A resin, a plasma cutting protection liquid containing the same, and a preparation method and use thereof

Abstract

The present invention provides a resin, a plasma cutting protection liquid containing the same, and a preparation method and use thereof. The resin of the present invention is prepared by the following method: monomer A, monomer B and monomer C are mixed and stirred in ultrapure water until all materials are dissolved; the monomer A is olefinic acid, the monomer B is a monomer containing a benzene ring and a carboxyl group, and the monomer C is sodium p-styrene sulfonate; an initiator is added while stirring; an inhibitor is added to terminate the reaction to prepare a resin solution; the resin solution is injected into a container for precipitation, and dried to prepare a resin. The present invention also discloses a plasma cutting protection liquid comprising the following components in a weight ratio: 10-30 parts of the resin; 0.5-2 parts of an ultraviolet absorber; and 50-80 parts of deionized water. The resin of the present invention can be used for a plasma cutting protection liquid, improves the flexibility and heat resistance of film formation, and is easy to clean after use.

Description

Technical Field

[0001] The invention relates to a plasma cutting protection liquid technology, in particular to a resin, a plasma cutting protection liquid containing the resin, and a preparation method and application thereof. Background Art

[0002] Wafer refers to the silicon wafer used in the manufacture of silicon semiconductor integrated circuits. Wafer cutting is a key process for integrated circuit packaging. If the reliability of the wafer surface cannot be improved during the cutting process, it will have a great impact on the subsequent process, thereby reducing the chip production yield. Although the current wafer cutting has evolved from the original simple blade cutting to laser cutting and plasma cutting, the heat energy generated when the laser irradiates and cuts along the cutting path of the wafer is easily absorbed by the wafer. After the heat energy is absorbed, it is easy to cause silicon to melt or thermally decompose, generate silicon vapor and condense and deposit on the wafer, causing chips to be generated around the edge of the wafer. With the development of plasma etching technology, it is sometimes necessary to etch at a higher operating temperature (for example, greater than 100°C). In addition, due to the narrowing of the wafer cutting path width, and the high-precision semiconductor cutting device, some thermal effect problems are brought about when using it, such as the cutting path cracking due to heat, fragmentation, thermal decomposition of the protective film, and direct exposure of the wafer. These require the protective film to have relatively high thermal stability.

[0003] The current wafer plasma cutting protection liquid can improve the cutting efficiency and stability of wafers to a certain extent, avoid chips or cracks, and thermal stress problems, but there is a problem that it cannot be applied to plasma cutting environments under higher working temperature conditions. Summary of the invention

[0004] The purpose of the present invention is to solve the problem that the existing wafer plasma cutting protection liquid cannot work at a higher temperature, and to provide a resin that can be used in the plasma cutting protection liquid, improve the flexibility and heat resistance of the film, and is easy to clean after use. The plasma cutting protection liquid containing the resin has very good application prospects and large-scale industrial promotion potential in the field of semiconductor chip plasma cutting.

[0005] It should be noted that, in the present invention, unless otherwise specified, the specific meaning of "including" in relation to composition limitations and descriptions includes both open-ended "including", "comprising", etc. and similar meanings, as well as closed-ended "composed of", "composed of", etc. and similar meanings.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a resin is prepared by the following method:

[0007] S1. Mixing monomer A, monomer B and monomer C in ultrapure water and stirring until all materials are completely dissolved; the monomer A is olefinic acid, the monomer B is a monomer containing a benzene ring and a carboxyl group, and the monomer C is sodium p-styrene sulfonate;

[0008] S2, adding initiator while stirring;

[0009] S3, adding a polymerization inhibitor to terminate the reaction and prepare a resin solution;

[0010] S4, injecting the resin solution into a container to precipitate the resin, and drying to obtain the resin.

[0011] Furthermore, the mass ratio of each component in the preparation method is:

[0012]

[0013] Furthermore, the monomer A is one or more of 2-(allyloxy)acetic acid, 2-(allyloxy)-2-oxoacetic acid and ethyl hydrogen fumarate.

[0014] The structural formula of 2-(allyloxy)acetic acid is shown in Formula 1:

[0015]

[0016] The structural formula of 2-(allyloxy)-2-oxoacetic acid is shown in Formula 2:

[0017]

[0018]

[0019] The structural formula of ethyl hydrogen fumarate is shown in Formula 3:

[0020]

[0021] Furthermore, the monomer A is 6-9 parts.

[0022] Further, the monomer B is one or more of 4-(2-acryloxyethyl-1-oxy)-benzoic acid, 4-[(4-vinylphenyl)methoxy]benzoic acid and 4-(5-hexene-1-oxy)benzoic acid. The structure of the monomer B selected in the present invention contains benzoic acid, the carboxyl group has oxygen at the para position, and the carbon chain connected to the oxygen or the terminal position of the benzene ring chain is a carbon-carbon double bond. The addition of the monomer B can improve the water solubility of the resin and the flexibility of the resin film.

[0023] The structural formula of 4-(2-acryloxyethyl-1-oxy)-benzoic acid is shown in Formula 4:

[0024]

[0025] The structural formula of 4-[(4-vinylphenyl)methoxy]benzoic acid is shown in Formula 5:

[0026]

[0027] The structural formula of 4-(5-hexene-1-oxy)benzoic acid is shown in Formula VI:

[0028]

[0029]

[0030] Furthermore, the monomer B is 9-15 parts.

[0031] Furthermore, the monomer C is 14-20 parts.

[0032] The structural formula of sodium p-styrene sulfonate is shown in Formula VII:

[0033]

[0034] The monomer C is sodium p-styrene sulfonate containing a highly thermally stable aromatic ring structure and a strongly hydrophilic sulfonic acid group, which effectively improves the thermal stability of the resin and further improves its water solubility.

[0035] Furthermore, the initiator is one or more of sodium persulfate, dibenzoyl peroxide, and di-tert-butyl peroxide.

[0036] Furthermore, the initiator is 0.003-0.005 parts.

[0037] Furthermore, the polymerization inhibitor is one or more of dibutyl phthalate, diisobutyl phthalate, di(2-ethylhexyl) phthalate, phenol, resorcinol, hydroquinone, p-nitrophenol, ethyl dimercaptopropionate and ethyl 3-mercaptobutyrate.

[0038] Furthermore, the polymerization inhibitor is 0.001-0.002 parts.

[0039] Furthermore, the ultrapure water is deionized water with a resistance exceeding 18 megohms.

[0040] Furthermore, the solid content of the mixed solution in S1 is 15-30wt%.

[0041] Furthermore, the solid content of the mixed solution in S1 is preferably 15-25 wt %.

[0042] Furthermore, in S1, the system is heated to 60-80° C., which helps dissolve the sodium styrene sulfonate.

[0043] Further, in S1, the system is heated to 65-75°C.

[0044] Furthermore, the stirring speed in S1 is 400-800 r / min.

[0045] Furthermore, the reaction temperature in S2 is 60-68°C, and the reaction time is 2-8h.

[0046] Furthermore, the reaction temperature in S2 is preferably 62-66° C., and the reaction time is preferably 3-6 h.

[0047] Furthermore, the drying in S4 is carried out in a vacuum oven.

[0048] Furthermore, in S4, the drying temperature is 80-100° C., and the drying time is 4-8 hours.

[0049] Another object of the present invention is to disclose a use of the resin in the field of plasma cutting protection liquid.

[0050] Another object of the present invention is to disclose a plasma cutting protection liquid, comprising the following components in weight proportion:

[0051] 10-30 parts of the resin;

[0052] 0.5-2 parts of UV absorber;

[0053] 50-80 parts of deionized water.

[0054] Furthermore, the resin is 10-20 parts.

[0055] The plasma cutting protection liquid containing the resin has the advantages of high etching ratio, high thermal stability and easy cleaning. Its high etching ratio can effectively improve the yield rate of cut chips, and the easy cleaning feature can effectively reduce the residue on the chip surface, shorten the cleaning time, and further improve the chip yield and production efficiency.

[0056] Furthermore, the ultraviolet absorber is one or more of ferulic acid, 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine, benzotriazole and benzophenone.

[0057] Furthermore, the ultraviolet absorber is 1-1.5 parts.

[0058] Furthermore, the deionized water is 65-80 parts.

[0059] Another object of the present invention is to disclose a method for preparing a plasma cutting protection liquid, comprising the following steps:

[0060] The resin is added into a container, and then deionized water is added into the container, and stirred at 50-70° C. for 1-4 hours. Finally, an ultraviolet absorber is added and stirred for 2-4 hours to prepare a plasma cutting protection liquid.

[0061] Another object of the present invention is to disclose a use of a plasma cutting protection liquid in the field of semiconductor chip cutting.

[0062] Furthermore, it is particularly suitable for wafer cutting at a cutting temperature greater than or equal to 100°C.

[0063] Furthermore, it is more suitable for wafer cutting with a cutting temperature greater than or equal to 100° C.-150° C.

[0064] Furthermore, the semiconductor chip is cut using the plasma cutting protection liquid, comprising the following steps:

[0065] Step 1: Put plasma cutting protection liquid in a container, place the silicon wafer in a spin coater, and spin coat until it is smooth and defect-free.

[0066] Step 2: Take out the spin-coated silicon wafer and perform the cutting process;

[0067] Step 3: Soak the cut chip in distilled water, take out the chip, rinse it with distilled water, and dry it.

[0068] Furthermore, in step 3, the cut chips are immersed in 50-100° C. distilled water for 2-4 hours.

[0069] Furthermore, in step 3, rinse once with distilled water.

[0070] Furthermore, the drying temperature in step 3 is 90-110° C., and the drying time is 1-3 hours.

[0071] The resin of the present invention, the plasma cutting protection liquid containing the resin, and the preparation method and use thereof have the following advantages compared with the prior art:

[0072] 1) The present invention adopts a ternary copolymerization method to prepare the resin used in the plasma cutting protection liquid. The resin has excellent performance. Under the synergistic effect of three monomers with high thermal stability and hydrophilicity, the resin has high high temperature resistance and easy cleaning performance.

[0073] 2) The monomer used in the present invention contains groups such as hydroxyl and sulfonic acid groups, which greatly improves its hydrophilicity and increases the solubility of the resin in water, making it extremely easy to clean; and the monomer contains an aromatic ring structure, and the thermal stability of the aromatic ring structure is significantly higher than that of aromatic hydrocarbons, so the high temperature resistance of the prepared resin is greatly improved.

[0074] 3) The plasma cutting protection liquid of the present invention has no corrosion to the chip, and has no special requirements for the subsequent cleaning process of the residual protection liquid. Only under the immersion process, the resin protection layer coated on the chip, the debris generated by cutting, the small molecular attachments generated by the pyrolysis of the resin, etc. can be completely washed off, and only pure water washing is required afterwards, and no dirt remains after washing.

[0075] Therefore, the resin of the present invention and the plasma cutting protection liquid containing the resin have very good application prospects and large-scale industrial promotion potential in the field of semiconductor chip plasma cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 is the infrared image of the resin in Example 1;

[0077] Figure 2 Thermogravimetric diagrams of Example 4 and Comparative Example 3;

[0078] Figure 3 The microscope pictures before and after cleaning of Comparative Example 3 are shown on the left, before cleaning, and after cleaning on the right, with a magnification of 40 times;

[0079] Figure 4 The microscope pictures before and after cleaning using Example 4 are shown, with the left side showing before cleaning and the right side showing after cleaning, with a magnification of 40 times. DETAILED DESCRIPTION

[0080] The present invention is further described below with reference to the examples. The description of the technical features described below is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:

[0081] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values ​​and numerical ranges appearing in the present invention should be understood to include the inevitable systematic errors in industrial production.

[0082] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints numerical values ​​A and B.

[0083] In this specification, the numerical range expressed using "above" or "below" means a numerical range including the number.

[0084] In this specification, the word "may" includes both performing a certain process and not performing a certain process.

[0085] In this specification, the use of "optional" or "optional" indicates that certain substances, components, execution steps, application conditions and other factors are used or not used.

[0086] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 15-25°C.

[0087] In this manual, the reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0088] Example 1

[0089] This embodiment discloses a resin, and its preparation method is as follows:

[0090] S1, 9 parts of monomer A 2-(allyloxy)acetic acid, 9 parts of monomer B 4-(2-acryloxyethyl-1-oxy)-benzoic acid and 14 parts of monomer C sodium p-styrene sulfonate were mixed and stirred in 181.3 parts of ultrapure water at 600 r / min, the solid content of the reaction system was controlled to be 15wt%, and the system temperature was heated to 70°C under stirring until all the materials were dissolved;

[0091] S2, add 0.003 parts of initiator di-tert-butyl peroxide while stirring, maintain the reaction temperature at 65°C and continue the reaction for 3 hours;

[0092] S3, adding 0.002 parts of polymerization inhibitor di(2-ethylhexyl) phthalate to terminate the reaction, and preparing a resin solution;

[0093] S4, injecting the resin solution into a container for precipitation, drying in a vacuum oven at 90°C for 6 hours, and preparing a resin. According to infrared spectrum analysis, all monomers have completed the reaction to generate the corresponding resin.

[0094] from Figure 1 It can be seen that 3000cm -1 ~3500cm -1 The broad absorption peaks in the range are characteristic absorption peaks generated by the hydroxyl group and ether bond in the carboxyl group, 880cm -1 ~950cm -1 The characteristic peak between them is the characteristic absorption peak of ether bond, 1060cm -1 ~1200cm -1 The strong absorption peak corresponds to the sulfonic acid group in sodium styrene sulfonate. At the same time, the infrared spectrum shows that the absorption peak at 1600cm -1 ~1650cm -1 There is no obvious absorption peak in the range, and this interval corresponds to the characteristic absorption area of ​​olefin structure, which means that the product does not contain olefin bonds or its content is very small, that is, all monomers have completed the reaction to generate the corresponding resin.

[0095] Example 2

[0096] This embodiment discloses a resin, and its preparation method is as follows:

[0097] S1, 6 parts of monomer A 2-(allyloxy)acetic acid, 15 parts of monomer B 4-(2-acryloxyethyl-1-oxy)-benzoic acid and 10 parts of monomer C sodium p-styrene sulfonate were mixed and stirred in 93 parts of ultrapure water at 400 r / min, the solid content of the reaction system was controlled to be 25wt%, and the system temperature was heated to 60°C under stirring until all the materials were dissolved;

[0098] S2, adding 0.001 parts of initiator sodium persulfate while stirring, maintaining the reaction temperature at 60°C and continuing the reaction for 8 hours;

[0099] S3, adding 0.001 parts of polymerization inhibitor dibutyl phthalate to terminate the reaction, and preparing a resin solution;

[0100] S4. The resin solution is injected into a container for precipitation, and dried in a vacuum oven at 80° C. for 8 h to prepare a resin.

[0101] Example 3

[0102] This embodiment discloses a resin, and its preparation method is as follows:

[0103] S1, 10 parts of monomer A 2-(allyloxy)acetic acid, 8 parts of monomer B 4-(2-acryloxyethyl-1-oxy)-benzoic acid and 20 parts of monomer C sodium p-styrene sulfonate were mixed and stirred in 88.7 parts of ultrapure water at 800 r / min, the solid content of the reaction system was controlled to be 30wt%, and the system temperature was heated to 80°C under stirring until all the materials were dissolved;

[0104] S2, add 0.005 parts of initiator dibenzoyl peroxide while stirring, maintain the reaction temperature at 68°C and continue the reaction for 2 hours;

[0105] S3, adding 0.0025 parts of inhibitor hydroquinone to terminate the reaction, and preparing a resin solution;

[0106] S4. The resin solution is injected into a container for precipitation, and dried in a vacuum oven at 100° C. for 4 h to obtain a resin.

[0107] Comparative Example 1

[0108] This comparative example discloses a resin, the preparation method of which is the same as that of Example 1, except that: 9 parts of monomer A3,5-dihydroxy-6-heptenoic acid, 9 parts of monomer B4-(2-acryloxyethyl-1-oxy)-benzoic acid, and 14 parts of monomer C sodium p-styrene sulfonate are added to 288 parts of ultrapure water and stirred, and the solid content of the reaction system is controlled to be 10wt%.

[0109] Comparative Example 2

[0110] This comparative example discloses a resin, the preparation method of which is the same as that of Example 1, except that: 6 parts of monomer A3,5-dihydroxy-6-heptenoic acid, 15 parts of monomer B4-(2-acryloxyethyl-1-oxy)-benzoic acid, and 10 parts of monomer C sodium p-styrene sulfonate are added to 57.6 parts of ultrapure water and stirred, and the solid content of the reaction system is controlled to be 35wt%.

[0111] Embodiment 4-9

[0112] Examples 4-9 disclose a variety of plasma cutting protection liquids, the components and weight ratios of which are shown in Table 1. The preparation method is as follows: add the resin into a container, then add deionized water into the container, stir at 60°C for 3 hours, and finally add an ultraviolet absorber and continue stirring for 3 hours to prepare a plasma cutting protection liquid.

[0113] Table 1 Components and weight ratios of plasma cutting protection liquids in Examples 4-9

[0114]

[0115] Comparative Examples 3-4

[0116] Comparative Examples 3-4 disclose two plasma cutting protection liquids, the components and weight ratios of which are shown in Table 2, and the preparation methods thereof are the same as those of Example 4.

[0117] Table 2 Components and weight ratios of plasma cutting protection liquid in comparative example 3-4

[0118]

[0119] The plasma cutting protection liquids of Examples 4-9 and Comparative Examples 3-4 were tested respectively, and the test results are shown in Table 3:

[0120] Table 3 Test data

[0121] Example / Comparative Example Thermal decomposition temperature℃ Is there any residue after cleaning? Example 4 436 No residue Example 5 409 No residue Example 6 422 No residue Example 7 419 No residue Example 8 420 No residue Example 9 415 No residue Comparative Example 3 394 There is a residue Comparative Example 4 381 There is a residue

[0122] Referring to Table 3, the resins selected in Examples 4-9 have a solid content in the range of 15-30wt% during preparation, and the prepared resins have good performance, and can obtain plasma cutting protection liquids that are more resistant to high temperatures, easy to clean, and have no residue. The resins selected in Comparative Examples 3 and 4 have solid contents of 10wt% and 35wt% respectively during preparation. Too low a solid content will result in a low polymerization molecular weight, and after film formation, the number of active end groups of the low molecular weight resin is large, so its thermal stability is also low. Too high a solid content will result in high viscosity, obstructed mass transfer, and poor polymerization, so its performance will be very poor.

[0123] Figure 2It is the thermogravimetric diagram of Example 4 and Comparative Example 3; It can be seen that polymerization at a lower solid content will lead to a lower polymerization molecular weight. After film formation, the number of active end groups of the low molecular weight resin is large, so its thermal stability is also low.

[0124] Figure 3 The microscope pictures before and after cleaning of Comparative Example 3 are shown on the left side, before cleaning, and after cleaning on the right side; Figure 4 These are microscope pictures before and after cleaning using Example 4, where the left side is before cleaning and the right side is after cleaning.

[0125] It can be seen that since the resins prepared in the present invention all introduce a large amount of monomers containing aromatic rings, their thermal stability is greatly improved, and the resins polymerized within the appropriate solid content range have high thermal stability and pyrolysis temperatures exceeding 400° C. At the same time, by comparison, it can be seen that the resins prepared at higher or lower solid contents have low molecular weights and reduced thermal stability because their polymerization is affected by chemical equilibrium shift and mass transfer hindrance.

[0126] Test method:

[0127] Thermal decomposition test method:

[0128] The thermal stability of the sample within the range of 50° C. to 800° C. was tested using a thermogravimetric detector to obtain the 5 wt % thermal weight loss temperature of the sample.

[0129] Cleaning effect test method

[0130] After applying plasma cutting protection liquid to the silicon wafer with a spin coater, use a knife to draw multiple cutting paths for cleaning verification. After cleaning, observe whether the cutting paths are clean under a microscope.

[0131] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A resin, characterized in that Prepared by the following method: S1. Mix and stir monomer A, monomer B and monomer C in ultrapure water until all materials are dissolved; the monomer A is olefinic acid, the monomer B is a monomer containing a benzene ring and a carboxyl group, and the monomer C is sodium p-styrene sulfonate; S2, adding initiator while stirring; S3, adding a polymerization inhibitor to terminate the reaction and prepare a resin solution; S4, injecting the resin solution into a container to precipitate, and drying to obtain a resin.

2. The resin according to claim 1, characterized in that The mass ratio of each component is:

3. The resin according to claim 1 or 2, characterized in that The monomer A is one or more of 2-(allyloxy)acetic acid, 2-(allyloxy)-2-oxoacetic acid and ethyl hydrogen fumarate; and / or, the monomer B is one or more of 4-(2-acryloxyethyl-1-oxy)-benzoic acid, 4-[(4-vinylphenyl)methoxy]benzoic acid and 4-(5-hexene-1-oxy)benzoic acid; And / or, the initiator is one or more of sodium persulfate, dibenzoyl peroxide, and di-tert-butyl peroxide; And / or, the polymerization inhibitor is one or more of dibutyl phthalate, diisobutyl phthalate, di(2-ethylhexyl) phthalate, phenol, resorcinol, hydroquinone, p-nitrophenol, ethyl dimercaptopropionate and ethyl 3-mercaptobutyrate.

4. The resin according to claim 1, characterized in that The solid content of the mixed liquid in S1 is 15-30wt%.

5. The resin according to claim 1, characterized in that: In S1, the system is heated to 60-80°C; and / or, the reaction temperature in S2 is 60-68° C. and the reaction time is 2-8 h; And / or, in S4, the drying temperature is 80-100° C. and the drying time is 4-8 h.

6. Use of the resin according to any one of claims 1 to 5 in the field of plasma cutting protection liquid.

7. A plasma cutting protection liquid, characterized in that: The composition includes the following components in weight ratio: 10-30 parts of the resin according to any one of claims 1-5; 0.5-2 parts of UV absorber; 50-80 parts of deionized water.

8. The plasma cutting protection liquid according to claim 7, characterized in that: The ultraviolet absorber is one or more of ferulic acid, 2,4,6-tris(4-hydroxyphenyl)-1,3,5-triazine, benzotriazole and benzophenone.

9. A method for preparing the plasma cutting protection liquid according to claim 7 or 8, characterized in that: The following steps are involved: The resin is added into a container, and then deionized water is added, and the mixture is stirred at 50-70° C. for 1-4 hours. Finally, an ultraviolet absorber is added and stirred for 2-4 hours to prepare a plasma cutting protection liquid.

10. Use of the plasma cutting protection liquid according to claim 7 or 8 in the field of semiconductor chip cutting.

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