Chemical nickel plating cleaning method for semiconductor parts

Abstract

The invention discloses a semiconductor part chemical nickel plating cleaning method which comprises the following steps: step 1, degreasing cleaning: putting a part subjected to chemical nickel plating into a neutral degreasing agent tank with the concentration of 40-60g / L, and soaking for 10-30 minutes; 2, acid cleaning is conducted, specifically, the degreased and cleaned part is placed in a groove containing hydrochloric acid with the concentration being 1-10 g / L to be soaked for 2-5 min; 3, neutralization cleaning is conducted, specifically, the part subjected to acid cleaning is placed in an alkali tank with the concentration being 1-10 g / L to be soaked for 2-5 min; and 4, organic solvent cleaning is conducted, specifically, the part subjected to neutralization cleaning is put into a tank containing isopropanol to be soaked for 2-5 minutes. The cleaning method is used for cleaning the semiconductor key parts subjected to chemical nickel plating so as to remove impurities and residues, and the content of zwitterions on the surfaces of the cleaned parts is low.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor equipment production, and in particular to a method for cleaning chemical nickel plating of semiconductor parts. Background Art

[0002] With the continuous development of semiconductor technology, the manufacturing process of key semiconductor components is becoming more and more sophisticated, and the requirements for cleaning quality are becoming higher and higher. Chemical nickel plating is a commonly used process in the manufacture of key semiconductor components, but during the chemical nickel plating process, impurities and residues may be generated on the surface of key semiconductor components, which will affect the performance and reliability of key semiconductor components. Therefore, a new technical solution is urgently needed to solve at least one of the above technical problems. Summary of the invention

[0003] The invention aims to provide a method for cleaning chemical nickel-plated semiconductor parts, which can clean key semiconductor parts after chemical nickel plating to remove impurities and residues, and the anion and cation content on the surface of the parts after cleaning is low.

[0004] In order to achieve the above technical objectives and meet the above technical requirements, the technical solution adopted by the present invention is: a method for cleaning chemical nickel plating of semiconductor parts, characterized in that it includes the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with a neutral degreasing agent with a concentration of 40-60 g / L and soak for 10-30 minutes; Step 2: Acid cleaning: Place the degreased parts into a hydrochloric acid tank with a concentration of 1-10 g / L and soak for 2-5 minutes. Step 3: Neutralization cleaning: Place the acid-cleaned parts into an alkali tank with a concentration of 1-10 g / L and soak for 2-5 minutes; Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with isopropyl alcohol and soak for 2 to 5 minutes.

[0005] As a preferred technical solution, the temperature in the neutral degreasing agent tank in step one is 45°C~55°C, the temperature in the hydrochloric acid tank in step two is 15°C~25°C, the temperature in the alkali tank in step three is 15°C~25°C, and the temperature in the isopropanol tank in step four is 15°C~25°C.

[0006] As a preferred technical solution, the isopropanol tank is electronic grade.

[0007] As a preferred technical solution, the solution in the alkali tank is a NaOH solution.

[0008] As a preferred technical solution, after the parts are neutralized and cleaned in step 4, the PO4 3-Content ≤12010E12molecules / cm 2 .

[0009] The beneficial effects of the present invention are: 1) Use neutral degreasing agent to remove grease on the surface of chemical nickel-plated parts, and use hydrochloric acid to clean the PO4 residue on the surface of parts. 3- , the alkaline solution in the keyway neutralizes the Cl remaining on the surface of the part - Isopropyl alcohol dissolves a variety of organic and non-polar pollutants, including grease, oxides, and some metal residues, and can clean residues on the surface of parts, meeting the processing requirements of key semiconductor components; 2) After the parts are neutralized and cleaned, the PO4 on their surface 3- Comply with IC test standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a flow chart of a cleaning method provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0011] The present invention is further described below in conjunction with the accompanying drawings.

[0012] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "head", "tail", "top", "bottom", "left", "right", "front", "back", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0013] See also Figure 1 One embodiment of the present invention provides a method for cleaning chemical nickel plating of semiconductor parts, comprising the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with a neutral degreasing agent with a concentration of 40-60 g / L, soak for 10-30 minutes, and the temperature in the tank is 45°C-55°C to remove grease on the surface of the chemical nickel plating parts. Specifically, the neutral degreasing agent is a borate series degreasing agent; Step 2: Acid cleaning - Place the degreased parts into a hydrochloric acid tank with a concentration of 1-10 g / L and soak for 2-5 minutes at a temperature of 15°C-25°C to clean the PO4 residue on the surface of the parts. 3- ; Step 3: Neutralization cleaning - Place the acid-cleaned parts into an alkali tank with a concentration of 1-10 g / L. The solution in the alkali tank is NaOH solution. Soak for 2-5 minutes at a temperature of 15°C-25°C to neutralize the Cl remaining on the surface of the parts. - ; Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with electronic grade isopropyl alcohol and soak for 2 to 5 minutes at a temperature of 15°C to 25°C to dissolve a variety of organic and inorganic pollutants, including grease, oxides and some metal residues.

[0014] Chemical nickel plating can deposit a uniform layer of nickel-phosphorus alloy on parts. Sodium hypophosphite acts as a reducing agent in the electroplating bath to participate in the reaction: Ni 2+ + 2H2PO 2- + 2H2O → Ni(OH)2+ 2H3PO3+ H2↑ In acid baths: PO3 3- + O2 + 2H + → PO4 3- + H2O In the process of nickel ion reduction, sodium hypophosphite acts as a reducing agent to provide electrons, reducing nickel ions into nickel atoms and generating phosphates. Semiconductor key components require that the phosphate content on the surface of the parts meet the standards.

[0015] Embodiment 1: A method for cleaning semiconductor parts by chemical nickel plating comprises the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with a borate degreasing agent with a concentration of 40g / L, soak for 10 minutes, and the temperature in the tank is 45°C; Step 2: Acid cleaning: Place the degreased parts into a 1g / L hydrochloric acid tank and soak for 2 minutes at a temperature of 15°C. Step 3: Neutralization cleaning: Place the acid-cleaned parts into an alkali tank filled with 1g / L NaOH solution for 2 minutes at a temperature of 15°C. Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with electronic grade isopropyl alcohol and soak for 2 minutes at a temperature of 15°C.

[0016] Embodiment 2: A method for cleaning semiconductor parts by chemical nickel plating comprises the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with 50g / L borate degreasing agent and soak for 20 minutes at a temperature of 50°C. Step 2: Acid cleaning: Place the degreased parts into a hydrochloric acid tank with a concentration of 1-10 g / L and soak for 3 minutes at a temperature of 20°C. Step 3: Neutralization cleaning: Place the acid-cleaned parts into an alkali tank with a concentration of 1-10 g / L. The solution in the alkali tank is NaOH solution. Soak for 3 minutes at a temperature of 20°C. Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with electronic grade isopropyl alcohol and soak for 3 minutes at a temperature of 20°C.

[0017] Embodiment 3: A method for cleaning semiconductor parts by chemical nickel plating comprises the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with a borate degreasing agent with a concentration of 60g / L, soak for 30 minutes, and the temperature in the tank is 55°C; Step 2: Acid cleaning: Place the degreased parts into a 10g / L hydrochloric acid tank and soak for 5 minutes at a temperature of 25°C. Step 3: Neutralization cleaning: Place the acid-cleaned parts into an alkali tank containing a 10g / L NaOH solution for 5 minutes at a temperature of 25°C. Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with electronic grade isopropyl alcohol and soak for 5 minutes at a temperature of 25°C.

[0018] The parts in Example 1, Example 2 and Example 3 were subjected to IC anion and cation tests, and the test results are as follows: Table 1 ; Table 2 ; Table 3

[0019] As can be seen from Tables 1 to 3, the anion and cation contents on the surface of the parts of Examples 1 to 3 are significantly lower than the national standard. Therefore, the cleaning method of the present invention has an excellent cleaning effect.

[0020] The above embodiments are merely descriptions for the purpose of clearly illustrating the present invention, and are not limitations on the implementation methods. For those skilled in the art, other different forms of changes or modifications may be made based on the above descriptions. It is not necessary and impossible to enumerate all the implementation methods here, and the obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A method for cleaning semiconductor parts by chemical nickel plating, characterized in that , including the following steps: Step 1: Degreasing and cleaning: Place the parts after chemical nickel plating into a tank filled with a neutral degreasing agent with a concentration of 40-60 g / L and soak for 10-30 minutes; Step 2: Acid cleaning: Place the degreased parts into a hydrochloric acid tank with a concentration of 1-10 g / L and soak for 2-5 minutes. Step 3: Neutralization cleaning: Place the acid-cleaned parts into an alkali tank with a concentration of 1-10 g / L and soak for 2-5 minutes; Step 4: Organic solvent cleaning - Place the neutralized and cleaned parts into a tank filled with isopropyl alcohol and soak for 2 to 5 minutes.

2. The semiconductor parts chemical nickel plating cleaning method according to claim 1, characterized in that, The temperature in the neutral degreasing agent tank in step one is between 45°C and 55°C, the temperature in the hydrochloric acid tank in step two is between 15°C and 25°C, the temperature in the alkali tank in step three is between 15°C and 25°C, and the temperature in the isopropanol tank in step four is between 15°C and 25°C.

3. The semiconductor parts chemical nickel plating cleaning method according to claim 1, characterized in that, The isopropanol tank is electronic grade.

4. The semiconductor parts chemical nickel plating cleaning method according to claim 1, characterized in that: The solution in the alkali tank is a NaOH solution.

5. The semiconductor parts chemical nickel plating cleaning method according to claim 1, characterized in that, After the parts are neutralized and cleaned in step 4, the PO4 on their surface 3- Content ≤120 10E12molecules / cm 2 .

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