Supporting glass substrates and laminated substrates using them

Abstract

The present invention relates to a support glass substrate and a laminated substrate using the same. The support glass substrate is a support glass substrate for supporting a processed substrate. The support glass substrate is characterized in that it has an information identification part on its surface with points as structural units, and the average length of the cracks extending from the points in the surface direction is less than 350 μm.

Description

[0001] This application is a divisional application of PCT / JP2018 / 024617, application number 201880054592.1, application date 2018.6.28, invention title: “Supporting glass substrate and laminated substrate using the same”. Technical Field

[0002] The present invention relates to a support glass substrate for supporting a processing substrate and a laminated substrate using the same, and more particularly to a support glass substrate for supporting a processing substrate and a laminated substrate using the same in a semiconductor package (semiconductor device) manufacturing process. Background Technology

[0003] For portable electronic devices such as mobile phones, laptops, and PDAs (Personal Data Assistance), miniaturization and lightweighting are required. Consequently, the mounting space for semiconductor chips used in these devices is severely limited, making high-density semiconductor chip mounting a challenge. Therefore, in recent years, three-dimensional mounting technology has been developed, which involves stacking semiconductor chips on top of each other and connecting them with wiring to achieve high-density mounting of semiconductor packages.

[0004] Furthermore, conventional wafer-level packaging (WLP) involves forming bumps on a wafer and then dicing it to create a single wafer. However, conventional WLP makes it difficult to increase the pin count, and because it involves mounting the semiconductor chip with the back side exposed, it is prone to defects in the semiconductor chip.

[0005] Therefore, a fan-out type WLP was proposed as a new type of WLP. The fan-out type WLP can increase the number of pins, and in addition, by protecting the ends of the semiconductor chip, it can prevent damage to the semiconductor chip.

[0006] For fan-out type WLPs, there are pre-chip and post-chip manufacturing methods. In the pre-chip method, for example, there are steps such as molding multiple semiconductor chips with a resin sealing material to form a processing substrate, then wiring onto one surface of the processing substrate; and forming solder bumps. In the post-chip method, for example, there are steps such as setting a wiring layer on a support substrate, arranging multiple semiconductor chips, molding with a resin sealing material to form a processing substrate, and then forming solder bumps.

[0007] In addition, semiconductor packages known as panel-level packaging (PLP) are also being researched recently. In PLP, rectangular-shaped support substrates are used instead of wafer-shaped support substrates in order to increase the number of semiconductor packages obtained per support substrate and reduce manufacturing costs.

[0008] During the manufacturing process of these semiconductor packages, the sealing material may deform due to heat treatment at approximately 200°C, causing the substrate to warp. When the substrate warps, it becomes difficult to perform high-density wiring on one surface of the substrate, and it also becomes difficult to accurately form solder bumps.

[0009] In view of these circumstances, in order to suppress warping of the processing substrate, the use of a glass substrate for supporting the processing substrate is being studied (see Patent Document 1).

[0010] Glass substrates are easy to smooth and possess rigidity. Therefore, when using a glass substrate as a support substrate, the processed substrate can be firmly and accurately supported. Furthermore, glass substrates readily transmit ultraviolet and infrared light. Therefore, when using a glass substrate as a support substrate, the processed substrate can be easily fixed by providing an adhesive layer such as a UV-curable adhesive. Additionally, the processed substrate can be easily separated by providing a release layer that absorbs infrared light. Alternatively, by using an adhesive layer such as a UV-curable tape, the processed substrate can also be easily fixed and separated.

[0011] Existing technical documents

[0012] Patent documents

[0013] Patent Document 1: Japanese Patent Application Publication No. 2015-78113

[0014] Patent Document 2: International Publication No. 2016 / 136348 Summary of the Invention

[0015] The problem that the invention aims to solve

[0016] However, when a QR code information identification section (marking) is formed on the surface of the supporting glass substrate, production information of the supporting glass substrate (e.g., the dimensions of the glass substrate, coefficient of linear thermal expansion, batch number, overall thickness deviation, manufacturer's name, and seller's name) can be managed and identified. This information identification section is generally formed around the perimeter of the supporting glass substrate and is identified by the human eye in the form of text, symbols, etc. Furthermore, there are cases where the information identification section of the supporting glass substrate is automatically identified using optical elements such as CCD cameras. In such cases, the information identification section is required to be accurate even during automated processes.

[0017] As a method for forming an information recognition part, for example, it is known to irradiate a supporting glass substrate with a laser, and use the thermal shock before and after irradiation to cause cracks (mainly cracks in the thickness direction) to propagate in the supporting glass substrate, thereby forming an information recognition part (see Patent Document 2).

[0018] However, in the manufacturing process of fan-out type WLP and PLP, when the laminated substrate is heated to cure the resin for sealing material, the supporting glass substrate is prone to breakage when cooled to room temperature after the heated laminated substrate. This is due to the slight difference in the coefficient of thermal expansion between the processing substrate and the supporting glass substrate.

[0019] The present invention was made in view of the above circumstances, and its technical objective is to invent a support glass substrate that is not easily damaged during the manufacturing process of fan-out type WLP and PLP even when information recognition parts are formed on the surface.

[0020] Methods for solving problems

[0021] Through repeated experiments, the inventors discovered that by limiting the length of the crack originating from the point constituting the information recognition section to a predetermined value, the aforementioned technical problem can be solved, and thus this invention is proposed. Specifically, the supporting glass substrate of this invention is characterized by being a supporting glass substrate for supporting a processed substrate, having an information recognition section on its surface with points as structural units, and having a maximum length of the crack extending from the point in the surface direction of 350 μm or less. Here, "maximum length of the crack extending from the point in the surface direction" is the length measured along the shape of the crack when observed using an optical microscope, and not the length obtained by connecting the start and end points of the crack and measuring the distance between the two points, nor is it the length obtained by measuring the length of the crack in the thickness direction. It should be noted that the maximum length of the crack extending from the point in the surface direction can be controlled by the irradiation conditions of the pulsed laser (pulse width, irradiation diameter, irradiation speed, etc.).

[0022] Furthermore, it is preferable that the maximum length of the crack extending from a point in the surface direction of the supporting glass substrate of the present invention is 0.1 μm or more.

[0023] Furthermore, it is preferable that the dots on the supporting glass substrate of the present invention are formed by annular grooves. In this way, dots can be easily formed by laser ablation (based on the evaporation of glass caused by pulsed laser irradiation). As a result, when dots are formed by irradiation with a pulsed laser, by controlling the irradiation conditions, dots can be formed without causing excessive heat to accumulate in the irradiated area of ​​the glass.

[0024] Furthermore, in the supporting glass substrate of the present invention, it is preferable that the average linear thermal expansion coefficient is 30 × 10⁻⁶ in the temperature range of 30–380°C. -7 / ℃ or above and 165×10 -7 / ℃ or below. In this way, by changing the ratio of semiconductor chip to sealing material within the processing substrate, it is easy to precisely match the coefficients of thermal expansion of the processing substrate and the supporting glass substrate. Furthermore, when their coefficients of thermal expansion are matched, it is easier to suppress dimensional changes in the processing substrate during processing (especially warping). As a result, warping of the supporting glass substrate can be suppressed, and damage to the supporting glass substrate originating from cracks in the information recognition section of the supporting glass substrate can be reduced. Here, the "average linear coefficient of thermal expansion in the temperature range of 30 to 380°C" can be measured using a dilatometer.

[0025] Furthermore, the supporting glass substrate of the present invention preferably has a wafer shape or a generally circular plate shape with a diameter of 100 to 500 mm, a thickness of less than 2.0 mm, and an overall thickness deviation of less than 5 μm. Here, "overall thickness deviation" refers to the difference between the maximum and minimum thickness of the supporting glass substrate, which can be measured, for example, using an SBW-331ML / d measuring device manufactured by KOBELCO Research. "Warp" refers to the sum of the absolute value of the maximum distance between the highest point and the least squares focal plane of the supporting glass substrate, and the absolute value of the distance between the lowest point and the least squares focal plane, which can be measured, for example, using a Bow / Warp measuring device SBW-331ML / d manufactured by KOBELCO Research.

[0026] In addition, the supporting glass substrate of the present invention preferably has a quadrilateral shape with each side being 300 mm or more, a thickness of less than 2.0 mm, and an overall thickness deviation of less than 10 μm.

[0027] Furthermore, the laminated substrate of the present invention preferably includes at least a processing substrate and a support glass substrate for supporting the processing substrate, and the support glass substrate is the support glass substrate described above.

[0028] Furthermore, in the laminated substrate of the present invention, it is preferable that the substrate has at least a semiconductor chip molded with a sealing material.

[0029] The preferred method for manufacturing the semiconductor package of the present invention includes: a step of preparing a laminated substrate having at least a processing substrate and a support glass substrate for supporting the processing substrate; and a step of processing the processing substrate, wherein the support glass substrate is the aforementioned support glass substrate.

[0030] Furthermore, in the method for manufacturing the semiconductor package of the present invention, the processing preferably includes a step of wiring one surface of the processing substrate.

[0031] Furthermore, in the method for manufacturing the semiconductor package of the present invention, the processing preferably includes a step of forming solder bumps on one surface of a processing substrate.

[0032] The glass substrate of the present invention is characterized in that it has an information recognition part on its surface with points as structural units, and the maximum length of the crack extending from the point in the surface direction is less than 350 μm.

[0033] The following is for reference Figures 1-4 One embodiment of the present invention will be described. Figure 1 This is a plan view of a support glass substrate 1 according to one embodiment of the present invention. The support glass substrate 1 can be used to support a processed substrate. As shown in the figure, an information recognition portion 3 is formed on the surface 2 of the support glass substrate 1. In this embodiment, the support glass substrate 1 is generally circular. Furthermore, a notch 4 is provided as a positioning portion on the peripheral portion 1a of the support glass substrate 1, and the information recognition portion 3 is formed near the notch 4.

[0034] like Figure 2 As shown, the information recognition unit 3 includes, for example, multiple characters 5 (the characters 5 referred to herein are at least as follows). Figure 2 The combination includes ideographic characters such as numbers, as shown. Additionally, each character (5) is enlarged. Figure 2 As shown in section A, each part is composed of multiple points 6. Furthermore, taking the circumferential center position C3 of the notch 4 as a reference, the phase θ of the circumferential center position C4 of the information recognition unit 3 is... Figure 2 The setting is 2° or higher and 10° or lower.

[0035] Furthermore, point 6 will be explained. Figure 4 Zoom in Figure 3 Points 6, as shown in the diagram, are formed by ring-shaped grooves 7. Therefore, the points 6 constituting the character 5 are identified as ring-shaped. Figure 3 and Figure 4 In this embodiment, the groove 7 is annular. Furthermore, both the outer and inner periphery of the groove 7 are circular. Therefore, in this case, the width of the groove 7 remains constant throughout its entire circumference.

[0036] Crack 8 extends from the annular groove 7, but the maximum length of crack 8 in the surface direction is 0.5 to 10 μm. Attached Figure Description

[0037] Figure 1 This is a schematic top view illustrating an example of the supporting glass substrate of the present invention.

[0038] Figure 2 yes Figure 1 The enlarged view of the main part of the supporting glass substrate is shown.

[0039] Figure 3 yes Figure 2 An enlarged view of part A of the supporting glass substrate is shown.

[0040] Figure 4 yes Figure 3 An enlarged view of part B of the supporting glass substrate is shown.

[0041] Figure 5 This is a schematic perspective view showing an example of the laminated substrate of the present invention.

[0042] Figure 6 This is a schematic cross-sectional view showing the manufacturing process of a fan-out type WLP chip.

[0043] Figure 7 This is a microscope photograph of sample No. 2 involved in the embodiment.

[0044] Figure 8 This is a microscope photograph of sample No. 11 involved in the comparative example. Detailed Implementation

[0045] The supporting glass substrate of the present invention has an information recognition part on the surface of the supporting glass substrate, which uses points as structural units.

[0046] The information identification unit has one or more elements selected from text, symbols, QR codes, and graphics, and each element consists of multiple dots. Preferably, the information identification unit displays at least one piece of information selected from the dimensions of the supporting glass substrate, coefficient of linear thermal expansion, batch number, thickness deviation rate, manufacturer's name, seller's name, and material code. It should be noted that the term "dimension" as used herein is defined to include the thickness dimension, outer diameter dimension, and notch dimension of the supporting glass substrate.

[0047] In this invention, the maximum length of a crack extending from a point in the surface direction of the supporting glass substrate is 350 μm or less, preferably 300 μm or less, 250 μm or less, 0.1–180 μm, 0.3–100 μm, 0.3–50 μm, 0.5–30 μm, 0.5–20 μm, 0.8–10 μm, and particularly 1–5 μm. When the maximum length of the crack in the surface direction is too large, the supporting glass substrate is prone to breakage during the manufacturing process of fan-out type WLP and PLP. It should be noted that if the surface direction cracks generated from a point are completely eliminated, although the supporting glass substrate is less likely to break during the manufacturing process of fan-out type WLP and PLP, it is difficult to form a point in a short time by laser ablation, and the formation efficiency of the information recognition part is extremely reduced.

[0048] In the supporting glass substrate of the present invention, the maximum length of a crack propagating from a point in the thickness direction is preferably 200 μm or less, 100 μm or less, 50 μm or less, 30 μm or less, 20 μm or less, 10 μm or less, and particularly 5 μm or less. When the maximum length of the crack in the thickness direction is too large, the supporting glass substrate is prone to breakage during the manufacturing process of fan-out type WLP and PLP.

[0049] The outer diameter of the dot is preferably 0.05–0.20 mm, 0.07–0.13 mm or less, and particularly 0.09–0.11 mm. When the outer diameter of the dot is too small, the recognizability of the information recognition unit is easily reduced. On the other hand, when the outer diameter of the dot is too large, it is easier to ensure the strength of the supporting glass substrate.

[0050] The center-to-center distance between adjacent points is preferably 0.06 to 0.25 mm. When the center-to-center distance between adjacent points is too small, it is easy to ensure the strength of the supporting glass substrate. On the other hand, when the center-to-center distance between adjacent points is too large, the recognizability of the information recognition section is easily reduced.

[0051] The information recognition section can be formed using various methods. In this invention, it is preferable to form the information recognition section by irradiating it with a pulsed laser and ablating the glass in the irradiated area; in other words, the information recognition section is formed by laser ablation. In this way, ablation can be performed without excessive heat accumulating in the glass in the irradiated area. As a result, not only the length of cracks in the thickness direction can be reduced, but also the length of cracks propagating from a point in the surface direction can be reduced.

[0052] When using laser ablation to form the information recognition part, there are no particular restrictions on the laser irradiation conditions. For example, the pulse width of the pulsed laser can be set to the picosecond level, preferably the femtosecond level, specifically 10 fs or more and 500,000 fs (500 ps) or less. Furthermore, the wavelength of the pulsed laser is preferably 200 nm or more and 2500 nm or less, and its repetition frequency is preferably 1 Hz or more and 1 GHz or less. Additionally, the beam diameter of the pulsed laser is preferably 1 μm or more and 100 μm or less, and its scanning speed is preferably 1 mm / s or more and 800 mm / s or less. It should be noted that if the pulse width of the pulsed laser is too large, thermal strain is easily generated during laser irradiation.

[0053] The information recognition unit uses dots as structural units, and the shape of these dots is preferably annular grooves. In this way, when the dots are set as annular grooves, the area surrounded by the annular groove (the area further inward than the groove) is not removed by the laser and remains, thus minimizing the reduction in strength of the area where the information recognition unit is located. Furthermore, if the groove is annular, as long as the outer diameter is not changed, even if the width of the groove is reduced, the recognizability will not decrease significantly. Therefore, if the width is reduced without changing the outer diameter of the groove, the volume of the area further inward than the groove can be increased accordingly, thereby ensuring both recognizability and the required strength.

[0054] The depth of the groove forming the dots is preferably 2 to 30 μm. When the groove depth is too small, the recognizability of the information recognition part is easily reduced. On the other hand, when the groove depth is too large, it is easier to ensure the strength of the supporting glass substrate.

[0055] The Young's modulus of the supporting glass substrate is preferably 60 GPa or higher, 65 GPa or higher, 70 GPa or higher, and particularly 75–130 GPa. When the proportion of semiconductor chips in the processed substrate is small and the proportion of sealing material is large, the overall rigidity of the laminated substrate decreases, and the processed substrate is prone to warping during processing. Therefore, increasing the Young's modulus of the supporting glass substrate can easily reduce the warping of the processed substrate, thereby reducing the breakage of the supporting glass substrate in the information recognition section of the supporting glass substrate, which originates from cracks.

[0056] The coefficient of thermal expansion of the supporting glass substrate is preferably limited in a manner that matches the coefficient of thermal expansion of the processing substrate. Specifically, when the proportion of semiconductor chips in the processing substrate is small and the proportion of sealing material is large, it is preferable to increase the coefficient of thermal expansion of the supporting glass substrate; conversely, when the proportion of semiconductor chips in the processing substrate is large and the proportion of sealing material is small, it is preferable to decrease the coefficient of thermal expansion of the supporting glass substrate.

[0057] The average linear thermal expansion coefficient of the supporting glass substrate in the temperature range of 30–380°C is limited to 30 × 10⁻⁶. -7 / ℃ or higher and less than 50×10 -7At a given temperature, the glass composition preferably contains, by mass%, 55%–75% SiO2, 15%–30% Al2O3, 0.1%–6% Li2O, 0%–8% Na2O+K2O (total amount of Na2O and K2O), and 0%–10% MgO+CaO+SrO+BaO (total amount of MgO, CaO, SrO, and BaO). More preferably, it contains 55%–75% SiO2, 10%–30% Al2O3, 0%–0.3% Li2O+Na2O+K2O (total amount of Li2O, Na2O, and K2O), and 5%–20% MgO+CaO+SrO+BaO. Even more preferably, it contains 55%–68% SiO2, 12%–25% Al2O3, 0%–15% B2O3, and MgO+CaO+SrO+BaO. The composition is 5%–30%, and preferably contains, by mass%, 65%–75% SiO2, 1%–10% Al2O3, 10%–20% B2O3, 0%–3% Li2O, 3%–9% Na2O+K2O, and 0%–5% MgO+CaO+SrO+BaO. The average linear thermal expansion coefficient of the supporting glass substrate is limited to 50 × 10⁻⁶ C⁻¹ in the temperature range of 30–380°C. -7 / ℃ or higher and less than 70×10 -7 At a given temperature, the glass composition preferably contains, by mass%, 55%–75% SiO2, 3%–15% Al2O3, 5%–20% B2O3, 0%–5% MgO, 0%–10% CaO, 0%–5% SrO, 0%–5% BaO, 0%–5% ZnO, 0%–5% Na2O, and 0%–10% K2O. More preferably, it contains 64%–71% SiO2, 5%–10% Al2O3, 8%–15% B2O3, 0%–5% MgO, 0%–6% CaO, 0%–3% SrO, 0%–3% BaO, 0%–3% ZnO, 5%–15% Na2O, and 0%–5% K2O. The average linear thermal expansion coefficient of the supporting glass substrate in the temperature range of 30–380°C is limited to 70 × 10⁻⁶. -7 / ℃ or above and 85×10 -7When the temperature is below a certain value, the glass composition preferably contains, by mass%, 60%–75% SiO2, 5%–15% Al2O3, 5%–20% B2O3, 0%–5% MgO, 0%–10% CaO, 0%–5% SrO, 0%–5% BaO, 0%–5% ZnO, 7%–16% Na2O, and 0%–8% K2O. More preferably, it contains 60%–68% SiO2, 5%–15% Al2O3, 5%–20% B2O3, 0%–5% MgO, 0%–10% CaO, 0%–3% SrO, 0%–3% BaO, 0%–3% ZnO, 8%–16% Na2O, and 0%–3% K2O. The average linear thermal expansion coefficient of the supporting glass substrate in the temperature range of 30–380°C is limited to 70 × 10⁻⁶. -7 / ℃ or above and 85×10 -7 When the temperature is below a certain range, the glass composition preferably contains, by mass%, 10%–60% SiO2, 0%–8% Al2O3, 0%–20% B2O3, 10%–40% BaO, and 3%–30% TiO2 + La2O3. The average linear thermal expansion coefficient of the supporting glass substrate is limited to 50 × 10⁻⁶ °C in the temperature range of 30–380 °C. -7 / ℃ or above and 85×10 -7 When the temperature is below a certain value, the glass composition preferably contains, by mass%, 45%–65% SiO2, 0%–15% Al2O3, 0%–20% B2O3, 0%–3% MgO, 1%–20% CaO, 0%–20% SrO, 0%–30% BaO, 0%–5% ZnO, 0%–10% ZrO2, 0%–20% TiO2, 0%–20% Nb2O5, 0%–30% La2O3, 0%–5% Na2O, and 0%–10% K2O. More preferably, it contains 45%–60% SiO2, 6%–13% Al2O3, 0%–5% B2O3, 0%–3% MgO, 1%–5% CaO, 10%–20% SrO, and 15%–30% BaO. Furthermore, it is even more preferable to contain 20%–60% SiO2, 0%–20% B2O3, 3%–20% CaO, 0%–3% SrO, 5%–20% BaO, 0%–10% ZrO2, 0%–20% TiO2, 0%–20% Nb2O5, 0%–30% La2O3, 0%–5% Na2O, and 0%–10% K2O. The average linear thermal expansion coefficient of the supporting glass substrate in the temperature range of 30–380°C is limited to more than 85 × 10⁻⁶. -7 / ℃ and is 120×10 -7When the temperature is below a certain threshold, the glass composition preferably contains, by mass%, 55%–70% SiO2, 3%–13% Al2O3, 2%–8% B2O3, 0%–5% MgO, 0%–10% CaO, 0%–5% SrO, 0%–5% BaO, 0%–5% ZnO, 10%–21% Na2O, and 0%–5% K2O. The average linear thermal expansion coefficient of the supporting glass substrate in the temperature range of 30–380°C is limited to more than 120 × 10⁻⁶. -7 / ℃ and is 165×10 -7 For temperatures below a certain temperature, the preferred glass composition, by mass%, comprises: 53%–65% SiO2, 3%–13% Al2O3, 0%–5% B2O3, 0.1%–6% MgO, 0%–10% CaO, 0%–5% SrO, 0%–5% BaO, 0%–5% ZnO, 20%–40% Na2O+K2O, 12%–21% Na2O, and 7%–21% K2O. This composition facilitates limiting the coefficient of thermal expansion to within the target range and improves devitrification resistance, thus making it easier to manufacture support glass substrates with minimal overall thickness variation.

[0058] The liquid phase temperature of the supporting glass substrate is preferably below 1150°C, specifically below 1120°C, 1100°C, 1080°C, 1050°C, 1010°C, 980°C, 960°C, 950°C, and particularly below 940°C. Furthermore, the liquid phase viscosity of the supporting glass substrate is preferably 10. 4.8 dPa·s or more, 10 5.0 dPa·s or more, 10 5. 2 dPa·s or higher, 10 5.4 dPa·s and above, especially 10 5.6 Above dPa·s. In this way, it is easy to form a plate using the pull-down method, especially the overflow pull-down method, thus reducing the overall plate thickness deviation even without surface grinding. Alternatively, with minimal grinding, the overall plate thickness deviation can be reduced to less than 2.0 μm, especially less than 1.0 μm. As a result, the manufacturing cost of the supporting glass substrate can also be reduced. It should be noted that the "liquid phase temperature" can be calculated as follows: glass powder that has passed through a standard sieve of 30 mesh (500 μm) and has residues at 50 mesh (300 μm) is placed in a platinum boat, held in a temperature gradient furnace for 24 hours, and the temperature at which crystallization occurs is measured. The "liquid phase viscosity" can be calculated by measuring the viscosity of the glass at the liquid phase temperature using the platinum ball pulling method.

[0059] The supporting glass substrate of the present invention preferably has the following shape.

[0060] The supporting glass substrate of the present invention is preferably wafer-shaped or substantially circular, with a diameter preferably between 100 mm and 500 mm, particularly between 150 mm and 450 mm. This facilitates its application in the manufacturing process of fan-out type WLPs. Furthermore, the supporting glass substrate of the present invention is preferably quadrilateral (particularly rectangular), with the length of each side preferably between 300 mm and 600 mm, 400 mm and 550 mm, 415 mm and 515 mm, particularly between 450 mm and 510 mm. This facilitates its application in the manufacturing process of fan-out type PLPs.

[0061] In the supporting glass substrate of the present invention, the thickness is preferably less than 2.0 mm, and is 1.8 mm or less, 1.6 mm or less, 1.5 mm or less, 1.2 mm or less, 1.1 mm or less, 1.0 mm or less, and particularly 0.9 mm or less. The thinner the thickness, the lighter the mass of the laminated substrate, thus improving operability. On the other hand, when the thickness is too thin, the strength of the supporting glass substrate itself decreases, making it difficult to fulfill its function as a supporting substrate. Therefore, the thickness is preferably 0.1 mm or more, 0.2 mm or more, 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, 0.6 mm or more, and particularly more than 0.7 mm.

[0062] In the supporting glass substrate of the present invention, the overall thickness deviation is preferably 10 μm or less, 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, 1 μm or less, and particularly 0.1 μm or more but less than 1 μm. Furthermore, the arithmetic mean roughness Ra is preferably 20 nm or less, 10 nm or less, 5 nm or less, 2 nm or less, 1 nm or less, and particularly 0.5 nm or less. Higher surface accuracy makes it easier to improve processing precision. In particular, it improves wiring accuracy, thus enabling high-density wiring. Additionally, the strength of the supporting glass substrate is increased, making the supporting glass substrate and the laminated substrate less prone to breakage. This further increases the number of times the supporting glass substrate can be reused. It should be noted that the "arithmetic mean roughness Ra" can be measured using a stylus-type surface roughness meter or an atomic force microscope (AFM).

[0063] In the supporting glass substrate of the present invention, the warpage is preferably 60 μm or less, 55 μm or less, 50 μm or less, 1 to 45 μm, and particularly 5 to 40 μm. The smaller the warpage, the easier it is to improve the processing accuracy. In particular, it can improve the wiring accuracy, thus enabling high-density wiring.

[0064] In the supporting glass substrate of the present invention, the roundness is preferably 1 mm or less, 0.1 mm or less, 0.05 mm or less, and particularly 0.03 mm or less. The smaller the roundness, the easier it is to apply to the manufacturing process of fan-out type WLP and PLP. It should be noted that "roundness" is the value of the maximum value minus the minimum value of the outer shape, excluding the notch.

[0065] The supporting glass substrate of the present invention preferably has a notch, and the deeper part of the notch is more preferably generally circular or generally V-groove shaped when viewed from above. This allows the supporting glass substrate to be easily fixed in position by abutting a positioning member such as a positioning pin against the notch. As a result, alignment of the supporting glass substrate and the processing substrate is easy. In particular, if a notch is also formed on the processing substrate, alignment of the entire stacked substrate is easy when the positioning member abuts against it. It should be noted that the notch abuts against the positioning member, thus making it prone to cracking. The supporting glass substrate of the present invention has high crack resistance, making it particularly effective in cases where a notch is present.

[0066] When the notch of the supporting glass substrate abuts against the positioning member, stress tends to concentrate at the notch, making the supporting glass substrate prone to breakage starting from the notch. This tendency becomes particularly pronounced when the supporting glass substrate is bent by external force. Therefore, in the supporting glass substrate of the present invention, all or part of the edge region where the surface of the notch intersects with the end face is chamfered. This effectively avoids breakage starting from the notch.

[0067] In this invention, all or part of the edge region where the surface of the notch intersects the end face of the supporting glass substrate is chamfered. Preferably, more than 50% of the edge region where the surface of the notch intersects the end face is chamfered, more preferably more than 90% of the edge region where the surface of the notch intersects the end face is chamfered, and even more preferably, the entire edge region where the surface of the notch intersects the end face is chamfered. The larger the chamfered area in the notch, the lower the probability of breakage starting from the notch.

[0068] The chamfer width in the surface direction of the notch is preferably 50–900 μm, 200–800 μm, 300–700 μm, 400–650 μm, and especially 500–600 μm. If the chamfer width in the surface direction of the notch is too small, the supporting glass substrate is prone to breakage starting from the notch. On the other hand, if the chamfer width in the surface direction of the notch is too large, the chamfering efficiency decreases, and the manufacturing cost of the supporting glass substrate tends to increase.

[0069] The chamfer width in the thickness direction of the notch is preferably 5%–80%, 20%–75%, 30%–70%, 35%–65%, and particularly 40%–60% of the plate thickness. If the chamfer width in the thickness direction of the notch is too small, the supporting glass substrate is prone to breakage starting from the notch. On the other hand, if the chamfer width in the thickness direction of the notch is too large, the external force tends to concentrate on the end face of the notch, and the supporting glass substrate is prone to breakage starting from the end face of the notch.

[0070] The supporting glass substrate of the present invention is preferably prepared by mixing glass raw materials to make a glass batch. After the glass batch is put into a glass melting furnace, the resulting molten glass is clarified and stirred, and then fed to a forming device to be formed into a plate shape for manufacturing.

[0071] The supporting glass substrate of the present invention is preferably formed by a down-drawing method, particularly an overflow down-drawing method. The overflow down-drawing method involves allowing molten glass to overflow from both sides of a heat-resistant, channel-like structure, while simultaneously allowing the overflowing molten glass to converge at the lower top of the channel-like structure, and extending downwards to form a plate shape. In the overflow down-drawing method, the surface of the supporting glass substrate should not contact the channel-like refractory, forming it in a free-surface state. Therefore, with minimal grinding, the overall plate 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 supporting glass substrate can be reduced.

[0072] The supporting glass substrate of the present invention is preferably formed by an overflow pull-down method and then the surface is ground. In this way, it is easy to limit the overall thickness deviation to less than 2.0 μm, less than 1.5 μm, less than 1.0 μm, and especially more than 0.1 μm but less than 1.0 μm.

[0073] The supporting glass substrate of the present invention is preferably not subjected to ion exchange treatment, and preferably does not have a compressive stress layer on its surface. If ion exchange treatment is performed, it is difficult to reduce the overall thickness deviation of the supporting glass substrate; however, if ion exchange treatment is not performed, this defect can be eliminated. It should be noted that the supporting glass substrate of the present invention does not exclude the option of performing ion exchange treatment and forming a compressive stress layer on the surface. When only considering improving mechanical strength, ion exchange treatment and forming a compressive stress layer on the surface are preferred.

[0074] The laminated substrate of the present invention is characterized by comprising at least a processing substrate and a supporting glass substrate for supporting the processing substrate, wherein the supporting glass substrate is the aforementioned supporting glass substrate. Preferably, the laminated substrate of the present invention has an adhesive layer between the processing substrate and the supporting glass substrate. The adhesive layer is preferably a resin, such as a thermosetting resin, a photocurable resin (especially an ultraviolet-curable resin), etc. Furthermore, it preferably has heat resistance capable of withstanding heat treatment during the manufacturing process of fan-out type WLPs and PLPs. Therefore, the adhesive layer is less likely to melt during the manufacturing process of fan-out type WLPs and PLPs, improving the accuracy of the processing. It should be noted that, in order to easily fix the processing substrate and the supporting glass substrate, ultraviolet-curable tape may also be used as an adhesive layer.

[0075] The laminated substrate of the present invention preferably further comprises a release layer between the processing substrate and the supporting glass substrate, more specifically between the processing substrate and the adhesive layer, or between the supporting glass substrate and the adhesive layer. In this way, after the processing substrate undergoes a prescribed processing treatment, it can be easily peeled off from the supporting glass substrate. From a production point of view, the peeling of the processing substrate is preferably performed by irradiation with light such as a laser. As the laser source, infrared laser sources such as YAG lasers (wavelength 1064 nm) and semiconductor lasers (wavelength 780–1300 nm) can be used. Alternatively, a resin that decomposes upon irradiation with an infrared laser can be used as the release layer. Furthermore, substances that efficiently absorb infrared radiation and convert it into heat can be added to the resin. For example, carbon black, graphite powder, particulate metal powder, dyes, pigments, etc., can also be added to the resin.

[0076] The release layer is composed of a material that undergoes "intra-layer peeling" or "interfacial peeling" when irradiated with light such as a laser. In other words, it is composed of a material whose interatomic or intermolecular bonds disappear or decrease when irradiated with light of a certain intensity, resulting in ablation and subsequent peeling. It should be noted that there are cases where the components contained in the release layer become gaseous and are released and separated due to irradiation with light, and cases where the release layer absorbs light, becomes gaseous, and releases its vapor, leading to separation.

[0077] In the laminated substrate of the present invention, it is preferable that the supporting glass substrate is larger than the processing substrate. Therefore, when the processing substrate and the supporting glass substrate are supported, even if their center positions are slightly offset, the edge of the processing substrate is less likely to protrude from the supporting glass substrate.

[0078] The method for manufacturing a semiconductor package of the present invention is characterized by comprising: a step of preparing a laminated substrate having at least a processing substrate and a support glass substrate for supporting the processing substrate; and a step of processing the processing substrate, wherein the support glass substrate is the aforementioned support glass substrate.

[0079] The method for manufacturing the semiconductor package of the present invention preferably further includes a step of conveying a multilayer substrate. This improves processing efficiency. It should be noted that the "step of conveying the multilayer substrate" and the "step of processing the substrate" do not need to be performed separately and can be performed simultaneously.

[0080] In the semiconductor package manufacturing method of the present invention, the preferred processing steps are wiring on one surface of the processing substrate or forming solder bumps on one surface of the processing substrate. In these processing steps, the processing substrate is less prone to dimensional changes, thus these steps can be performed appropriately.

[0081] In addition to the above-described processing methods, any of the following processing methods may also be used: mechanically grinding one surface of the substrate (typically the surface opposite to the supporting glass substrate), dry etching one surface of the substrate (typically the surface opposite to the supporting glass substrate), or wet etching one surface of the substrate (typically the surface opposite to the supporting glass substrate). It should be noted that in the semiconductor package manufacturing method of the present invention, warping is less likely to occur in the processed substrate, and the rigidity of the stacked substrate can be maintained. As a result, the above-described processing methods can be appropriately performed.

[0082] The present invention will be further described with reference to the accompanying drawings. Figure 5 This is a schematic perspective view showing an example of the laminated substrate 9 of the present invention. Figure 5 In this laminated substrate 9, there are a supporting glass substrate 10 and a processing substrate 11. To prevent dimensional changes in the processing substrate 11, the supporting glass substrate 10 is attached to the processing substrate 11. A release layer 12 and an adhesive layer 13 are disposed between the supporting glass substrate 10 and the processing substrate 11. The release layer 12 is in contact with the supporting glass substrate 10, and the adhesive layer 13 is in contact with the processing substrate 11.

[0083] As by Figure 5 It can be seen that the laminated substrate 9 sequentially comprises a supporting glass substrate 10, a release layer 12, an adhesive layer 13, and a processing substrate 11. The shape of the supporting glass substrate 10 is determined based on the processing substrate 11. Figure 1In this design, both the supporting glass substrate 10 and the processing substrate 11 are approximately circular. The release layer 12 can be, for example, a resin that decomposes upon laser irradiation. Alternatively, a substance that efficiently absorbs laser light and converts it into heat can be added to the resin. Examples include carbon black, graphite powder, particulate metal powder, dyes, and pigments. The release layer 12 is formed by plasma CVD or a spin coating method based on the sol-gel process. The adhesive layer 13 is composed of resin and is formed, for example, by coating using various printing, inkjet, spin coating, or roll coating methods. Alternatively, a UV-curable adhesive tape can be used. After the supporting glass substrate 10 is peeled from the processing substrate 11 by the release layer 12, the adhesive layer 13 is dissolved and removed by a solvent or the like. The UV-curable adhesive tape can be removed by the release tape after irradiation with ultraviolet light.

[0084] Figure 6 This is a schematic cross-sectional view showing the manufacturing process of a fan-out type WLP chip. Figure 6 (a) shows the state in which the adhesive layer 21 is formed on one surface of the support member 20. If necessary, a release layer may also be formed between the support member 20 and the adhesive layer 21. Next, as... Figure 6 As shown in (b), a plurality of semiconductor chips 22 are attached to the adhesive layer 21. At this time, the active side of the semiconductor chip 22 is brought into contact with the adhesive layer 21. Next, as... Figure 6 As shown in (c), the semiconductor chip 22 is molded using a resin sealing material 23. The sealing material 23 is made of a material with minimal dimensional change after compression molding and minimal dimensional change during wiring. Next, as... Figure 6 As shown in (d) and (e), after the processing substrate 24 on which the semiconductor chip 22 is molded is separated from the support member 20, it is bonded and fixed to the support glass substrate 26 by means of the adhesive layer 25. At this time, the surface of the processing substrate 24 opposite to the surface on which the semiconductor chip 22 is embedded is disposed on the support glass substrate 26 side. In this way, a laminated substrate 27 can be obtained. It should be noted that, if necessary, a release layer may also be formed between the adhesive layer 25 and the support glass substrate 26. Furthermore, after the obtained laminated substrate 27 is transported, as... Figure 6 As shown in (f), after forming wiring 28 on the surface of the processing substrate 24 on the side where the semiconductor chip 22 is embedded, a plurality of solder bumps 29 are formed. Finally, after separating the processing substrate 24 from the supporting glass substrate 26, the processing substrate 24 is cut into individual semiconductor chips 22 and then supplied to subsequent packaging processes. Figure 6 (g)).

[0085] The glass substrate of the present invention is characterized in that it has an information recognition portion on its surface with points as structural units, and the maximum length of a crack extending from a point in the surface direction is less than 350 μm. It should be noted that the technical features of the glass substrate of the present invention have already been described in the description of the supporting glass substrate of the present invention, and detailed descriptions are omitted here.

[0086] Example

[0087] The present invention will now be described based on embodiments. It should be noted that the following embodiments are merely illustrative. The present invention is not limited to the following embodiments.

[0088] Table 1 shows the embodiments (samples No. 1 to 10) and comparative examples (sample No. 11) of the present invention.

[0089] [Table 1]

[0090] No.1 No.2 No.3 No. 4 No. 5 No. 6 No. 7 No. 8 No. 9 No. 10 No. 11 <![CDATA[Linear coefficient of thermal expansion (×10 -7 / °C)]]> 35 58 75 91 70 48 95 102 112 102 102 Maximum crack length (μm) 4 9 8 196 1 5 35 97 45 85 352 Process damage ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ×

[0091] The glass substrate for Sample No. 1 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained SiO2 59.7%, Al2O3 16.5%, B2O3 10.3%, MgO 0.3%, CaO 8.0%, SrO 4.5%, BaO 0.5%, and SnO2 0.2% by mass. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1550°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the obtained glass substrate was cut into a rectangular shape.

[0092] The glass substrate for Sample No. 2 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 66.1% SiO2, 8.5% Al2O3, 12.4% B2O3, 8.4% Na2O, 3.3% CaO, 0.9% ZnO, and 0.4% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1500°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0093] The glass substrate for sample No. 3 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 65.8% SiO2, 8.0% Al2O3, 8.9% B2O3, 12.8% Na2O, 3.2% CaO, 0.9% ZnO, and 0.4% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1500°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0094] The glass substrate for sample No. 4 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 61.6% SiO2, 18.0% Al2O3, 0.5% B2O3, 14.5% Na2O, 2.0% K2O, 3.0% MgO, and 0.4% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1650°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0095] The glass substrate for sample No. 5 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained, by mass %: SiO2 40.92%, Al2O3 5.0%, B2O3 5.0%, CaO 3.0%, SrO 11.2%, BaO 25.2%, ZnO 3.0%, TiO2 4.6%, ZrO2 2.0%, and Sb2O3 0.08%. The resulting glass batch was then fed into a glass melting furnace and melted at 1250°C. The resulting molten glass was then clarified and stirred before being fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Finally, the resulting glass substrate was cut into a rectangular shape.

[0096] The glass substrate for sample No. 6 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 72.75% SiO2, 4.3% Al2O3, 15.1% B2O3, 5.7% Na2O, 1.8% K2O, 0.2% CaO, and 0.15% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1600°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0097] The glass substrate for sample No. 7 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 65.8% SiO2, 8.0% Al2O3, 3.7% B2O3, 18.1% Na2O, 3.2% CaO, 0.9% ZnO, and 0.3% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1300°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0098] The glass substrate for sample No. 8 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 65.7% SiO2, 8.0% Al2O3, 2.1% B2O3, 19.8% Na2O, 3.2% CaO, 0.9% ZnO, and 0.3% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1300°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0099] The glass substrate for sample No. 9 was prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 65.3% SiO2, 8.0% Al2O3, 22.3% Na2O, 3.2% CaO, 0.9% ZnO, and 0.3% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1300°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrate was cut into a rectangular shape.

[0100] Glass substrates for samples No. 10 and 11 were prepared as follows: First, glass raw materials were prepared and mixed according to the following formula, which contained 65.7% SiO2, 8.0% Al2O3, 2.1% B2O3, 19.8% Na2O, 3.2% CaO, 0.9% ZnO, and 0.3% SnO2 by mass percentage. After obtaining the glass batch, it was fed into a glass melting furnace and melted at 1650°C. Next, the resulting molten glass was clarified and stirred, and then fed into an overflow-draw forming apparatus to form a plate with a thickness of 1.05 mm. Then, the resulting glass substrates were cut into rectangular shapes.

[0101] Next, the cut glass substrates (samples No. 1-11: overall thickness deviation approximately 4.0 μm) were excavated to a diameter of 300 mm, and then both surfaces of the glass substrates were ground using a grinding device. Specifically, a pair of grinding pads with different outer diameters were clamped between the two surfaces of the glass substrate, and the glass substrate and the pair of grinding pads were rotated together while grinding the two surfaces of the glass substrate. During the grinding process, the process was occasionally controlled so that a portion of the glass substrate protruded from the grinding pads. It should be noted that the grinding pads were made of polyurethane, the average particle size of the grinding slurry used during the grinding process was set to 2.5 μm, and the grinding speed was set to 15 m / min. For each glass substrate that had undergone grinding, the overall thickness deviation and warpage were measured using a Bow / Warp measuring device SBW-331ML / d manufactured by KOBELCO Research Corporation. The results showed that the overall thickness deviation was less than 1.0 μm and the warpage was less than 35 μm. For each glass substrate that had undergone grinding, the average linear thermal expansion coefficient was measured using a dilatometer in the temperature range of 30–380 °C. The results are shown in Table 1.

[0102] For the polished glass substrate, a pulsed femtosecond laser was used to set multiple points, each consisting of annular grooves, as information recognition units for structural elements. Here, for samples No. 1 to 11, the maximum length of the crack propagating from the point was controlled by adjusting the pulse width of the pulsed femtosecond laser. Next, the maximum length of the crack originating from the point was measured using a VHX-600 digital microscope (manufactured by KEYENCE). The results are shown in Table 1. Figure 7 , Figure 8 . Figure 7 This is a microscope photograph of sample No. 2. Figure 8 This is a microscope photograph of sample No. 11. It should be noted that the maximum length of the crack was obtained by depicting the crack and measuring its length using length measurement software.

[0103] For the glass substrate with the information recognition part formed, heat treatment is performed to simulate the manufacturing process of fan-out type WLP and PLP. The case where the glass substrate is not broken is marked as "○" and the case where the glass substrate is broken due to cracks generated from a point is marked as "×".

[0104] As shown in Table 1, the maximum length of the crack originating from point 1 to point 10 in the surface direction is small, therefore it can be considered that breakage is unlikely to occur during the manufacturing process of fan-out type WLP and PLP. On the other hand, the maximum length of the crack originating from point 11 in the surface direction is large, therefore it can be considered that breakage is likely to occur during the manufacturing process of fan-out type WLP and PLP.

[0105] Explanation of reference numerals in the attached figures

[0106] 1, 10, 26 support glass substrate

[0107] 1a Peripheral part

[0108] 2 Surface

[0109] 2a, 2b divide the region

[0110] 3. Information Identification Department

[0111] 4. Notch

[0112] 5 text

[0113] 6 o'clock

[0114] 7. Circular trench

[0115] 8 Cracks

[0116] 9, 27 layers

[0117] 11, 24 Processing substrate

[0118] 12. Peel-off layer

[0119] 13, 21, 25 adhesive layers

[0120] 20 Supporting components

[0121] 22 Semiconductor chips

[0122] 23 Sealing materials

[0123] 28. Wiring

[0124] 29 Solder bumps

Claims

1. A supporting glass substrate, which is used to support a processed substrate, characterized in that, The surface of the supporting glass substrate has an information recognition part with dots as structural units, the dots being formed by annular grooves, and the maximum length of the cracks extending from the annular grooves in the surface direction is more than 1 μm and less than 196 μm.

2. The supporting glass substrate according to claim 1, characterized in that, The average linear thermal expansion coefficient in the temperature range of 30℃ to 380℃ is 30×10. -7 / ℃ or above and 165×10 -7 / ℃ below.

3. The supporting glass substrate according to claim 1 or 2, characterized in that, It has a circular plate shape with a diameter of 100mm to 500mm, a plate thickness of less than 2.0mm, and an overall plate thickness deviation of less than 5μm.

4. The supporting glass substrate according to claim 1 or 2, characterized in that, It has a quadrilateral shape with each side being more than 300mm, a plate thickness of less than 2.0mm, and an overall plate thickness deviation of less than 10μm.

5. A laminated substrate comprising at least a processing substrate and a supporting glass substrate for supporting the processing substrate, characterized in that, The supporting glass substrate is the supporting glass substrate as described in claim 1 or 2.

6. The laminated substrate according to claim 5, characterized in that, The substrate being processed must have at least a semiconductor chip molded with a sealing material.

7. A method for manufacturing a semiconductor package, characterized in that, It has the following processes: The process of preparing a laminated substrate comprising at least a processing substrate and a supporting glass substrate for supporting the processing substrate; and The process of processing the substrate. Furthermore, the supporting glass substrate is the supporting glass substrate as described in any one of claims 1 to 4.

8. The method for manufacturing a semiconductor package according to claim 7, characterized in that, The processing includes the step of wiring one surface of the substrate.

9. The method for manufacturing a semiconductor package according to claim 7, characterized in that, The processing includes the step of forming solder bumps on one surface of a substrate.

10. A glass substrate, characterized in that, The surface has an information recognition part with points as structural units, the points being formed by annular grooves, and the maximum length of the cracks extending from the annular grooves in the surface direction is more than 1 μm and less than 196 μm.

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