Surface wet cleaning method for high-precision beryllium bronze machined part

Abstract

The invention relates to the technical field of semiconductors, in particular to a surface wet cleaning method for a high-precision beryllium bronze machined part. The beryllium bronze machined part is sequentially subjected to acetone soaking, sulfuric acid, acetic acid and hydrogen peroxide normal-temperature soaking, sodium molybdate and hydrogen peroxide normal-temperature soaking and ultrasonic cleaning, and the problem that organic dirt and metal ions on the surface of the beryllium bronze part are separated out is solved. According to detection of element residues on the surface of the cleaned product, the cleaning method can enable the element residues on the surface of the product to reach the SEMI F57 standard, meanwhile, through particulate matter detection and fluorescence detection, the cleaning effect on organic pollution on the surface of the product is superior to that of an existing cleaning method, a part body is not damaged, and therefore the service life of the part is prolonged. The cleaning method is easy and convenient to operate, low in cost and suitable for application and popularization.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and more specifically, to a surface wet cleaning method for high-precision beryllium bronze machined parts. Background Art

[0002] With the rapid development of the global semiconductor market, the demand for high-quality materials continues to increase. Beryllium bronze has been widely used in semiconductor manufacturing due to its good mechanical properties, high conductivity and corrosion resistance. Whether it is statically loaded or dynamically loaded, beryllium bronze can maintain its stable performance and is not prone to plastic failure or fracture. This makes it an ideal choice for applications that require high strength and durability.

[0003] At present, the mainstream cleaning method for beryllium bronze parts is still mainly hydrochloric acid pickling, chromium passivation or organic coating passivation, which can remove the oxide on the surface of beryllium bronze. However, there is no solution to the pollution of chromium ions to the environment and the organic pollution caused by organic matter in organic coatings during the operation of semiconductor equipment.

[0004] Therefore, developing a new wet cleaning process with high cleaning degree and simple procedure is of great significance to improving the surface cleanliness of beryllium bronze. Summary of the invention

[0005] The purpose of the present invention is to provide a surface wet cleaning method for high-precision beryllium bronze machined parts, which is used to reduce the problems of organic dirt and metal ion precipitation on the surface of beryllium bronze parts.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] A method for wet cleaning the surface of a high-precision beryllium bronze machined part comprises the following steps:

[0008] S1: Place the beryllium bronze machined parts into the first cleaning tank, add acetone, and soak at room temperature for 25-35 minutes;

[0009] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an aqueous solution of sulfuric acid, acetic acid and hydrogen peroxide, and soaking at room temperature for 1-2 minutes;

[0010] S3: placing the beryllium bronze machined parts soaked in step S2 into a third cleaning tank, adding an aqueous solution of sodium molybdate and hydrogen peroxide, and soaking at room temperature for 5-10 minutes;

[0011] S4: placing the beryllium bronze machined parts soaked in step S3 into a pure water tank, and performing ultrasonic cleaning, vacuum drying and dust-free packaging in sequence.

[0012] Optionally, in step S4, the ultrasonic frequency is 5-10 W / in 2 , the ultrasonic time is 15-30min.

[0013] Optionally, in step S4, the overflow rate of pure water in the pure water tank is greater than 250 L / h, the pure water resistance is greater than 2 MΩ, and the pure water temperature is 25-40°C.

[0014] Optionally, the first cleaning tank, the second cleaning tank and the third cleaning tank are all high-purity plastic tanks for clean rooms, and the material is PP.

[0015] Optionally, in step S1, the acetone used is high-purity acetone, and its grade is any one of G2, G3, G4 or G5.

[0016] Optionally, in step S2, the aqueous solution of sulfuric acid, acetic acid and hydrogen peroxide consists of sulfuric acid, acetic acid, hydrogen peroxide and water in a volume ratio of 4-5:10-11:5-6:100, preferably one or more of a volume ratio of 5:10:6:100, 4:11:6:100, 5:11:5:100.

[0017] Optionally, in step S3, the aqueous solution of sodium molybdate and hydrogen peroxide consists of sodium molybdate, hydrogen peroxide and water in a mass ratio of 5:9:200-250, preferably one or more of a mass ratio of 5:9:200, 5:9:220, 5:9:250.

[0018] Optionally, the mass concentration of sodium molybdate is 5-10wt%.

[0019] Optionally, the normal temperature in steps S1, S2 and S3 is 15-25°C.

[0020] In summary, the present application has the following beneficial effects: through the chemical cleaning method, the oxidation discoloration of beryllium bronze parts can be effectively avoided during subsequent use. According to the residual element detection on the surface of the product after cleaning, the cleaning method of the present invention can make the residual element on the surface of the product meet the SEMI F57 standard. At the same time, through particulate matter detection and fluorescence detection, the cleaning effect of the present invention on organic pollution on the surface of the product is better than the existing cleaning method, and the component body is not damaged, thereby improving the service life of the component. The cleaning method of the present invention is simple to operate, low in cost, and suitable for popularization and use. DETAILED DESCRIPTION

[0021] The following embodiments are used to describe the present invention in detail, but the protection scope of the present invention is not limited to the following embodiments. The raw materials and equipment used in the present invention can be obtained from the market. The experimental methods in the following embodiments that do not specify specific conditions are usually based on conventional conditions or conditions recommended by the manufacturer.

[0022] Example 1

[0023] A method for wet cleaning the surface of a high-precision beryllium bronze machined part comprises the following steps:

[0024] S1: Place the beryllium bronze machined parts into the first cleaning tank, add an appropriate amount of acetone (enough to submerge the beryllium bronze machined parts), and soak them at room temperature for 30 minutes; wherein the acetone is high-purity acetone of grade G2;

[0025] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an appropriate amount of sulfuric acid, acetic acid, hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 2 minutes at room temperature; wherein the sulfuric acid, acetic acid, hydrogen peroxide aqueous solution is composed of a mixture of sulfuric acid, acetic acid, hydrogen peroxide and water in a volume ratio of 5:10:6:100;

[0026] S3: placing the beryllium bronze machined parts soaked in step S2 into a third cleaning tank, adding an appropriate amount of sodium molybdate hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 10 minutes at room temperature; wherein the sodium molybdate hydrogen peroxide aqueous solution is composed of a mixture of sodium molybdate (5wt%), hydrogen peroxide and water in a mass ratio of 5:9:200;

[0027] S4: placing the beryllium bronze machined parts soaked in step S3 into a pure water tank, wherein the overflow of pure water in the pure water tank is greater than 250L / h, the pure water resistance is greater than 2MΩ, and the pure water temperature is room temperature (25-40°C); and ultrasonic cleaning is performed in a Class 100 clean room in sequence, and the ultrasonic frequency is 5-10W / in 2 , ultrasonic time is 15min, and finally vacuum drying and dust-free packaging are carried out.

[0028] Example 2

[0029] A method for wet cleaning the surface of a high-precision beryllium bronze machined part comprises the following steps:

[0030] S1: Place the beryllium bronze machined parts into the first cleaning tank, add an appropriate amount of acetone (enough to submerge the beryllium bronze machined parts), and soak them at room temperature for 30 minutes; wherein the acetone is high-purity acetone of grade G5;

[0031] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an appropriate amount of sulfuric acid, acetic acid, hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 2 minutes at room temperature; wherein the sulfuric acid, acetic acid, hydrogen peroxide aqueous solution is composed of a mixture of sulfuric acid, acetic acid, hydrogen peroxide and water in a volume ratio of 4:11:6:100;

[0032] S3: placing the beryllium bronze machined parts soaked in step S2 into a third cleaning tank, adding an appropriate amount of sodium molybdate hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 10 minutes at room temperature; wherein the sodium molybdate hydrogen peroxide aqueous solution is composed of a mixture of sodium molybdate (10wt%), hydrogen peroxide and water in a mass ratio of 5:9:250;

[0033] S4: placing the beryllium bronze machined parts soaked in step S3 into a pure water tank, wherein the overflow of pure water in the pure water tank is greater than 250L / h, the pure water resistance is greater than 2MΩ, and the pure water temperature is room temperature (25-40°C); and ultrasonic cleaning is performed in a Class 100 clean room in sequence, and the ultrasonic frequency is 5-10W / in 2 , ultrasonic time is 15min, and finally vacuum drying and dust-free packaging are carried out.

[0034] Example 3

[0035] A method for wet cleaning the surface of a high-precision beryllium bronze machined part comprises the following steps:

[0036] S1: Place the beryllium bronze machined parts into the first cleaning tank, add an appropriate amount of acetone (enough to submerge the beryllium bronze machined parts), and soak them at room temperature for 25 minutes; wherein the acetone is high-purity acetone of grade G5;

[0037] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an appropriate amount of sulfuric acid, acetic acid, hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 1 minute at room temperature; wherein the sulfuric acid, acetic acid, hydrogen peroxide aqueous solution is composed of a mixture of sulfuric acid, acetic acid, hydrogen peroxide and water in a volume ratio of 4:11:6:100;

[0038] S3: placing the beryllium bronze machined parts soaked in step S2 into a third cleaning tank, adding an appropriate amount of sodium molybdate hydrogen peroxide aqueous solution (capable of submerging the beryllium bronze machined parts), and soaking for 5 minutes at room temperature; wherein the sodium molybdate hydrogen peroxide aqueous solution is composed of a mixture of sodium molybdate (10wt%), hydrogen peroxide and water in a mass ratio of 5:9:230;

[0039] S4: placing the beryllium bronze machined parts soaked in step S3 into a pure water tank, wherein the overflow of pure water in the pure water tank is greater than 250L / h, the pure water resistance is greater than 2MΩ, and the pure water temperature is room temperature (25-40°C); and ultrasonic cleaning is performed in a Class 100 clean room in sequence, and the ultrasonic frequency is 5-10W / in 2 , ultrasonic time is 15min, and finally vacuum drying and dust-free packaging are carried out.

[0040] Comparative Example 1

[0041] A method for cleaning high-precision beryllium bronze machined parts comprises the following steps:

[0042] S1: Place the beryllium bronze machined parts into the first cleaning tank, add an appropriate amount of 5wt% hydrochloric acid (enough to submerge the beryllium bronze machined parts), and soak for 30 minutes at room temperature;

[0043] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an appropriate amount of chromate passivation solution (enough to submerge the beryllium bronze machined parts), and soaking at room temperature for 2 minutes;

[0044] S3: Put the beryllium bronze machined parts soaked in step S2 into a pure water tank, the overflow of pure water in the pure water tank is greater than 250L / h, the pure water resistance is greater than 2MΩ, and the pure water temperature is room temperature (25-40°C); and perform ultrasonic cleaning in a Class 100 clean room in sequence, with an ultrasonic frequency of 5-10W / in 2 , ultrasonic time is 15min, and finally vacuum drying and dust-free packaging are carried out.

[0045] Comparative Example 2

[0046] A method for cleaning high-precision beryllium bronze machined parts comprises the following steps:

[0047] S1: Place the beryllium bronze machined parts into the first cleaning tank, add an appropriate amount of 5wt% hydrochloric acid (enough to submerge the beryllium bronze machined parts), and soak for 30 minutes at room temperature;

[0048] S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an appropriate amount of passivation solution containing an azole organic compound (capable of submerging the beryllium bronze machined parts), and soaking at room temperature for 2 minutes;

[0049] S3: Put the beryllium bronze machined parts soaked in step S2 into a pure water tank, the overflow of pure water in the pure water tank is greater than 250L / h, the pure water resistance is greater than 2MΩ, and the pure water temperature is room temperature (25-40°C); and perform ultrasonic cleaning in a Class 100 clean room in sequence, with an ultrasonic frequency of 5-10W / in 2 , ultrasonic time is 15min, and finally vacuum drying and dust-free packaging are carried out.

[0050] The beryllium bronze machined parts after cleaning in Examples 1-3 and Comparative Examples 1-2 were subjected to surface element residue detection (inductively coupled plasma-mass spectrometry), particulate matter detection and fluorescence detection. The detection results are shown in Tables 1 to 6.

[0051] Table 1: Surface element residue detection data of Example 1

[0052]

[0053] Table 2: Surface element residue detection data of Example 2

[0054]

[0055]

[0056] Table 3: Surface element residue detection data of Example 3

[0057]

[0058] Table 4: Surface element residue detection data of comparative example 1

[0059]

[0060]

[0061] Table 5: Surface element residue detection data of comparative example 2

[0062]

[0063] Table 6: Particle detection and fluorescence detection data of Examples 1-3 and Comparative Examples 1-2

[0064] Group <![CDATA[Surface particulate matter (number of 0.3μm particles / cm 2 )]]> UV fluorescence number Example 1 0.02 0 Example 2 0 0 Example 3 0.02 0 Comparative Example 1 4.66 3 Comparative Example 2 10.33 11

[0065] As shown in Tables 1 to 6, the chemical cleaning method can effectively prevent the beryllium bronze parts from oxidative discoloration during subsequent use. According to the residual element detection on the product surface after cleaning, the cleaning method of the present invention can make the residual element on the product surface meet the SEMI F57 standard. At the same time, through particulate matter detection and fluorescence detection, the cleaning effect of the present invention on organic pollution on the product surface is better than the existing cleaning method, and the component body is not damaged, thereby improving the service life of the component. The cleaning method of the present invention is simple to operate, low in cost, and suitable for popularization and use.

[0066] The above specific embodiments are merely explanations of the present application and are not limitations of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments without any creative contribution as needed. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A method for wet cleaning the surface of high-precision beryllium bronze machined parts, characterized in that: The following steps are involved: S1: Place the beryllium bronze machined parts into the first cleaning tank, add acetone, and soak at room temperature for 25-35 minutes; S2: placing the beryllium bronze machined parts soaked in step S1 into a second cleaning tank, adding an aqueous solution of sulfuric acid, acetic acid and hydrogen peroxide, and soaking at room temperature for 1-2 minutes; S3: placing the beryllium bronze machined parts soaked in step S2 into a third cleaning tank, adding an aqueous solution of sodium molybdate and hydrogen peroxide, and soaking at room temperature for 5-10 minutes; S4: placing the beryllium bronze machined parts soaked in step S3 into a pure water tank, and performing ultrasonic cleaning, vacuum drying and dust-free packaging in sequence.

2. The surface wet cleaning method according to claim 1, characterized in that: In step S4, the ultrasonic frequency is 5-10W / in 2 , the ultrasonic time is 15-30min.

3. The surface wet cleaning method according to claim 1, characterized in that: In step S4, the overflow rate of pure water in the pure water tank is greater than 250 L / h, the pure water resistance is greater than 2 MΩ, and the pure water temperature is 25-40°C.

4. The surface wet cleaning method according to claim 1, characterized in that: The first cleaning tank, the second cleaning tank and the third cleaning tank are all high-purity plastic tanks for clean rooms, and the material is PP.

5. The surface wet cleaning method according to claim 1, characterized in that: In step S1, the acetone used is high-purity acetone, and its grade is any one of G2, G3, G4 or G5.

6. The surface wet cleaning method according to claim 1, characterized in that: In step S2, the aqueous solution of sulfuric acid, acetic acid and hydrogen peroxide is composed of sulfuric acid, acetic acid, hydrogen peroxide and water in a volume ratio of 4-5:10-11:5-6:100 composition.

7. The surface wet cleaning method according to claim 1, characterized in that: In step S3, the aqueous solution of sodium molybdate and hydrogen peroxide is composed of sodium molybdate, hydrogen peroxide and water in a mass ratio of 5:9:200-250.

8. The surface wet cleaning method according to claim 7, characterized in that: The mass concentration of sodium molybdate is 5-10wt%.

9. The surface wet cleaning method according to claim 7, characterized in that: The normal temperature in steps S1, S2 and S3 is 15-25°C.

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