Method for improving surface smoothness of microstructure

Abstract

A method for improving surface smoothness of a microstructure relates to surface treatment of the microstructure, and comprises the following steps: S1, precise gluing: uniformly blade-coating a chemical decoration liquid on the surface of the microstructure, the chemical decoration liquid being a solvent-type photocuring liquid, the solvent-type photocuring liquid comprising a photocuring material and a solvent, the solvent being an alcohol or an ether, and the solvent being an organic solvent; the photo-curing material is a non-anaerobic photo-curing transparent adhesive tape, and the mass of the photo-curing material accounts for 5-25% of the total mass; s2, baking and leveling: placing the microstructure in an environment of 50-70 DEG C for 20-60 minutes, and drying the solvent to form a layer of free leveling surface; and S3, curing and forming: carrying out light curing and forming on the microstructure, wherein the local exposure energy of the surface of the microstructure is 300-400mJ / cm < 2 >. By modifying the surface of the microstructure, the problems of non-smooth burrs, impurity particles, cracks and the like on the surface of the microstructure are solved, the smoothness of the surface of the microstructure is improved, an ideal optical surface is achieved, and the optical diffusion efficiency of the microstructure is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the surface treatment of optical microstructure, in particular to a method for improving the surface smoothness of microstructure. BACKGROUND

[0002] The morphology of microstructure directly affects the optical effect of microstructure, and cracks, missing structure profiles, surface burrs and the like on the surface of microstructure will all reduce the surface smoothness of microstructure, resulting in reduced optical function of microstructure. A free smooth surface is an ideal optical structure surface, but the common microstructure surface has non-smooth burrs, impurity particles and other unwanted roughness surfaces at the bottom, which reduces the optical effect. In order to improve the optical effect of microstructure, it is very important to improve the surface smoothness of microstructure. SUMMARY

[0003] The present application provides a method for improving the surface smoothness of microstructure, which solves the problem of reduced optical effect caused by non-smooth burrs, impurity particles and other unwanted roughness surfaces on the surface of microstructure. The present application improves the surface smoothness of microstructure by modifying the surface of microstructure, so as to achieve an ideal optical surface and improve the optical effect of microstructure.

[0004] The technical scheme provided by the present application is as follows:

[0005] A method for improving the surface smoothness of microstructure, comprising the following steps:

[0006] S1. Precision gluing: uniformly scrape the chemical decoration liquid on the surface of microstructure, wherein the chemical decoration liquid is a solvent type photocuring liquid, the solvent type photocuring liquid comprises a photocuring material and a solvent, the solvent is an alcohol or ether solvent, and the photocuring material is a non-anaerobic type photocuring transparent adhesive, and the mass fraction of the photocuring material in the total mass is 5% to 25%;

[0007] S2. Baking and leveling: place the microstructure in an environment at 50 to 70℃ for 20 to 60min, dry the solvent, and form a layer of free leveling photocuring material surface;

[0008] S3. Curing and forming: photocuring forming is performed on the microstructure, and the local exposure energy of the surface of the microstructure is 300 to 400mJ / cm 2 .

[0009] The application strengthens the adhesion of the chemical decoration liquid to the surface of the microstructure by the components of the chemical decoration liquid and the proportion of each component, guarantees the hardness after solidification and molding, uniformly scrapes the chemical decoration liquid on the surface of the microstructure to avoid the generation of stripes or bubbles, controls the volatilization speed of the solvent by limiting the baking leveling environment (temperature and time) to avoid the problem of surface defects caused by excessive processing, controls the local exposure energy during the light curing molding process of the surface of the microstructure to ensure the quality and efficiency of solidification, and adopts a non-anaerobic light curing transparent adhesive as the light curing material, which can be directly cured in air without the need of an oxygen isolation environment, thereby simplifying the process flow.

[0010] Further, before step S1, the method further comprises: S0, microstructure surface pretreatment: adopting plasma cleaning or ultrasonic cleaning to remove the attachments on the surface of the microstructure.

[0011] In the application, before step S1, the surface of the microstructure is pretreated to clean the surface of the microstructure, so that the surface of the microstructure is dust-free and oil-free, thereby avoiding the interference of the attachments on the surface of the microstructure on the subsequent steps.

[0012] Further, the viscosity of the light curing material is 2000-3000 cps at 15-35℃.

[0013] In the application, the viscosity of the light curing material at 15-35℃ is limited to ensure the efficiency of subsequent solidification and improve the efficiency of the whole process.

[0014] Further, the solvent is ethanol or ethyl acetate.

[0015] In the application, the solvent is selected to be an alcohol or an ether that is easy to volatilize, which can meet the requirements. Considering the cost and convenience, the solvent is preferably ethanol or ethyl acetate.

[0016] Further, a limiting scraper is used in step S1 to control the uniform scraping and scraping thickness of the chemical decoration liquid.

[0017] In the application, the limiting scraper is used to control the uniform scraping of the chemical decoration liquid, so that stripes or bubbles are avoided during the scraping process.

[0018] Further, the limiting scraper is a thickness limiting film former, and the uniform scraping and scraping thickness of the chemical decoration liquid are controlled by the movement of the thickness limiting film former.

[0019] In the present application, a limited thickness film applicator is used as a limiting doctor blade, which facilitates the uniform coating of the chemical decoration liquid and ensures the uniformity of the coating; the coating thickness is strictly controlled to ultimately control the coating thickness of the chemical decoration layer, form a micro-nano level coating thickness, and further improve the surface finish of the microstructure.

[0020] Further, the coating thickness is 0.5-5 times the depth of the microstructure.

[0021] In the present application, by setting the relationship between the coating thickness and the depth of the microstructure, the local surface of the microstructure that is not filled due to insufficient surface tension or flowability during the coating process is compensated, and bubbles or voids are prevented.

[0022] Further, the coating thickness is positively correlated with the surface roughness of the microstructure.

[0023] In the present application, the greater the surface roughness of the microstructure, the greater the coating thickness, so that the recesses can be fully filled and bubbles or uncovered areas can be prevented. The greater the surface roughness of the microstructure, the more it will hinder the flow of the chemical decoration liquid, appropriately increase the coating thickness, and prolong the leveling time, which helps to ensure uniform coating.

[0024] Further, the surface roughness of the microstructure is 30-500 nm.

[0025] In the present application, the surface roughness of the microstructure is preferably ensured to ensure the contact area between the microstructure and the chemical decoration liquid, and to ensure that the surface finish of the microstructure is improved after chemical coating treatment, and the surface structure profile becomes clear and smooth. DETAILED DESCRIPTION

[0026] The terms used in the embodiment part of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0027] Embodiment one

[0028] A method for improving the surface finish of a microstructure, comprising the following steps:

[0029] S0. Microstructure surface pretreatment: plasma cleaning is used to remove the attachments on the surface of the microstructure.

[0030] During the microstructure surface pretreatment process, the surface of the microstructure is cleaned using plasma cleaning to ensure that the surface of the microstructure is dust-free and oil-free, so that the attachments on the surface of the microstructure are completely removed and interference with subsequent steps is avoided.

[0031] S1. Precise glue coating: uniformly coating the chemical decoration liquid on the surface of the microstructure.

[0032] Before precise gluing, the chemical decoration liquid is prepared first. The chemical decoration liquid is a solvent-based light-curing liquid, that is, the chemical decoration liquid includes a light-curing material and a solvent. Here, non-anaerobic light-curing transparent glue is selected as the light-curing material, and ethanol is selected as the solvent. Among them, the non-anaerobic light-curing transparent glue accounts for 5% of the total mass of the chemical decoration liquid.

[0033] Throughout the entire process, the composition and proportion of the chemical decorative liquid are controlled to enhance adhesion between the chemical decorative liquid and the microstructure surface, ensuring hardness after curing. During the scraping process, a limited scraper is used to control the uniform scraping of the chemical decorative liquid, ensuring uniformity and avoiding streaks or bubbles on the microstructure surface. At the same time, by strictly controlling the scraping thickness, the coating thickness formed by the chemical decorative liquid is controlled, achieving a micro-nano-level coating thickness and improving the surface finish of the microstructure.

[0034] Here, the use of non-anaerobic light-curing transparent adhesive as the light-curing material allows the entire scraping process to be completed without isolating oxygen, simplifying the process. Ethanol is chosen as the solvent because it is easily volatile, relatively easy to obtain, and relatively low in cost.

[0035] During the entire process, the coating thickness is controlled to be 5 times the depth of the microstructure. In this way, during the compensation coating process, the occurrence of partial unfilled surface of the microstructure due to insufficient surface tension or fluidity is avoided, and the generation of bubbles or voids is prevented.

[0036] During the whole process, the speed of uniform coating was controlled at 0.5 m / min to avoid the generation of bubbles or streaks.

[0037] S2. Baking and leveling: The microstructure coated with the chemical decoration liquid is placed in an environment of 50°C for 60 minutes to dry the ethanol and form a free-flowing light-curing material surface.

[0038] The baking and leveling environment is limited to 50℃ and 60min, so that the evaporation rate of the solvent can be controlled to avoid excessive processing and surface defects.

[0039] S3. Curing and molding: The baked and leveled microstructure is subjected to photocuring molding, and the local exposure energy on the microstructure surface is 300mJ / cm 2 .

[0040] Controlling the microstructure surface during the photocuring process, the local exposure energy is 300mJ / cm 2 control to ensure the quality and efficiency of curing.

[0041] Example 2

[0042] A method for improving the surface finish of a microstructure, comprising the following steps:

[0043] S0. Microstructure surface pretreatment: using ultrasonic cleaning to remove the attachments on the microstructure surface.

[0044] During the microstructure surface pretreatment process, the surface of the microstructure is cleaned using ultrasonic cleaning to ensure that the surface of the microstructure is free of dust and oil, etc., so that the attachments on the surface of the microstructure are completely removed, avoiding interference with the subsequent steps.

[0045] S1. Precision glue coating: uniformly coating the chemical decoration liquid on the microstructure surface.

[0046] Before precision glue coating, the chemical decoration liquid is prepared. The chemical decoration liquid is a solvent-based photocuring liquid, i.e., the chemical decoration liquid includes photocuring materials and solvents. Here, a non-anaerobic photocuring transparent adhesive with a viscosity of 2000-3000 cps at 15-35℃ is selected, and ethyl acetate is selected as the solvent. The photocuring materials account for 25% of the total mass of the chemical decoration liquid.

[0047] During the entire process, the composition of the chemical decoration liquid and the proportion of each component are controlled to strengthen the adhesion of the chemical decoration liquid to the surface of the microstructure and ensure the hardness after solidification and molding. During the coating process, a thickness film applicator is used as a limiting scraper to facilitate the uniform coating of the chemical decoration liquid, ensuring the uniformity of the coating and avoiding the formation of stripes or bubbles on the surface of the microstructure. At the same time, by strictly controlling the coating thickness, the coating thickness of the chemical decoration liquid is controlled to form a micro-nano level coating thickness, thereby improving the surface finish of the microstructure.

[0048] Here, the viscosity of the non-anaerobic photocuring transparent adhesive is limited to 15-35℃ to ensure the efficiency of subsequent solidification and improve the efficiency of the entire process. Ethyl acetate is selected as the solvent, which is easy to volatilize and relatively easy to obtain, with relatively low cost.

[0049] During the entire process, the coating thickness is controlled to be 0.5 times the depth of the microstructure. In this way, the situation of local incomplete filling of the microstructure surface due to surface tension or insufficient flowability during the coating process can be compensated for, preventing the formation of bubbles or voids.

[0050] During the entire process, the uniform coating speed is controlled to be 2 m / min to avoid the formation of bubbles or stripes.

[0051] S2. Baking and leveling: placing the microstructure coated with the chemical decoration liquid in an environment of 70℃ for 20 min to dry the solvent ethyl acetate and form a free-flowing photocuring material surface.

[0052] The baking leveling environment is defined, the temperature is 70℃, and the time is 20min, so as to control the solvent volatilization speed, avoid excessive processing, and cause surface defects, etc.

[0053] S3. Curing molding: the microstructure after baking leveling is cured and molded, the local exposure energy of the microstructure surface is 400mJ / cm 2 .

[0054] During the curing molding process of the microstructure surface, the local exposure energy is controlled to be 400mJ / cm 2 , to ensure the curing quality and efficiency.

[0055] During the curing process, a mercury lamp can be directly used to irradiate the microstructure after baking leveling, so as to facilitate the control of the irradiation time.

[0056] Embodiment three

[0057] A method for improving the surface finish of a microstructure, comprising the following steps:

[0058] S0. Microstructure surface pretreatment: adopt plasma cleaning to remove the attachments on the microstructure surface.

[0059] S1. Precision glue coating: uniformly scrape the chemical decoration liquid on the microstructure surface.

[0060] Before the precision glue coating, the chemical decoration liquid is configured. The chemical decoration liquid is a solvent type light curing liquid, the chemical decoration liquid includes light curing material and solvent, the non-anaerobic type light curing transparent adhesive is selected as the light curing material, and ethyl acetate is selected as the solvent, wherein the mass of the non-anaerobic type light curing transparent adhesive accounts for 10% of the total mass of the chemical decoration liquid.

[0061] The composition of the chemical decoration liquid and the proportion of each component are controlled to strengthen the adhesion of the chemical decoration liquid and the surface of the microstructure, and to ensure the hardness after curing molding. In the scraping process, the thickness film applicator is used as the limiting scraper, which facilitates the uniform scraping of the chemical decoration liquid, ensures the uniformity of the scraping, avoids the generation of stripes or bubbles on the surface of the microstructure, and strictly controls the scraping thickness to control the coating thickness formed by the chemical decoration liquid, forms the micro-nano level coating thickness, and improves the surface finish of the microstructure.

[0062] Here, the non-anaerobic type light curing transparent adhesive is used as the light curing material, and the whole scraping process can be completed without isolating oxygen, which simplifies the process flow. Ethyl acetate is selected as the solvent, ethyl acetate is easy to volatilize, and it is relatively easy to obtain and has relatively low cost.

[0063] Throughout the process, the control of the doctor blade thickness is 3 times the depth of the microstructure, so as to compensate for the doctor blade process, avoid the possible surface of the microstructure local filling situation caused by surface tension or lack of liquidity, prevent the generation of bubbles or voids.

[0064] Throughout the process, the uniform doctor blade speed is controlled at 1 m / min to avoid the generation of bubbles or stripes.

[0065] S2. Bake leveling: place the microstructure coated with chemical decoration liquid in an environment of 55°C for 50 minutes to dry the solvent ethyl acetate and form a layer of free-flowing light-cured material surface.

[0066] The bake leveling environment is defined as a temperature of 55°C and a time of 50 minutes, so as to control the evaporation speed of the solvent and avoid excessive processing and surface defects.

[0067] S3. Curing forming: bake the leveled microstructure to form a light-cured surface, and the local exposure energy of the microstructure surface is 330 mJ / cm 2 .

[0068] In the process of light-cured forming of the microstructure surface, the local exposure energy is controlled at 330 mJ / cm 2 to ensure the quality and efficiency of curing.

[0069] Example Four

[0070] A method for improving the surface finish of a microstructure, comprising the following steps:

[0071] S0. Microstructure surface pretreatment: ultrasonic cleaning is used to remove the attachments on the microstructure surface.

[0072] S1. Precision coating: uniformly coat the chemical decoration liquid on the microstructure surface.

[0073] Before precision coating, the chemical decoration liquid is prepared. The chemical decoration liquid is a solvent-based light-cured liquid, i.e. the chemical decoration liquid includes light-cured material and solvent. Here, a non-anaerobic light-cured transparent adhesive with a viscosity of 2000-3000 cps at 15-35°C is selected, and ethanol is used as the solvent. The light-cured material accounts for 15% of the total mass of the chemical decoration liquid.

[0074] Throughout the entire process, the composition and proportion of the chemical decorative liquid are controlled to enhance adhesion between the chemical decorative liquid and the microstructure surface, ensuring hardness after curing. During the scraping process, a thickness limiting film forming device is used as a limiting scraper to facilitate the uniform scraping of the chemical decorative liquid, ensuring uniformity and avoiding streaks or bubbles on the microstructure surface. At the same time, by strictly controlling the scraping thickness, the coating thickness formed by the chemical decorative liquid is controlled, achieving a micro-nano-level coating thickness, thereby improving the surface finish of the microstructure.

[0075] Here, the viscosity of the non-anaerobic light-curing transparent adhesive is limited to 15-35°C to ensure the efficiency of subsequent curing and improve the efficiency of the entire process. Ethanol is selected as the solvent because it is easily volatile, relatively easy to obtain, and relatively low in cost.

[0076] Throughout the process, the coating thickness is controlled to be twice the depth of the microstructure. This can compensate for the occurrence of partial unfilled areas on the surface of the microstructure due to surface tension or insufficient fluidity during the coating process, preventing the formation of bubbles or voids.

[0077] During the whole process, the speed of uniform coating was controlled at 1.5 m / min to avoid the generation of bubbles or streaks.

[0078] S2. Baking and leveling: Place the microstructure coated with the chemical decoration liquid in an environment of 60°C for 30 minutes to dry the solvent ethanol and form a layer of free-flowing light-curing material surface.

[0079] The baking and leveling environment is limited to 60℃ and 30min, so as to control the evaporation rate of the solvent and avoid excessive treatment, which may cause surface defects.

[0080] S3. Curing and molding: The baked and leveled microstructure is subjected to light curing molding, and the local exposure energy on the microstructure surface is 360mJ / cm 2 .

[0081] During the photocuring process to control the microstructure surface, the local exposure energy is 360mJ / cm 2 control to ensure the quality and efficiency of curing.

[0082] Microstructures with surface roughness of 20nm, 30nm, 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, and 550nm were selected and treated using the methods of Examples 1 to 4. Image analysis was performed on the treated microstructure surfaces to observe changes in the structural profile of the microstructure surface.

[0083]

[0084]

[0085] It is observed that after the microstructure surface is processed by the method of embodiments 1-4, the microstructure surface profile becomes clear and smooth, and the smoothness of the microstructure surface is further improved.

[0086] Further, by comparing microstructures with different surface roughness, the microstructure surface profile is observed after being processed by the method of embodiments 1-4. (The microstructure with a surface roughness of 20 nm is used as a reference)

[0087]

[0088]

[0089]

[0090] It is observed that the method of the present application has the best processing effect when the surface roughness of the microstructure is 30-500 nm. When the surface roughness of the microstructure is 30-500 nm, the contact area between the microstructure and the chemical decoration liquid is guaranteed, so that after the microstructure is processed by the chemical coating, the surface smoothness is improved, and the surface structure profile becomes clearer and smoother.

[0091] Microstructures with surface roughness of 30 nm, 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, and 500 nm are selected and processed by the method of embodiments 1-4, respectively, and the relationship between the scraping thickness and the mass ratio of the photocuring material is recorded, and the processing effect is compared.

[0092]

[0093]

[0094]

[0095] Statistical observation and analysis show that: when the scraping thickness is 0.5-5 times the depth of the microstructure, the processing effect is the best. Overall, when processing microstructures with the same roughness, the scraping thickness and the mass ratio of the photocuring material are negatively correlated, the larger the scraping thickness, the smaller the mass ratio of the photocuring material, so that the efficiency of the material is maximized.

[0096] Further, by comparing microstructures with different surface roughness, the microstructure surface profile is observed after being processed by the method of embodiments 1-4. (The microstructure with a surface roughness of 30 m is used as a reference)

[0097]

[0098]

[0099] Statistical observation analysis, microstructure in order to achieve the approximate degree of clarity and smoothness after processing, scraping thickness and microstructure surface roughness is positively correlated. The greater the surface roughness of the microstructure, the greater the scraping thickness, so that the recess can be filled sufficiently, preventing bubbles or uncovered areas. The greater the surface roughness of the microstructure, the flow of the chemical decoration liquid will be appropriately hindered, the scraping thickness will be appropriately increased, the leveling time will be prolonged, and the scraping uniformity will be helped.

[0100] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for improving the surface finish of a microstructure, characterized in that: The following steps are involved: S1. Precision Gluing: Evenly apply a chemical decorative liquid onto the surface of the microstructure. The chemical decorative liquid is a solvent-based light-curing liquid. The solvent-based light-curing liquid includes a light-curing material and a solvent. The solvent is an alcohol or ether solvent. The light-curing material is a non-anaerobic light-curing transparent adhesive, and its mass accounts for 5% to 25% of the total mass. S2 baking leveling: the microstructure is placed in an environment of 50 to 70 ° C for 20 to 60 min, the solvent is dried to form a free-leveling layer of the surface of the light-curing material; S3. Curing and molding: The microstructure is subjected to photocuring molding, and the exposure energy of the microstructure surface is 300 to 400 mJ / cm 2 .

2. The method according to claim 1, characterized in that Before step S1, the method further includes: S0. microstructure surface pretreatment: plasma cleaning or ultrasonic cleaning is used to remove attachments on the surface of the microstructure.

3. The method according to claim 1 or 3, characterized in that The light-curable material has a viscosity of 1000 to 3000 cps at a temperature of 15 to 35°C.

4. The method according to claim 1, wherein The solvent is ethanol or ethyl acetate.

5. The method according to claim 1, wherein In step S1, a limiting scraper is used to control the uniformity and thickness of the chemical decoration liquid.

6. The method according to claim 5, characterized in that The limiting scraper is a thickness limiting film maker, and the uniform scraping and coating thickness of the chemical decoration liquid are controlled by the movement of the thickness limiting film maker.

7. The method according to claim 5 or 6, characterized in that The scraping thickness is 0.5 to 5 times the depth of the microstructure.

8. The method according to claim 1, characterized in that The scraping thickness is positively correlated with the surface roughness of the microstructure.

9. The method according to claim 1, characterized in that The surface roughness of the microstructure is 30-500 nm.

10. The method according to claim 1, characterized in that In step S3, a mercury lamp is used to expose the surface of the microstructure.

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