A general-purpose plasma cutting protection liquid for coating process, a preparation method and application thereof

Abstract

The application provides a coating process universal plasma cutting protection liquid, a preparation method and application thereof. The coating process universal plasma cutting protection liquid comprises the following components in a weight ratio: 5-20 parts of hyperbranched polyester; 1-3 parts of aromatic carbonyl compound; 20-30 parts of organic solvent; 2-4 parts of film forming aid; and 30-50 parts of ultrapure water. The hyperbranched polyester is a carboxyl-terminated hyperbranched polyester. The application further discloses a preparation method and application of the coating process universal plasma cutting protection liquid. The coating process universal plasma cutting protection liquid can be simultaneously applied to a spin coating process and an ultrasonic spraying process, and a uniform and dense protection film layer can be obtained, so that wafers and structures such as BUMP and grooves on the surface are protected.

Description

Technical Field

[0001] The present invention relates to plasma cutting protection liquid technology, in particular to a universal plasma cutting protection liquid for coating process, a preparation method and application thereof. Background Art

[0002] Plasma dicing is a processing technology that uses dry etching under vacuum to chip (single) wafers. This technology enables high-speed, high-aspect-ratio, and narrow-slice chip formation. In fields such as artificial intelligence, discrete components, and RFID, the industry is gradually moving toward narrow-slice technology to increase the number of chips per wafer. Overall, the advantages of plasma dicing are becoming increasingly prominent. Compared to traditional laser dicing, plasma dicing offers advantages such as high productivity, diverse processing shapes, high cleanliness, and enhanced chip strength.

[0003] The application of plasma cutting technology places higher demands on the film-forming performance and coverage of plasma cutting protection fluids. Currently, plasma cutting protection fluids on the market are only suitable for traditional spin coating processes. However, when faced with specialized conditions such as high bumps (bumps) or deep trenches on the wafer surface, traditional spin coating processes are unable to effectively protect these high bumps / trench structures due to the limited flow characteristics of the liquid. In contrast, ultrasonic spray coating uses ultrasonic energy to atomize liquid into tiny droplets and evenly sprays them onto the wafer surface. This creates a uniform and dense film layer, effectively protecting high bumps / trench structures. Currently, plasma cutting protection fluids are primarily designed for traditional spin coating processes and generally have high solids content and high viscosity. However, ultrasonic spray coating requires low viscosity, low solids content, and good film formation. This difference in compatibility makes existing plasma cutting protection fluids incompatible with ultrasonic spray coating processes, creating a contradiction in the application of this technology.

[0004] To address this technical bottleneck, it is urgent to develop a plasma cutting protection liquid that can be used for both spin coating and ultrasonic spray coating processes, which can effectively protect the wafer and surface graphic structures under different process conditions. Summary of the Invention

[0005] The purpose of the present invention is to address the problem that the current plasma cutting protection liquid is not suitable for the ultrasonic spray process, and to propose a plasma cutting protection liquid that is universal for the coating process. The plasma cutting protection liquid can be applied to both the spin coating process and the ultrasonic spray process, and can obtain a uniform and dense protective film layer, achieving uniform coverage of the wafer and surface BUMP, groove and other structures, breaking through the technical difficulty of "one liquid for two purposes", and can be widely used in advanced packaging grinding and scratching processes.

[0006] 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.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a universal plasma cutting protection liquid for coating process, comprising the following components in the following weight proportions:

[0008] 5-20 parts of hyperbranched polyester;

[0009] 1-3 parts of aromatic carbonyl compound;

[0010] 20-30 parts of organic solvent;

[0011] 2-4 parts of film-forming aid;

[0012] 30-50 parts of ultrapure water;

[0013] Furthermore, the hyperbranched polyester is a carboxyl-terminated hyperbranched polyester.

[0014] Furthermore, the molecular weight of the hyperbranched polyester is 1-2w.

[0015] Furthermore, the hyperbranched polyester is prepared by the following method:

[0016] S1: Under a nitrogen atmosphere, an organic acid anhydride and a polyol are mixed and reacted at 110-115°C for 1-1.5 hours to obtain compound A;

[0017] S2: Under a nitrogen atmosphere, the polyol polymer and compound A are mixed, a catalyst is added, the temperature is raised to 175-185°C, and the reaction is carried out for 8-10 hours; the mixture is cooled to room temperature, an organic polyacid and a polymerization inhibitor are added, the temperature is raised to 170-180°C, and the reaction is carried out for 0.5-1 hour; and the mixture is cooled to room temperature to prepare a hyperbranched polyester.

[0018] Furthermore, in step S1, the organic acid anhydride is one or more of phthalic anhydride, benzoic anhydride, acetic anhydride, maleic anhydride and succinic anhydride.

[0019] Furthermore, in step S1, the organic acid anhydride is preferably phthalic anhydride.

[0020] Furthermore, in step S1, the polyol is one or more of glycerol, pentaerythritol, 1,2-propylene glycol, ethylene glycol, mannitol and polyoxypropylene glycol.

[0021] Furthermore, in step S1, the polyol is preferably glycerol.

[0022] Furthermore, in step S1, the molar ratio of the organic anhydride to the polyol is 1:1-2:1.

[0023] Furthermore, in step S1, the molar ratio of the organic anhydride to the polyol is preferably 1.5:1.

[0024] Furthermore, in step S2, the polyol polymer is one or more of polyethylene glycol, polyvinyl alcohol, dipropylene glycol, and trimerpropylene glycol.

[0025] Furthermore, in step S2, the polyol polymer is preferably polyethylene glycol.

[0026] Furthermore, in step S2, the molecular weight of the polyethylene glycol is 200-2000.

[0027] Furthermore, in step S2, the molecular weight of the polyvinyl alcohol is 200-2000.

[0028] Furthermore, in step S2, the molecular weight of the dipropylene glycol is 200-2000.

[0029] Furthermore, in step S2, the molecular weight of the trimerglycerol is 200-2000.

[0030] Furthermore, in step S2, the catalyst is one or more of tetrabutyl titanate, triisobutylaluminum, triethylaluminum and diethylaluminum chloride.

[0031] Furthermore, in step S2, the catalyst is preferably tetrabutyl titanate.

[0032] Furthermore, in step S2, the organic polyacid is one or more of terephthalic acid, phthalic acid, glutaric acid, succinic acid and malonic acid.

[0033] Furthermore, in step S2, the organic polyacid is preferably terephthalic acid.

[0034] Furthermore, in step S2, the polymerization inhibitor is one or more of resorcinol, phenol, sodium dimethyldithiocarbamate and n-dodecyl methyl sulfide.

[0035] Furthermore, in step S2, the polymerization inhibitor is preferably resorcinol.

[0036] Furthermore, in step S2, the molar ratio of the polyol polymer, compound A, and organic polyacid is 1-1.5:1.5-2.5:3-4.

[0037] Furthermore, in step S2, the molar ratio of the polyol polymer, compound A, and organic polyacid is preferably 1:2:4.

[0038] Furthermore, in step S2, the amount of the catalyst added is 0.1-0.2 moles.

[0039] Furthermore, in step S2, the amount of the catalyst added is preferably 0.2 moles.

[0040] Furthermore, in step S2, the amount of the polymerization inhibitor added is 0.1-0.2 moles.

[0041] Furthermore, in step S2, the amount of the polymerization inhibitor added is preferably 0.2 mol.

[0042] The hyperbranched polyester of the present invention has excellent water solubility and can have a low viscosity while ensuring molecular weight and film-forming properties, thereby being able to simultaneously meet the differentiated requirements of the spin coating process and the ultrasonic spray coating process. The hyperbranched polyester of the present invention contains a large number of hydroxyl groups, carboxyl groups, ester groups and unsaturated bonds in its molecular structure, has excellent adhesion, and can achieve uniform and effective coverage and protection of the wafer surface, BUMP and groove structure surface. The appropriate introduction of benzene rings into the molecular structure of the hyperbranched polyester of the present invention can further improve the conjugation ability of the molecule, promote π electrons to undergo π→π transitions, thereby reducing the heat-affected zone caused by laser grooving and improving plasma etching resistance.

[0043] For example, the present invention synthesizes a hyperbranched polyester with carboxyl end groups using polyethylene glycol, glycerol, phthalic anhydride, terephthalic acid, and other raw materials. The branched structure of the hyperbranched polyester with carboxyl end groups reduces molecular chain entanglement, resulting in an extremely low viscosity (less than 30 MPa·s) at high solids content, enabling deposition into a film on a wafer through ultrasonic atomization. Furthermore, the numerous hydroxyl and ester groups in the molecular structure of the hyperbranched polyester with carboxyl end groups improve the adhesion between the film layer and the wafer. The appropriate introduction of benzene ring structures into the molecular structure of the hyperbranched polyester with carboxyl end groups can improve the etching resistance of the film layer, ensuring good protection of the wafer surface under plasma etching gas.

[0044] Furthermore, the aromatic carbonyl compound is one or more of 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, phenyl o-hydroxybenzoate and resorcinol monobenzoate.

[0045] Furthermore, the aromatic carbonyl compound is preferably 2,4-dihydroxybenzophenone.

[0046] Furthermore, the organic solvent is one or more of methanol, ethanol, N,N-dimethylformamide, acetonitrile, acetone and propylene glycol methyl ether acetate.

[0047] Furthermore, the organic solvent is preferably one or more of methanol, ethanol, acetone and propylene glycol methyl ether acetate.

[0048] Furthermore, the organic solvent is more preferably propylene glycol methyl ether acetate.

[0049] Furthermore, the film-forming aid is polydimethylsiloxane or polymethylhydrogensiloxane.

[0050] Furthermore, the film-forming aid is preferably polydimethylsiloxane.

[0051] The present invention innovatively introduces a film-forming aid with a leveling effect into the universal plasma cutting protective fluid for coating processes. This film-forming aid significantly improves the fluid's spreading properties during the spin coating process, meeting the requirements of both traditional spin coating and ultrasonic spray coating processes. It enhances the wettability of the protective fluid on the wafer surface, improves the leveling effect of the protective fluid during traditional spin coating, and enables the protective fluid to form a more uniform and dense film during ultrasonic spray coating.

[0052] Another object of the present invention is to disclose a method for preparing a universal plasma cutting protection liquid for coating processes, comprising the following steps:

[0053] Step 1: Weigh each component in its respective amount;

[0054] Step 2: Add ultrapure water and hyperbranched polyester into a container, heat to 40°C-60°C, stir for 2-5 hours, cool to room temperature after the hyperbranched polyester is completely dissolved, then add aromatic carbonyl compound, organic solvent and film-forming aid, stir evenly until transparent, and filter to obtain a universal plasma cutting protective liquid for coating process.

[0055] Furthermore, in step 2, ultrapure water and hyperbranched polyester are added into a container, the temperature is raised to 45° C., and stirred for 3 hours.

[0056] Furthermore, the stirring in step 2 is uniform stirring with a rotation speed of 300-600 rpm.

[0057] Furthermore, the filtration in step 2 uses a filter element with a precision of 0.1 μm.

[0058] Another object of the present invention is to disclose the application of a universal plasma cutting protection fluid for coating processes in the field of plasma cutting. The universal plasma cutting protection fluid for coating processes can achieve uniform coverage of wafers, surface bumps, and grooves, effectively preventing the effects of silicon slag and plasma gas on the wafer, thereby improving cutting yield and productivity.

[0059] Furthermore, the application method of the above-mentioned universal plasma cutting protection liquid for coating process comprises the following steps:

[0060] N1: The universal plasma cutting protection liquid for the coating process is used as the cutting stock liquid, and the universal plasma cutting protection liquid is coated on the wafer by a spin coating process and / or an ultrasonic spraying process to form a protective film;

[0061] N2: Laser grooving of the wafer coated with a protective film, followed by a plasma dicing process;

[0062] N3: The cut wafer is cleaned with ultrapure water to complete the plasma cutting operation.

[0063] Furthermore, in N1, the spin coating process is centrifugal spin coating, the centrifugal spin coating speed is 1000-2000 rpm, and the centrifugal spin coating time is 90-150 s.

[0064] Furthermore, in N1, the spraying operation frequency of the ultrasonic spraying process is 50-80 Hz, the flow rate is 0.5-1.5 mL / min, the distance between the nozzle and the wafer is 50-80 mm, the number of spraying times is 3-6 times, and the temperature is 50-80°C.

[0065] The universal plasma cutting protection liquid for coating process of the present invention, its preparation method and application have the following advantages compared with the prior art:

[0066] 1) The universal plasma cutting protective liquid for the coating process of the present invention uses carboxyl-terminated hyperbranched polyester as the main resin. The hyperbranched polyester itself has good film-forming properties and water solubility. Its molecular weight is regulated (molecular weight is 1-2w), which ensures the film-forming effect under low viscosity and high solid content, and can simultaneously meet the differentiated needs of spin coating and ultrasonic spray coating processes. The molecular structure of the hyperbranched polyester of the present invention contains a large number of hydroxyl groups, carboxyl groups, ester groups and unsaturated bonds, has excellent adhesion, and can achieve uniform and effective coverage of the wafer surface, BUMP and groove structure surface; the hyperbranched polyester molecular structure of the present invention introduces a benzene ring, which can further improve the conjugation ability of the molecule, promote π electrons to undergo π→π transition, reduce the heat-affected zone caused by laser grooving, and improve the plasma etching resistance.

[0067] 2) This universal plasma cutting protective fluid is suitable for both traditional spin coating and ultrasonic spray coating processes. The coating method can be selected based on the wafer type, overcoming the technical difficulty of "one fluid for two purposes." The film layer obtained with this protective fluid provides comprehensive protection for the wafer surface, bump, and groove structures.

[0068] The universal plasma cutting protective liquid for coating process of the present invention has good application prospect and large-scale promotion potential in the field of plasma cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 This is a 100x magnified SEM image of the side of the wafer surface after spin coating using Example 1.

[0070] Figure 2 This is an SEM image of the wafer surface after spray coating using Example 1, magnified 80 times.

[0071] Figure 3 This is the OM image of the wafer surface after laser grooving by spin coating using Example 1.

[0072] Figure 4 This is the OM image of the wafer surface after laser grooving using spray coating according to Example 1.

[0073] Figure 5 This is an 80-fold magnified SEM image of the cross section of the wafer after plasma cutting by spin coating in Example 1.

[0074] Figure 6 This is an 80-fold magnified SEM image of the cross section of the wafer cut after the plasma coating spray coating method of Example 1 was used.

[0075] Figure 7This is an SEM image of the surface of the bump wafer coated by spin coating using Comparative Example 1, where the magnification is 700 times.

[0076] Figure 8 This is an SEM image of the bump wafer surface coated with spray coating using Comparative Example 1, where the magnification is 700 times.

[0077] Figure 9 FITR spectrum of hyperbranched polyester 1. DETAILED DESCRIPTION

[0078] The present invention will be further described below with reference to the following examples. The following description of the technical features 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:

[0079] Unless otherwise stated, the units used in this specification are 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.

[0080] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints A and B.

[0081] In this specification, the numerical range expressed using "above" or "below" means a numerical range including the number.

[0082] In this specification, the use of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0083] 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.

[0084] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 15-25°C.

[0085] In this manual, the reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0086] Examples 1-8

[0087] Examples 1-8 disclose a plasma cutting protection liquid universal for various coating processes, the components and weight ratios of which are shown in Table 1, and the preparation method thereof is as follows:

[0088] Step 1: Weigh each component in its respective amount;

[0089] Step 2: Add ultrapure water and hyperbranched polyester into a container, heat to 45°C, and stir uniformly at 400 rpm for 3 hours. After the hyperbranched polyester is completely dissolved, cool to room temperature, then add aromatic carbonyl compounds, organic solvents, and film-forming aids, and stir until uniform and transparent; finally, filter using a 0.1 μm filter element to obtain a universal plasma cutting protective liquid for coating processes.

[0090] Table 1 Components and ratios of universal plasma cutting protection fluid for coating processes of Examples 1-8

[0091]

[0092] Comparative Examples 1-5

[0093] Comparative Examples 1-5 disclose a variety of 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 1.

[0094] Table 2 Components and ratios of plasma cutting protection fluids of Comparative Examples 1-5

[0095]

[0096] The hyperbranched polyesters 1-8 described in Table 1 and the resins 9-13 described in Table 2 were prepared by the following method:

[0097] S1: Weigh organic anhydride / organic acid and polyol according to the ratio and add them to a container equipped with a mechanical stirrer, a condenser, a thermometer, and a nitrogen inlet and outlet. Heat to 110°C and maintain the temperature for 1.5 hours under a nitrogen flow to obtain compound A1-8. The raw materials and ratios in step S1 are shown in Table 3.

[0098] Table 3 Components and ratios in step S1

[0099]

[0100] S2: Weigh the polyol polymer, compound A and organic polyacid according to the ratio;

[0101] The polyol polymer and compound A were added to a container, and a catalyst was added. The mixture was heated to 180° C. under a nitrogen flow, reacted for 9 hours, and then cooled to room temperature.

[0102] Then, the organic polyacid, polymerization inhibitor, and catalyst were added to the system, the temperature was raised to 175°C, the reaction was continued for 1 hour, and then the mixture was cooled to room temperature. After homogenization, the heating and stirring were stopped to obtain the target product. The raw materials and proportions in step S2 are shown in Table 4.

[0103]

[0104] The universal plasma cutting protection liquids for coating processes of Examples 1-8 and the plasma cutting protection liquids of Comparative Examples 1-5 were tested, respectively. The test methods and test results are as follows:

[0105] Table 5 Performance indicators of plasma cutting protection fluid

[0106]

[0107] Based on Table 5, it can be seen that the plasma cutting protection liquid provided by the embodiment of the present invention has a good coating effect regardless of whether it is used in spin coating or spray coating, the heat affected area is less than 2um, and the etching selectivity is greater than 150:1.

[0108] In comparative example 1, resin 9 was selected as the resin. During the preparation of resin 9, compound A was synthesized using phthalic anhydride and glycerol in a molar ratio of less than 1:1 as raw materials, resulting in a lower etching ratio and an increase in the heat-affected zone.

[0109] Comparative Example 2: Resin 10 was selected as the resin. During the preparation of resin 10, dimethylolpropionic acid and glycerol were used as raw materials to synthesize compound A, resulting in a decrease in etching ratio and an increase in heat-affected zone.

[0110] In Comparative Example 3, resin 11 was selected as the resin. During the preparation of resin 11, citric acid was used instead of compound A, which resulted in failure to synthesize the resin, a decrease in the etching ratio, and an increase in the heat-affected zone.

[0111] In comparative example 4, resin 12 was selected as the resin. During the preparation of resin 12, polyethylene glycol was not added, resulting in a decrease in the etching ratio and an increase in the heat-affected zone.

[0112] In comparative example 5, resin 13 was selected as the resin. During the preparation of resin 13, compound A was not added, resulting in a decrease in the etching ratio and an increase in the heat-affected zone.

[0113] Application Example 1

[0114] The above-mentioned Examples 1-8 disclose a method for applying a plasma cutting protection liquid universal for various coating processes in a plasma cutting process, comprising the following steps:

[0115] N1: A general plasma cutting protection liquid is applied to the wafer to form a protective film by a spin coating process; the spin coating process is centrifugal spin coating, the centrifugal spin coating speed is 1000-2000 rpm, and the centrifugal spin coating time is 90-150 s;

[0116] N2: Laser grooving of the wafer coated with a protective film, followed by a plasma dicing process;

[0117] N3: The cut wafer is cleaned with ultrapure water to complete the plasma cutting operation.

[0118] Application Example 2

[0119] The above-mentioned Examples 1-8 disclose a method for applying a plasma cutting protection liquid universal for various coating processes in a plasma cutting process, comprising the following steps:

[0120] N1: A general-purpose plasma cutting protective liquid is applied to the wafer to form a protective film using an ultrasonic spraying process; the ultrasonic spraying process has a spraying operation frequency of 50-80 Hz, a flow rate of 0.5-1.5 mL / min, a distance between the nozzle and the wafer of 50-80 mm, 3-6 spraying times, and a temperature of 50-80°C.

[0121] N2: Laser grooving of the wafer coated with a protective film, followed by a plasma dicing process;

[0122] N3: The cut wafer is cleaned with ultrapure water to complete the plasma cutting operation.

[0123] Performance Testing

[0124] Among them, the test method for performance 1 coating effect is:

[0125] The protective liquid was applied to the wafer surface by spin coating or ultrasonic spray coating, and the degree of film protection was observed by SEM. If there were no missing coating, bubbles, particles, or color streaks on the wafer surface, the coating effect was considered good. On the contrary, if any one or more of the above conditions were present, the coating effect was considered poor.

[0126] Spin coating was performed by centrifugal spin coating at a speed of 1000 rpm for 100 s;

[0127] The ultrasonic spraying operation frequency was 50 Hz, the flow rate was 1 mL / min, the distance between the nozzle and the wafer was 70 mm, the number of spraying times was 5 times, and the temperature was 60 °C.

[0128] The test method for performance 2 heat affected zone is:

[0129] After laser grooving the wafer surface, the heat-affected zone was measured using OM.

[0130] The test method for performance 3 etching selectivity is:

[0131] Use dry etching to etch the silicon substrate to a depth of approximately 100-200 μm. Record the film thickness at this point and calculate the difference between the film thickness before and after etching. The etching ratio is the ratio of the actual depth of the silicon substrate etched to the film thickness difference.

[0132] Figure 1 This is a 100x magnified SEM image of the side of the wafer surface after spin coating using Example 1. Figure 2This is an SEM image of the wafer surface after spray coating using Example 1, magnified 80 times. Figure 3 This is the OM image of the wafer surface after laser grooving by spin coating using Example 1. Figure 4 This is the OM image of the wafer surface after laser grooving using spray coating according to Example 1. Figure 5 This is an 80-fold magnified SEM image of the cross section of the wafer after plasma cutting by spin coating in Example 1. Figure 6 This is an 80-fold magnified SEM image of the cross section of the wafer cut after the plasma coating spray coating method of Example 1 was used. Figure 7 This is an SEM image of the surface of the bump wafer coated by spin coating using Comparative Example 1, where the magnification is 700 times. Figure 8 This is an SEM image of the bump wafer surface coated with spray coating using Comparative Example 1, where the magnification is 700 times. Figure 9 FITR spectrum of hyperbranched polyester 1.

[0133] from Figure 1 and Figure 2 It can be seen that no matter whether traditional spin coating or ultrasonic spray coating is used, the universal plasma cutting protection liquid of the coating process in Example 1 can obtain a uniform and dense film layer, which has a good coverage effect on the wafer surface and structure.

[0134] from Figure 3 and Figure 4 It can be seen that no matter whether conventional spin coating or ultrasonic spray coating is used, the heat-affected zone of the film layer obtained by the universal plasma cutting protective liquid coating process in Example 1 is less than 2 μm after laser grooving.

[0135] from Figure 5 and Figure 6 It can be seen that no matter whether conventional spin coating or ultrasonic spray coating is used, the etching depth of the universal plasma cutting protection liquid Plasma in the coating process of Example 1 is greater than 140 μm, and the etching selectivity ratio is greater than 150:1.

[0136] from Figure 7 and Figure 8 It can be seen that after spraying, there are particles remaining on the surface of the wafer.

[0137] In conjunction with the above-mentioned drawings, the universal plasma cutting protection liquid for coating process of the present invention has good use effect during application.

[0138] from Figure 9 It can be seen that 2860cm -1 The characteristic peak at 1757 cm is attributed to the stretching vibration of -CH3. -1The characteristic peak at 1669 cm is attributed to the stretching vibration of C=O in -COOH. -1 The characteristic peak at 1240 cm is attributed to the stretching vibration of the C=C double bond. -1 The characteristic peak at 3481 cm is attributed to the stretching vibration of COC. -1 The characteristic peak at is the stretching vibration of -OH, which proves the successful synthesis of hyperbranched polyester 1.

[0139] 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above 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 universal plasma cutting protection liquid for coating process, characterized in that: The composition comprises the following components in the following weight ratios: 5-20 parts of hyperbranched polyester; 1-3 parts of aromatic carbonyl compound; 20-30 parts of organic solvent; 2-4 parts of film-forming aid; 30-50 parts of ultrapure water; The hyperbranched polyester is a carboxyl-terminated hyperbranched polyester; The hyperbranched polyester is prepared by the following method: S1: Under a nitrogen atmosphere, an organic acid anhydride and a polyol are mixed and reacted at 110-115° C. for 1-1.5 hours to obtain a compound A; the molar ratio of the organic acid anhydride to the polyol is 1:1-2:1; S2: Under a nitrogen atmosphere, the polyol polymer and compound A are mixed, a catalyst is added, the temperature is raised to 175-185°C, and the reaction is carried out for 8-10 hours; the mixture is cooled to room temperature, an organic polyacid and a polymerization inhibitor are added, the temperature is raised to 170-180°C, and the reaction is carried out for 0.5-1 hour; and the mixture is cooled to room temperature to prepare a hyperbranched polyester.

2. The universal plasma cutting protection liquid for coating process according to claim 1, characterized in that: The molecular weight of the hyperbranched polyester is 1-2w.

3. The universal plasma cutting protection liquid for coating process according to claim 1, characterized in that: In step S1, the organic acid anhydride is one or more of phthalic anhydride, benzoic anhydride, acetic anhydride, maleic anhydride and succinic anhydride; And / or, in step S1, the polyol is one or more of glycerol, pentaerythritol, 1,2-propylene glycol, ethylene glycol, mannitol and polyoxypropylene glycol.

4. The universal plasma cutting protection liquid for coating process according to claim 1, characterized in that: In step S2, the polyol polymer is one or more of polyethylene glycol, polyvinyl alcohol, dipropylene glycol, and trimeryl glycol; And / or, in step S2, the catalyst is one or more of tetrabutyl titanate, triisobutylaluminum, triethylaluminum and diethylaluminum chloride; and / or, in step S2, the organic polyacid is one or more of terephthalic acid, phthalic acid, glutaric acid, succinic acid and malonic acid; And / or, in step S2, the polymerization inhibitor is one or more of resorcinol, phenol, sodium dimethyldithiocarbamate and n-dodecyl methyl sulfide.

5. The universal plasma cutting protection liquid for coating process according to claim 1, characterized in that: The aromatic carbonyl compound is one or more of 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octyloxybenzophenone, phenyl o-hydroxybenzoate and resorcinol monobenzoate; And / or, the film-forming aid is polydimethylsiloxane or polymethylhydrogensiloxane.

6. A method for preparing a universal plasma cutting protection liquid for coating process according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step 1: Weigh each component in its respective amount; Step 2: Add ultrapure water and hyperbranched polyester into a container, heat to 40°C-60°C, stir for 2-5 hours, cool to room temperature after the hyperbranched polyester is completely dissolved, then add aromatic carbonyl compound, organic solvent and film-forming aid, stir evenly until transparent, and filter to obtain a universal plasma cutting protective liquid for coating process.

7. Use of the universal plasma cutting protection liquid for coating process according to any one of claims 1 to 5 in the field of plasma cutting.

8. The application according to claim 7, characterized in that: The steps include: N1: A general-purpose plasma cutting protection liquid is applied to the wafer to form a protective film using a spin coating process and / or an ultrasonic spray coating process; N2: Laser grooving of the wafer coated with a protective film, followed by a plasma dicing process; N3: The cut wafer is cleaned with ultrapure water to complete the plasma cutting operation.

9. The application according to claim 8, characterized in that: In N1, the spin coating process is centrifugal spin coating, the centrifugal spin coating speed is 1000-2000 rpm, and the centrifugal spin coating time is 90-150 s; And / or, in N1, the spraying operation frequency of the ultrasonic spraying process is 50-80 Hz, the flow rate is 0.5-1.5 mL / min, the distance between the nozzle and the wafer is 50-80 mm, the number of spraying times is 3-6 times, and the temperature is 50-80°C.

Images