installed in a single wafer cleaning device, and after supplying the droplet jet, high temperature SPM is supplied. A processing method has been proposed in which the resist is peeled off from the wafer.

  However, the resist stripping process by SPM performs cleaning while maintaining the oxidizing power by mixing sulfuric acid and hydrogen peroxide solution. Therefore, once used, the oxidizing power of the chemical solution decreases. Therefore, when SPM is used in the resist removal process using a single wafer cleaning device, if the chemical solution is circulated and reused, the cleaning power is not stable, and furthermore, a large amount of sulfuric acid and hydrogen peroxide are consumed. There are disadvantages in that the running cost is high and a large amount of waste liquid is generated.

  In order to solve such problems, various efforts have been made with the aim of reducing the cost of the cleaning process, reducing the environmental burden, and improving the cleaning quality. For example, as an alternative to the SPM cleaning solution, the present applicant uses an electrolytic sulfuric acid solution containing an oxidizing substance such as peroxomonosulfuric acid obtained by electrolyzing sulfuric acid as a cleaning solution with a diamond-coated electrode, and uses sulfuric acid in circulation. A cleaning method and a cleaning system are proposed (for example, Patent Documents 2 and 3). With this method, it is expected that the oxidizing power can be easily maintained at a certain level or more, and since there is almost no additional injection of chemical liquid or replacement of chemical liquid, the amount of chemical liquid can be greatly reduced. In addition, since a cleaning solution with a high oxidizing power can be continuously produced, it is possible to realize peeling cleaning (washing without ashing) that does not perform ashing treatment at a later stage depending on conditions, so damage due to ashing In some cases, the quality may be improved.

JP 2005-109167 A JP 2006-114880 A JP 2006-278687A

  In the resist stripping processing method by SPM described in Patent Document 1, since the manufacturing process is complicated and the time required for the manufacturing tends to be long, the time required for each process including the resist stripping process is increased. It is desirable to shorten it. In addition, when resist removal cleaning is performed without ashing using a sulfuric acid solution containing persulfuric acid obtained by electrolyzing a sulfuric acid solution, the resist residue that has not been peeled off tends to remain on the electronic material. It is necessary to perform sufficient cleaning in cleaning, and a large amount of pure water and ultrapure water are consumed, and it is desired to achieve resource saving at low cost by improving cleaning power.

  Therefore, it is conceivable to apply the cleaning methods proposed in Patent Document 2 and Patent Document 3. By this cleaning method, it is possible to reduce the amount of chemical solution used and the amount of waste liquid and at the same time obtain a high cleaning effect. The cleaning method described in Patent Document 3 can also be applied to single wafer cleaning. However, some resists with a large dose amount cannot be removed by simply using a persulfuric acid-containing sulfuric acid solution obtained by electrolyzing a sulfuric acid solution, and improvement in detergency has been a problem. Furthermore, if the cleaning efficiency of electronic materials in general can be improved, the industrial utility value is very high.

  The present invention has been made in view of the above problems, and an object thereof is to provide a cleaning method capable of saving resources of electronic materials at low cost. In particular, an object of the present invention is to provide a cleaning method capable of shortening a time required for, for example, a resist stripping process and further reliably removing a resist residue in a short time by wet cleaning after resist stripping.

  In order to solve the above-mentioned problems, the present invention provides a method for cleaning an electronic material, wherein the electronic material is cleaned by bringing a jet of droplets generated from a cleaning liquid and a gas into contact with the electronic material. (Claim 1).

  According to the above invention (invention 1), the surface of the electronic material is cleaned by bringing a jet of droplets generated from the cleaning liquid and gas into contact with the electronic material, so that the cleaning power is higher than that of cleaning with only the cleaning liquid. Since it improves greatly, the organic substance etc. of the surface of an electronic material can be wash | cleaned simply and rapidly.

  In the said invention (invention 1), the said washing | cleaning liquid is 1 type of liquid chosen from the group which consists of a sulfuric acid, the sulfuric acid hydrogen peroxide aqueous solution mixture and ozone-dissolved sulfuric acid, and the washing | cleaning liquid obtained by electrolyzing a sulfuric acid, or 2 It is preferable to comprise a mixed solution of seeds or more (claim 2).

  According to the said invention (invention 2), since the cleaning power of these chemical | medical solutions can be improved, even the resist etc. on electronic materials, such as a silicon wafer, can be removed effectively.

  Moreover, in the said invention (invention 1), it is preferable that the said washing | cleaning liquid consists of 1 type of liquid chosen from the group which consists of ozone water, oxygen water, nitrogen water, hydrogen water, and the water which warmed these (invention). Item 3).

  According to the said invention (invention 3), since the detergency of these chemical | medical solutions can be improved, the organic substance etc. on an electronic material can be removed effectively, and it can clean.

  In the said invention (Invention 1-3), the said gas is 1 type of gas chosen from the group which consists of nitrogen, oxygen, a noble gas, hydrogen, a carbon dioxide, ozone, clean air, and water vapor, or 2 or more types of mixture A gas is preferred (Claim 4).

  According to the above invention (invention 4), the surface of the electronic material is cleaned by bringing a jet of droplets generated from these gases and the cleaning liquid into contact with the electronic material, thereby cleaning the surface of the electronic material. In addition, since the cleaning power is improved, organic substances on the surface of the electronic material can be easily and quickly cleaned.

  In the said invention (invention 1-4), it is preferable that the supply temperature of the said gas is 80-200 degreeC (invention 5).

  According to the above invention (invention 5), the electronic material can be cleaned by a jet of droplets generated from the cleaning liquid and gas without lowering the temperature of the cleaning liquid.

  In the said invention (invention 1-5), it is preferable that the supply temperature of the said washing | cleaning liquid is 60-180 degreeC (invention 6).

  According to the said invention (invention 6), an electronic material can be efficiently cleaned in a short time by a high-temperature cleaning liquid.

  In the said invention (invention 1-6), it is preferable that the said electronic material is fixed to a rotation apparatus, and single wafer washing | cleaning is carried out (invention 7).

  According to the above invention (invention 7), it is possible to efficiently perform spin cleaning for each single wafer in which a jet of cleaning liquid or droplets is directed toward the surface of the electronic material while rotating the electronic material.

  According to the electronic material cleaning method of the present invention, the surface of the electronic material is cleaned by bringing a jet of droplets generated from the cleaning liquid and gas into contact with the electronic material, which is much higher than cleaning with only the cleaning liquid. Since the detergency is improved, organic substances on the surface of the electronic material can be easily and quickly washed. As this cleaning solution, a sulfuric acid solution containing persulfuric acid obtained by electrolyzing sulfuric acid is preferable.

It is a flowchart which shows the washing | cleaning system which can apply the washing | cleaning method of the electronic material which concerns on one Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a flowchart showing a cleaning system to which a wet cleaning method that is a method for cleaning an electronic material according to an embodiment of the present invention can be applied.

  In FIG. 1, the electronic material cleaning system includes a single wafer cleaning device 1 and a cleaning fluid supply device 2. The single wafer cleaning apparatus 1 has a configuration in which a rotating device 4 is installed in a chamber 3, and a silicon wafer 5 as an electronic material as an object to be cleaned is fixed to a rotating table 4 </ b> A of the rotating device 4. Yes. The chamber 3 is preferably configured to be evacuated from below. The method for fixing the silicon wafer 5 to the turntable 4A is not particularly limited, but a method (vacuum chuck) in which the inside of the turntable 4A is brought into a reduced pressure state and the silicon wafer 5 is brought into close contact with the turntable 4A is preferable. In this case, a method of providing a space with Teflon rubber or a fluorine-based elastomer (perfluoroelastomer) on the contact surface between the turntable 4A and the silicon wafer 5 and reducing the pressure to bring the turntable 4A and the silicon wafer 5 into close contact with each other is preferable. .

  The cleaning fluid supply device 2 includes a cleaning liquid supply pipe 6 connected to a cleaning liquid source (not shown), a carrier gas supply pipe 7, and an internal mixing type two-fluid nozzle 8 to which both pipes are connected. The cleaning liquid supply pipe 6 is provided with a cleaning liquid control valve 9 from the upstream side and a joint 11 to which a supply liquid pressure gauge 10 for measuring the supply pressure of the cleaning liquid W1 is attached. The liquid contact portion of the two-fluid nozzle 8 is desirably a member having high heat resistance and chemical resistance, and fluororesin, quartz, or the like is preferable.

  Further, the carrier gas supply pipe 7 is provided with a joint 13 to which a carrier gas pressure gauge 12 is attached from the upstream side and a carrier gas control valve 14, and its base end is connected to a gas storage tank 15. Yes. The gas storage tank 15 has a sealed structure formed by the carrier gas adjusting container A and the pressurizing plate 16 and having a variable volume. The carrier raw material gas supply pipe 18 including the carrier raw material gas control valve 17 extends. Exist. The carrier gas raw material gas supply pipe 18 communicates with the gas storage tank 15 through the carrier gas adjustment container A and the pressure plate 16 while maintaining the sealed state of the carrier gas adjustment container A and the gas storage tank 15. Further, an outer space formed by the pressurizing plate 16 and the carrier gas adjusting container A is connected to a pressurized gas source (not shown), and a pressurized gas control valve 19 and a pressurized gas pressure gauge 20 are attached on the way. A pressurized gas supply pipe 22 provided with the joint 21 is provided, and an exhaust pipe 24 provided with an exhaust valve 23 is provided midway. The gas storage tank 15 is provided with a heater 25 connected to a control mechanism (not shown) so that the carrier gas G can be controlled to a predetermined temperature described later. In addition, a PFA tube etc. can be used as these various piping.

  Here, the supply pressure of the carrier gas G is displayed by the carrier gas supply pressure gauge 12, but it is necessary to make it higher than the supply water pressure L of the cleaning liquid W1. As a guide, the carrier gas supply pressure (O) is preferably about 0.1 to 0.2 MPa higher than the nozzle feed water pressure (L) of the cleaning liquid. The carrier gas G is preferably supplied to the two-fluid nozzle 8 for 5 to 30 seconds.

  For this reason, it is necessary to store and supply a sufficient amount of carrier gas G to the gas storage tank 15. Specifically, when the supply time of the carrier gas G to the two-fluid nozzle 8 is 10 seconds and the cleaning interval is 5 minutes, it is desirable to supply the carrier gas G at a flow rate of 100 to 300 NL / min. For example, when the flow rate of the carrier gas G is 120 NL / min, the carrier gas amount (V (L)) required for one cleaning is represented by the following formula (1).

  V (L) = 120 (NL / min) ÷ 60 × 10 (seconds) = 20 (L, standard state) (1)

  Therefore, it is desirable that the gas storage tank 15 has a volume (maximum volume) that sufficiently exceeds the above formula (1), and considering the margin on the device, it is about 30 L, which is 1.5 times the required amount. desirable. Note that. Even if the volume of the gas storage tank 15 is increased too much, it is not meaningful and the efficiency of the heater 25 is deteriorated, so that it is about twice or less at the maximum.

  In the cleaning system having the above-described configuration, the cleaning liquid W1 can be arbitrarily selected depending on the electronic material to be cleaned and the cleaning purpose. For example, sulfuric acid, sulfuric acid / hydrogen peroxide mixture (SPM) and One type of liquid selected from the group consisting of ozone-dissolved sulfuric acid (SOM) and a cleaning liquid obtained by electrolyzing sulfuric acid, or a mixture of two or more types can be used.

In particular, when the object to be cleaned is a silicon wafer 5 as in this embodiment, a cleaning liquid obtained by electrolyzing sulfuric acid is preferable. The cleaning liquid obtained by electrolyzing this sulfuric acid can be produced as a sulfuric acid solution containing persulfuric acid by electrolyzing the sulfuric acid with an electrolysis reactor (not shown). Here, persulfuric acid refers to peroxomonosulfuric acid (H ₂ SO ₅ ) and peroxodisulfuric acid (H ₂ S ₂ O ₈ ). Both peroxomonosulfuric acid and peroxodisulfuric acid have high oxidizing power.

In an electrolytic reaction apparatus, electrolysis is performed with a pair of an anode and a cathode. The material of this electrode is not particularly limited. However, when platinum, which is widely used as an electrode, is used as an anode, persulfuric acid cannot be efficiently produced and platinum is eluted. . Therefore, in this embodiment, a conductive diamond electrode is used as at least the anode of the electrode. It is known that peroxodisulfate ions can be generated from sulfate ions or hydrogen sulfate ions using a conductive diamond electrode under conditions of a current density of about 0.2 A / cm ² (Ch. Comninellis et al., Electrochemical and Solid-State Letters, Vol.3, No.2, pp.77-79, 2000).

As the conductive diamond electrode, a semiconductor material such as a silicon wafer is used as a substrate, and a conductive diamond thin film is synthesized on the surface of the substrate to a thickness of 20 μm or more, or a self-stand that is deposited and synthesized in a plate shape without using a substrate. Type conductive polycrystalline diamond. The conductive diamond thin film is one obtained by doping boron or nitrogen during the synthesis of the diamond thin film and imparting conductivity, and usually one doped with boron. If the doping amount is too small, the technical significance does not occur. If the doping amount is too large, the doping effect is saturated. Therefore, a doping amount in the range of 50 to 20000 ppm with respect to the carbon amount of the diamond thin film is suitable. As the conductive diamond electrode, a plate-like one is usually used, but a plate having a network structure can also be used. In the electrolytic treatment in this electrolytic reaction apparatus, the current density on the surface of the conductive diamond electrode is 10 to 100000 A / m ² , the concentrated sulfuric acid is contacted in the direction parallel to the diamond electrode surface, and the liquid flow rate is 10 to 10,000 m / h. It is desirable to have it processed.

In the cleaning liquid obtained by electrolyzing the sulfuric acid thus produced, the concentration of sulfuric acid is 80 to 96% by mass (persulfuric acid concentration 2 to 20 [g / L (as S ₂ O ₈ )]). It is preferable to do so. When the concentration of persulfuric acid is less than 2 [g / L (as S ₂ O ₈ )], the oxidizing power is insufficient, and a sufficient cleaning effect of the silicon wafer 5 such as a resist peeling effect cannot be obtained, while 20 [g / L ( As S ₂ O ₈ )] is exceeded, it is inefficient in terms of current efficiency.

  Further, ozone water, oxygen water, nitrogen water, hydrogen water or other gas-dissolved water, or warm water obtained by heating these can be used as the cleaning liquid W1.

  The cleaning liquid W1 as described above is preferably heated to 60 to 180 ° C., although it depends on the type of cleaning liquid used.

  Further, as the carrier gas G, one kind of gas selected from the group consisting of nitrogen, oxygen, rare gas, hydrogen, carbon dioxide, ozone, clean air, water vapor and the like is used alone, or two or more kinds are mixed. Can be used.

  Next, cleaning of the electronic material of this embodiment using the electronic material cleaning system, the cleaning liquid W1 and the carrier gas G as described above will be described.

  First, a carrier raw material gas is supplied to a gas storage tank 15 from a carrier raw material gas source (not shown) via a carrier raw material gas supply pipe 18. This carrier source gas is supplied in a state of being controlled to a predetermined flow rate and pressure by the carrier source gas control valve 17. At this time, the exhaust valve 23 is opened, and when the air in the space above the pressurizing plate 16 is discharged from the exhaust pipe 24 to the outside of the system, the pressurizing plate 16 rises and the volume of the gas storage tank 15 increases. Further, the carrier material gas in the gas storage tank 15 is heated by the heater 25. The carrier source gas is preferably heated to 80 to 200 ° C., particularly 100 to 180 ° C. by the heater 25. As a result, the temperature of the carrier gas G supplied from the gas storage tank 15 becomes substantially the same temperature as this, but the cleaning liquid W1 is heated to 60 to 180 ° C. by setting the carrier gas G to such a temperature. However, even if mixed with the carrier gas G in the two-fluid nozzle 8, the temperature of the cleaning liquid W1 does not decrease.

  Subsequently, when the carrier gas control valve 14 is opened, the pressurized gas control valve 19 is opened at the same time, and the pressurized plate 16 is pressed by supplying the pressurized gas at a predetermined pressure. The gas G is supplied to the carrier gas supply pipe 7 at a predetermined pressure. The carrier gas G is adjusted to a predetermined flow rate by the carrier gas control valve 14 and supplied to the two-fluid nozzle 8. In the present embodiment, since the cleaning time is 5 minutes, the flow rate is 5 NL / min for 4 minutes (20 L (standard state)), and a preliminary time of 1 minute is provided to supply to the two-fluid nozzle 8.

  At the same time, the cleaning liquid W1 is supplied to the two-fluid nozzle 8. The amount of the cleaning liquid W1 cleaning fluid is preferably 0.05 to 0.5 L / min, and preferably about 0.1 to 0.4 L / min. Further, the supply liquid pressure of the cleaning liquid W1 is desirably about 0.05 to 0.5 MPa, and preferably about 0.1 to 0.4 MPa. The supply temperature of the cleaning liquid W1 is preferably 60 to 180 ° C., particularly preferably 80 to 160 ° C., with heating in advance.

  The carrier gas G and the cleaning liquid W1 as described above may be supplied by appropriately controlling the flow rate so that the carrier gas G becomes 10 to 10,000 with respect to the volume 1 of the cleaning liquid W1.

  Then, the surface of the two-fluid nozzle 8 is cleaned by bringing a jet of droplets W2 generated by jetting the cleaning liquid W1 and the carrier gas G while mixing them into contact with the silicon wafer 5. At this time, the turntable 4A is rotated at 10 to 500 rpm, preferably 100 to 300 rpm. Thereby, the silicon wafer 5 can be effectively cleaned. At this time, in the present embodiment, the chamber 3 is configured to be evacuated from below, so that the mist caused by the jet of the droplet W2 discharged from the two-fluid nozzle 8 does not rise in the chamber 3, It is possible to prevent the droplet W2 from adhering to and contaminating the silicon wafer 5 that is the object to be cleaned.

  When the chemical solution cleaning step is completed in this manner, rinsing cleaning with rinsing water may be performed as necessary. As the rinse water, ultrapure water is usually used. Here, the ultrapure water is, for example, fine particles having an electrical resistivity of 18 MΩ · cm or more, a metal ion concentration of 5 ng / L or less, a residual ion concentration of 10 ng / L or less, and 0.1 μm or more in 1 mL. This refers to water having a quality of 5 or less and a TOC of 0.1 to 10 μg / L. Further, wet cleaning may be performed. In this wet cleaning, the silicon wafer 5 may be cleaned with pure water or functional water in which various gases are dissolved.

  After the above cleaning, spin resisting, IPA drying, and the like are performed according to a conventional method to complete a series of resist peeling cleaning and removing processes, and the electronic material from which the resist has been removed is sent to the next step.

  By repeating such operations continuously or intermittently, the silicon wafers 5 can be sequentially processed. Note that the above operation may be repeated a plurality of times for a single silicon wafer 5.

  As mentioned above, although this invention has been demonstrated based on the said embodiment, this invention is not limited to the said embodiment.

  In the above embodiment, the case where ashing is not performed on the silicon wafer 5 has been described. However, ashing may be performed prior to cleaning with the cleaning liquid. The ashing process is performed by ashing the resist on the electronic material with oxygen plasma or the like according to a conventional method. However, in the present invention, the persulfuric acid-containing sulfuric acid solution produced by electrolysis of the sulfuric acid solution can be used to reliably remove the resist without causing a problem of resist residue even if the ashing process is omitted. By omitting the ashing process, the time and cost required for a series of resist stripping processes can be greatly reduced.

  In the present embodiment, the case of the silicon wafer 5 has been described as the electronic material. However, the present invention can also be applied to other electronic materials such as a flat panel display.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

[Example 1]
Using the apparatus shown in FIG. 1, a pattern is formed using a KrF excimer laser as an electronic material, and a resist is formed at an As ion implantation concentration of 1E + 15 [atoms / cm ² ]. A test for stripping and removing the resist was conducted under the following conditions.

<Cleaning conditions>
Two-fluid nozzle 8: manufactured by Spraying Japan, two-fluid nozzle cleaning solution W1: electrolytic sulfuric acid solution having a sulfuric acid concentration of 85% (persulfuric acid concentration: about 5 g / L (as S ₂ O ₈ ), temperature 150 immediately before the two-fluid nozzle 8 ℃)
Carrier gas G: Nitrogen gas (heating temperature 160 ° C.)
Supply amount of cleaning liquid W1: 0.4 L / min Nozzle supply water pressure of cleaning liquid W1: 0.2 MPa
Supply pressure of carrier gas G: 0.3 MPa
Number of rotations of rotating table 4A during cleaning: 100rpm
Washing time (1 swing): 10 seconds

  Under the above-mentioned cleaning conditions, liquid supply from the two-fluid nozzle 8 to the center of the silicon wafer 5 is started, and the movement of moving from the center to the end of the silicon wafer 5 is performed for 10 seconds as one swing. I went 5 swings. When the resist removal behavior before and after cleaning was observed with a laser microscope, it was confirmed that the resist could be peeled off on the entire wafer surface. From Example 1, it was confirmed that the resist can be completely stripped and removed without ashing by two-fluid cleaning with an electrolytic sulfuric acid solution and nitrogen gas.

[Comparative Example 1]
In Example 1, pure water was used as the cleaning liquid W1, but the resist could not be removed at all.

[Example 2]
In Example 1, the cleaning liquid W1 was made into warm ozone water of 60 ° C. at a concentration of 30 mg / L, and a regenerated product without dose as a silicon wafer to be cleaned, a so-called rework product, was used in the same manner as in Example 1. When cleaning was performed and the resist removal behavior before and after cleaning was observed with a laser microscope, the resist could be removed on the entire wafer surface. From this Example 2, it was confirmed that in the case of a reworked product, the resist can be completely stripped and removed without ashing by two-fluid cleaning with warm ozone water.

[Comparative Example 2]
In Example 2, pure water was used as the cleaning liquid W1, but the resist could not be removed at all.

4 ... rotating device 4A ... rotating table (rotating device)
5. Silicon wafer (electronic material)
G ... Carrier gas (gas)
W1 ... cleaning liquid W2 ... droplet generated from cleaning liquid and gas

Claims (7)

  A method of cleaning an electronic material, wherein the electronic material is cleaned by bringing a jet of droplets generated from the cleaning liquid and gas into contact with the electronic material.   The cleaning liquid is composed of one type of liquid selected from the group consisting of sulfuric acid, a sulfuric acid / hydrogen peroxide mixture, ozone-dissolved sulfuric acid, and a cleaning liquid obtained by electrolyzing sulfuric acid, or a mixture of two or more. The method for cleaning an electronic material according to claim 1.   2. The method for cleaning an electronic material according to claim 1, wherein the cleaning liquid is made of one liquid selected from the group consisting of ozone water, oxygen water, nitrogen water, hydrogen water, and water obtained by heating them. .   The gas is one gas selected from the group consisting of nitrogen, oxygen, rare gas, hydrogen, carbon dioxide, ozone, clean air and water vapor, or a mixed gas of two or more. 4. The method for cleaning an electronic material according to any one of 3 above.   The method for cleaning an electronic material according to any one of claims 1 to 4, wherein a supply temperature of the gas is 80 to 200 ° C.   The method for cleaning an electronic material according to claim 1, wherein a supply temperature of the cleaning liquid is 60 to 180 ° C.   The method of cleaning an electronic material according to any one of claims 1 to 6, wherein the electronic material is fixed to a rotating device and subjected to single wafer cleaning.

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