JP2009013442A - Method of forming partial alumite on aluminum material surface - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of repairing a partial alumite or alumite base exposed part. <P>SOLUTION: As an all-around treatment method in a partial treatment or a repairing method when the partial alumite or the alumite base exposed part occurs, the repair of the base exposed part and the partial alumite treatment are carried out by treating under a condition of 10 μm to 1.5 cm distance between electrodes, an electrode ratio ( a ratio of area of an anode to cathode) of 1: 0.1-2.0, 0.1-20 V voltage, 0-35 °C electrolysis temperature by a device using a liquid or solidified electrolyte and comprising a power source, a material to be treated and a buffer material and electrodes, if need a cooling system and a masking. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a partial processing method for easily processing a surface of an aluminum material used in a semiconductor manufacturing facility, a machine tool, or the like when it is damaged.

In the fields of semiconductor manufacturing equipment, automobile engines, machine tools, compressors, etc., alumite that is light in weight and generates little contaminants, particularly aluminum materials having an anodized surface film, are often used. In semiconductor manufacturing, fine particles floating in the air are disliked, but parts used in the vacuum equipment part are damaged when the surface part is damaged due to wear, random accidents, etc., and this part is exposed. Corrosion resistance of the product significantly decreases, and if this is not repaired promptly, damage will increase due to product defects due to the occurrence of contaminants. However, if the parts including the substrate exposed portion are large or are difficult to remove from the apparatus, the entire apparatus needs to be replaced, and the apparatus replacement cost or damage due to the stop of the production line is enormous.

Semiconductor parts, machine parts, automobile parts, or assembly parts of these parts have been partially anodized due to comparison with the overall size or design changes, but it is said that alumite will be partially processed. I had no idea. Conductivity may be required for electrical use. In such a case, other than the anodized surface, there was a tendency to perform masking or post-processing cutting.

As a conventional treatment method of this type, no anodization has been found, and a so-called brush plating method is known as a similar partial treatment method in the plating field (Non-patent Document 1). The brush plating method requires the use of liquids containing heavy environmental compounds such as heavy metals and cyan, and it is impossible to form a plating film directly on the aluminum metal surface. Anodized aluminum oxide is a plating method. Then it cannot be formed. Further, the method of using the anode / cathode is also reversed, and no attempt has been made to apply the brush plating method to the method of forming the partial alumite.

As a method of forming a part of alumite on the surface of an aluminum material by a conventional method, an alumite formation desired part is formed on the surface of an aluminum base material by a printing transfer method, etc., and this is entirely covered with a mask and masked, and then anodized. It is known that the metal surface of only the desired part is exposed and alumite treatment is applied to perform the partial treatment. However, the number of processes increases and it is practically impossible to use. Only processing is possible.

Japan Plant Maintenance Association edited and published (1991) "Surface modification and regeneration technology", page 56

An object of the present invention is to provide a method for forming an anodic oxide film partially on the surface of an aluminum material, and particularly for semiconductor devices, parts, machine tools, compressors, etc., made of an aluminum material having an anodic oxide film on the surface. It is an object of the present invention to provide a method for treating a damaged portion on the spot when the surface is partially damaged.

The present invention is a method in which an anodized film (referred to as anodized in the following description) is partially formed on the surface of an aluminum alloy, a site to be treated is set, and portions other than the site are covered by masking. Then, the buffer material containing the electrolyte is brought into contact with the site to be treated, the aluminum substrate at the site to be treated is used as the anode, the cathode insoluble in the electrolyte solution is used as the counter electrode, and the area ratio of the anode to the cathode is 1: 0. 1 to 2.0, the distance between the electrodes is 10 μm to 1.5 cm, the voltage is 0.1 to 20 V, the current density is 0.01 to 2.0 A / dm ² , the electrolysis temperature is 0 to 35 ° C., and the pressure is 2 × 10 ^{−. This} is a partial alumite forming method comprising performing anodizing treatment under conditions of ⁴ to 4 × 10 ² KPa and forming 1 to 50 μm alumite at a site to be treated.

The present invention also provides a method for treating a substrate exposed portion of a substrate partially formed on the surface of an equipment, device or component comprising an aluminum substrate having an anodized surface, and a buffer containing an electrolyte in the substrate exposed portion. The material is brought into contact, the aluminum substrate at the exposed base of the substrate is used as the anode, the cathode insoluble in the electrolyte solution is used as the counter electrode, the area ratio of the anode to the cathode is 1: 0.1 to 2.0, and the distance between the electrodes is Anodizing is performed under conditions of 10 μm to 1.5 cm, voltage of 0.1 to 20 V, current density of 0.01 to 2.0 A / dm ² , and electrolysis temperature of 0 to 35 ° C. to form alumite at the exposed base portion. Is a partial surface treatment method.

The electrolyte is in the form of a solution or suspension. In the case of a solution, an aqueous solution or a non-aqueous electrolyte using various alcohols such as diethylene glycol is used. As the electrolyte substance dissolved in water or alcohol, various known electrolyte substances are used. Preferably, a dilute sulfuric acid type, a phosphoric acid type, or an acid compound type containing two carboxylic acid groups and / or sulfonic acid groups is used. Is good. Particularly preferred are polyvalent carboxylic acids such as oxalic acid and maleic acid, or carboxylic acids having a sulfonic acid group. When the electrolytic substance does not dissolve in water or alcohols, it can be used as a liquid in which a fine solid electrolyte is suspended.

A hard or flexible material is used as a buffer material containing the electrolyte solution and suspension. These buffer materials are preferably those that can hold the electrolyte solution for a certain amount or more and for a certain period of time, and are suitable for the shape of the site to be treated or the exposed portion of the substrate, such as cotton cloth or unemployed cloth such as gauze, synthetic fiber such as polypropylene, etc. Preferred is a flexible material obtained by impregnating a woven fabric, non-woven fabric, sponge, clay, or the like with a hygroscopic polymer gel such as polyacrylate or the like. When the part to be treated or the exposed part of the substrate is flat, there is no need for flexibility, so a certain amount of electrolyte solution is retained by the honeycomb structure, sponge-like structure, porous resin, glass fiber structure, etc. If possible, a hard material may be used. The amount of the electrolyte solution or suspension to be contained or impregnated in the buffer material is sufficient if the solution can be brought into contact with the site to be treated.

When the substrate is exposed due to partial damage to parts, devices, etc. that have an anodized surface, the portion that needs to be processed is often patchy. It is preferable to subject the surface of the part to anodization after exposing the base of the aluminum base material by chemical dissolution treatment or electrochemical treatment such as mechanical polishing. In this case, when the material containing the electrolyte solution is brought into contact with the substrate exposed portion by surrounding the exposed surface of the substrate with rubbery material, clay-like material or other flexible material, the material contains excessive electrolyte solution. However, it is preferable that the electrolyte solution does not flow out to a place other than the damaged portion.

The material of the cathode placed in contact with the buffer material containing the electrolyte solution is a material that is difficult to be corroded or dissolved by the electrolyte solution, for example, a linear or plate-like material such as aluminum, carbon, lead, etc. The area is preferably set to a ratio of 0.1 to 2.0 with respect to the exposed area of the aluminum substrate on the anode side. Further, since the cathode does not change the distance between electrodes (between electrodes) depending on the shape, location, and position, it is allowed to move on the substrate exposed portion without being fixed during processing. The distance between the aluminum base portion serving as the anode and the cathode is preferably 10 μm to 1.5 cm, more preferably 1 mm to 1 cm. Thus, reducing the distance between the electrodes is a great feature of the present invention. By reducing the distance between the electrodes, it is possible to process with a weak voltage and a weak current that are not used under normal anodizing conditions. The distance between the electrodes when the substrate exposed portion has a small area of about several mm ² to several cm ² can be reduced to about 10 μm to 0.5 cm. The voltage at the time of anodizing is about 0.1 to 20 V, particularly about 0.1 to 15 V, and the current density is 0.01 to 2.0 A / dm ² , particularly 0.01 to 1.5 A / dm ² . It is preferable to do. When the distance between the electrodes is as short as 10 μm to 1 cm, there is an advantage that the anodic oxidation treatment can be performed even with a voltage of less than 0.1 to 10 V and a weak voltage and a weak current of a current density of about 0.01 to 0.8 A / dm ² .

The electrolytic treatment temperature at the time of repair is usually 0 to 35 ° C., particularly 10 to 35 ° C., but may be cooled and heated as necessary. The pressure is usually a normal pressure, but there is no problem even if the pressure is 2 × 10 ⁻⁴ to 4 × 10 ² KPa under reduced pressure or increased pressure. In the case of reduced pressure, the time for anodizing is shortened. When the pressure is reduced or increased, the portion to be anodized is covered and the pressure is adjusted appropriately.

The electrolytic treatment time depends on the surface area that requires treatment, but in most cases it can be completed in a short time of about 5 to 40 minutes.

In the anodic oxidation, it is preferable to prevent the direct contact between the anode and the cathode by installing an insulating sheet material having a hole through which the electrolyte can move or pass on the surface of the substrate exposed portion. In the anodic oxidation performed by the processing method of the present invention, the distance between the electrodes may be extremely short, for example, 10 to 100 μm. In such a case, there is a risk that the anode and the cathode are short-circuited and directly contacted. In this case, since alumite may not be sufficiently formed, an insulating cushioning material is used to prevent this short circuit between electrodes. The buffer material is not eroded by the solution in which the electrolyte material is dissolved, and is a porous film-like insulating material having a large number of pores to the extent that the solution passes or more, a permeable resin film, Absorbent polymers, honeycomb sheets and the like are used.

According to the method of the present invention, when anodizing is partially performed on the surface of an aluminum alloy, it is possible to form alumite at a necessary site by a simple method without requiring many complicated steps such as print transfer. I can do it. Also, in the field using aluminum materials, such as semiconductor manufacturing equipment, machine tools, compressors, etc., if the material is partially damaged, without removing or moving the material or parts to repair this part This is an advantageous method for processing in the field.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

Example 1
During the assembling process of the semiconductor device, scratches occurred on the 10 μm portion of the anodized surface film of the A5052 material. The scratches were about 1.5 cm long and 0.3 to 0.5 cm wide, and the substrate was exposed, and the area was about 0.6 cm ² . As a repairing method for the portion 5, partial processing was performed by the apparatus shown in FIG. 1 including the power source 6, the material 1 to be processed, the buffer material 2, and the electrode 3. Cut 100% polypropylene non-woven cloth as cushioning material 2 into 2cm x 5cm, put 1.5mm diameter aluminum wire in the center, roll this to make a cylindrical shape of about 1cm diameter x 2cm length, and make this a negative electrode 3 and a portion other than 10 mm in length was masked to obtain an electrode having an area of about 0.5 cm ² . As the work, the peeled part exposed on the substrate is wiped with acetone, and after drying, 2 wt% ammonium fluoride is moistened with a brush and the peeled part is treated for 20 seconds. Next, a cloth soaked in water was applied to the peeling site, and the wiping and washing steps were repeated 5 times until the smut and the solution were removed. Next, the electrode 3 in which an aluminum wire is inserted into the prepared buffer material is set including the repaired part and the surrounding area as shown in FIG. 1, and 20% sulfuric acid + 3 g / L of aluminum as an electrolytic solution, a liquid temperature of 18 ° C., a liquid volume About 0.5 ml of non-woven cloth was moistened with a measuring pipette. The electrolysis conditions were a distance of 3 mm between the electrodes, an area ratio (electrode ratio) between the anode and the cathode of 1: 0.8, a DC voltage of 6.5 V, a current of 10 mA, a current density of 17 mA / cm ² , a pressure of 1.013 × 10 ² KPa, Electrolytic treatment was performed for 15 minutes under the conditions described above, and room temperature sealing was further performed for 15 minutes. As a result, from the relationship between the original color tone of the A5052 material as the material to be treated and the film, the thickness of the formed alumite film was about 9 to 12 μm, and the film was inconspicuous with the surrounding color.

(Comparative Example 1)
Electrolysis was carried out under the same conditions as in Example 1 except for the non-woven cloth of the buffer material. However, because the distance between the electrodes was short, a short circuit occurred, this part became black and the film thickness became non-uniform, resulting in failure of regeneration. As a solution to this problem, it seems that the workability, simplicity, and accuracy are inferior to those of Example 1 in order to produce an accurate jig.

(Example 2)
An A5052 material alumite having a thickness of 10 μm was exposed to a 1.5 cm length × 0.5 cm width and an area of 0.75 cm ² , and alumite was formed on this portion with the apparatus shown in FIG. As buffer material 2, a high-density polyethylene triangular net (manufactured by Sun Techno Co., Ltd., hereinafter referred to as net) is cut into approximately 2 cm x 5 cm, and is folded in three to make aluminum with a diameter of 1.5 mm between the second and third sheets. A line was inserted, and this was used as a negative electrode 3 to tap a portion other than a length of 10 mm to obtain a cathode having an area of about 0.5 cm ² . Further, the upper surface was covered with a cooling forced gel sheet 4 (manufactured by Kobayashi Pharmaceutical Co., Ltd.) for flexibility. As an actual work, wet the substrate exposed (peeled) part of the object to be treated with an acetone cloth, dry it, wet 1 wt% ammonium fluoride with a brush, and use the cloth under the peeled part for other liquids. It processed so that it might apply 10 times, suppressing so that it might not be. Next, a cloth soaked in water was applied to the peeling site, and the wiping and washing steps were repeated 5 times until the smut and the solution were removed. Next, as shown in FIG. 1, the prepared electrode 3 is set with the apparatus including the repaired part and the periphery, and the suspension electrolyte is 20% sulfuric acid + 3 g / L aluminum + carbon powder (particle size 300 nm) 0.05 wt%. A liquid temperature of 18 ° C. and a liquid volume of about 0.5 ml were wetted on a net with a measuring pipette. Electrolysis conditions were electrode distance 2 mm, electrode ratio 1: 0.8, DC voltage 5 V from power source 6, current 15 mA, current density 20 mA / cm ² , pressure 1.013 × 10 ² KPa electrolysis time 10 minutes, room temperature Sealing was performed for 10 minutes. As a result, an alumite film having a thickness of about 8 to 10 μm was formed from the relationship between the color tone of the A5052 material and the film, and it was not extremely conspicuous with the surrounding color.

(Example 3)
A5052 material oxalate alumite film thickness 10μm of the R plane corner length 1.5 cm × width 0.5 cm, to expose the base material of the area 0.75 cm ^2, using the apparatus shown in FIG. 2 as a method for repairing the portion It was done. As buffer material 2, a high-density polyethylene triangular net (manufactured by Sun Techno Co., Ltd., hereinafter referred to as net) is cut into approximately 2 cm x 5 cm, and is folded in three to make aluminum with a diameter of 1.5 mm between the second and third sheets. A line 3 was inserted, and this was used as a negative electrode, and a part other than 10 mm in length was taped to obtain an electrode having an area of about 0.5 cm ² . Furthermore, the upper surface was covered with a forced cooling gel sheet (manufactured by Kobayashi Pharmaceutical Co., Ltd.) flexibly. As an actual work, wet the exfoliated part of the object to be treated with an acetone cloth, dry it, and wet with 1 wt% ammonium fluoride and dry it with a cloth so that no liquid flows under the exfoliated part. Then, it was processed so that it was applied 10 times. Next, a cloth soaked in water was applied to the peeling site, and the wiping and washing steps were repeated 5 times until the smut and the solution were removed. Next, as shown in FIG. 2, the above-mentioned electrode is set including the repaired part and the periphery, and 3% oxalic acid +3 g / L aluminum, 18 ° C. liquid temperature, and about 0.3 ml liquid volume as an electrolyte Moistened. The electrolysis conditions were a distance of 2 mm between electrodes, a pole ratio of 1: 0.8, a DC voltage of 9 V, a current of 10 mA, a current density of 13 mA / cm ² , an electrolysis time of 20 minutes, and room temperature sealing was performed for 15 minutes. As a result, an oxalic acid alumite film having a thickness of about 8 to 10 μm was formed from the relationship between the color tone of the A5052 material and the film, and it was not extremely conspicuous with the surrounding color.

Example 4
A 6061-thick oxalic acid alumite film having a thickness of 10 μm was exposed to a ceiling surface portion having a length of 1.5 cm × width of 0.5 cm and an area of 0.75 cm ² , and this portion was repaired using the apparatus shown in FIG. . Buffer material 2 made of absorbent polymer and non-woven cloth absorbs 3 ml of oxalic acid + 3 g / L aluminum, 0 ° C., 1 ml as an electrolyte, creates a flexible solid electrolyte, and buffers aluminum electrode rod 3 It put in the material and this electrode + buffer material was made to contact the ceiling surface site | part 5 like FIG. For contact, the electrode part was covered with a forced cooling gel (manufactured by Kobayashi Pharmaceutical Co., Ltd.) excellent in flexibility, placed in a box 6 and fixed with a support 6, and electrolysis was performed. The electrolysis was performed at an interelectrode distance of 5 mm, an electrode ratio of 1: 1, a DC voltage of 8 V, a current of 10 mA, a current density of 13 mA / cm ² , a pressure of 1.013 × 10 ² KPa, and an electrolysis time of 15 minutes. Minutes. As a result, an oxalic acid alumite film having a thickness of about 10 μm was formed from the relationship between the color tone of the A6061 material and the film, and it was not extremely conspicuous with the surrounding color.

(Example 5)
An apparatus shown in FIG. 4 was used as a method for forming a 10 μm alumite film only on the central portion (1 cm × 5 cm, 0.05 dm ² ) of the A5052 base material (5 cm × 15 cm × t8 mm). FIG. 4A is a plan view of the positional relationship between the processing target portion 5 and the masking 8 before processing. Masking covers the same surface other than the site to be treated with tape. As a pretreatment operation, the treated part is wiped with acetone, and after drying, 2 wt% ammonium fluoride is moistened with a brush and the treated part is treated for 20 seconds. Next, a cloth sufficiently soaked in water was applied to the site to be treated, and wiping and washing steps were performed 5 times until the smut and the solution were removed. Next, with the apparatus shown in FIG. 4B, the net was cut into about 7 cm × 7 cm as the buffer material 2 and was folded in four. As an electrode, an aluminum plate 3 of 1.5 cm × 6 cm × t 0.8 mm is placed in the third stage, and the aluminum plate other than this area is masked. Further, an acrylic rectangular wall having a size of 2 cm × 8 cmcm × 1 cm in height is formed around the surface to be treated, and the bottom surface is fixed with a double-sided adhesive tape so that the leached electrolyte does not flow out unless necessary. As an electrolytic solution, 20% sulfuric acid + aluminum 3 g / L, a liquid temperature of 20 ° C., and a liquid volume of about 4 ml were wetted with a buffer material by a measuring pipette. The electrolysis was performed at an electrode distance of 5 mm, an electrode ratio of 1: 0.8, a DC voltage of 6.5 V, a current of 70 mA, a current density of 1.5 A / dm ² , a pressure of 1.013 × 10 ² KPa, and an electrolysis time of 15 minutes. The room temperature sealing was performed for 15 minutes. As a result, a film whose thickness is estimated to be about 10 to 12 μm was formed from the relationship between the color tone of the A5052 material and the film, and it was not particularly noticeable from the surrounding color.

The processing method of the present invention can be used as a simple partial processing and partial correction method, and can be used to regenerate a partially peeled state due to scratches, dents, etc. in the assembly process, saving time and cost.

Equipment diagram when alumite substrate exposed part occurs on a plane Equipment diagram when anodized exposed areas occur at corners Equipment diagram when an anodized base exposed part occurs on the ceiling surface Partial anodized equipment diagram

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anodized material 2 Buffer material 3 Negative electrode 4 Gel for cooling 5 Exposed part or treated part 6 Power supply 7 Press box and support bar 8 Masking 9 Acrylic wall

Claims (6)

A method in which an anodized film (hereinafter referred to as anodized aluminum) is partially formed on the surface of an aluminum alloy, a site to be treated is set, a portion other than the site is covered by masking, and an electrolyte is applied to the site to be treated. The aluminum substrate at the site to be treated as the anode, the cathode insoluble in the electrolyte solution as the counter electrode, the area ratio of the anode to the cathode is 1: 0.1 to 2.0, The distance between electrodes is 10 μm to 1.5 cm, voltage 0.1 to 20 V, current density 0.01 to 2.0 A / dm ² , electrolysis temperature 0 to 35 ° C., pressure 2 × 10 ⁻⁴ to 4 × 10 ² KPa. A partial alumite formation method comprising performing anodization under the conditions of and forming 1 to 50 μm alumite at the site to be treated. A method of treating a base material exposed portion partially formed on the surface of an equipment, device or component made of an aluminum base having anodized aluminum, and contacting the base material exposed portion with a buffer material containing an electrolyte. The exposed aluminum substrate is used as an anode, a cathode insoluble in the electrolyte solution is used as a counter electrode, the area ratio between the anode and the cathode is 1: 0.1 to 2.0, and the distance between the electrodes is 10 μm to 1.5 cm. Anodization is performed under conditions of a voltage of 0.1 to 20 V, a current density of 0.01 to 2.0 A / dm ² , an electrolysis temperature of 0 to 35 ° C., and a pressure of 2 × 10 ⁻⁴ to 4 × 10 ² KPa, and the substrate is exposed. Partial alumite formation method which consists of forming 1-50 micrometers alumite in a site | part. 3. The method according to claim 1, wherein the electrolyte is an aqueous electrolyte, a non-aqueous electrolyte, a solid electrolyte containing an aqueous solution, or a suspension electrolyte. 5. The electrolyte-containing buffer material that is capable of adsorbing an electrolyte solution to a buffer material made of a woven fabric, a non-woven fabric, or a sponge containing an absorbent polymer, and that can cope with the shape of the site to be treated or the substrate exposed site is used. Forming method. The method according to claim 1, wherein the facility, apparatus or component is a semiconductor manufacturing facility or a device or component which is difficult to remove used in the facility. The conditions for anodization were an anode to cathode area ratio of 1: 0.1 to 2.0, a distance between electrodes of 10 μm to 1 cm, a voltage of 0.1 to 15 V, and a current density of 0.01 to 1.5 A / dm. ^2. The forming method according to claim 1, wherein the electrolytic temperature is 10 to 35 ° C. and the pressure is 2 × 10 ⁻⁴ to 4 × 10 ² KPa.