Fragile material workpiece and production method of the same

Abstract

To provide a fragile material workpiece having excellent adhesive properties, adhesiveness, optical function, hydrophilic function and water-repellent function, and to provide a production method enabling efficient and highly accurate processing of a transparent fragile material.SOLUTION: A fragile material workpiece 1 has a fine groove region 3 in which a plurality of fine grooves 30 having a depth of 100 nm to 900 nm are aligned on a processed surface 2 of a fragile material 10 at intervals of 100 nm to 650 nm in a direction Y orthogonal to a drawing direction X of the fine grooves 30. The fragile material work piece 1 has an arithmetic average roughness (RA) of the processed surface 2 of 0.3 μm to 0.03 μm. A production method of the fragile material workpiece includes: a visualizing step of depositing a metal film and visualizing a processing object surface; a zero point confirming step of obtaining a zero point cutting depth by giving a trial cut within a film thickness range of the metal film, and measuring and calculating a width of a cut mark; a residual film thickness calculating step of obtaining a residual film thickness by calculation; and a main processing step of making a real cutting depth obtained by adding a desired cutting depth to the residual film thickness on the processing object surface so as to obtain the processed surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a brittle material workpiece having a machined surface with characteristic properties.The present invention relates to a method for manufacturing a brittle material workpiece by performing a characteristic cut on the machined surface of the brittle material. [Background technology]

[0002] BACKGROUND ART Adhesive structures in which nano-level protrusions are provided on the surface of an adherend have been known for some time. Patent Document 1 (JP 2023-115708 A) discloses an adhesive structure having a substrate and triangular wave-shaped protrusions provided on at least a portion of the surface of the substrate, the adhesive structure being made of an inorganic material, the triangular wave-shaped protrusions having an average pitch in the range of 100 nm or more and 1000 nm or less, and the triangular wave-shaped protrusions having an average height in the range of 100 nm or more and 1000 nm or less.

[0003] Patent Document 2 (JP 2023-115709 A) discloses an adhesive structure having a plurality of protrusions with sharp pointed tips. Patent Document 3 (JP 2023-115710 A) discloses an adhesive structure having a surface made of an inorganic material with a modulus of elasticity of 0.01 GPa or more and 50 GPa or less, and has an adhesive strength of 35 N / cm when a spherical indenter with a diameter of 40 μm is pressed into the surface using a nanoindenter under conditions of an indentation depth of at least 10 nm or 20 nm. 2 The above adhesive structure is shown.

[0004] Furthermore, Patent Documents 1 to 3 disclose NP processing (nano-pecking processing) as a cutting processing method for processing multiple protrusions on each bonded structure. In the NP processing, a blade is ultrasonically vibrated while being pressed obliquely into the surface of the inorganic material substrate, and then the blade is periodically moved up and down while being moved in a direction perpendicular to the blade surface. This forms protrusions on the surface of the inorganic material substrate, each having a plurality of inverted triangular grooves extending in a direction perpendicular to the direction of blade movement.

[0005] The adhesive structures of Patent Documents 1 to 3 each have a plurality of protrusions with different shapes, have high adhesive strength, and are less susceptible to decomposition or deterioration due to heat. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-115708 [Patent Document 2] Japanese Patent Application Publication No. 2023-115709 [Patent Document 3] Japanese Patent Application Publication No. 2023-115710 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, the adhesive structures of Patent Documents 1 to 3 have high adhesive strength. Furthermore, the multiple protrusions of Patent Documents 2 and 3 have body portions to increase the surface elastic modulus, which is effective in strengthening adhesive strength. The triangular wave-shaped protrusions of Patent Document 1 can be efficiently manufactured by the NP process, which is a cutting method, but it is difficult to efficiently cut the protrusions having body portions and pointed portions of Patent Documents 2 or 3 by the NP process. Furthermore, when the adhesive structures of Patent Documents 1 to 3 are subjected to the NP process on a brittle material such as glass, it is difficult to process regularly arranged protrusions, and there is a risk of cracks occurring in the protrusions.

[0008] When cutting a transparent brittle material, it is not possible to accurately visually confirm the surface of the workpiece, making it difficult to set the zero point of the cutting tool with high precision.

[0009] In view of the above circumstances, the present invention provides a brittle material processed product that has excellent adhesiveness and adhesion due to high friction, exhibits optical functions such as light diffusion, anti-reflection, and diffraction grating, has an antibacterial effect, and has hydrophilic and water-repellent functions. It also provides a method for manufacturing a brittle material processed product that enables more efficient and highly accurate zero-point setting of the processing surface of a transparent brittle material. [Means for solving the problem]

[0010] In order to solve at least one of the problems of the above-mentioned mounting structures, the present invention provides a brittle material processed product having a microgroove region on the processed surface of the brittle material, in which multiple microgrooves with a depth of 100 nm to 900 nm are arranged at intervals of 100 nm to 650 nm in a direction perpendicular to the extension direction of the microgrooves.

[0011] The brittle material processed product can be produced more efficiently by the NP processing. The microgroove region exhibits excellent adhesion and cohesion due to high friction, and also exhibits optical functions such as light diffusion, anti-reflection, and diffraction grating. Furthermore, the microgroove region has antibacterial properties and can exhibit hydrophilic and water-repellent functions.

[0012] If the depth of the microgrooves is outside the range of 100 nm to 900 nm, high adhesion may not be obtained. Furthermore, the depth of the microgrooves is preferably 200 nm to 800 nm. If the spacing between the microgrooves in the direction perpendicular to the extension direction is outside the range of 100 nm to 650 nm, high adhesion may not be obtained. The spacing between the microgrooves in the direction perpendicular to the extension direction may preferably be 200 nm to 550 nm.

[0013] The present invention may be directed to the brittle material processed product, wherein the processed surface has an arithmetic mean roughness (RA) of 0.3 μm to 0.03 μm. The processed surface having an arithmetic mean roughness (RA) of 0.3 μm to 0.03 μm can exhibit superior adhesiveness and adhesion. If the arithmetic mean roughness (RA) of the processed surface is outside the range of 0.3 μm to 0.03 μm, there is a risk of the adhesion being reduced, and the arithmetic mean roughness (RA) of the processed surface can be desirably set to 0.231 μm to 0.045 μm.

[0014] The present invention can be a brittle material processed product having a random area within the fine groove area of the processed surface in which multiple concave grooves having a width equivalent to multiple of the fine grooves are randomly scattered in a direction perpendicular to the extension direction of the fine grooves.

[0015] The brittle material workpiece having a random area in which multiple concave grooves are randomly scattered within the fine groove area can also exhibit higher adhesion than a workpiece having only the fine groove area or only the random area, depending on the brittle material in question.

[0016] The concave grooves in the random region can be cut as designed with the NP cutting tool, and cracks can be generated randomly due to brittle collapse during cutting with the cutting tool. This structure is suitable for brittle materials that are prone to cracks during cutting.

[0017] The present invention may also be directed to the brittle material workpiece, wherein the maximum height (PV) of the work surface is 7.0 μm to 4.0 μm. The processed surface having a maximum height (PV) in the range of 7.0 μm to 4.0 μm has better adhesion, while the processed surface having a maximum height (PV) outside the range of 7.0 μm to 4.0 μm is likely to have poor adhesion. The maximum height (PV) can be desirably set to 6.502 μm to 4.385 μm.

[0018] The present invention may be directed to the brittle material workpiece, wherein the root mean square roughness (RMS) of the work surface is 0.10 μm to 0.40 μm. The processed surface having a root mean square roughness (RMS) in the range of 0.10 μm to 0.40 μm has better adhesion, while the processed surface having a root mean square roughness (RMS) outside the range of 0.10 μm to 0.40 μm is likely to have poor adhesion. The root mean square roughness (RMS) can be 0.162 μm to 0.306 μm.

[0019] The present invention provides a brittle material processed product in which the contact angle of a water droplet in the extension direction of the microgroove on the processed surface is different from the contact angle of a water droplet in a direction perpendicular to the extension direction of the microgroove, and the product has anisotropy in the contact angle with a water droplet. The processed surface, which has anisotropy in the contact angle, can control the contact angle of a water droplet by adjusting the extension direction of the fine grooves.

[0020] The present invention provides the brittle material processed product, wherein the contact angle of a water droplet on the processed surface in the extension direction of the microgrooves is 110° to 80°, and the contact angle of a water droplet in the direction perpendicular to the extension direction of the microgrooves is 95° to 60°. The processed surface having a water droplet contact angle of 110° to 80° in the extension direction of the microgrooves and a water droplet contact angle of 95° to 60° in the direction perpendicular to the extension direction of the microgrooves can more clearly exhibit the anisotropy of the contact angle with water droplets.

[0021] When the contact angle of a water droplet in the extension direction of the microgrooves is outside the range of 110° to 80° and the contact angle of a water droplet in the direction perpendicular to the extension direction of the microgrooves is outside the range of 95° to 60°, the processed surface cannot clearly exhibit anisotropy of the contact angle with a water droplet. Furthermore, the contact angle of a water droplet in the extension direction of the microgrooves can be desirably 106.5° to 80.8°, and the contact angle of a water droplet in the direction perpendicular to the extension direction of the microgrooves can be desirably 94.05° to 60.4°.

[0022] The present invention may also be directed to the brittle material processed product, wherein the brittle material is silica glass or calcium fluoride glass. When the brittle material is quartz glass or calcium fluoride glass, it exhibits high adhesion, optical functions such as light diffusion, anti-reflection, and diffraction grating, has antibacterial effects, and exhibits hydrophilic and water-repellent functions. The brittle material may be glass, quartz crystal, silicon, ceramic, germanium, or the like.

[0023] The present invention includes a visualization step of depositing a metal film of a predetermined thickness on the surface of a transparent brittle material to be machined, thereby visualizing the surface of the material to be machined; and a zero point confirmation step of using a simple vibration ultrasonic cutting device to test cut within the thickness range of the metal film, measure the width of the cutting mark, and obtain the zero point cutting depth according to Equation 1.

[0024]

number

[0025] According to the method for manufacturing a brittle material workpiece, the zero point setting of the cutting tool for the transparent brittle material can be performed more efficiently and with higher precision. The metal film can be formed by vapor deposition or plating, and can be made of, for example, aluminum, chromium, zinc, gold, silver, platinum, nickel, copper, or the like. The width of the cutting mark is the width of a cutting mark made by trial cutting a blade of a simple vibration ultrasonic cutting device into the thickness range of the metal film. [Effects of the Invention]

[0026] The brittle material processed product of the present invention exhibits excellent adhesiveness and adhesion due to high friction. It exhibits optical functions such as light diffusion, anti-reflection, and diffraction grating. It has antibacterial effects. It has hydrophilic and water-repellent functions. The manufacturing method of the brittle material processed product of the present invention enables more efficient and highly accurate zero point setting of the processing surface of the transparent brittle material. [Brief explanation of the drawings]

[0027] [Figure 1] (A) Enlarged photograph of machined surface 2 of brittle material, which has random regions 4 within microgroove regions 3; (B) Enlarged side view of the cross section of machined surface 2 in Figure 1(A); (C) Enlarged photograph of microgroove region 3; (D) Enlarged photograph of random region 4. [Figure 2] (A) Enlarged photograph of surface 2 machined by NP machining of calcium fluoride glass (CaF2) with a single 200 nm cut, (B) Laser microscope image of a single 200 nm cut and surface roughness measurement results, (C) Enlarged photograph of surface 2 machined with multiple 200 nm cuts, (D) Laser microscope image of a multiple 200 nm cut and surface roughness measurement results [Figure 3] (A) Enlarged photograph of machined surface 2 with a 200 nm depth of cut, (B) Laser microscope image of a 200 nm depth of cut and surface roughness measurement results, (C) Enlarged photograph of machined surface 2 with a 2 μm depth of cut, (D) Laser microscope image of a 2 μm depth of cut and surface roughness measurement results of the machined surface 2 with a 2 μm depth of cut. [Figure 4] (A) Enlarged photograph of machined surface 2 with 400 nm cuts and 350 nm intervals, (B) Laser microscope image and surface roughness measurement results with 400 nm cuts and 350 nm intervals, (C) Enlarged photograph of machined surface 2 with 800 nm cuts and 350 nm intervals, (D) Laser microscope image and surface roughness measurement results with 800 nm cuts and 350 nm intervals, of calcium fluoride glass machined surface 2 by NP machining [Figure 5] (A) Enlarged photograph of machined surface 2 with 400 nm cuts and 200 nm intervals, (B) Laser microscope image and surface roughness measurement results with 400 nm cuts and 200 nm intervals, (C) Enlarged photograph of machined surface 2 with 400 nm cuts and 350 nm intervals, (D) Laser microscope image and surface roughness measurement results with 400 nm cuts and 350 nm intervals, (E) Enlarged photograph of machined surface 2 with 600 nm cuts and 550 nm intervals, (F) Laser microscope image and surface roughness measurement results with 600 nm cuts and 550 nm intervals [Figure 6] Regarding the contact angles of water droplets 7 and 70 on calcium fluoride glass, (A) comparative photographs of the plain surface 8 and the processed surface 2 (X and Y directions), (B) photographs of the extension direction (X) and perpendicular direction (Y) of the microgrooves 30 on the processed surface 2 and the water droplet 70 [Figure 7]Regarding the contact angle of a water droplet on calcium fluoride glass, (A) a photograph of 70 water droplets in the X and Y directions with NP processing, 400 nm cuts, and 200 nm intervals; (B) a photograph of 70 water droplets in the X and Y directions with NP processing, 600 nm cuts, and 550 nm intervals; (C) a photograph of 70 water droplets in the X and Y directions with NP processing, 400 nm cuts, and 350 nm intervals. [Figure 8] Regarding the contact angle of a water droplet 7 on quartz glass, (A) a comparative photograph of the plated surface 8 and the blasted (matt) surface 80, (B) an enlarged photograph of the matt surface 80 with blasted grain sizes of 10 to 20 μm, a laser microscope image, and the results of surface roughness measurements. [Figure 9] (A) Photographs of the metal film 21 on the plain surface 8, the matte finish portion 80, and the NP-processed surface 2 in an experiment on the adhesion of calcium fluoride glass thin films, (B) a photograph of the processed surface 2 with cellophane adhesive tape 9 attached, and (C) a photograph confirming the peeling of the metal film 21. [Figure 10] (A) Laser microscope image of the NP processed surface 2 and the matte finish portion 80 and the surface roughness measurement results of the calcium fluoride glass thin film adhesion experiment, (B) Photograph of the thin film adhesion experiment on the entire plain surface 8 [Figure 11] (A) Enlarged photograph of machined surface 2 by NP machining of quartz (SiO2) with a depth of cut of 200 nm or less (ductile mode), (B) Laser microscope image of machined surface 2 in Figure 11(A) and surface roughness measurement results, (C) Enlarged photograph of machined surface 2 with a depth of cut of 400 nm or more (brittle fracture mode, RA 0.25 μm), (D) Laser microscope image of machined surface 2 in Figure 11(C) and surface roughness measurement results, (E) Enlarged photograph of machined surface 2 with a depth of cut of 800 nm or more (brittle fracture mode, RA 0.4 μm), (D) Laser microscope image of machined surface 2 in Figure 11(E) and surface roughness measurement results [Figure 12] (A) Enlarged photograph of the pear-finished surface 80 with a particle size of 10-20 μm, (B) Laser microscope image of the pear-finished surface 80 in Figure 12(A) and the results of surface roughness measurement, (C) Enlarged photograph of the pear-finished surface 80 with a particle size of 15-35 μm, (D) Laser microscope image of the pear-finished surface 80 in Figure 12(C) and the results of surface roughness measurement, (E) Enlarged photograph of the pear-finished surface 80 with a particle size of 30-50 μm, (F) Laser microscope image of the pear-finished surface 80 in Figure 12(E) and the results of surface roughness measurement [Figure 13] (A) Enlarged photograph of the matte surface 80 obtained by shaping quartz, (B) Laser microscope image of the matte surface 80 in Figure 13(A) and measurement results of surface roughness, (C) Enlarged photograph of the matte surface 80 obtained by other shaping, (D) Laser microscope image of the matte surface 80 in Figure 13(C) and measurement results of surface roughness [Figure 14] A side view of the single-vibration ultrasonic vibration cutting device 50 and the jig 6. [Figure 15] Regarding machining using the single vibration ultrasonic vibration cutting device 50, (A) a side view showing machining using the single vibration ultrasonic vibration cutting device 50, (B) a side view showing machining of the fine groove region 3, and (C) a side view showing machining of the random surface region 4. [Figure 16] Regarding the zero point confirmation process of the blade 51, (A) is a front cross-sectional view showing the blade 51 cutting into the processing target surface 20 and the width (W) of the cutting mark, and (B) is a side cross-sectional view showing each dimension of the blade 51 from the zero point confirmation process to the main processing process. [Figure 17] Regarding machining using the single-vibration ultrasonic vibration cutting device 50, (A) is a perspective view showing machining using the single-vibration ultrasonic vibration cutting device 50, (B) is a perspective view showing the cutting state of the blade 51, and (C) is a side cross-sectional view showing the cutting state of the blade 51. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, a brittle material workpiece and a manufacturing method thereof according to this embodiment will be specifically described with reference to the drawings. In particular, this embodiment is a brittle material workpiece 1 having a brittle material 10 with a work surface 2 having a microgroove region 3 in which a plurality of microgrooves 30 with a depth of 100 nm to 900 nm are arranged at intervals of 100 nm to 650 nm in a direction Y perpendicular to the extension direction X of the microgrooves 30, and the arithmetic mean roughness (RA) of the work surface 2 of the brittle material workpiece 1 is 0.3 μm to 0.03 μm.

[0029] The brittle material workpiece 1 shown in Figure 1(A) is obtained by NP (Nano-Becker) machining of a workpiece surface 20 of a brittle material 10 made of quartz (SiO2) using a simple vibration ultrasonic vibration cutting device 50 shown in Figure 15(A). The machined surface 2 has a microgroove region 3 in which a plurality of microgrooves 3 with a depth of 200 nm to 800 nm are arranged at intervals (texture) of 200 nm to 550 nm in a direction Y perpendicular to the extension direction X of the microgrooves 3. The microgroove region 3 has a random region 4 in which a plurality of concave grooves 40, each having a width equivalent to a plurality of the microgrooves 30, are randomly scattered in a direction Y perpendicular to the extension direction X of the microgrooves 30.

[0030] 1(B) and 15(A), the cutting depth of the blade 51 of the simple vibration ultrasonic vibration cutting device 50 can be controlled with respect to the machining surface 2 of the brittle material workpiece 1, so that the fine groove regions 3 and random regions 4 are randomly mixed. In the process of machining the fine groove regions 3 with the blade 51 in a brittle fracture mode, the machining surface 2 is formed so that the plurality of concave grooves 40 consisting of a plurality of cracks are randomly scattered on the machining target surface 20, and the fine groove regions 3 and random regions 4 can be irregularly mixed. The processed surface 2, in which the fine groove regions 3 and random regions 4 are randomly mixed, increases the surface area, increases friction, and improves adhesion.

[0031] The entire processed surface 2 in Figure 1(C) is made up of the microgroove region 3. Because the microgroove region 3 is transparent, it can be used for optical purposes, and is particularly suited to controlling optical properties. Possible uses and functions include improved adhesion, diffraction grating, anti-reflection, hydrophilic effect, water-repellent effect, antibacterial effect, and increased coefficient of friction.

[0032] The processed surface 2 in Figure 1(D) is almost entirely made up of the random regions 4. Because the random regions 4 are cloudy, they are difficult to use for optical purposes, and are therefore particularly suited to controlling surface properties. Possible uses and functions include improved adhesion, increased friction coefficient, light diffusion effect, hydrophilic properties, and water-repellent properties.

[0033] The machined surface 2 shown in Figures 2(A) and (B) has a brittle material 10 made of calcium fluoride glass (CaF2). The machining conditions were NP machining, with a single cut (cut) to a depth of 200 nm. A fine groove region 3 is formed over the entire surface of the machined surface 2, and the fine grooves 30 are more regularly arranged than in quartz, which will be described later. Surface roughness data is shown in Table 1.

[0034] [Table 1]

[0035] The machined surface 2 shown in Figures 2(C) and (D) is a result of NP machining conditions in which multiple cuts (cuts) were made to a depth of 200 nm into a brittle material 10 made of calcium fluoride glass. Compared to a single cut, a deeper microgroove region 3 was formed across the entire surface of the machined surface 2. The microgrooves 30 are more regularly arranged than in quartz, which will be described later. Surface roughness data is shown in Table 1 above.

[0036] The machined surface 2 shown in Figures 3(A) and (B) was obtained by shaping a brittle material 10 made of calcium fluoride glass under the machining conditions of 200 nm cutting depth. This shaping is a type of NP machining in which the blade is moved perpendicular to the blade surface rather than periodically moving up and down. The state of the machined surface 2 is such that the fine grooves 30 are more regularly arranged than in quartz, which will be described later. Even with a deep cutting depth in the shaping, a mirror finish is obtained. Surface roughness data is shown in Table 2.

[0037] [Table 2]

[0038] The processed surface 2 shown in Figures 3(C) and (D) is a cutting condition for a depth of 2 μm in a brittle material 10 made of calcium fluoride glass using the shaper processing. The state of the processed surface 2 is substantially the same as that of the cutting depth of 200 nm shown in Figures 3(A) and (B). The surface roughness data is shown in Table 2.

[0039] The processed surface 2 shown in Figures 4(A) and (B) was created by cutting (cutting) a calcium fluoride glass brittle material 10 to a depth of 400 nm, with NP processing conditions of 350 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. The state of the processed surface 2 is such that the microgrooves 30 are arranged in a more orderly manner than in quartz, which will be described later. The microgrooves 30 can be shaped to a certain extent, but are less likely to have a clear shape than in metal. The crater-like shape is due to the influence of the blade used in the base processing and is not caused by the NP processing. The crater-shaped portions can be the concave grooves 40 and random regions 4. Surface roughness data is shown in Table 3.

[0040] [Table 3]

[0041] The processed surface 2 shown in Figures 4(C) and (D) was obtained by cutting (cutting) a calcium fluoride glass brittle material 10 to a depth of 800 nm, with the spacing of the microgrooves 30 in the direction Y perpendicular to the extension direction being 350 nm, under NP processing conditions. The state of the processed surface 2 is substantially the same as that shown in Figures 4(A) and (B). The surface roughness data is shown in Table 3.

[0042] The machined surface 2 shown in Figures 5(A) and (B) was created by cutting (cutting) a calcium fluoride glass brittle material 10 to a depth of 400 nm, with NP processing conditions of 200 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. The state of the machined surface 2 is such that the microgrooves 30 are arranged in a more orderly fashion than in quartz, which will be described later. It is difficult to obtain a clear microgroove 30 shape like that of metal. It appears that a shape similar to the shape shown in Figure 1(A), which produced good results with quartz (high friction coefficient), can be easily obtained. Crater-shaped areas can be the concave grooves 40 and random regions 4. Surface roughness data is shown in Table 4.

[0043] [Table 4]

[0044] The processed surface 2 shown in Figures 5(C) and (D) was obtained by cutting (cutting) a calcium fluoride glass brittle material 10 to a depth of 400 nm, with NP processing conditions of 350 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. The state of the processed surface 2 is substantially the same as that shown in Figures 5(A) and (B), although the microgrooves 30 are deeper and the random regions 4 are slightly increased. Surface roughness data is shown in Table 4.

[0045] The processed surface 2 shown in Figures 5(E) and (F) was created by cutting (cutting) a calcium fluoride glass brittle material 10 to a depth of 600 nm, with NP processing conditions of 550 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. The state of the processed surface 2 is substantially similar to that shown in Figures 5(C) and (D), although the microgrooves 30 are deeper and the random regions 4 are increased. Surface roughness data is shown in Table 4.

[0046] (Contact angle of water droplet) The contact angles of the water droplets 7 and 70 shown in Figure 6(A) were measured by comparing the brittle material workpiece 1 (machined surface 2) made of calcium fluoride glass with a comparison product (plain surface 8) made of the same material. The plain surface 8 is an unmachined surface. The brittle material workpiece 1 and the comparison product were ultrasonically cleaned with ethanol for 5 minutes, and 2 μL of pure water was dropped onto the horizontally placed machined surface 2 and plain surface 8, respectively.

[0047] The machined surface 2 of the brittle material workpiece 1 is cut to a depth of 400 nm under NP machining conditions, with the spacing of the microgrooves 30 in the direction Y perpendicular to the extension direction being 350 nm. The machined surface 2 shown in Figures 6(A) and (B) has anisotropy in the contact angle of the water droplet 70 in the X and Y directions. The water droplet 7 on the plain surface 8 does not have anisotropy.

[0048] Figure 7(A) shows a water droplet 70 dropped on the processed surface 2 under NP processing conditions of a 400 nm deep cut (cutting) and a 200 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. Figure 7(B) shows a water droplet 70 dropped on the processed surface 2 under NP processing conditions of a 600 nm cut and a 550 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. Figure 7(C) shows a water droplet 70 dropped on the processed surface 2 under NP processing conditions of a 400 nm deep cut (cutting) and a 550 nm spacing in the direction Y perpendicular to the extension direction of the microgrooves 30. Although the NP processing conditions are the same as those for the processed surface 2 shown in Figures 6(A) and (B), the contact angle changes depending on experimental conditions such as room temperature. Under all experimental conditions, the contact angles in the X and Y directions are anisotropic. Table 5 shows data on the contact angles of the water droplets 70 in FIGS. 6(A), (B) and 7(A) to (B).

[0049] [Table 5]

[0050] Figure 8(A) shows a water drop 7 with a contact angle of 49.4° on a plain quartz surface 8 and a contact angle of 31.2° on a blasted quartz surface 80. As shown in Figure 8(B), the blasted surface 80 was blasted using a shot blasting agent with a particle size of 10-20μm, and its arithmetic mean roughness (Ra) was 0.447μm. Table 6 compares the contact angles.

[0051] [Table 6]

[0052] (thin film adhesion) 9(A) shows a brittle material workpiece 1 in which a plain portion 8, a matte finish portion 80 (shaper processing area), and an NP processed portion 2 (NP processing area) are arranged on the processing target surface 20 of a single brittle material 10 made of calcium fluoride glass. A pure copper film 21 with a thickness of approximately 400 nm is vapor-deposited by sputtering on the plain portion 8, matte finish portion 80, and NP processed portion 2 of the brittle material workpiece 1. The transparent portions are masked for fixation.

[0053] As shown in Figure 9(B), cellophane adhesive tape 9 (manufactured by Nichiban Co., Ltd.) was cut to a width of approximately 3 mm and attached to the plain portion 8, matte portion 80, and NP processed portion 2. It was lightly rubbed with a cotton swab to allow it to blend in, and then peeled off. As shown in Figure 9(C), the pure copper film 21 on the plain portion 8 peeled off easily. The NP processed portion 2 did not peel off. The matte portion 80 also did not peel off. The NP processed portion 2 was subjected to a peel test several times in different directions, but it did not peel off.

[0054] 10(A) shows laser microscope images and surface roughness measurement results of the NP processed portion 2 and the matte finish portion 80. The NP processed portion 2 has a (PV) of 3.978 μm, an (RMS) of 0.159 μm, and an (RA) of 0.085 μm, while the matte finish portion 80 has a (PV) of 4.515 μm, an (RMS) of 0.218 μm, and an (RA) of 0.105 μm.

[0055] 10(B), a pure copper film 21 was vapor-deposited on a calcium fluoride glass brittle material 10 having a plain surface 8 on the entire surface. In a confirmation experiment, the cellophane adhesive tape 9 (manufactured by Nichiban Co., Ltd.) was applied in the same manner as described above and then peeled off. As a result, the pure copper film 21 was easily peeled off. The improvement in adhesion of the NP processed portion 2 is clear.

[0056] (NP processing of quartz) 11(A) and (B) show the machined surface 2 under NP machining conditions with a ductile mode depth of cut (depth of 200 nm or less). Microgrooves 30 are arranged in an orderly fashion, and the surface is relatively smooth with a maximum height (PV) of 0.340 μm, a root mean square roughness (RMS) of 0.011 μm, and an arithmetic mean roughness (RA) of 0.009 μm.

[0057] Figures 11(C) and (D) show the machined surface 2 under NP machining conditions with a cutting depth (RA 0.25 μm) in brittle fracture mode (depth 400 nm or more). Concave grooves 40 appear, and the maximum height (PV) is 7.055 μm, the root mean square roughness (RMS) is 0.311 μm, and the arithmetic mean roughness (RA) is 0.219 μm. Although some roughness is observed, the surface is homogeneous.

[0058] Figures 11(E) and (F) show the machined surface 2 under NP machining conditions with a cutting depth (RA 0.4 μm) in brittle fracture mode during cutting (depth 800 nm or more). Large concave grooves 40 appear, and the roughness is large, with a maximum height (PV) of 9.251 μm, a root mean square roughness (RMS) of 0.624 μm, and an arithmetic mean roughness (RA) of 0.459 μm, but the surface is generally homogeneous.

[0059] (Quartz blasting) Figures 12(A) and (B) show matte surfaces 80 that have been blasted with shot material having a particle size of 10 to 20 μm. Figures 12(C) and (D) show matte surfaces 80 that have been blasted with shot material having a particle size of 15 to 35 μm. Figures 12(E) and (F) show matte surfaces 80 that have been blasted with shot material having a particle size of 30 to 50 μm. The roughness of each matte surface 80 varies depending on the particle size, and many crushed areas can be seen. Compared to NP processing, the unevenness appears to be more rounded.

[0060] (Quartz shaper processing) Figures 13(A), (B), (C), and (D) show matte surfaces 80 that have been subjected to shaper processing with different cutting depths. Although the roughness can be changed by the cutting depth, it is difficult to control. The surface is prone to large cracks. Table 7 shows the surface roughness data of each processed surface 2 of the NP processing and each matte surface 80 of the blast processing and shaper processing.

[0061] [Table 7]

[0062] (NP processing) As shown in Figures 14 and 17(A) to 17(C), the NP (Nano Becker) machining can use a machining device 5 having a blade 51 and an ultrasonic vibration device 50 (e.g., a simple vibration ultrasonic vibration cutting device 50) that ultrasonically vibrates the blade 51. The shape of the blade surface of the blade 51 is not particularly limited and can be, for example, a rounded surface with a predetermined radius of curvature, a triangle, a rectangle, or the like. In the NP machining, for example, the blade 51 is ultrasonically vibrated while being pressed obliquely into the workpiece surface 20 of the brittle material 10, and then the blade 51 is moved in a direction (Y) perpendicular to the blade surface while periodically moving the blade 51 up and down. This forms triangular wave-shaped protrusions on the workpiece surface 20 of the brittle material 10, each having a plurality of inverted triangular microgrooves 30 extending in a direction (X) perpendicular to the movement direction of the blade 51.

[0063] As shown in Figure 15(B), when the cutting depth D2 of the blade 51 is set to 200 nm or less, a microgroove region 3 in which the microgrooves 30 are arranged in an orderly fashion can be formed. The blade 51 moves up and down in the direction of the white arrow (Y). As shown in Figure 15(C), when the cutting depth D2 of the blade 51 is set to 400 nm or more, random regions 4 in which concave grooves 40 are randomly scattered within the microgroove region 3 appear, or a machined surface 2 consisting only of random regions 4 is obtained.

[0064] (Brittle material) The brittle material 10 can be a high-precision base material equivalent to spring water or anhydrous quartz. Flatness and thickness tolerance is +0.00023 nm or less, inspection level (scratches, bubbles, etc.) S / D 60-40 (fluorescent lamp level) S / D 40-20 (concentrated lamp level), parallelism 30 seconds (in-plane thickness difference of about 0.001745 nm).

[0065] As a processing condition, after the brittle material 10 is fixed, it is necessary to check the plane distortion on the processing machine. Since distortion must be less than the processing depth, the brittle material 10 must also be in a highly accurate flat state. The brittle material 10 can be, for example, a flat plate of 12 mm x 12 mm x 1 mm.

[0066] The brittle material 10 is supported by the mask plate 62 and fixed by suction to the suction plate 60. After fixing, the state of the processing target surface 20 (upper surface) of the brittle material 10 is checked on the machine using a laser displacement meter or the like. The amount of displacement can be controlled to 500 nm or less.

[0067] The simple vibration ultrasonic vibration cutting device 50 is driven at, for example, 20 kHz, and a single crystal special diamond cutting tool is attached as the cutting tool 51. The cutting tool 51 has a tip curvature radius (R) of 10 mm, a cutting edge width of 1.5 mm, and is free of chipping (edge chipping) of about 100 nm or less when observed under an electron microscope at 30,000 magnifications.

[0068] (Setting the zero point of blade 51) 16(A) and 16(B), when performing fine cutting on a transparent brittle material 10 such as glass, it is difficult to visually confirm the contact point between the work surface 20 of the brittle material 10 and the blade 51, making it difficult to set the zero point of the blade 51. To solve this problem, the manufacturing method of a brittle material workpiece according to this embodiment described below is effective.

[0069] (Visualization process) A metal film 21 of a predetermined thickness (T1) is vapor-deposited on the processing target surface 20 of the brittle material 10 to visualize the processing target surface 20. The thickness (T1) of the metal film 21 can be set to, for example, 500 nm. If the desired cutting depth is 700 nm, the thickness (T1) of the metal film 21 can be set to 500 nm + cutting depth (D2) to 200 nm.

[0070] (Zero point confirmation process) Using the simple ultrasonic vibration cutting device 50, a test cut is made within a film thickness (T1) of 500 nm of the metal film 21, the width (W) of the cutting mark is measured, and the zero point cutting depth (D1) is obtained according to Equation 1.

[0071]

number

[0072] (Remaining film thickness calculation process) The zero point cutting depth (D1) is subtracted from the predetermined thickness (T1) of the metal film 21 to obtain the remaining thickness (T2).

[0073] (Main processing process) Using the simple vibration ultrasonic vibration cutting device 50, an actual cutting depth (T2+D2), which is the remaining film thickness (T2) plus a desired cutting depth (D2), is cut into the processing target surface 20 of the brittle material 10 to obtain a processed surface 2. When the actual cutting depth (T2+D2) has been cut, the metal film 21 has been removed by cutting.

[0074] Tables 8 and 9 show the advantages and disadvantages of each process other than NP processing, such as blast processing, shaper processing, photolithography, and elliptical vibration cutting.

[0075] [Table 8]

[0076] [Table 9]

[0077] Unlike the edged processed surface 2 of NP processing, the blast processing has a low effect of increasing friction. Shaper processing causes severe wear of the blade, and the processing cost for large areas is higher than that of NP processing. Photolithography (etching) is technically difficult because it involves drawing in grayscale. It is difficult to create a mask. Elliptical vibration cutting takes time to process, and the processing cost is higher than that of NP processing. [Industrial Applicability]

[0078] The brittle material processed product and its manufacturing method of the present invention can be used for elements, parts, devices, and their manufacture in the fields of friction, adhesion, adhesion, hydrophilicity, water repellency, antibacterial properties, optics, etc. [Explanation of symbols]

[0079] 1 Brittle material processed product 10 Brittle material (workpiece) 2 Machining surface (NP machining part) 20 Same as above Surface to be machined 21 Metal Film (R) Curvature radius of blade 51 (W) Width of the cutting mark (T1) Same specified film thickness (T2) Same residual film thickness (D1) Zero point cutting depth (D2) Desired cutting depth 3 Micro groove area 30 Same fine groove (X) Extension direction of the fine grooves 30 (Y) A direction perpendicular to the extension direction of the microgrooves 30 4 Random Area 40 Same concave groove 5 Processing equipment 50 Same as above Single Vibration Ultrasonic Vibration Cutting Device (Ultrasonic Vibration Device) 51 Same blade 52 Cutting fluid mist 7 water drops 70 Anisotropic water droplets 8 Plain part (plain surface) 80 Same as above, matte finish part (matte finish: shaper processed surface, blast processed surface) 9 Cellophane adhesive tape

Claims

1. A brittle material workpiece having a microgroove region in which a plurality of microgrooves having a depth of 100 nm to 900 nm are arranged at intervals of 100 nm to 650 nm in a direction perpendicular to the extension direction of the microgrooves on the work surface of the brittle material.

2. 2. The brittle material processed product according to claim 1, wherein the arithmetic mean roughness (RA) of the processed surface is 0.3 μm to 0.03 μm.

3. A brittle material workpiece as described in claim 1, wherein the microgroove region of the processed surface has a random region in which multiple concave grooves having a width equivalent to multiple microgrooves are randomly scattered in a direction perpendicular to the extension direction of the microgrooves.

4. The brittle material processed product according to any one of claims 1 to 3, wherein the maximum height (PV) of the processed surface is 7.0 μm to 4.0 μm.

5. The brittle material processed product according to any one of claims 1 to 3, wherein the root mean square roughness (RMS) of the processed surface is 0.10 µm to 0.40 µm.

6. A brittle material processed product according to any one of claims 1 to 3, wherein the contact angle of a water droplet in the extension direction of the microgrooves on the processed surface is different from the contact angle of a water droplet in a direction perpendicular to the extension direction of the microgrooves, and the contact angle with the water droplet is anisotropic.

7. a contact angle of a water droplet in the extension direction of the microgrooves on the processed surface of 110° to 80°; The contact angle of a water droplet in a direction perpendicular to the extension direction of the fine grooves is 95° to 60° 7. The brittle material processed product according to claim 6, wherein

8. The brittle material processed product according to any one of claims 1 to 3, wherein the brittle material is quartz glass or calcium fluoride glass.

9. a visualization step of depositing a metal film of a predetermined thickness on a surface of a transparent brittle material to be processed, thereby visualizing the surface; a zero-point confirmation step of using a simple vibration ultrasonic vibration cutting device to test cut into the metal film within the film thickness range, measuring the width of the cutting mark, and obtaining the zero-point cutting depth according to Equation 1; [Equation 1] a remaining film thickness calculation step of subtracting the zero point cut-in amount from the predetermined film thickness of the metal film to obtain a remaining film thickness; a main processing step in which an actual cutting amount, which is the remaining film thickness plus a desired cutting depth, is cut into the surface of the brittle material to be processed using the single-vibration ultrasonic vibration cutting device to obtain a processed surface.

Images