Modified PTFE (Polytetrafluoroethylene) resin for preparing semiconductor and preparation method of modified PTFE resin

Abstract

The invention discloses modified PTFE resin for preparing a semiconductor and a preparation method of the modified PTFE resin, and relates to the technical field of semiconductors. The preparation method comprises the following specific steps: adding tetrafluoroethylene into a high-pressure polymerization kettle, starting stirring, sequentially adding a modifier, an emulsifier and a plurality of parts of synergists, raising the temperature and the pressure of the reaction kettle to a specified value, adding an initiator, and initiating a polymerization reaction; and after the reaction is finished, conveying the material polymerized in the polymerization kettle to a mashing barrel through an intermediate tank, carrying out coarse mashing, adjusting the pH value of the material through a washing process, and carrying out fine treatment on the material through an air mill to prepare the PTFE suspension resin powder with different particle sizes. The modified PTFE resin disclosed by the invention has superiority in the aspects of mechanical property, thermal stability, electrical property, chemical stability, low permeability and large-scale production adaptability.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductors, in particular to a modified PTFE resin for preparing semiconductors and a preparation method thereof. Background Art

[0002] At present, the containers of semiconductor etching liquid are mainly made of materials such as ammonium fluoride, plastic and quartz. In the semiconductor manufacturing process, it is used to contain etching agents such as hydrofluoric acid. The etching process occupies a vital position. It involves the precise removal of materials in specific areas on the wafer to form the fine patterns required for integrated circuits. The purity, chemical stability, mechanical strength and cost of the etching container material have a direct impact on the production plan of the etching container.

[0003] The semiconductor industry has extremely high requirements for the purity and performance of materials. Although PTFE suspension resin, as a high-performance material used in semiconductor processing, has many excellent properties, it has the following technical problems in practical application in semiconductor processing:

[0004] 1. High purity requirements: Semiconductors have extremely high requirements for purity. Even trace amounts of particles or chemical contamination may have a serious impact on the quality of semiconductors. Therefore, the high-purity preparation and processing of PTFE suspension resins is a key technical challenge.

[0005] 2. Processing and molding conditions: The processing and molding conditions of semiconductor products are very harsh. PTFE suspension resin needs to maintain high purity during the processing process and also needs to meet specific physical and chemical performance requirements.

[0006] 3. Surface treatment: PTFE parts need to maintain a smooth surface during processing to reduce the risk of material accumulation and contamination of the product. This requires optimization of the surface treatment technology of PTFE suspension resin.

[0007] 4. Low permeability: In order to ensure the purity of the process fluid, the PTFE suspension resin needs to have a low permeability. Pure PTFE material has a large degree of crystallinity and has tiny pores after processing, which can easily cause leakage of the etching solution.

[0008] Based on this, the present invention proposes a modified PTFE resin for preparing semiconductors and a preparation method thereof. Summary of the invention

[0009] The present invention provides a modified PTFE resin for preparing semiconductors and a preparation method thereof, which are used to overcome at least one technical problem in the above-mentioned background technology.

[0010] In order to achieve the above-mentioned invention object, this method proposes the following solution:

[0011] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0012] a. According to the mass fraction, 20000-40000 parts of tetrafluoroethylene are added to the high-pressure polymerization reactor, stirring is started, 50-500 parts of modifier, 50-85 parts of emulsifier and several parts of synergist are added in sequence, after the temperature and pressure of the reactor are raised to the specified value, 2-10 parts of initiator are added to initiate the polymerization reaction;

[0013] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the impurities in the material are washed away by the washing process, and then the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0014] Preferably, the stirring speed in step a is 100-500 rpm.

[0015] Preferably, the modifier in step a is selected from at least one of perfluoropropylene, perfluoromethyl vinyl ether and perfluoropropyl vinyl ether.

[0016] Preferably, the initiator in step a is selected from at least one of ammonium persulfate, sodium persulfate, potassium persulfate, potassium permanganate and potassium bromate.

[0017] Preferably, the reaction conditions in step a are: reaction temperature is 65-75° C.; reaction pressure is 1000-1800 kPa.

[0018] Preferably, the polymerization reaction time in step a is 3-6 hours.

[0019] Preferably, in step b, the material is washed until its conductivity is less than 10 μS / cm.

[0020] Technical effects:

[0021] Compared with traditional methods, this method has the following advantages:

[0022] 1. Enhanced mechanical properties and thermal stability

[0023] Effect of ethers: The introduced ether groups help reduce the crystallinity of the polymer, thereby enhancing the mechanical properties of the material. The introduction of ether segments increases the flexibility of the polymer, helps improve its processability and reduces brittleness, which makes the modified PTFE resin more suitable for use as a packaging material for semiconductor devices.

[0024] 2. Improved electrical properties and chemical stability

[0025] Improvement of overall performance: The addition of these modifiers comprehensively improves the electrical insulation performance and chemical stability of the material, making the modified PTFE resin have better application prospects in semiconductor manufacturing, such as as an insulating layer or anti-corrosion layer.

[0026] 3. The PTFE suspension resin of the present invention has a low permeability, can effectively ensure the purity of the process fluid, and meets the high standard requirements of the semiconductor industry for material purity.

[0027] 4. The preparation method of the present invention is simple and efficient, suitable for large-scale industrial production, and is conducive to reducing production costs and improving production efficiency. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0029] Example 1

[0030] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0031] a. Add 20000g of tetrafluoroethylene to a high-pressure polymerization reactor, start stirring, add 50g of modifier, 50g of emulsifier and synergist in sequence, raise the temperature and pressure of the reactor to the specified value, add 2g of initiator to initiate the polymerization reaction;

[0032] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0033] The stirring speed in step a is 100 rpm.

[0034] In the step a, the modifier is selected from perfluoropropylene.

[0035] In the step a, the initiator is selected from ammonium persulfate.

[0036] The reaction conditions in step a are: reaction temperature is 65° C.; reaction pressure is 1000 kPa.

[0037] The polymerization reaction time in step a is 3 hours.

[0038] In the step b, the material is washed until the electrical conductivity is 6 μS / cm.

[0039] Example 2

[0040] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0041] a. 30000g of tetrafluoroethylene was added to a high-pressure polymerization reactor, stirring was started, 200g of a modifier, 65g of an emulsifier and a synergist were added in sequence, the reactor was heated and pressurized to the specified value, and 5g of an initiator was added to initiate the polymerization reaction;

[0042] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0043] The stirring speed in step a is 200 pm.

[0044] In the step a, the modifier is selected from perfluoromethyl vinyl ether.

[0045] The reaction conditions in step a are: reaction temperature is 70° C.; reaction pressure is 1200 kPa.

[0046] The polymerization reaction time in step a is 4 hours.

[0047] In the step b, the material is washed until the electrical conductivity is 3 μS / cm.

[0048] Example 3

[0049] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0050] a. 30000g of tetrafluoroethylene was added to a high-pressure polymerization reactor, stirring was started, 400g of a modifier, 75g of an emulsifier and a synergist were added in sequence, the reactor was heated and pressurized to the specified value, 8g of an initiator was added, and the polymerization reaction was initiated;

[0051] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0052] The stirring speed in step a is 350 rpm.

[0053] In the step a, the modifier is selected from perfluoropropyl vinyl ether.

[0054] In the step a, the initiator is selected from potassium permanganate.

[0055] The reaction conditions in step a are: reaction temperature is 70° C.; reaction pressure is 1600 kPa.

[0056] The polymerization reaction time in step a is 5 hours.

[0057] In the step b, the material is washed until the electrical conductivity is 4 μS / cm.

[0058] Example 4

[0059] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0060] a. Add 40000g of tetrafluoroethylene to a high-pressure polymerization reactor, start stirring, add 500g of modifier, 85g of emulsifier and synergist in sequence, raise the temperature and pressure of the reactor to the specified value, add 10g of initiator to initiate the polymerization reaction;

[0061] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0062] The stirring speed in step a is 500 rpm.

[0063] In the step a, the modifier is selected from perfluoropropyl vinyl ether.

[0064] In the step a, the emulsifier is selected from potassium perfluorooctane sulfonate.

[0065] The synergist in step a is an organic boron dispersible monomer, and the added amount is 0.3% of the total weight of the monomer. The preparation method thereof is:

[0066] T1: Mix 2-vinyl-5,5-dimethyl-1,3,2-dioxaborane, CAS: 246869-22-7, and polyethylene glycol dithiol in proportion, add triethylamine under stirring, and react at 70°C for 7h under nitrogen protection;

[0067] T2: Dodecafluoro-1,9-decadiene was added, and the mixture was reacted at 70° C. for 3 h under nitrogen protection to obtain an organic boron dispersible monomer.

[0068] The molar ratio of the 2-vinyl-5,5-dimethyl-1,3,2-dioxaborane:polyethylene glycol dithiol:triethylamine:dodecafluoro-1,9-decadiene is 0.05:2:0.06:2.4.

[0069] In the step a, the initiator is selected from potassium bromate.

[0070] The reaction conditions in step a are: reaction temperature is 75° C.; reaction pressure is 1800 kPa.

[0071] The polymerization reaction time in step a is 6 hours.

[0072] In the step b, the material is washed until the electrical conductivity is 6 μS / cm.

[0073] Comparative Example 1

[0074] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0075] a. Add 20000g of tetrafluoroethylene to a high-pressure polymerization reactor, start stirring, add 50g of modifier, 50g of emulsifier, raise the temperature and pressure of the reactor to the specified value, add 2g of initiator, and initiate the polymerization reaction;

[0076] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0077] The stirring speed in step a is 100 rpm.

[0078] In the step a, the modifier is selected from perfluoropropylene.

[0079] In the step a, the emulsifier is selected from ammonium perfluorooctanoate.

[0080] In the step a, the initiator is selected from ammonium persulfate.

[0081] The reaction conditions in step a are: reaction temperature is 65° C.; reaction pressure is 1000 kPa.

[0082] The polymerization reaction time in step a is 3 hours.

[0083] In the step b, the material is washed until the electrical conductivity is 4 μS / cm.

[0084] Comparative Example 2

[0085] A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are as follows:

[0086] a. Add 20000g of tetrafluoroethylene to a high-pressure polymerization reactor, start stirring, add 50g of modifier, 50g of emulsifier and synergist in sequence, raise the temperature and pressure of the reactor to the specified value, add 2g of initiator to initiate the polymerization reaction;

[0087] b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

[0088] The stirring speed in step a is 100 rpm.

[0089] In the step a, the modifier is selected from perfluoropropylene.

[0090] In the step a, the emulsifier is selected from ammonium perfluorooctanoate.

[0091] The synergist in step a is an organic boron dispersible monomer, and the added amount is 0.02% of the total weight of the monomer. The preparation method thereof is:

[0092] 2-vinyl-5,5-dimethyl-1,3,2-dioxaborane (CAS: 246869-22-7) and polyethylene glycol dithiol were mixed in proportion, triethylamine was added under stirring, and the mixture was reacted at 60° C. for 4 hours under nitrogen protection to obtain an organic boron dispersion monomer.

[0093] The molar ratio of the 2-vinyl-5,5-dimethyl-1,3,2-dioxaborane:polyethylene glycol dithiol:triethylamine is 0.02:1:0.03.

[0094] In the step a, the initiator is selected from ammonium persulfate.

[0095] The reaction conditions in step a are: reaction temperature is 65° C.; reaction pressure is 1000 kPa.

[0096] The polymerization reaction time in step a is 3 hours.

[0097] In the step b, the material is washed until the electrical conductivity is 5.5 μS / cm.

[0098] Evaluation of Examples

[0099] 1. Mechanical properties test: tensile strength and elongation at break test: According to ASTM D638 standard, the prepared PTFE suspension resin was subjected to a tensile test using an electronic universal testing machine, and the maximum tensile strength and elongation at break were recorded.

[0100] 2. Thermal stability test: Thermogravimetric analysis (TGA): Use a thermogravimetric analyzer (TGA) to test the sample at a heating rate of 10°C / min in a nitrogen atmosphere and record the thermal gravimetric curve of the sample.

[0101] 3. Electrical performance test: Dielectric constant and dielectric loss factor test: Use an LCR meter to measure the dielectric constant and dielectric loss factor of PTFE suspension resin at different frequencies in accordance with ASTM D150 standard.

[0102] Test results:

[0103]

[0104]

[0105] Through the above tests, the superiority of the modified PTFE resin of the present invention in terms of mechanical properties, thermal stability, electrical properties, chemical stability, low permeability and adaptability to large-scale production can be fully verified, thereby proving its application prospects in the semiconductor field.

[0106] The applicant declares that the present invention is further illustrated by the above embodiments, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A modified PTFE resin for preparing semiconductors and a preparation method thereof, wherein the operation steps are: a. According to the mass fraction, 20000-40000 parts of tetrafluoroethylene are added to the high-pressure polymerization reactor, stirring is started, 50-500 parts of modifier, 50-85 parts of emulsifier and several parts of synergist are added in sequence, after the temperature and pressure of the reactor are raised to the specified value, 2-10 parts of initiator are added to initiate the polymerization reaction; b. After the reaction is completed, the material after polymerization in the polymerization kettle is transported to the crushing barrel through the middle tank for coarse crushing, and then the pH value of the material is adjusted through the washing process. After that, the material is refined by the air mill to prepare PTFE suspension resin powders with different particle sizes.

2. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: The stirring speed in step a is 100-500 rpm.

3. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: In the step a, the modifier is selected from at least one of perfluoropropylene, perfluoromethyl vinyl ether and perfluoropropyl vinyl ether.

4. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: In the step a, the emulsifier is selected from at least one of ammonium perfluorooctanoate or potassium perfluorooctane sulfonate.

5. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: In step a, the initiator is selected from at least one of ammonium persulfate, sodium persulfate, potassium persulfate, potassium permanganate and potassium bromate.

6. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: The reaction conditions in step a are: reaction temperature is 65-75° C.; reaction pressure is 1000-1800 kPa.

7. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: The polymerization reaction time in step a is 3-6 hours.

8. A modified PTFE resin for preparing semiconductors and a preparation method thereof according to claim 1, characterized in that: In the step b, the material is washed until the conductivity is less than 10 μS / cm.

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