Wafer cutting protection liquid composition

Abstract

The invention discloses a wafer cutting protection liquid composition, and belongs to the field of wet electronic chemicals. The composition comprises the following components in percentage by mass: 0.1-5% of a wetting agent, 0.1-2% of a penetrating agent, 0.1-2% of a dispersing agent, 0.1-2% of a pH regulator, 0.1-2% of a nonionic Gemini surfactant and the balance of water, wherein the sum of the mass percentages is 100%. The nonionic Gemini surfactant used in the invention has excellent wettability and permeability, can effectively reduce surface tension at low concentration, does not introduce foreign ions, is easy to rinse, has no residue, and can improve the cleaning ability to particles. The composition prepared from the cutting fluid has good cooling and lubricating effects, has no obvious foam, does not corrode metal to damage an electrode, can protect a wafer from being damaged during cutting, prevents fragments and pollution, is low in irritation and environment-friendly, and meets the environment-friendly requirement.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of wet electronic chemicals, and particularly relates to a wafer cutting protection liquid composition used in the process of integrated circuit chip outsourcing and packaging. BACKGROUND

[0002] Wafer cutting (or dicing) is an important step in the semiconductor manufacturing process, which aims to divide the wafer processed by multiple procedures into multiple independent dies. These dies usually contain complete circuit functions and are the core components used to manufacture electronic products. With the increasing complexity of chip design and the reduction of size, the precision and efficiency of wafer cutting technology are also increasingly required. As an important bridge connecting design and manufacturing, the advancement and precision of wafer cutting technology directly affect the performance of the final product. There are many common wafer cutting methods, such as abrasive wheel cutting, laser cutting, diamond blade dicing and splitting, and invisible cutting, etc.

[0003] Mechanical dicing is a method of physically cutting wafers using diamond blades, which is the most traditional and widely used dicing technology. Its main principle is that the diamond blade cuts the wafer at high speed, and the generated heat and debris are carried away by the cutting liquid. The cutting protection liquid helps to reduce the cutting temperature, prevent overheating damage, and has a cooling function. It can also reduce the friction between the cutting blade and the wafer, prolong the life of the tool, and remove the debris generated during cutting to avoid contamination. Finally, it can also protect the wafer metal electrode and cutting equipment from corrosion.

[0004] Patent CN 112708495A discloses a GaAs wafer cutting liquid composed of oligosaccharide compounds, wetting agents, dispersants, chelating agents, solubilizers, bacteriostatic agents and acid-base adjusting agents. The oligosaccharide compounds used can block the direct contact of silicon debris with the wafer surface, preventing silicon debris from contaminating the wafer. However, it can only effectively clean silicon debris and has no protective effect on metal electrodes, and it is easy to corrode metal in the presence of sodium ions. Patent CN 112662460A discloses a wafer cutting liquid containing natural plant extracts, which is more likely to form a protective film by bonding with the electrons on the metal surface, inhibiting the electrochemical corrosion of the pads on the surface of the semiconductor wafer. However, it cannot effectively reduce the cutting temperature and does not have sufficient wettability to reduce the friction between the wafer and the blade, and the lack of wettability results in insufficient cleaning and protection of the wafer and the blade. SUMMARY

[0005] In order to overcome the poor wet cleaning ability of the existing wheel cutting protection liquid, which can cause corrosion of the electrode metal and abnormal electrical signal, the application provides a wafer cutting protection liquid composition, which can greatly reduce the surface tension of the system in the high dilution process by adding a specific non-ionic Gemini surfactant, and has excellent wetting and permeability.

[0006] In order to achieve the above-mentioned purpose, the application adopts the following technical solutions: A wafer cutting protection liquid composition, according to the sum of mass percentages of 100%, the mass percentages of each component in the composition are as follows: wetting agent 0.1-5%, penetrating agent 0.1-2%, dispersing agent 0.1-2%, pH regulator 0.01-5%, non-ionic Gemini surfactant 0.1-2%, and the balance is water.

[0007] Further, the chemical structural formula of the non-ionic Gemini surfactant is as follows: , Wherein, n is an integer of 5-10.

[0008] Further, the preparation of the non-ionic Gemini surfactant comprises the following steps: (1) Synthesis of intermediate I

[0009] Pentanediol and sebacic acid are mixed in a solvent benzene at a molar ratio of 1:2, and 5% of the total molar amount of raw materials is added as a catalyst p-toluenesulfonic acid, and reacted at 140℃ for 6 hours, and then distilled and purified to obtain intermediate I.

[0010] (2) Synthesis of intermediate II

[0011] Triethanolamine and the obtained intermediate I are mixed at a molar ratio of 2:1, and 5% of the total molar amount of raw materials is added as a catalyst p-toluenesulfonic acid, and refluxed for 5 hours, and then distilled and purified to obtain intermediate II.

[0012] (3) Synthesis of non-ionic Gemini surfactant

[0013] Under an inert protective atmosphere, the obtained intermediate II is mixed with potassium hydroxide at a molar ratio of 1:1, and stirred and heated to 70℃, then propylene oxide is added in an amount not less than 4n:1 (n is an integer of 5-10) of the molar ratio of intermediate II, and reacted for 10 hours, and then cooled and purified after reaction to obtain the non-ionic Gemini surfactant.

[0014] Further, the wetting agent is selected from any one or more of fatty alcohol polyoxyethylene ether, octylphenol polyoxyethylene ether, polyoxyethylene polyoxypropylene block copolymer, decyl glucoside, sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, alkyl phosphate ester, alpha-olefin sulfonate, sodium lauroyl methylsarcosinate, cocamidopropyl betaine.

[0015] Further, the penetrating agent is selected from any one or more of polyethylene glycol, sorbitol, mannitol, propylene glycol, secondary alcohol polyoxyethylene ether, sodium dodecylsulfonate, diisooctyl sulfosuccinate, isomeric tridecanol ether phosphate ester.

[0016] Further, the dispersing agent is selected from any one or more of methyl cellulose, carboxymethyl cellulose, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, styrene-maleic anhydride copolymer, vinyl acetate-maleic anhydride copolymer, polyacrylic acid and its salts, polyvinylpyrrolidone, sulfonated polystyrene, oil amino oleate.

[0017] Further, the pH adjusting agent is selected from any one or more of potassium dihydrogen phosphate, disodium hydrogen phosphate, potassium hydroxide, sodium hydroxide, potassium hydrogen phthalate, sodium tetraborate, potassium tetraborate, monoethanolamine, diethanolamine, triethanolamine, diglycolamine, N-butyl diethanolamine, triethylamine.

[0018] Further, the water is high-purity water with a resistivity greater than 18 MΩ / cm.

[0019] Further, the method for preparing the composition is to add the wetting agent, the penetrating agent, the dispersing agent, the non-ionic Gemini surfactant to water, stir at a rotation speed of 200 rpm to form a uniform system, then add the pH adjusting agent, mix uniformly to obtain a uniform, stable, clear and transparent solution.

[0020] The significant advantages of the present application are: The surface active agent used in the present application belongs to non-ionic Gemini surface active agent, has lower critical micelle concentration, lower foaming property and better wetting property, and has oxygen atom, nitrogen atom and lone pair electron in the skeleton, which can promote the horizontal adsorption of the surface active agent molecules on the electrode surface, and in the adsorption process, the surface active agent molecules can cover the larger surface area of the electrode at a relatively low concentration, delay the reaction of the metal electrode and the corrosion medium, and thus protect the metal electrode from corrosion. Meanwhile, the propylene oxide groups in the surface active agent have high polarity, can effectively dissolve the dirt on the wafer surface, and the higher the number of propylene oxide groups, the greater the viscosity and the stronger the adsorption capacity on the metal surface, and it is easier to form a stable lubricating film on the metal surface, so that the friction and heat generation during wafer cutting can be further reduced, and the service life of the equipment can be improved. In addition, the polyether structure can form a stable film on the surface of the foam, hinder the diffusion of gas through the interface into the liquid, effectively inhibit the generation of foam, and promote the rapid rupture of the generated foam, so that the foam disappears quickly, avoiding the deposition of foam in the equipment and pipeline to cause cutting failure or pipeline blockage. In addition, the flexible structure of the polyether chain segment can quickly adsorb to the interface and adjust the orientation, further reduce the surface tension, improve the wetting and penetration ability, effectively disperse the particle debris generated during cutting, and avoid the deposition of particles at the welding point to block the pipeline.

[0021] In summary, the surface active agent used in the present application has more excellent wetting performance and penetration performance, can effectively reduce the surface tension at a low concentration, and will not introduce impurity ions, is easy to rinse, has no residue, and can improve the cleaning ability of particles, so that the composition prepared by using the same has good cooling and lubricating effect, has no obvious foam, will not cause corrosion damage to the metal electrode, can protect the wafer from damage during cutting, and can prevent debris and pollution, and has low irritation, is friendly to the environment, meets the environmental protection requirements. DETAILED DESCRIPTION

[0022] A wafer cutting protection liquid composition is prepared by adding a wetting agent, a penetrating agent, a dispersing agent and a non-ionic Gemini surface active agent into water, stirring to form a uniform system at a rotation speed of 200 rpm, then adding a pH regulator and mixing uniformly to obtain a uniform, stable, clear and transparent solution. According to the total mass percentage of 100%, the mass percentage of each component is as follows: the wetting agent is 0.1-5%, the penetrating agent is 0.1-2%, the dispersing agent is 0.1-2%, the pH regulator is 0.01-5%, the non-ionic Gemini surface active agent is 0.1-2%, and the balance is water.

[0023] The wetting agent is selected from any one or more of fatty alcohol polyoxyethylene ether, octylphenol polyoxyethylene ether, polyoxyethylene polyoxypropylene block copolymer, decyl glucoside, sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, alkyl phosphate ester, alpha-olefin sulfonate, sodium lauroyl methylsarcosinate, cocamidopropyl betaine.

[0024] The penetrating agent is selected from any one or more of polyethylene glycol, sorbitol, mannitol, propylene glycol, secondary alcohol polyoxyethylene ether, sodium dodecylsulfonate, diisooctyl ester sulfonate of maleic acid, isomeric tridecanol ether phosphate ester.

[0025] The dispersing agent is selected from any one or more of methyl cellulose, carboxymethyl cellulose, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, styrene-maleic anhydride copolymer, vinyl acetate-maleic anhydride copolymer, polyacrylic acid and its salts, polyvinylpyrrolidone, sulfonated polystyrene, and oil amino oleic acid ester.

[0026] The pH regulator is selected from any one or more of potassium dihydrogen phosphate, disodium hydrogen phosphate, potassium hydroxide, sodium hydroxide, potassium hydrogen phthalate, sodium tetraborate, potassium tetraborate, monoethanolamine, diethanolamine, triethanolamine, diglycolamine, N-butyl diethanolamine, and triethylamine.

[0027] The water is high-purity water with a resistivity greater than 18 MΩ / cm.

[0028] The chemical structure of the non-ionic Gemini surfactant is as follows: , wherein n is an integer of 5-10.

[0029] In order to make the content of the present application more convenient to understand, the technical solutions of the present application are further described below in combination with specific embodiments, but the present application is not limited thereto.

[0030] Unless otherwise specifically stated, all the various raw materials, reagents, instruments and equipment used in the present application can be purchased from the market or can be prepared by existing methods.

[0031] The preparation method of the non-ionic Gemini surfactant A (n=10) used in the examples is as follows: Step one: synthesis of intermediate I 0.05 mol of pentanediol and 0.1 mol of sebacic acid were added to 50 mL of dry benzene, and 0.0075 mol of catalyst p-toluenesulfonic acid was added, and the mixture was reacted at 140℃ for 6 hours. After the reaction mixture was cooled, distilled water was added, and the organic layer containing the diester was collected by layer separation. After drying overnight, vacuum distillation was performed, and further purification was performed by vacuum fractionation to obtain intermediate I.

[0032] Step two: synthesis of intermediate II 0.1 mol of triethanolamine and 0.05 mol of intermediate I were added to 30 mL of xylene, and 0.0075 mol of p-toluenesulfonic acid was added as a catalyst, and the esterification reaction was refluxed for 5 hours. After the reaction was completed, the product was washed with a 0.5 wt% sodium bicarbonate solution at 40°C to neutralize the catalyst, then the product was extracted with 50 mL of petroleum ether three times, and after removing the solvent by a rotary evaporator, it was completely dried under vacuum at 30°C to obtain intermediate II.

[0033] Step three: synthesis of nonionic Gemini surfactant A 0.01 mol of intermediate II and 112 mL of 0.5 wt% KOH solution were stirred and heated to 70°C, while nitrogen was slowly flowed through the system to remove oxygen. After the oxygen was removed, the nitrogen was stopped, and 0.11 mol of propylene oxide was added dropwise under the condition of continuous stirring and heating, and reacted for 10 hours to obtain nonionic Gemini surfactant A.

[0034] According to FTIR analysis, the obtained surfactant A has a characteristic absorption peak corresponding to -OH at 3464 cm -1 , a characteristic absorption peak corresponding to C-H at 2918 cm -1 , a characteristic absorption peak corresponding to C-O-C at 1088 cm -1 , a characteristic absorption peak of -C=O stretching vibration at 1732 cm -1 , a characteristic absorption peak of CH2 group C-H bond vibration frequency at 1455 cm -1 , and a characteristic absorption peak of C-O group stretching vibration frequency at 1155 cm -1 .

[0035] According to 1 H NMR( δ , DMSO, 300 MHz) analysis, the chemical shift is ( δ ): 4.13 (m, 8H, -CH2-CH2-O); 3.63 (m, 16H, -CH2-CH2-O); 3.40 (m, 4H, CH3-CH-O); 3.13 (m, 8H, -CH2-N-CH2); 2.53 (s, 4H, -OH); 2.32 (m, 8H, -CH2-CH2-C); 1.73 (m, 4H, -CH2-CH3); 1.60 (m, 12H, -CH2-CH2-CH2); 1.32 (m, 12H, CH-CH3); 0.95 (t, 120H, -CH3).

[0036] According to13 C NMR δ , DMSO, 300 MHz) analysis, the chemical shifts are ( δ ): 173.1; 151.8; 80.3; 78.4; 77.8; 75.7; 67.3; 65.2; 52.2; 33.9; 24.7; 21.6; 19.6; 17.6; 10.3.

[0037] According to the HRMS analysis, the molecular formula of the product is C 151 H 298 N2O 52 , m / z: 2973.08.

[0038] The above proves that the Gemini surfactant A with n = 10 is successfully synthesized.

[0039] Meanwhile, the pentanediol and sebacic acid used in step one are replaced by equal amounts of ethanol and acetic acid, and the preparation is carried out in the same way to obtain non-ionic Gemini surfactant B (n = 10) as a comparison, the molecular formula of which is C 68 H 137 NO 24 , and the structural formula is as follows: .

[0040] Examples and comparative examples: The cutting protection liquid compositions of the examples and comparative examples are prepared according to the compositions and mass percentages shown in Table 1.

[0041] Table 1

[0042] Performance measurement In order to evaluate the cutting effect of the cutting protection liquid compositions of Examples 1-6 and Comparative Examples 1-6 on gallium arsenide wafers, relevant tests were carried out by the following tests.

[0043] The test method is as follows: I. Stability test According to different formula configurations, the protection liquid is compared whether the drug system is clear, transparent and uniform O: clear and transparent; X: turbid and precipitated.

[0044] II. Wettability test According to the dilution of 3000 times of the on-line use concentration of the cutting protection liquid, the surface tension is tested, and the wettability of the drug liquid is compared O: surface tension < 50 mN / m; X: surface tension > 50 mN / m.

[0045] III. Cutting performance detection Put 4-inch clean GaAs wafer into the cutting machine for 3 hours, liquid: water = 1:2000 (v / v), normal temperature spraying, after cutting, rinse with two fluids for 5 min, dry with nitrogen. Observe under microscope: 1. Whether the wafer has edge collapse; 2. Whether there is residual liquid; 3. Whether the AOI point number is qualified O: AOI point number <100; X: AOI point number >100.

[0046] 4. Whether the electrode has corrosion; The results are shown in Table 2.

[0047] Table 2

[0048] It can be seen from Tables 1 and 2 that the cutting protection liquid composition prepared in the examples is stable, can greatly reduce the surface tension of the system under high dilution conditions, has excellent wettability and permeability. The cutting liquid is easy to rinse and has no residue, which can improve the cleaning ability of the particles and will not corrode the metal to damage the electrode, and can protect the wafer from damage during cutting.

[0049] Compared with Example 1, no surfactant was added in Comparative Example 1, which caused serious residual liquid on the wafer during cutting, serious residual GaAs powder, wafer edge collapse, and metal electrode corrosion.

[0050] Compared with Example 2, alkyl glycoside was selected as the wetting agent in Comparative Example 2, and the system was uniform and stable, but the wettability was general, there was no obvious residual liquid after cutting, but a small amount of particles remained on the wafer surface, AOI was abnormal, and the electrode on the wafer surface was obviously corroded.

[0051] Compared with Example 3, the intermediate II of A was selected as the surfactant in Comparative Example 3, which had qualified wettability and no electrode corrosion, but had slow defoaming speed and a small amount of GaAs particle residues during cutting, causing AOI abnormality.

[0052] Compared with Example 4, the intermediate I of A was selected as the surfactant in Comparative Example 4, which had a uniform and stable system, qualified wettability, and relatively less GaAs powder residues during cutting, but the electrode was obviously corroded, causing AOI abnormality.

[0053] Compared with Example 5, the amount of wetting agent was increased without using surfactant in Comparative Example 5, which had good system stability, but the wafer protection ability was general, and there were electrode corrosion and cleaning residues.

[0054] Compared with Example 6, the higher dosage of surfactant B was used in Comparative Example 6, and the liquid medicine was stable and no electrode corrosion occurred. However, the edge collapse phenomenon occurred during the cutting process, and the gallium arsenide particles could not be completely washed, and the cleaning effect was poor.

[0055] From the above examples and comparative examples, it can be seen that the non-ionic gemini surfactant A has a lower critical micelle concentration, lower foaming property and better wetting property, the addition of which can stabilize the system, improve the cleaning ability of the particles, and will not cause corrosion damage to the metal electrode.

[0056] In summary, the positive progress of the present application is that by adding non-ionic gemini surfactant and adjusting the content of wetting agent, dispersant and penetrating agent, the surface tension is greatly reduced, the wetting property is improved, there is no obvious foam during the cutting process, the particles generated during the cutting process have good dispersion and cleaning ability, the metal electrode can be protected, and it has no metal impurity ions, does not corrode the wafer, is easy to rinse, has low toxicity, has good water solubility, is friendly to the environment.

[0057] The above only describes the preferred embodiments of the present application, and any changes and modifications made within the scope of the patent application of the present application shall be included in the scope of the present application.

Claims

1. A wafer dicing protective liquid composition, characterized in that, Based on a total mass percentage of 100%, the components in the composition and their respective mass percentages are as follows: wetting agent 0.1-5%, penetrant 0.1-2%, dispersant 0.1-2%, pH adjuster 0.01-5%, nonionic Gemini surfactant 0.1-2%, and the balance being water.

2. The wafer dicing protective fluid composition according to claim 1, characterized in that, The chemical structural formula of the nonionic Gemini surfactant is as follows: ， Where n is an integer between 5 and 10.

3. The wafer dicing protective fluid composition according to claim 1, characterized in that, The wetting agent is selected from any one or more of the following: fatty alcohol polyoxyethylene ether, octylphenol polyoxyethylene ether, polyoxyethylene polyoxypropylene block copolymer, decyl glucoside, sodium dodecylbenzenesulfonate, sodium dodecyl sulfate, alkyl phosphate, α-olefin sulfonate, sodium lauroyl sarcosinate, and cocamidopropyl betaine.

4. The wafer dicing protective fluid composition according to claim 1, characterized in that, The penetrant is selected from any one or more of polyethylene glycol, sorbitol, mannitol, propylene glycol, secondary alcohol polyoxyethylene ether, sodium dodecyl sulfonate, diisooctyl maleate sulfonate, and isotridecyl ether phosphate.

5. The wafer dicing protective fluid composition according to claim 1, characterized in that, The dispersant is selected from any one or more of methylcellulose, carboxymethylcellulose, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, styrene-maleic anhydride copolymer, vinyl acetate-maleic anhydride copolymer, polyacrylic acid and its salts, polyvinylpyrrolidone, sulfonated polystyrene, and oleylamino oleate.

6. The wafer dicing protective fluid composition according to claim 1, characterized in that, The pH adjuster is selected from any one or more of potassium dihydrogen phosphate, disodium hydrogen phosphate, potassium hydroxide, sodium hydroxide, potassium hydrogen phthalate, sodium tetraborate, potassium tetraborate, monoethanolamine, diethanolamine, triethanolamine, diethylene glycolamine, N-butyldiethanolamine, and triethylamine.

7. The wafer dicing protective fluid composition according to claim 1, characterized in that, The water is high-purity water with a resistivity greater than 18 MΩ / cm.

8. The wafer dicing protective fluid composition according to claim 1, characterized in that, The method for preparing the composition is to add a wetting agent, a penetrant, a dispersant, and a nonionic Gemini surfactant to water, stir at 200 rpm to form a homogeneous system, then add a pH adjuster and mix evenly to obtain a homogeneous, stable, clear and transparent solution.

Images