Method for manufacturing glass article, and glass article

Abstract

Provided are: a method for manufacturing a glass article, in which the energy of fumes (a vaporization product) generated during a processing by laser irradiation is reduced to thereby prevent the adhesion of the fumes onto the glass surface and enable the easy removal of debris, and with which the deterioration of strength of a support glass substrate can be suppressed; and a glass article. In the method for manufacturing a glass article, a laser processing is performed using a pulse laser 1, wherein the conditions for a laser used in the laser processing are such that the output level is 1 W or less and the laser processing is performed by irradiating, several times, a line L along which the laser processing is intended to be performed. The pulse laser 1 is a femtosecond laser.

Description

Glass article manufacturing method and glass article

[0001] The present invention relates to a method for manufacturing a glass article and a glass article.

[0002] Semiconductors mounted on electronic devices have traditionally been required to have higher performance in response to the increasing amount of information processed. To achieve this, three-dimensional semiconductor packaging technology has emerged, namely, a technology for fabricating semiconductor packages by stacking semiconductor chips and connecting them via wiring. One well-known example of a semiconductor package is panel-level packaging (PLP). In PLP, rectangular support substrates are used to increase the number of semiconductor packages per support substrate while reducing manufacturing costs.

[0003] The manufacturing process of semiconductor packages involves heat treatment at approximately 200°C, which can cause the encapsulant to deform and warp the processed substrate due to differences in thermal expansion coefficients. If warping occurs in the processed substrate, it becomes difficult to achieve high-density wiring on one surface of the processed substrate and also makes it difficult to accurately form solder bumps.

[0004] Under these circumstances, in order to suppress warping due to the thermal expansion coefficients of the support substrate and the processing substrate, glass is used as the material for the support substrate (see, for example, Patent Document 1).

[0005] Glass substrates are easy to smooth the surface and have rigidity. Furthermore, by changing their composition, it is easy to match the thermal expansion coefficient with that of the surrounding substrate. Therefore, using a glass substrate as a support substrate makes it possible to firmly and accurately support the processed substrate. Furthermore, glass substrates are easily transparent to light, such as ultraviolet light and infrared light. Therefore, when a glass substrate is used as a support substrate, the processed substrate can be easily fixed by providing an adhesive layer, such as a UV-curable adhesive. Furthermore, the processed substrate can be easily separated by providing a peeling layer, such as an infrared-absorbing layer. Alternatively, the processed substrate can be easily fixed and separated by providing an adhesive layer, such as a UV-curable tape.

[0006] When a glass substrate is used as the support substrate in this manner, an identification mark may be formed on the glass substrate to manage and identify various information about the glass substrate (dimensions, thermal expansion coefficient, lot, overall thickness deviation, manufacturer name, and distributor name).

[0007] A known method for forming an identification symbol is to irradiate a glass substrate with a laser and then use the thermal shock that follows the irradiation to extend cracks (mainly cracks in the thickness direction) in the supporting glass substrate, thereby forming an information identification portion having the identification symbol.

[0008] However, in conventional forming processes using laser irradiation, glass components (mainly Si, B, Al, Li, Na, and K) are generated as fumes (evaporated materials), which solidify and accumulate on the surface around the heated area (information identification area) as debris (foreign matter). In particular, in forming processes using laser irradiation, fumes adhere to the glass surface in a highly energetic state, making it difficult to remove the debris. This can make it difficult to read the identification code. Furthermore, in the process of manufacturing semiconductor packages, unintended debris can contaminate the process. Furthermore, when thermal shock is used to propagate cracks in a supporting glass substrate to form an information identification area having an identification code, the unintended propagation of the cracks can reduce the strength of the supporting glass substrate.

[0009] Japanese Patent Application Laid-Open No. 2019-47106

[0010] The present invention has been made in consideration of the current problems, and aims to provide a method for manufacturing a glass article, and a glass article, which can reduce the energy of fumes generated when processing is performed by laser irradiation, thereby suppressing adhesion to the glass surface and facilitating debris removal, while also preventing a decrease in the strength of the supporting glass substrate due to cracks that develop during processing by laser irradiation.

[0011] The problem to be solved by the present invention is as described above, and the means for solving this problem will now be described.

[0012] A method for manufacturing a glass article according to Aspect 1 of the present invention is a method for manufacturing a glass article by laser processing using a pulsed laser, characterized in that the laser used in the laser processing has an output of 1 W or less and is performed by irradiating the line to be laser processed multiple times.

[0013] According to this configuration, the glass surface is processed by irradiating it multiple times with a power close to the lower limit value at which the glass can be processed, and the energy of the fumes generated during processing is reduced, thereby suppressing adhesion to the glass surface and facilitating removal of debris.

[0014] In the method for producing a glass article according to Aspect 2, in Aspect 1, it is preferable that the pulse laser is a femtosecond laser.

[0015] According to this configuration, the duration of each pulse irradiation can be shortened, thereby minimizing the thermal influence on the glass (such as damage due to thermal shock).

[0016] In the method for producing a glass article of Aspect 3, in Aspect 1 or 2, it is preferable that the product of the output, the reciprocal of the frequency (kHz) of the pulse laser, and the number of times the pulse laser is irradiated onto the planned laser processing line is 0.02 or more.

[0017] With this configuration, the energy irradiated to one point is kept within a certain range, so that the glass surface can be processed while reducing the energy of the fumes generated during processing, thereby suppressing adhesion to the glass surface and making it easier to remove debris.

[0018] In the method for producing a glass article according to Aspect 4, in any of Aspects 1 to 3, it is preferable that the number of times the pulse laser is irradiated onto the line to be laser processed is 2 to 10 times.

[0019] With this configuration, laser processing can be performed without setting the number of times of irradiation to the line to be laser processed more than necessary.

[0020] In the method for producing a glass article of Aspect 5, in Aspects 1 to 4, it is preferable that the line to be laser processed is repeatedly scanned from the start point to the end point, and irradiated a plurality of times.

[0021] With this configuration, the laser processing line can be processed efficiently.

[0022] In addition, in the method for producing a glass article of Aspect 6, in Aspects 1 to 5, the glass article contains, in mass %, B ２ O ３ and R ２ The total amount of O (R represents lithium, sodium and potassium) is preferably 5% or more.

[0023] B in glass ２ O ３ and R ２ O is a component that easily evaporates during laser processing (heating). ２ O ３ and R ２ In glasses containing 5% or more in total amount of O, the above-mentioned problems tend to become apparent, and the effects of aspects 1 to 5 can be enjoyed.

[0024] In addition, in the method for manufacturing a glass article of Aspect 7, in Aspects 1 to 6, it is preferable that the laser processing is processing to impart dots, and the dots are depressions formed from the surface of the glass article to the interior.

[0025] With this configuration, it is possible to obtain a highly visible identification information section.

[0026] In addition, in the method for manufacturing a glass article of Aspect 8, in Aspects 1 to 7, it is preferable that, in a cross-sectional view, the dot has an apex and a curved portion extending from the surface toward the interior, and has a plurality of inflection points between the surface and the apex.

[0027] With this configuration, the dots have a curved shape in cross section, which increases resistance to thermal shock and external forces and makes it easier to prevent cracks from extending from the dot surface to the supporting glass substrate.

[0028] In the method for producing a glass article of Aspect 9, in Aspects 1 to 8, it is preferable that the angle formed between the surface of the glass article and the peripheral edge of the dot is 130° or more in a cross-sectional view.

[0029] With this configuration, the angle formed between the surface of the glass article and the peripheral edge of the dot becomes gentle, which increases resistance to thermal shock and external force and makes it easier to suppress the extension of cracks from the dot surface to the supporting glass substrate.

[0030] In the method for producing a glass article of Aspect 10, in Aspects 1 to 9, it is preferable that the aspect ratio of the depth to the width of the dots in a cross-sectional view is 0.20 or more and 0.45 or less.

[0031] Such a configuration increases resistance to thermal shock and external force, and makes it easier to prevent cracks from extending from the dot surface to the supporting glass substrate.

[0032] In addition, in the method for producing a glass article of Aspect 11, in Aspects 1 to 10, it is preferable that the dots have laser processing marks on the inner surface, and the laser processing marks are formed in a stepped shape.

[0033] Such a configuration increases resistance to thermal shock and external force, and makes it easier to prevent cracks from extending from the dot surface to the supporting glass substrate.

[0034] In the method for producing a glass article of Aspect 12, in Aspects 1 to 11, it is preferable that the arithmetic mean roughness of the inner surfaces of the dots is 0.6 or less.

[0035] This configuration makes it easier to prevent cracks from starting from the irregularities on the inner surface of the dot and extending from the dot surface to the supporting glass substrate.

[0036] In the method for producing a glass article of Aspect 13, in Aspects 1 to 12, it is preferable that no evaporated material from the glass article adheres to the periphery of the dots.

[0037] This configuration makes it possible to improve the visibility of the dots.

[0038] In addition, in the method for manufacturing a glass article of Aspect 14, in Aspects 1 to 13, the method for setting the laser conditions preferably includes determining whether or not an evaporant from the glass article adheres to the surface of the glass article after completing N laser irradiations, and if no evaporant adheres, irradiating the glass article N+1 times or later to determine the state of laser processing, where N is a positive integer.

[0039] With this configuration, the next laser irradiation can be performed only after it is confirmed that no evaporants have adhered to the surface of the glass article, thereby preventing evaporants from adhering to the glass surface.

[0040] Furthermore, in the glass article of aspect 15, which is a glass article having dots formed thereon, it is preferable that the dots are depressions formed from the surface of the glass article to the interior in a cross-sectional view, have an apex and a curved portion extending from the surface to the interior, and have a plurality of inflection points between the surface and the apex.

[0041] With this configuration, it is possible to obtain a highly visible identification information section, and when viewed in cross section, the shape of the dot becomes curved, which increases resistance to thermal shock and external forces and makes it easier to suppress the extension of cracks from the dot surface to the supporting glass substrate.

[0042] In addition, in the glass article of Aspect 16, in Aspect 15, it is preferable that the angle formed between the surface of the glass article and the peripheral edge of the dot in a cross-sectional view is 130° or more.

[0043] With this configuration, the angle formed between the surface of the glass article and the peripheral edge of the dot is gentler, increasing resistance to thermal shock and external forces and making it easier to suppress the extension of cracks from the dot surface to the supporting glass substrate.

[0044] In addition, in the glass article of Aspect 17, in Aspect 15 or 16, it is preferable that the aspect ratio of the depth to the width of the dots in a cross-sectional view is 0.1 or more and 2 or less.

[0045] This configuration improves the visibility of the dots that form the identification information portion, and also makes it easier to prevent glass powder and the like from getting into the recesses of the dots.

[0046] In addition, in the glass article of Aspect 18, in any of Aspects 15 to 17, it is preferable that the dots have laser processing marks on the inner surface, and the laser processing marks are formed in a stepped shape.

[0047] This configuration is obtained by processing the glass by irradiating it with laser multiple times at a power close to the lower limit value at which glass can be processed, and as a result, it becomes easier to suppress the extension of cracks from the dot surface to the supporting glass substrate.

[0048] In the glass article of Aspect 19, in Aspects 15 to 18, the arithmetic mean roughness of the inner surfaces of the dots is preferably 0.6 or less.

[0049] With this configuration, it becomes easier to prevent cracks from starting from the irregularities in the surface roughness and extending from the dot surface to the supporting glass substrate.

[0050] In addition, in the glass article of Aspect 20, in Aspects 15 to 19, it is preferable that no evaporated material from the glass article adheres to the periphery of the dots.

[0051] With this configuration, it is possible to avoid a decrease in the visibility of the dots.

[0052] The present invention has the following effects.

[0053] According to the method for manufacturing a glass article of the present invention, by reducing the energy of fumes generated during processing by laser irradiation, adhesion to the glass surface can be suppressed, debris can be easily removed, and a decrease in the strength of the supporting glass substrate can be suppressed. Furthermore, according to the glass article of the present invention, adhesion to the glass surface can be suppressed, debris can be easily removed, and a decrease in the strength of the supporting glass substrate due to cracks that grow during processing by laser irradiation can be suppressed.

[0054] 1A to 1C are front cross-sectional views showing a process of processing a glass substrate using a pulsed laser according to one embodiment of the present invention; FIG. 1C is a schematic diagram showing a femtosecond laser pulse according to one embodiment of the present invention; FIG. 1D is a perspective view showing identification information processed on a glass substrate according to one embodiment of the present invention; FIG. 1E is a graph showing the relationship between output and frequency according to one embodiment of the present invention; FIG. 1A is a perspective view showing a glass substrate on which an annular groove has been formed by intermittently applying dots according to one embodiment of the present invention, and FIG. 1B is a cross-sectional view showing the glass substrate; FIG. 1D is an enlarged cross-sectional view showing a glass substrate on which dots have been applied according to one embodiment of the present invention, and an enlarged cross-sectional view of the dots.

[0055] Next, an embodiment of the present invention will be described. In each drawing referred to in the embodiment, components having substantially the same functions will be referred to by the same reference numerals. Furthermore, the drawings referred to in the embodiment are schematic.

[0056] Fig. 1 is a cross-sectional schematic diagram showing a step of laser processing using a pulsed laser 1 in a method for manufacturing a glass article according to this embodiment. As shown in Fig. 1, the glass article manufactured in this embodiment is a glass substrate G. Fig. 2 is a perspective view showing the glass substrate G on which an identification symbol (characters) is printed by laser processing.

[0057] 1 , the glass substrate G is a substrate suitable as a support substrate for a semiconductor package, and is a plate-like member having flatness and smoothness. In this embodiment, the glass article is constituted by the glass substrate G, but is not limited thereto and may be, for example, a thin glass plate such as a glass ribbon.

[0058] The glass used for the glass substrate G has a composition of, for example, SiO ２ 50 to 75%, Al ２ O ３ is 0-10%, B ２ O ３ is 0 to 20%, Li ２ O 0-5%, Na ２ O+K ２It is preferable that the glass contains 0 to 25% of O and 0 to 10% of MgO+CaO+SrO+BaO. With such a glass composition, it is easy to specify the thermal expansion coefficient within a target range and the devitrification resistance is improved, making it easy to produce a glass substrate G with a small deviation in the overall thickness.

[0059] Furthermore, the glass substrate G contains, in mass %, B ２ O ３ and R ２ The total amount of B in the glass is preferably 5% or more. ２ O ３ and R ２ O is a component that easily evaporates during laser processing (heating). ２ O ３ and R ２ Glass containing 5% or more in total amount of O is prone to generate fumes during laser processing (heating), and therefore the effects of the present invention can be enjoyed.

[0060] The glass substrate G of the present invention is preferably produced by preparing and mixing glass raw materials to prepare a glass batch, charging the glass batch into a glass melting furnace, fining and stirring the resulting molten glass, and then supplying it to a forming device and forming it into a plate shape.

[0061] The glass substrate G of the present invention is preferably formed by a downdraw method, particularly an overflow downdraw method. The overflow downdraw method is a method in which molten glass is allowed to overflow from both sides of a heat-resistant trough-shaped structure, and the overflowed molten glass is drawn downward while joining at the lower end of the trough-shaped structure to form a sheet. In the overflow downdraw method, the surface that will become the surface of the glass substrate G does not contact the trough-shaped refractory and is formed in a free surface state. Therefore, with a small amount of polishing, the overall thickness deviation can be reduced to less than 2.0 μm, particularly less than 1.0 μm. As a result, the manufacturing cost of the glass substrate G can be reduced.

[0062] The glass surface of the glass substrate G formed in this manner is subjected to laser processing. Laser processing is a process in which heat is applied to the surface of the glass substrate G by irradiating it with a laser, thereby melting the surface and forming dots T. As shown in Figure 2, the laser used for laser processing in this embodiment is an oscillation-type pulse laser 1. The pulse laser 1 is a laser whose optical output is composed of pulses P having a predetermined duration, and the pulses P are repeated at a predetermined frequency.

[0063] As shown in FIG. 3, it is preferable that the glass substrate G is fixed, and the pulse laser 1 is moved along a line L to be laser processed and irradiated intermittently to engrave the identification information C.

[0064] It is preferable to perform deeper processing by irradiating the same location with the pulsed laser 1 several times, as shown in Figure 1. For example, when irradiating the same location as shown in Figures 1(a) to 1(c), the first irradiation can be used to remove the outermost surface, the second irradiation can be used to deeply cut the processed portion, and the third irradiation can be used to finish the processed surface.

[0065] It is preferable to irradiate the pulsed laser 1 multiple times by repeatedly scanning from the start point to the end point of the line to be laser processed L. In other words, rather than irradiating the same location intermittently multiple times, it is preferable to finish irradiating the line to be laser processed L from the start point to the end point, and then start processing again from the start point of the line to be laser processed L. This makes it difficult for the glass substrate G to retain heat, and the energy of the fumes F generated can be reduced.

[0066] In this embodiment, it is preferable to use a femtosecond laser. The femtosecond laser has a pulse width Pd of 500 femtoseconds or less, and is a laser that can reduce the occurrence of cracks (cracks due to thermal shock) and debris D (substances melted or evaporated by the laser and attached to the surface) due to thermal effects. In other words, by shortening the duration of one pulse irradiation, the thermal effects on the glass substrate G can be kept low.

[0067] Next, the laser irradiation process for the line L to be laser processed in this embodiment and the laser irradiation process in the comparative example will be described with reference to Table 1 and FIG.

[0068] In the laser irradiation step, a pulsed laser 1 is used to apply a process for forming a series of dots T on the surface of the glass article, which is the target, to provide identification information C. As shown in Fig. 3, the identification information C is formed by engraving symbols containing information such as letters, numbers, and / or barcodes on the glass surface.

[0069] Furthermore, the output of the pulsed laser 1 is 1 W or less. By suppressing the output in this manner, the energy of the fumes F generated during processing is reduced. If the output of the pulsed laser 1 exceeds 1 W, the energy imparted to the glass substrate G by a single irradiation increases, and the depth of the dots T increases. However, a large amount of debris D having high energy due to excitation adheres to the surface of the glass substrate G at once. As a result, the debris D binds firmly to the surface of the glass substrate G, making it difficult to peel off. Peeling and removing the debris D requires removal by cutting, ultrasonic cleaning, and drying, which increases the cost of removal.

[0070] By setting the output of the pulse laser 1 to 1 W or less, it becomes possible to suppress adhesion of debris to the surface of the glass substrate G. In addition, the debris D can be easily removed.

[0071] Furthermore, it is preferable that the pulse laser 1 be irradiated onto the line L to be laser processed 4 to 6 times. By configuring in this way, the line L to be laser processed can be processed efficiently and the occurrence of smudges can be suppressed.

[0072] Furthermore, the product of the reciprocal of the frequency of the pulse laser 1, the output, and the number of irradiations is preferably 0.02 or more. The product increases as the number of irradiations increases, the frequency decreases, and the output increases. However, since the output is preferably 1 W or less, the product increases by decreasing the frequency or increasing the number of irradiations, and the specified conditions can be satisfied.

[0073] The output is the average output enclosed by the diagonal lines in Figure 4. The average output is calculated by taking the time average of the product of the pulse energy at the peak output enclosed by the lightly shaded area in Figure 4 and the repetition frequency. If the output is the same and the frequency increases, the pulse energy at the peak output weakens. Therefore, at lower frequencies, the pulse energy at the peak output is higher, and the average output required for processing decreases.

[0074] In addition, in the relationship between the laser output and the scanning speed on the line L to be laser processed, as the scanning speed increases, the irradiation time for one location becomes shorter, which reduces the amount of energy applied to the surface of the glass substrate G and increases the interval per scan.

[0075] Therefore, as the frequency increases, the energy of each pulse decreases and the number of times each spot is irradiated increases, while as the scanning speed increases, the energy of each pulse remains the same but the number of times each spot is irradiated decreases.

[0076] The product of the reciprocal of the frequency of the pulse laser 1, the output, and the number of irradiations is preferably 0.02 or more, which keeps the generation of debris D within an acceptable range. Suppressing the generation of debris D can prevent the occurrence of defective product quality. The presence of debris D may cause equipment contamination in the subsequent process of manufacturing a semiconductor package, making it more likely that defects will occur. Furthermore, if debris D adheres to the vicinity of the identification information C, it may cause errors in reading the identification information C.

[0077] In this way, by setting the product of the inverse of the frequency, the output, and the number of irradiations to 0.02 or more, it is possible to reliably process the line L to be laser processed while suppressing the generation of debris D.

[0078] 5 and 6, the dots T provided on the glass substrate G are formed in a recessed shape extending from the surface of the glass substrate G to the interior thereof. In a cross-sectional view, the dots T have an apex t1 and a curved portion t2 extending from the surface of the glass substrate G to the interior thereof, and have a plurality of inflection points between the surface of the glass substrate G and the apex t1.

[0079] As shown in FIG. 6 , the curvature angle at the inflection point connecting the surface of the glass substrate G and the first curved surface is θ1, the curvature angle at the inflection point connecting the first curved surface and the second curved surface is θ2, the curvature angle at the inflection point connecting the second curved surface and the third curved surface is θ3, the curvature angle at the inflection point connecting the third curved surface and the apex t1 is θ4, the curvature angle at the inflection point connecting the fourth curved surface and the fifth curved surface is θ5, the curvature angle at the inflection point connecting the fifth curved surface and the sixth curved surface is θ6, and the curvature angle at the inflection point connecting the sixth curved surface and the glass surface is θ7.

[0080] It is preferable that the curve angles θ1 and θ7 formed at the inflection points connecting the surface of the glass substrate G and the first curved surface, which is the peripheral edge of the dot T, are 130° or more.

[0081] Furthermore, the aspect ratio of the annular groove Tb of the dot T and the arithmetic mean roughness Ra, which is a parameter of the surface roughness, are preferably 0.6 or less. Here, the arithmetic mean roughness Ra is a numerical value obtained by adding the area of ​​the convex portions and the area of ​​the concave portions from the average surface and averaging the areas of the convex and concave portions, and dividing the sum by a reference length. By configuring in this way, the inner surface of the annular groove Tb of the dot T is configured smoothly, thereby suppressing the occurrence of cracks and debris D.

[0082] The aspect ratio 1 of the depth 1 to the width 1 of the annular groove Tb of the dot T is preferably 0.20 to 0.45, more preferably 0.20 to 0.30. Here, the aspect ratio is the ratio of the depth of the top t1 to the width of the annular groove Tb of the dot T in a cross-sectional view.

[0083] Furthermore, the aspect ratio 2 of the depth 2 to the width 2 is preferably 0.20 or more and 0.45 or less, more preferably 0.30 or more and 0.45 or less. When the aspect ratio 1 and the aspect ratio 2 are greater than 0.45, the depth to the apex t1 becomes relatively large and the curved portion t2 becomes steep. This often results in the occurrence of cracks (cracks due to thermal shock) and debris D (materials melted and evaporated by the laser that adhere to the surface).

[0084] The aspect ratio 1 of the depth 1 to the width 1 is preferably 0.20 or more and 0.45 or less, and the aspect ratio 2 of the depth 2 to the width 2 is 0.20 or more and 0.45 or less, so that the depth of the apex t1 is not large relative to the width of the annular groove Tb of the dot T. This results in the formation of the annular groove Tb of the dot T having a gently curved portion t2, which makes it possible to suppress the occurrence of cracks (breaks due to thermal shock).

[0085] Furthermore, as shown in the enlarged view of Figure 6, it is preferable that the dots T have laser processing marks Ta on their inner surfaces. The laser processing marks Ta are formed in a stepped shape. The laser processing marks Ta are formed in a stepped shape by multiple irradiations of the pulsed laser. By dividing the irradiation of the pulsed laser into multiple irradiations, it becomes difficult for the glass substrate G to retain heat, and the energy of the generated fumes F can be reduced. This makes it possible to prevent the fumes F, which are the evaporated parts of the glass article, from adhering to the periphery of the dots T.

[0086] [Examples] Table 1 shows the laser irradiation conditions for Examples 1 to 4 and Comparative Examples 1 and 2. In Table 1, "OK" indicates a good result, and "NG" indicates a bad result.

[0087] The glass articles used in the examples and comparative examples were substrate-shaped, and had a glass composition of, in mass %, SiO ２ 65%, Al ２ O ３ 5%, B ２ O ３ 15%, Li ２ O 2%, Na ２ O is 5%, K ２ A borosilicate glass containing 3% O, 3% MgO, and 2% CaO was used.

[0088] The evaluation items of whether or not debris was attached and whether there was any fading were visually confirmed at an illuminance of 10,000 Lx from a position 20 cm away from the surface of the glass substrate G (the surface processed by the pulse laser 1). The ease of removing debris D was also evaluated by visually checking the surface of the glass substrate G. Note that fading is an index related to the difficulty of reading (visibility) due to insufficient formation of the identification information C due to laser processing (heating).

[0089]

[0090] In Examples 1 to 4, the pulse laser 1 was a femtosecond laser, and the pulse width Pd was 400 femtoseconds.

[0091] In Examples 1 to 4, the frequency of the pulse laser 1 was 50 kHz. The output of the pulse laser 1 was 0.8 W to 1 W. By suppressing the output in this manner, the energy of the fumes F generated during processing was reduced, thereby making it possible to suppress adhesion of debris to the surface of the glass substrate G. Furthermore, the debris D was easily removed.

[0092] In addition, in Examples 1 to 4, the number of times that the pulse laser 1 was irradiated onto the line L to be laser processed was 4 to 6. By configuring in this manner, it was possible to efficiently process the line L to be laser processed, and the occurrence of smearing could be suppressed.

[0093] In Comparative Example 1, the frequency of the pulse laser 1 was 100 kHz. The output of the pulse laser 1 was 1.3 W. Therefore, in Comparative Example 1, the output and frequency were high, so that the energy given to the glass substrate G by one irradiation was large, and the depth of the dots T became deep.

[0094] In Comparative Example 1, the pulse laser 1 was irradiated onto the line L to be laser processed once.

[0095] In Comparative Example 2, the frequency of the pulse laser 1 was 100 kHz, and the output of the pulse laser 1 was 1.1 W.

[0096] In Comparative Example 2, the pulse laser 1 was irradiated onto the line L to be laser processed once.

[0097] In Examples 1 to 4, the product of the reciprocal of the frequency, the output, and the number of irradiations was 0.068 to 0.108.

[0098] In Examples 1 to 4, the occurrence of blurring was within the allowable range.

[0099] Furthermore, in Examples 1 to 4, the generation of debris D was within the allowable range.

[0100] As described above, the method for manufacturing a glass article in this embodiment is a method for manufacturing a glass article in which a pulse laser 1 is used to laser process the glass article, and the laser conditions used in the laser processing are an output of 1 W or less, and the laser processing is performed by irradiating the line L to be laser processed multiple times.This reduces the energy of the fumes F generated during processing, suppresses adhesion to the glass surface, and makes it easy to remove the debris D.

[0101] [Examples Regarding the Shape of Dots T] Table 2 shows Examples 5 and 6 and Comparative Example 3 with respect to the angle at the inflection point in the cross section of the annular groove Tb of the dots T formed by laser processing and the presence or absence of a curved portion.

[0102] The glass articles used in the examples and comparative examples were substrate-shaped, and had a glass composition of, in mass %, SiO ２ 65%, Al ２ O ３ 5%, B ２ O ３ 15%, Li ２ O 2%, Na ２ O is 5%, K ２ A borosilicate glass containing 3% O, 3% MgO, and 2% CaO was used.

[0103]

[0104] In Examples 5 and 6, the pulse laser 1 was a femtosecond laser with an output of 0.9 W and a pulse width Pd of 400 femtoseconds.

[0105] 5 and 6, the dots T provided on the glass substrate G were formed in a recessed shape extending from the surface of the glass substrate G to the interior thereof. In a cross-sectional view, the dots T had a top t1 and a curved portion t2 extending from the surface of the glass substrate G to the interior thereof, and had multiple inflection points between the surface of the glass substrate G and the top t1.

[0106] As shown in FIG. 6 , the curvature angle at the inflection point connecting the surface of the glass substrate G and the first curved surface is θ1, the curvature angle at the inflection point connecting the first curved surface and the second curved surface is θ2, the curvature angle at the inflection point connecting the second curved surface and the third curved surface is θ3, the curvature angle at the inflection point connecting the third curved surface and the apex t1 is θ4, the curvature angle at the inflection point connecting the fourth curved surface and the fifth curved surface is θ5, the curvature angle at the inflection point connecting the fifth curved surface and the sixth curved surface is θ6, and the curvature angle at the inflection point connecting the sixth curved surface and the glass surface is θ7.

[0107] In Examples 5 and 6, as shown in Table 2, the curvature angles θ1 and θ7 formed at the inflection points connecting the surface of the glass substrate G and the first curved surface, which is the peripheral edge of the dot T, were 130° or greater. On the other hand, in Comparative Example 3, the curvature angles θ1 and θ7 formed at the inflection points connecting the surface of the glass substrate G and the first curved surface, which is the peripheral edge of the dot T, were 124° or 119°. When θ1 and θ7 were smaller than 130°, the amount of deformation increased at the points where the peripheral edge of the dot T and the glass surface were connected, and cracks (cracks due to thermal shock) and debris D (material melted and evaporated by the laser and attached to the surface) were frequently observed. Therefore, it was shown that the angles θ1 and θ7 are preferably 130° or greater.

[0108] [Examples regarding the surface roughness and aspect ratio of the annular groove Tb of the dot T] Furthermore, Table 3 shows the aspect ratio and arithmetic mean roughness Ra, which is a parameter of the surface roughness, of the annular groove Tb of the dot T imparted by laser processing in this embodiment, for Examples 7 to 11 and Comparative Examples 4 to 6.

[0109]

[0110] Here, the aspect ratio is the ratio of the depth of the apex t1 to the width of the annular groove Tb of the dot T in a cross-sectional view. The arithmetic mean roughness Ra is a numerical value obtained by adding the area of ​​the convex portion and the area of ​​the concave portion from the average surface and dividing the sum by a reference length to average the areas of the convex and concave portions. In the case of the annular groove shown in Figure 5(a), the arithmetic mean roughness Ra was measured at the portion indicated by the circle M.

[0111] 5B, depth 1 is the depth of the portion where the depth D1 of the apex t1 is the smallest, and width 1 is the widthwise length W1 of the annular groove Tb of the dot T at depth D1. Depth 2 is the depth D2 of the portion where the depth of the apex t1 is the largest, and width 2 is the widthwise length W2 of the annular groove Tb of the dot T at depth D2. Note that in Examples 3 and 4, depth 2 was not measured, and therefore aspect ratio 2 was not calculated.

[0112] In Examples 7 to 11, the aspect ratio 1 of depth 1 to width 1 was 0.20 or more and 0.45 or less, more preferably 0.20 or more and 0.30 or less. In Examples 7 to 11, the aspect ratio 2 of depth 2 to width 2 was 0.20 or more and 0.45 or less, more preferably 0.30 or more and 0.45 or less.

[0113] In Comparative Examples 4 to 6, the aspect ratio 1 of the depth 1 to the width 1 was greater than 0.45. Also, in Comparative Examples 4 to 6, the aspect ratio 2 of the depth 2 to the width 2 was greater than 0.55. As a result, the depth to the apex t1 was relatively large, and the curved portion t2 was steep. As a result, the occurrence of cracks (cracks due to thermal shock) and debris D (material melted and evaporated by the laser and adhering to the surface) was frequently observed.

[0114] In Examples 7 to 11, the arithmetic mean roughness Ra was 0.6 or less.

[0115] Furthermore, the arithmetic mean roughness Ra was greater than 0.6 in Comparative Examples 4 to 6. This configuration resulted in irregularities on the inner surface of the dots T, and the occurrence of cracks (cracks caused by thermal shock) and debris D (substances melted and evaporated by the laser and adhering to the surface) was frequently observed.

[0116] The present invention can be used in a method for manufacturing a glass article and in a glass article.

[0117] 1 Pulse laser C Identification information D Debris F Fume G Glass substrate L Planned laser processing line T Dot t1 Top t2 Curved portion Ta Laser processing mark Tb Annular groove

Claims

1. A method for manufacturing a glass article by laser processing using a pulsed laser, wherein the laser used in the laser processing has an output of 1 W or less, and the line to be laser processed is irradiated multiple times to perform the laser processing.

2. The method for manufacturing a glass article according to claim 1, wherein the pulsed laser is a femtosecond laser.

3. A method for manufacturing a glass article as described in claim 1 or 2, wherein the product of the output, the reciprocal of the frequency (kHz) of the pulse laser, and the number of times the pulse laser is irradiated onto the line to be laser processed is 0.02 or more.

4. The method for manufacturing a glass article according to claim 1 or 2, wherein the pulsed laser is irradiated onto the line to be laser processed 2 to 10 times.

5. A method for manufacturing a glass article according to claim 1 or 2, in which the line to be laser processed is repeatedly scanned from the start point to the end point to irradiate multiple times.

6. The glass article contains, by mass%, B ２ O ３ and R ２ 3. The method for producing a glass article according to claim 1, wherein the total amount of O (R represents lithium, sodium and potassium) is 5% or more.

7. A method for manufacturing a glass article as described in claim 1 or 2, wherein the laser processing is a process for imparting dots, and the dots are depressions formed from the surface of the glass article to the inside.

8. A method for manufacturing a glass article as described in claim 1 or 2, wherein, in a cross-sectional view, the dot has an apex and a curved portion extending from the surface toward the inside, and has a plurality of inflection points between the surface and the apex.

9. A method for manufacturing a glass article as described in claim 1 or 2, wherein an angle formed between the surface of the glass article and the peripheral edge of the dot in a cross-sectional view is 130° or more.

10. A method for manufacturing a glass article as described in claim 1 or 2, wherein the aspect ratio of the depth to the width of the dots in a cross-sectional view is 0.20 or more and 0.45 or less.

11. The method for manufacturing a glass article according to claim 1 or 2, wherein the dots have laser processing marks on their inner surfaces, and the laser processing marks are formed in a stepped shape.

12. A method for manufacturing a glass article according to claim 1 or 2, wherein the arithmetic mean roughness of the inner surfaces of the dots is 0.6 or less.

13. A method for manufacturing a glass article as described in claim 1 or 2, wherein no evaporant from the glass article adheres to the periphery of the dots.

14. A method for manufacturing a glass article as described in claim 1 or 2, wherein the method for setting the laser conditions comprises determining whether or not there is any evaporant from the glass article adhering to the surface of the glass article after N rounds of laser irradiation, and irradiating the glass article for the N+1th time or later if no evaporant is adhering to the surface, to determine the state of the laser processing.

15. A glass article having dots formed thereon, wherein, in a cross-sectional view, the dots are depressions formed from the surface of the glass article toward the inside, have an apex and a curved portion extending from the surface toward the inside, and have a plurality of inflection points between the surface and the apex.

16. The glass article according to claim 15, wherein an angle formed between the surface of the glass article and the peripheral edge of the dot in a cross-sectional view is 130° or more.

17. A glass article as described in claim 15 or 16, wherein the aspect ratio of the depth to the width of the dots in a cross-sectional view is 0.1 or more and 2 or less.

18. The glass article according to claim 15 or 16, wherein the dots have laser processing marks on the inner surface, the laser processing marks being formed in a stepped shape.

19. The glass article according to claim 15 or 16, wherein the arithmetic mean roughness of the inner surfaces of the dots is 0.6 or less.

20. A glass article according to claim 15 or 16, wherein no evaporant from the glass article adheres to the periphery of the dots.

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