Anti-scattering water-guided laser cutting fluid as well as preparation method and application thereof

Abstract

The invention provides anti-scattering water-guided laser cutting fluid as well as a preparation method and application thereof. The anti-scattering water-guided laser cutting fluid comprises the following components in parts by weight: 0.1-1 part of an anti-scattering agent; 0.01 to 0.1 part of a foam discharging agent; 1-5 parts of a refractive index regulator; and 80-99 parts of ultrapure water. The anti-scattering agent is a polymer; the foam removing agent is one or more of hydroxymethyl cellulose, hydroxy propyl cellulose, sodium lignin sulfonate, potassium lignin sulfonate and naphthalene sulfonic acid formaldehyde condensate sodium salt; the refractive index regulator is an iodine-containing compound and / or a fluorine-containing compound. According to the anti-scattering water-guided laser cutting fluid, light beam scattering and energy loss in the water-guided laser cutting process can be remarkably reduced, and the cutting precision and efficiency are improved. The anti-scattering water-guided laser cutting fluid has very good application prospects and large-scale industrial popularization potential in the field of water-guided laser cutting.

Description

Technical Field

[0001] The invention relates to cutting fluid technology, and in particular to an anti-scattering water-conducting laser cutting fluid, a preparation method and application thereof. Background Art

[0002] Water-guided laser cutting technology sprays a stream of water at the front end of the laser beam, allowing the laser beam to be more accurately transmitted to the cutting target. Currently, the water flow used by water-guided lasers is only ultrapure water, which brings some insurmountable technical problems. For example, tiny particles (bacteria and particulate impurities in the water) and bubbles in the water flow will cause scattering and energy loss of the laser beam, affecting the cutting effect and efficiency. This is a problem unique to water-guided laser cutting and does not exist in ordinary laser cutting.

[0003] In the traditional water-guided laser cutting process, ultrapure water is used as the cutting fluid. Particles and bubbles in the water flow will cause the following problems: 1) Beam scattering: When the laser passes through the water flow, tiny particles and bubbles in the water will scatter the laser beam, resulting in energy loss and deviation of the cutting path. 2) Energy loss: Scattering and absorption cause laser energy attenuation, reducing cutting efficiency. 3) Reduced cutting accuracy: The path deviation caused by beam scattering leads to reduced cutting accuracy, affecting the final processing quality. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of beam scattering, energy loss and reduced cutting accuracy caused by using ultrapure water as cutting fluid in the traditional water-guided laser cutting process, and to propose an anti-scattering water-guided laser cutting fluid, which can significantly reduce beam scattering and energy loss in the water-guided laser cutting process, and improve cutting accuracy and efficiency. The cutting fluid has very good application prospects and large-scale industrial promotion potential in the field of water-guided laser 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: an anti-scattering water-conductive laser cutting fluid, comprising the following components in weight proportions:

[0007] Anti-scattering agent 0.1-1 part;

[0008] Defoaming agent 0.01-0.1 part;

[0009] 1-5 parts of refractive index adjuster;

[0010] Ultrapure water 80-99 parts.

[0011] Furthermore, the anti-scattering agent is a polymer.

[0012] Furthermore, the anti-scattering agent is one or more of polyethylene glycol, polyvinyl pyrrolidone, polyacrylamide, polyurethane, polyethylene oxide, sodium polystyrene sulfonate, sodium polyacrylate and polyethylene imine.

[0013] Furthermore, the anti-scattering agent is preferably one or more of polymethyl methacrylate, polyethylene glycol, polyvinyl pyrrolidone and polyacrylamide.

[0014] Furthermore, the anti-scattering agent is preferably polyvinyl pyrrolidone.

[0015] Furthermore, the anti-scattering agent is 0.1-0.5 parts.

[0016] The anti-scattering agent can reduce the scattering of the light beam in the water flow. The specific mechanism is as follows: particle encapsulation, the anti-scattering agent can encapsulate the tiny particles in the water to make their surface smooth and reduce the interface scattering between the particles and the laser beam. Particle sedimentation, increasing the viscosity of the water flow, causing the tiny particles to settle and reducing the number of suspended particles.

[0017] The use of polyvinyl pyrrolidone as an anti-scattering agent also has the following advantages: 1) Optical properties: high solubility in water, simple preparation, high transparency, avoiding light energy attenuation, effectively reducing the scattering of the light beam in water, and improving cutting accuracy and efficiency. In addition, the concentration can be adjusted to match and reduce the beam deviation caused by refraction. 2) Particle encapsulation and sedimentation: The anti-scattering agent can not only efficiently encapsulate tiny particles in the water, but also slightly increase the viscosity of the water flow, accelerate particle sedimentation, and reduce the number of suspended particles. 3) Chemical stability: The chemical properties are stable in water, not easy to decompose or volatilize, and suitable for continuous work in a long-term laser environment. It is non-toxic and harmless, meets environmental protection requirements, and is suitable for large-scale industrial applications.

[0018] Furthermore, the defoaming agent is one or more of hydroxymethyl cellulose, hydroxypropyl cellulose, sodium lignin sulfonate, potassium lignin sulfonate and sodium salt of naphthalenesulfonic acid formaldehyde condensate.

[0019] Furthermore, the defoaming agent is preferably sodium lignin sulfonate.

[0020] Furthermore, the defoaming agent is 0.03-0.05 parts.

[0021] The defoaming agent can eliminate bubbles in the liquid and maintain the uniformity and stability of the liquid. Its mechanism of action mainly includes the following aspects: 1) Reducing surface tension: the defoaming agent can significantly reduce the surface tension of the liquid, making the bubbles easier to break. 2) Bubble breaking effect: the defoaming agent can destroy the membrane structure of the bubbles and cause the bubbles to collapse rapidly. 3) Bubble suppression effect: by forming a layer of hydrophobic film, it prevents the generation and aggregation of bubbles. 4) Promoting the rise of bubbles: making tiny bubbles quickly gather into larger bubbles, making it easier for the bubbles to rise to the surface of the liquid and break.

[0022] Furthermore, the refractive index adjuster is an iodine-containing compound and / or a fluorine-containing compound.

[0023] Furthermore, the refractive index adjuster is preferably one or more of sodium periodate, ammonium periodate, lithium periodate, potassium iodide, ammonium fluoride, ammonium bifluoride, sodium fluoride and potassium fluoride.

[0024] Furthermore, the refractive index adjuster is more preferably an iodine-containing compound.

[0025] Furthermore, the refractive index adjuster is more preferably sodium periodate.

[0026] Furthermore, the refractive index adjuster is 2-3 parts.

[0027] The refractive index adjuster can adjust the refractive index of the water flow to match the refractive index of the laser. The specific mechanisms are as follows: 1) Refractive index matching: By adjusting the refractive index of the solution to make it closer to the refractive index of the laser beam, the reflection and refraction loss of light at the interface are reduced. 2) Optical uniformity: Introducing high refractive index substances into the solution enhances optical uniformity and reduces the scattering and diffraction of the light beam in the medium. 3) Stability and consistency: The adjusted solution has higher optical stability, ensuring that the laser beam maintains a consistent propagation path during transmission.

[0028] Using sodium periodate as a refractive index adjuster also has the following advantages: the sodium periodate belongs to a monoclinic crystal system, and this structure has the characteristics of high symmetry and close packing, which helps to improve the optical uniformity and refractive index matching effect of the solution.

[0029] Furthermore, the ultrapure water is ultrapure water with a resistance of ≥ 18 megohms.

[0030] Furthermore, the ultrapure water is 90-95 parts.

[0031] The present invention adopts ultrapure water with a resistance of ≥18 megohms as a basic solvent to reduce impurities in the water.

[0032] Another object of the present invention is to disclose a method for preparing an anti-scattering water-conductive laser cutting fluid, comprising the following steps:

[0033] Step 1: Add ultrapure water to a mixing container and stir;

[0034] Step 2: Add anti-scattering agent, turn on the water bath and heat to 40-60°C, and stir;

[0035] Step 3: Turn off the water bath heating, wait for the liquid to cool, add the refractive index adjuster, and stir;

[0036] Step 4: Add defoaming agent and stir;

[0037] Step 5: Filter the above liquid to obtain anti-scattering water-conductive laser cutting fluid.

[0038] Furthermore, the stirring rate in step 1 is 40-80RPM.

[0039] Furthermore, in step 2, the stirring speed is 80-120RPM, and the stirring time is 1-3h.

[0040] Furthermore, the cooling in step 3 is natural cooling, cooling to 25-30°C.

[0041] Furthermore, the stirring rate in step 3 is 40-80RPM, and the stirring time is 30-50min.

[0042] Furthermore, the stirring rate in step 4 is 40-80RPM, and the stirring time is 30-50min.

[0043] Furthermore, the filtration in step 5 is carried out by filtering with a 0.5 μm+0.1 μm series filter element.

[0044] Another object of the present invention is to disclose an application of an anti-scattering water-conducting laser cutting fluid in the field of water-conducting laser cutting.

[0045] Furthermore, a method for cutting a semiconductor wafer using an anti-scattering water-conductive laser cutting fluid comprises the following steps:

[0046] S1. Use Swiss SYNOVA water-guided laser cutting machine, set the laser wavelength to 355nm, laser frequency to 600KHz, laser power to 1W, laser scanning rate to 600mm / s, water-guided cutting fluid flow rate to 10L / h, use water-guided cutting fluid and laser beam to process semiconductor wafers for cutting (such as Figure 1 As shown in the left figure);

[0047] S2. The cut wafer is cleaned with ultrapure water, and after cleaning, it is rotated at 1000-1500 r / min to evaporate water, thereby completing the laser cutting.

[0048] Compared with the prior art, the anti-scattering water-conductive laser cutting fluid, the preparation method and the application thereof of the present invention have the following advantages:

[0049] 1) The anti-scattering agent used in the present invention can reduce the light beam scattering in the water flow. The specific mechanism is as follows: Particle encapsulation, the anti-scattering agent can encapsulate the tiny particles in the water to make their surface smooth and reduce the interface scattering between the particles and the laser beam. Particle sedimentation, increasing the viscosity of the water flow, causing the tiny particles to settle and reducing the number of suspended particles.

[0050] The anti-scattering agent of the present invention is preferably polyvinyl pyrrolidone, because polyvinyl pyrrolidone has the following characteristics: Optical properties: high solubility in water, simple preparation, high transparency, avoiding light energy attenuation, and can effectively reduce the scattering of the light beam in water, improving cutting accuracy and efficiency. In addition, the concentration can be adjusted for matching to reduce the beam deviation caused by refraction. Particle encapsulation and sedimentation, anti-scattering agents such as polyvinyl pyrrolidone can not only efficiently encapsulate tiny particles in water, but also slightly increase the viscosity of the water flow, accelerate particle sedimentation, and reduce the number of suspended particles. Chemical stability: The chemical properties are stable in water, not easy to decompose or volatilize, and are suitable for continuous work in a long-term laser environment. Non-toxic and harmless, meets environmental protection requirements, and is suitable for large-scale industrial applications.

[0051] 2) The defoaming agent used in the present invention can eliminate bubbles in the liquid and maintain the uniformity and stability of the liquid. Its mechanism of action mainly includes the following aspects: reducing surface tension, the defoaming agent can significantly reduce the surface tension of the liquid, making the bubbles easier to break. Bubble breaking effect, the defoaming agent can destroy the membrane structure of the bubble and make the bubble disintegrate quickly. Bubble suppression effect, by forming a layer of hydrophobic film, prevent the generation and aggregation of bubbles. Promote the rise of bubbles, so that tiny bubbles quickly gather into larger bubbles, which is convenient for the bubbles to rise to the surface of the liquid and break.

[0052] 3) The refractive index adjuster used in the present invention can adjust the refractive index of the water flow to match the refractive index of the laser. The specific mechanism is as follows: Refractive index matching, by adjusting the refractive index of the solution to make it closer to the refractive index of the laser beam, the reflection and refraction loss of light at the interface are reduced. Optical uniformity, introducing high refractive index substances into the solution to enhance optical uniformity and reduce the scattering and diffraction of the light beam in the medium. Stability and consistency, the adjusted solution has higher optical stability to ensure that the laser beam maintains a consistent propagation path during transmission. The refractive index adjuster of the present invention is preferably sodium periodate, because sodium periodate belongs to the monoclinic crystal system, and this structure has the characteristics of high symmetry and close stacking, which helps to improve the optical uniformity and refractive index matching effect of the solution.

[0053] In summary, the novel anti-scattering water-based laser cutting fluid for water-based laser cutting of the present invention can reduce particles and bubbles in the water flow by adjusting the chemical composition and physical properties, significantly reduce beam scattering and energy loss, and improve cutting accuracy and efficiency. It has very good application prospects and large-scale industrial promotion potential in the field of water-based laser cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 Schematic diagram of water-guided laser cutting and conventional laser cutting;

[0055] Figure 2 This is the effect diagram of water-guided laser cutting using comparative example 4, with an optical microscope magnifying 100 times;

[0056] Figure 3 This is the effect picture of water-guided laser cutting using Example 1, magnified 100 times by an optical microscope;

[0057] Figure 4 This is a picture of the water-guided laser cutting effect of Comparative Example 1, magnified 100 times by an optical microscope. DETAILED DESCRIPTION

[0058] 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:

[0059] 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.

[0060] 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.

[0061] In the present specification, a numerical range expressed using "above" or "below" means a numerical range including the number.

[0062] In this specification, the word "may" means both performing a certain process and not performing a certain process.

[0063] 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.

[0064] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 15-25°C.

[0065] In this manual, the reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0066] Examples 1-8

[0067] Examples 1-8 disclose a variety of anti-scattering water-conductive laser cutting fluids, the components and weight ratios of which are shown in Table 1, and the preparation methods thereof are as follows:

[0068] Step 1: Add ultrapure water to the mixing container and turn on the stirrer at a stirring rate of 60 RPM;

[0069] Step 2: Add anti-scattering agent and turn on the water bath heating at 50°C. After all the anti-scattering agent is added, increase the stirring rate to 100 RPM and stir for 2 hours.

[0070] Step 3: Turn off the water bath heating, wait for the liquid to cool naturally to between 25-30°C, add the refractive index adjuster, stir at a rate of 60RPM, and stir for 30 minutes;

[0071] Step 4: Add defoaming agent, stir at 60 RPM, and stir for 30 minutes;

[0072] Step 5: Filter the above liquid through a 0.5μm+0.1μm series filter element to obtain a water-conducting laser cutting fluid.

[0073] Table 1 Components and weight ratios of anti-scattering water-conductive laser cutting fluids in Examples 1-8

[0074]

[0075]

[0076] Comparative Examples 1-4

[0077] Comparative Examples 1-4 disclose a variety of water-conducting laser cutting fluids, 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.

[0078] Table 2 Components and weight ratios of water-conducting laser cutting fluids in comparative examples 1-4

[0079]

[0080] The water-conducting laser cutting fluids of Examples 1-8 and Comparative Examples 1-4 were tested respectively, and the test results are shown in Table 3.

[0081] Table 3 Test data of Examples 1-8 and Comparative Examples 1-4

[0082]

[0083] As can be seen from Table 3, in Comparative Example 1, no anti-scattering agent was added, the number of suspended particles was large, the reflection loss increased, and the surface tension increased; in Comparative Example 2, no defoaming agent was added, the number of suspended particles was large, the reflection loss increased, and the surface tension increased; in Comparative Example 3, no refractive index adjuster was added, so the refractive index was low, the refractive index was close to that of pure water, and the reflection loss increased; in Comparative Example 4, only pure water had a surface tension of 72mN / m, the number of suspended particles was large, and the reflection loss increased.

[0084] Figure 1 This is a schematic diagram of the water-guided laser cutting principle; Figure 2 This is the effect diagram of water-guided laser cutting using comparative example 4 (parameters: laser wavelength 355nm, laser frequency 600KHz, laser power 1W, laser scanning rate 600mm / s), the optical microscope magnified 100 times, where the width of the heat-affected zone is 18.49μm. Figure 3 This is the effect diagram of water-guided laser cutting in Example 1 (parameters: laser wavelength 355nm, laser frequency 600KHz, laser power 1W, laser scanning rate 600mm / s), the optical microscope magnified 100 times, where the width of the heat-affected zone is 3.62μm. Figure 4 This is the effect diagram of water-guided laser cutting using comparative example 1 (parameters: laser wavelength 355nm, laser frequency 600KHz, laser power 1W, laser scanning rate 600mm / s), the optical microscope magnified 100 times, where the width of the heat-affected zone is 9.20μm.

[0085] Test method:

[0086] Refractive index test method: Use Abbe refractometer to test.

[0087] Suspended particle number test method: Use the Liyin particle counter to test.

[0088] Surface tension test method: Use a static surface tension meter to test.

[0089] Laser energy testing method: Use laser cutting machine energy detection.

[0090] Heat affected zone test method: Observe the cutting path condition with a microscope and mark the abnormal area farthest from the cutting path as the heat affected zone width.

[0091] 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. An anti-scattering water-conductive laser cutting fluid, characterized in that: The composition includes the following components in weight ratio:

2. The anti-scattering water-conductive laser cutting fluid according to claim 1, characterized in that: The anti-scattering agent is a polymer.

3. The anti-scattering water-conductive laser cutting fluid according to claim 1 or 2, characterized in that: The anti-scattering agent is one or more of polyethylene glycol, polyvinyl pyrrolidone, polyacrylamide, polyurethane, polyethylene oxide, sodium polystyrene sulfonate, sodium polyacrylate and polyethylene imine.

4. The anti-scattering water-conductive laser cutting fluid according to claim 1, characterized in that: The defoaming agent is one or more of hydroxymethyl cellulose, hydroxypropyl cellulose, sodium lignin sulfonate, potassium lignin sulfonate and sodium salt of naphthalenesulfonic acid formaldehyde condensate.

5. The anti-scattering water-conductive laser cutting fluid according to claim 1 or 4, characterized in that: The defoaming agent is sodium lignin sulfonate.

6. The anti-scattering water-conductive laser cutting fluid according to claim 1, characterized in that: The refractive index adjuster is an iodine-containing compound and / or a fluorine-containing compound.

7. The anti-scattering water-conductive laser cutting fluid according to claim 1 or 6, characterized in that: The refractive index adjuster is one or more of sodium periodate, ammonium periodate, lithium periodate, potassium iodide, ammonium fluoride, ammonium bifluoride, sodium fluoride and potassium fluoride.

8. The anti-scattering water-conductive laser cutting fluid according to claim 1, characterized in that: The ultrapure water is ultrapure water with a resistance of ≥18 megohms.

9. A method for preparing the anti-scattering water-conductive laser cutting fluid according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: Add ultrapure water to a mixing container and stir; Step 2: Add anti-scattering agent, turn on the water bath and heat to 40-60°C, and stir; Step 3: Turn off the water bath heating, wait for the liquid to cool, add the refractive index adjuster, and stir; Step 4: Add defoaming agent and stir; Step 5: Filter the above liquid to obtain anti-scattering water-conductive laser cutting fluid.

10. Use of the anti-scattering water-conducting laser cutting fluid according to any one of claims 1 to 8 in the field of water-conducting laser cutting.

Images