JP3013032B2 - How to clean the object to be cleaned - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for cleaning an object to be cleaned. More specifically, the present invention relates to a method for cleaning an object to be cleaned that can be suitably used for cleaning an object to be cleaned such as a sliced wafer, an electronic component such as a lead frame, and a mechanical component.

[0002]

2. Description of the Related Art As an object to be cleaned composed of a plurality of plate-like materials arranged such that plate-like surfaces are adjacent to each other with a gap therebetween, there are semiconductors and crystals such as silicone, gallium / arsenic, gallium / phosphorus and the like. A process in which a sheet-like bundle of wafers obtained by slicing materials such as quartz, quartz, glass, and other electronic components, as well as parts obtained by stamping a metal plate, are attached to the surface of the sheet metal. There is a plate-shaped material bundle or the like of parts that are in close contact with each other due to the surface tension of oil and have a gap of several μm to several tens μm.

When using these objects to be cleaned,
Generally, in order to remove dirt and the like attached to the gaps between the plate-like materials, to separate the plate-like materials from each other in order to prevent the plate-like materials from sticking to each other, and to improve the handleability at the time of processing, the above-described cleaning is performed. Washing things.

[0004] The object to be cleaned has conventionally been Freon R-113.
, And a chlorinated organic solvent such as 1,1,1-trichloroethane, which is cleaned by ultrasonic waves.

However, the use of fluorocarbon and chlorinated organic solvents has been regulated from the viewpoint of atmospheric environment protection, and there is an urgent need to develop a cleaning technique using a cleaning agent that can be substituted for these.

Therefore, a method for cleaning an object to be cleaned without using chlorofluorocarbon or a chlorine-based organic solvent has been proposed.
A method has been proposed in which, after roughly cleaning a block-shaped object to be cleaned in which plate-like materials are bundled, the plate-like materials are separated into single pieces, precisely cleaned, and after cleaning, bundled again and bundled in a block shape. ing.

[0007] However, the above method requires not only a complicated operation of unblocking the block-shaped object to be cleaned in which the plate-like materials are bundled but then bundling them again, and also requires a large space for cleaning. Is required.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and does not require chlorofluorocarbon or a chlorinated organic solvent for cleaning. It is an object of the present invention to provide a method capable of efficiently removing dirt from the object to be cleaned while keeping the object to be cleaned intact.

[0009]

The gist of the present invention is to provide a plate-like material.
Gap between the holds in the gas to be cleaned in which a plurality of plate-like member plate-like surface provided with a clearance is disposed such that adjacent to each other are bundled so as to be 10 to 500 [mu] m, and the nozzle
And using a nozzle spray pattern is fan-shaped with an aqueous washing liquid that will be ejected from the nozzle, in contact with the entire surface of the plate surfaces adjacent to each other, the aqueous washing solution in the gap between the plate-like material from the nozzle The present invention relates to a method for cleaning an object to be cleaned, which is characterized by spraying.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the method for cleaning an object to be cleaned of the present invention, the gap between the plate-like materials is set to 10 to 500 μm.
A plate-like surface to be cleaned the plate-like member of the plurality arranged such that adjacent are bundled together and held in air by providing a gap, use the nozzle spray pattern is fan-shaped as a nozzle
There, an aqueous cleaning solution that will be injected from the nozzle, each other so as to contact the entire surface of the adjacent plate surfaces, characterized in that to inject the aqueous washing solution in the gap between the plate-like material from the nozzle.

As the object to be cleaned which can be applied to the cleaning method of the present invention, there is used an object to be cleaned comprising a plurality of plate-like members arranged such that a plate-like surface is adjacent to each other with a gap.

Specific examples of the object to be cleaned include, for example,
Examples include a metal plate to which a processing oil has adhered, a bundled metal plate, a substrate obtained by slicing a columnar material to obtain a flat plate, and a component in which a flat plate to which oily dirt has adhered is uniformly arranged in a jig. Examples of the metal plates to which the processing oil is attached and bundled are, when the metal plates are bundled after processing such as stamping, the metal plates adhered to each other by the surface tension of the oily dirt attached to the surface. Blocks. Examples of a substrate obtained by slicing a columnar object to obtain a flat plate include semiconductors and crystal materials such as silicone, gallium / arsenic, and gallium / phosphorus, electronic component-related materials such as quartz, quartz, glass, piezoelectric materials, and ferrite. , Magnetic materials such as samarium / cobalt, magnetic materials such as magnetic heads, inorganic materials such as ceramics,
Plates, wafers, and the like obtained by slicing an ingot with an inner peripheral blade type or band saw type cutting device or the like can be given. Further, as a component in which a flat plate with oily dirt is uniformly arranged on a jig, there is a component in which a liquid crystal panel having a liquid crystal adhered in a gap is horizontally arranged in a jig. The cleaning method of the present invention exhibits excellent cleaning properties, especially for a sliced silicone wafer and a stamped lead frame.

[0013] Examples of the shape of the plate-like material include a disk shape, a square shape, an irregular shape, and the like, but the present invention is not limited only to such a shape.

[0014] The size and thickness of the plate-like material are not particularly limited either, but usually the size is about 20 to 500 mm and the thickness is about 0.1 to 30 mm.

The gap between the plate-like materials is 10 to 500 μm.
m is preferable from the viewpoint of exhibiting an excellent cleaning effect by the cleaning method of the present invention.

Examples of the stains interposed in the gap include those containing oily stains and the like, but the present invention is not particularly limited in the type of the object to be cleaned. The oily soil is not particularly limited, but is preferably, for example, an oily soil having a property of dissolving or emulsifying when washed with an aqueous washing liquid. Examples of the oily stain include cutting oil, rolling oil, grease, liquid crystal, flux, wax, and the like. Even if these oily stains contain solids, the cleaning method of the present invention exhibits an excellent cleaning effect.

The aqueous cleaning solution used in the cleaning method of the present invention contains water. Therefore, since the aqueous cleaning liquid does not have a risk of ignition unlike a solvent-based cleaning liquid containing, for example, a terpene-based solvent, a hydrocarbon-based solvent, an alcohol-based solvent, etc., it is excellent in safety and requires fire prevention equipment. There is an advantage that it does not.

The form of the aqueous cleaning liquid is not particularly limited, and examples thereof include a uniform aqueous solution, an emulsion, and a dispersion such as a suspension.

A typical example of the aqueous cleaning liquid is an aqueous cleaning liquid containing water and a surfactant.

Among the aqueous cleaning solutions containing water and a surfactant, when an aqueous cleaning solution is applied to a lead frame or a silicone wafer, hydrocarbons, polyalkylene oxides, nonionic surfactants and water are specified. It is preferable to use an aqueous cleaning solution obtained by mixing at a ratio of

Representative examples of the hydrocarbon include, for example,
Those having 10 to 18 carbon atoms are exemplified. Specific examples of such hydrocarbons include, for example, decane, dodecane,
Tetradecane, hexadecane, octadecane, decene,
Linear or branched unsaturated hydrocarbons such as dodecene, tetradecene, hexadecene and octadecene; alkylbenzenes such as nonylbenzene and dodecylbenzene;
Naphthalene compounds such as methylnaphthalene and dimethylnaphthalene; and cyclo compounds such as cyclodecane and cyclododecene. Among these hydrocarbons, a saturated or unsaturated hydrocarbon having a straight or branched chain having 12 to 18 carbon atoms is preferable, and olefin hydrocarbons are particularly preferable in consideration of detergency, handleability, and the like. .

In the above aqueous cleaning liquid, the content of hydrocarbon is desirably 2.5 to 65% by weight, preferably 3 to 60% by weight, from the viewpoint of detergency and rinsing properties.

As a typical example of the polyalkylene oxide, for example, a compound represented by the following general formula (I): R ¹ —O— (C _k H _{2 k} O) _j —H (I) (wherein, R ¹ has 1 to ¹ carbon atoms) A polyalkylene oxide represented by the following formula (II): R ² —O— (C _m H _2m O) _n —R ³ (II) (wherein, R ² and R ³ each independently have 1 to 1 carbon atoms)
A hydrocarbon group of 8, m is 2 or 3, and n is an integer of 1 to 3).

In the polyalkylene oxide represented by the general formula (I), R ¹ is a hydrocarbon group having 1 to 8 hydrocarbons. When the carbon number is too large, the solubility in water is reduced and the viscosity becomes too high. Therefore, the carbon number is 8 or less, preferably 3 to
6 is desirable.

Specific examples of R ¹ include, for example, methyl, ethyl, propyl, isopropyl, allyl, butyl, isobutyl, hexyl, 2-ethylhexyl, octyl, phenyl, benzyl And the like.

J represents an integer of 1 to 3. If j exceeds 3, the viscosity may increase and the workability may decrease.

[0027] The content of the polyalkylene oxide represented by the general formula (I) in the aqueous cleaning liquid is 1.5 from the viewpoint of detergency, rinsing property and releasability between sheet materials.
The content is desirably about 45% by weight, preferably 3% to 40% by weight.

In the polyalkylene oxide represented by the general formula (II), R ² and R ³ are each a hydrocarbon group having 1 to 8 carbon atoms. When the number of carbon atoms is too large, the solubility in water is reduced and the viscosity becomes too high. Therefore, the number of carbon atoms is preferably 1 to 4.

Specific examples of R ² and R ³ include, for example, methyl, ethyl, propyl, isopropyl, allyl, butyl, isobutyl, hexyl,
Examples thereof include a 2-ethylhexyl group, an octyl group, a phenyl group, and a benzyl group.

The above n represents an integer of 1 to 3. When n exceeds 3, the viscosity may increase and the workability may decrease.

The content of the polyalkylene oxide represented by the general formula (II) in the aqueous cleaning solution is 0.5 to 0.5 from the viewpoint of detergency, rinsing property and releasability between sheet materials.
It is desirable that the content be 15 to 15% by weight, preferably 1 to 10% by weight.

As a typical example of the nonionic surfactant, those having an average HLB of 4 to 18 are preferable.
Specific examples of such a nonionic surfactant include, for example,
Examples thereof include polyoxyethylene alkyl ether, sorbitan monoalkyl ester, polyoxyethylene sorbitan monoalkyl ester, and polyoxyethylene sorbitan trialkyl ester.

In the aqueous cleaning solution, the content of the nonionic surfactant is 0.5 to 0.5 from the viewpoint of detergency and rinsing property.
It is desirable that the content be 30 to 30% by weight, preferably 1 to 25% by weight.

The water is not particularly limited, but usually includes tap water, ion-exchanged water, pure water and the like.

In the aqueous cleaning solution, the water content is
From the viewpoint of preventing danger such as ignition during the washing operation, 3 to 95% by weight, preferably 7 to 93.
Desirably, it is 5% by weight.

The aqueous washing liquid may optionally contain, for example, a builder, a chelating agent, a rust preventive, an antifoaming agent, and various alkaline substances.

The aqueous cleaning liquid is sprayed from the nozzle into the gap between the plate-like materials so that the aqueous cleaning liquid sprayed from the nozzle comes into contact with the entire surface of the plate-like material constituting the object to be cleaned. Let it.

At this time, an air jet method in which the object to be cleaned is held in the air and an aqueous cleaning liquid is jetted from the nozzle to the object to be cleaned in the air at a high pressure is preferable. When such an aerial spraying method is adopted, the aqueous cleaning liquid is forcibly fed into the gap between the plate-like materials, which is excellent in the effect of washing out dirt and, at the same time, the distance between the adjacent plate-like materials is increased. This is preferable because it is spread out by the pressure and removal of dirt generated between the plate-like materials is promoted .

The type of the nozzle is not particularly limited.
Examples of the nozzle include a nozzle having a spray pattern such as a fan shape, a filled cone shape, an empty cone shape, a filled pyramid shape, an empty pyramid shape, and a direct injection shape. Here, the ejection pattern refers to a cross-sectional shape of an ejection area of the cleaning agent aqueous solution ejected from the nozzle in a direction perpendicular to the nozzle direction.

As shown in FIG. 1A, among the nozzles, when the aqueous cleaning liquid is sprayed in the air, a fan-shaped spray pattern 1 whose major axis a is linear is formed. As shown in FIG. 1B, it is preferable to form a fan-shaped injection pattern 1 whose major axis a is an arc-shaped curve. A nozzle exhibiting such a fan-shaped spray pattern 1 has a spraying rate of the aqueous cleaning liquid sprayed from the nozzles is the same as that of the full-cone or empty-cone spray pattern. There is an advantage that the applied physical detergency increases and the cleaning effect can be improved. Among the nozzles exhibiting the injection patterns shown in FIGS. 1A and 1B, the ratio (a /
b) is preferably 5/1 to 500/1.

In the case where a nozzle having a fan-shaped spray pattern is used, as shown in FIG. 2, the major axis a of the spray pattern is positioned with respect to the gap between the plate members 3 and 4 constituting the object to be cleaned. It is preferable to arrange the nozzles 2 so as to be vertical. When the nozzles 2 are arranged in this manner, the aqueous cleaning liquid easily flows between the plate-shaped members 3 and 4.
There is an advantage that an excellent cleaning effect can be exerted on the dirt 5 between the four.

As shown in FIG. 3, the aqueous cleaning liquid is ejected from the nozzle 2 at an ejection angle θ. The injection angle θ refers to an angle in the major axis direction of the injection pattern 1 when the injection pattern 1 has a fan shape, an elliptical shape, or the like.

The spray angle θ depends on the pressure at the time of spraying the aqueous cleaning liquid, but there is a possibility that the physical stress due to the aqueous cleaning liquid applied per unit area of the cleaning object becomes excessive and the cleaning object is damaged. In order to eliminate and eliminate the need for a large number of nozzles to bring the aqueous cleaning solution into contact with the entire surface of the plate-like material, the spray pattern 1 is filled cone, empty cone, filled pyramid or empty. When the shape is a pyramid, it is preferably 20 degrees or more, and preferably 30 degrees or more. When the shape is a fan, the major axis angle and the minor axis angle are each 20 degrees.
Degree, preferably 30 degrees. In order to enhance the cleaning effect by preventing the physical cleaning power of the aqueous cleaning liquid to be sprayed on the object to be cleaned from decreasing, the spray pattern 1 has a conical shape, In the case of a hollow conical shape, a full pyramid shape, or a hollow pyramid shape, the angle is desirably 90 degrees or less, preferably 60 degrees or less, and the minor axis angle is desirably 20 degrees or less, preferably 10 degrees or less.

The diameter of the orifice of the nozzle hole is not particularly limited. However, usually, the amount of the aqueous cleaning liquid sprayed on the object to be cleaned is set to an amount suitable for cleaning, and the orifice diameter is set to 0.1 in order to prevent the operating pressure from increasing. It is preferably at least 5 mm, especially at least 1 mm, and more preferably at most 10 mm, especially at most 5 mm, in order not to require a large-scale liquid supply device for spraying a large amount of aqueous cleaning liquid. When the shape of the nozzle hole does not have a perfect circle such as an ellipse, the geometric mean of the major axis and the minor axis is defined as the orifice diameter.

When the aqueous cleaning liquid is jetted from the nozzle, the jetting speed from the nozzle is 5 m / sec or more, preferably 20 m / sec, in order to effectively feed the aqueous cleaning liquid into the gap between the plate-like materials and to enhance the cleaning property. Desirably, it is not less than seconds.
The upper limit of the injection speed is preferably 100 m / sec or less from the viewpoint of preventing damage to the object to be cleaned.

A typical example of an apparatus for supplying an aqueous cleaning liquid to the nozzle is a pump. Examples of such a pump include a centrifugal pump, a gear pump, a piston pump, a plunger pump, a diaphragm pump, and the like.

The distance (shortest distance) from the nozzle to the object to be cleaned is not particularly limited as long as the aqueous cleaning liquid hits the tip of the plate-like material constituting the object to be cleaned.
Usually, the distance from the nozzle to the object to be cleaned (the shortest distance)
Is preferably within 30 cm, preferably within 20 cm.

The number of nozzles used for cleaning an object to be cleaned depends on the aspect of the method for cleaning an object to be cleaned according to the present invention. When a plurality of the nozzles are used, the number of the nozzles may be any number as long as the aqueous cleaning liquid can come into contact with the entire surface of the plate-shaped surface which is usually arranged so as to be adjacent to each other with a gap. . When a plurality of the nozzles are used, it is preferable that the nozzles are installed at predetermined intervals in a longitudinal direction of a pipe for supplying the aqueous cleaning liquid so that the entire surface of the plate-shaped surface is in contact with the aqueous cleaning liquid.

The aqueous cleaning liquid sprayed from the nozzle is brought into contact with the entire surface of the plate-like material adjacent to each other.
As a method of injecting the aqueous cleaning liquid from the nozzle into the gap between the plate-shaped materials, for example, (A) the nozzle or the aqueous cleaning liquid injected from the nozzle is so contacted with the entire surface of the plate-shaped surface adjacent to each other that How to move the object to be cleaned,
(B) A method in which a plurality of nozzles are used to spray the aqueous cleaning liquid from the nozzles so that the aqueous cleaning liquid contacts the entire surface of the plate-like surface adjacent to each other, and the like, but the present invention is limited to only such a method. It is not limited.

As a method of moving the nozzle or the object to be cleaned (A), for example, as shown in FIG. 4, a method of moving the object to be cleaned 6 or the nozzle 2 in the vertical direction in the direction of arrow A, or the like. can give. As the method of (B) injecting the aqueous cleaning liquid from the plurality of nozzles using the plurality of nozzles, for example, as shown in FIG. A method of injecting a cleaning liquid to bring the entire surface of the plate-like surface between the plate-like materials constituting the article 6 to be cleaned into contact is provided.

In the present invention, the operation of injecting the aqueous cleaning liquid from the nozzle into the gap between the plate-like materials and then injecting the compressed air from the nozzle into the gap between the plate-like materials is performed at least once. It is preferable in that the cleaning property is improved. Specifically, such an operation can be performed, for example, by injecting an aqueous cleaning liquid from a nozzle into the gap between the plate-shaped materials and then injecting compressed air into the gap between the plate-shaped materials.

The compressed air can be supplied from a high-pressure device such as a high-pressure cylinder or a compressor. Although the pressure of the compressed air is not particularly limited, it is usually 1 kgf / cm ² or more in order to sufficiently increase the cleaning efficiency by sufficiently replacing the aqueous cleaning liquid existing in the gap between the plate-shaped materials. preferably, also as such damage the object to be cleaned is not generated, and to equipment for dealing with high pressure is prevented from upsizing, usually, is preferably 20 kgf / cm ² or less, 10 kgf / cm ² It is more preferred that:

No particular limitation is imposed on the nozzle for injecting compressed air onto the object to be cleaned, and various nozzles can be used. Examples of the ejection pattern ejected from such a nozzle include a fan shape, a filled cone shape, an empty cone shape, a filled pyramid shape, an empty pyramid shape, a direct shape, a fan shape, and the like. There is no particular limitation on the position where the spray nozzle is provided, but it is preferable that the region sprayed from the nozzle is a position where the compressed air sufficiently enters the gap between the plate-like materials constituting the object to be cleaned.

The operation of injecting the aqueous cleaning liquid from the nozzle into the gap between the plate-like materials and then injecting the compressed air from the nozzle into the gap between the plate-like materials can sufficiently achieve the cleaning effect even if performed only once. However, it is preferable to repeat such an operation in order to enhance the cleaning effect. Usually, such an operation is preferably repeated about 2 to 10 times.

In the present invention, after the object to be cleaned is washed, the aqueous cleaning solution present on the surface of the object to be cleaned, and dirt or the like dissolved or dispersed in the aqueous cleaning solution are rinsed off with rinsing water. Is preferred.

As described above, when rinsing is performed, for example, a known method such as a shower method, an immersion method, a rocking method, and a submerged shower method can be employed.

When rinsing is performed, tap water, ion-exchanged water, pure water, or the like can be used as the rinsing water.

Thus, according to the method for cleaning an object to be cleaned according to the present invention, no chlorofluorocarbon or a chlorine-based organic solvent is required for cleaning, and the object to be cleaned in which the plate-like materials are bundled is not disturbed but is kept as it is. In this state, dirt can be efficiently removed from the object to be cleaned.

[0059]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Example 1 In cleaning an object to be cleaned, a cleaning method shown in FIG. 4 was employed.

As an object to be cleaned, a nickel alloy lead frame (95 m
mx 40 mm x 0.1 mm thickness, initial residual oil amount: 24.3 m
g / sheet) (a gap between lead frames: 20 μm) 6 in which 100 sheets were bundled.

Next, a charged conical nozzle (manufactured by Theo Nozzle Co., Ltd., trade name: TK-799, orifice diameter: 5 cm) is opposed to each other so that the shortest distance to the object 6 to be cleaned is 5 cm.
3 mm) 2 were arranged. 10m / from each nozzle 2
While spraying an aqueous cleaning solution (manufactured by Kao Corporation, trade name: Clinthru LC-841, water content: 10% by weight) at 60 ° C. at a spray speed of 2 seconds, the object 6 to be cleaned is arrowed at a speed of 2 cm / min. As shown in A, after the object to be cleaned 6 is washed for 10 minutes while being moved vertically by a distance of 100 mm, the cleaning agent aqueous solution 8 is replaced with city water at 25 ° C., and the same rinsing is performed for 20 minutes. Operation was performed.

Thereafter, the object to be cleaned 6 is dried with hot air at 120 ° C.
For 30 minutes.

Next, as the detergency of the object to be cleaned, the peeling rate and the residual oil amount were examined according to the following methods. The results are shown in Tables 1 and 3.

(Peeling Rate) After the object to be cleaned has been dried,
When it was possible to hold the plate-like materials to be cleaned one by one without applying force, it was determined that "peeled", and the formula: peeling rate (%) = [number of peeled plate-like materials / total plate] Number of shaped materials)
× 100

(Amount of residual oil) After extracting oily dirt remaining on the surface of the object to be cleaned with carbon tetrachloride, an oil content measuring device (H
The amount of residual oil is measured using ORIBA (trade name: OCMA-220).

Comparative Example 1 Ultrasonic cleaner (trade name: UT-20, manufactured by Sharp Corporation)
4) After ethane at 60 ° C. was added as a cleaning liquid, the same object to be cleaned as that used in Example 1 was immersed therein.
Ultrasonic cleaning was performed for 10 minutes. Next, ethane in the ultrasonic cleaner was replaced with ethane at 60 ° C. as a rinsing liquid, and the object to be cleaned was rinsed for 20 minutes, and then dried with hot air at 120 ° C. for 30 minutes. Was.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 1 shows the results.

Comparative Example 2 In Comparative Example 1, an aqueous washing solution (manufactured by Kao Corporation, trade name: Cleanthrough LC-841, water content: 10% by weight) was used instead of ethane, and ethane was used as a rinsing solution instead of ethane. Washing, rinsing and drying were performed in the same manner as in Comparative Example 1 except that city water was used.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 1 shows the results.

[0071]

[Table 1]

From the results shown in Table 1, the method for cleaning an object to be cleaned in Example 1 was performed while moving the lead frame.
Since the operations of washing, rinsing, and drying are performed, it can be seen that a cleaning effect superior to the conventional ultrasonic cleaning method in Comparative Examples 1 and 2 is exhibited.

Example 2 In cleaning an object to be cleaned, the cleaning method shown in FIG. 4 was employed. A substrate (148 mm × 39 mm × 0.4 mm) made of a stamped stainless steel plate was used as an object to be cleaned.
A cleaning object (distance between substrates: 27 μm) 6 in which 100 sheets each having a thickness and an initial residual oil amount: 125 mg / sheet were bundled was used.

A conical nozzle (manufactured by Spraying Systems Japan Co., Ltd., trade name: GG1, orifice diameter: 0.89 mm) such that the shortest distance to the object 6 to be cleaned is 5 cm. 2 were provided.

Each nozzle 2 was sprayed at a jet speed of 25 m / sec.
0 ° C. aqueous cleaning solution (Daiichi Kogyo Seiyaku Co., Ltd., trade name: D
While spraying a 20% by weight aqueous solution of K Beaclear CW-5520, water content: 80% by weight), the object 6 to be cleaned is
After the object to be cleaned 6 was washed for 40 minutes by moving it vertically in a width of 150 mm at a speed of m / 5 minutes, the aqueous washing liquid was replaced with city water, and rinsing was performed for 40 minutes in the same manner as described above. Thereafter, the rinsing operation using the city water was repeated three times.

Next, the object to be cleaned 6 was dried with hot air at 120 ° C. for 40 minutes.

Then, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object 6 to be cleaned. Table 2 shows the results.

Example 3 In cleaning an object to be cleaned, the cleaning method shown in FIG. 5 was employed. The distance to the object 6 to be cleaned is 5 cm.
Four filled conical nozzles (trade name: GG1, orifice diameter: 0.89 mm, manufactured by Spraying Systems Japan KK) 2 were evenly spaced at 5 cm intervals so that

Next, an aqueous cleaning solution at a temperature of 50 ° C. (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name:
W-5520 (20% by weight aqueous solution, water content: 80% by weight) was sprayed onto the object 6 to be cleaned at a spraying speed of 25 m / sec to perform cleaning for 40 minutes. Then, add 5 parts of aqueous washing solution.
Rinse was carried out in the same manner as above except that the water was replaced with city water at 0 ° C. After repeating this rinsing operation three times, hot air drying is performed for 120 minutes.
C. for 40 minutes.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 2 shows the results.

[0081]

[Table 2]

From the results shown in Table 2, it can be seen that both the method of moving the object to be cleaned in Example 2 and the method of injecting the aqueous cleaning liquid from the nozzles using a plurality of nozzles of Example 3 are excellent. It can be seen that the washing effect is exhibited.

Example 4 In Example 1, the charged conical nozzle was changed to a fan-shaped nozzle (trade name: TK-799, manufactured by Theo Nozzle Co., Ltd., orifice diameter: 3 mm) 2, and the aqueous cleaning solution sprayed from the nozzle 2 The cleaning, rinsing, and drying were performed in the same manner as in Example 1 except that the long axis of the spray pattern was disposed so as to be perpendicular to and opposed to the gap between the plate-like materials constituting the object to be cleaned.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

Example 5 In cleaning an object to be cleaned, a cleaning method shown in FIG. 6 was employed. An object to be cleaned (gap between plate-like materials) in which 200 silicon wafers (1 mm thick, initial residual oil amount: 2.4 g / sheet) each having a diameter of 8 inches (about 203.2 mm) sliced by a wire saw are bundled. 250 μm) 6 is suspended by a support 7, and the distance between the plate-like materials constituting the object 6 to be cleaned is set to 5 cm at a distance to the object 6 to be cleaned. ), Trade name: TK-15, orifice diameter: 4 mm) Aqueous cleaning liquid (manufactured by Kao Corporation, trade name: Clinthru K) at an injection speed of 2 to 15 m / sec and 60 ° C
(S-1000, water content: 10% by weight), and the object to be cleaned 6 was washed for 10 minutes while moving the object to be cleaned 6 at a speed of 2 cm / min in the front-rear direction on the paper surface.

Next, city water is sprayed from the nozzle 2 at a spray speed of 15 m / sec into the gap between the plate members constituting the article 6 to be washed, and the article to be washed 6 is rinsed for 10 minutes. After performing the operation twice, hot air drying was performed at 80 ° C. for 30 minutes.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

Example 6 In Example 5, the filled conical nozzle was changed to a fan-shaped nozzle (manufactured by Theo Nozzle Co., Ltd., trade name: TK-799, orifice diameter: 3 mm), and the spray pattern sprayed from the nozzle 2 was changed. The cleaning, rinsing, and drying were performed in the same manner as in Example 5, except that the long axis was disposed so as to be parallel to the gap between the plate-like materials constituting the article 6 to be cleaned.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

Example 7 Cleaning and rinsing were performed under the same conditions as in Example 4 except that the jetting speed of the aqueous cleaning liquid jetted from the nozzle 2 was changed to 2 m / sec, 5 m / sec or 50 m / sec. And drying.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

Example 8 Example 8 was the same as Example 4 except that the long axis of the spray pattern of the nozzle was changed so as to be parallel to the gap between the plate-like materials constituting the object to be cleaned. Under the same conditions, washing,
Rinse and dry.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

Example 9 In Example 5, the cleaning was interrupted midway, and compressed air was injected from the pressurized cylinder at a pressure of 3 kgf / cm ² into the gap between the plate-like members constituting the object 6 to be cleaned for 1 minute. After the operation of injecting the cleaning object 6 into the aqueous cleaning liquid 8 twice,
Washing, rinsing and drying were performed in the same manner as in Example 5.

Next, the peeling rate and the residual oil amount were examined in the same manner as in Example 1 as the cleaning properties of the object to be cleaned. Table 3 shows the results.

[0096]

[Table 3]

As is clear from the results shown in Table 3,
In comparison between Example 1 and Example 4, it can be seen that when the lead frame is used as the object to be cleaned and the nozzle injection pattern is fan-shaped rather than full-cone, the residual oil amount is smaller and the cleaning performance is superior.

The results of Examples 4 and 7 show that the cleaning effect can be improved by increasing the speed at which the aqueous cleaning liquid is sprayed from the nozzle.

Further, from the results of Examples 4 and 8, the cleaning effect is better when the spray pattern of the nozzle and the gap between the plate-like materials constituting the object to be cleaned are vertical than parallel. It can be seen that can be improved.

In the ninth embodiment, the operation of injecting compressed air into the gap between the plate-like members constituting the object to be cleaned during the cleaning is adopted. It can be seen that it has been further improved.

Further, from the result of comparing Example 5 and Example 6, it was found that the silicon wafer was used as an object to be cleaned, and that the aqueous cleaning liquid sprayed from the nozzle was in contact with the entire surface of the plate-like surface between the silicone wafers. It can be seen that, when the cleaning is performed while moving the silicone wafer, the cleaning effect is further improved by changing the spray pattern of the nozzles from a conical shape to a sector shape.

[0102]

According to the method for cleaning an object to be cleaned according to the present invention,
When cleaning, no chlorofluorocarbon or chlorinated organic solvent is required, and it is possible to efficiently remove dirt from the object to be cleaned, without leaving the object to be cleaned in which the plate-shaped material is bundled, without dispersing the object. Is played.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing one embodiment of a nozzle ejection pattern used in the present invention.

FIG. 2 is a schematic explanatory view showing one embodiment of an ejection state when an aqueous cleaning liquid is ejected from a nozzle used in the present invention.

FIG. 3 is a schematic explanatory view showing one embodiment of an ejection state when an aqueous cleaning liquid is ejected from a nozzle used in the present invention.

FIG. 4 is a schematic explanatory view showing one embodiment of the cleaning method of the present invention.

FIG. 5 is a schematic explanatory view showing one embodiment of the cleaning method of the present invention.

FIG. 6 is a schematic explanatory view showing one embodiment of the cleaning method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Injection pattern 2 Nozzle 3 Plate-like material 4 Plate-like material 5 Dirt 6 Object to be cleaned 7 Support

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-6-89889 (JP, A) JP-A-5-47733 (JP, A) JP-A-4-151830 (JP, A) JP-A-7-107 JP-A-7-297162 (JP, A) JP-A-5-291222 (JP, A) JP-A-3-16685 (JP, A) JP-A-2-169075 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B08B 3/00-3/14 H01L 21/304

Claims (7)

(57) [Claims] 1. The gap between plate-like materials is 10 to 500 μm.
So as to hold the object to be cleaned plate-shaped member of a plurality of plate-shaped surface provided with a clearance is disposed such that adjacent to each other are bundled in the gas <br/> in the injection pattern is fan-shaped as a nozzle Is
With nozzle, aqueous wash that will be injected from the nozzle, and wherein each other so as to contact the entire surface of the adjacent plate-like surface, thereby ejecting the aqueous washes in the gap between the plate-like material from the nozzle to be How to wash the washing. Wherein the aqueous cleaning solution from the nozzle Ru is injected so as to contact the entire surface of the plate surfaces adjacent to each other, The method of cleaning according to claim 1 object to be cleaned according to move the nozzle or the object to be cleaned. 3. The method for cleaning an object to be cleaned according to claim 1, wherein the aqueous cleaning liquid is jetted from the plurality of nozzles so that the aqueous cleaning liquid comes into contact with the entire surface of the plate-like surface adjacent to each other. Wherein the long axis of the injection pattern is disposed nozzles so as to be perpendicular with respect to the gap between the plate-like member according to claim 1 to 3
The method for cleaning an object to be cleaned according to any of the above. 5. The method of cleaning according to claim 1-4 to be washed according to any one of the jet velocity from the nozzle when jetting the aqueous wash and 5 m / sec or more. 6. The method of cleaning according to claim 1 to 5 to be washed according to any one plate material is a substrate which is a lead frame or slice. After 7. and the aqueous washes in the gap between the plate-like material is injected from the nozzle, either claims 1-6 for performing one or more times an operation for ejecting compressed air from a nozzle to the gap between the plate-like member The method for cleaning an object to be cleaned according to the above.