Perforated glass substrate for semiconductor package, glass substrate for semiconductor package, and method for producing perforated glass substrate for semiconductor package

Abstract

The present invention addresses the problem of providing a perforated glass substrate for a semiconductor package. The perforated glass substrate is suitable for formation of a through-hole having a nearly straight shape, has excellent productivity, and is less likely to deform when mounting a semiconductor element thereon. A perforated glass substrate for a semiconductor package according to the present invention: has a first main surface, a second main surface that is the surface opposite to the first main surface, and through-holes that penetrate the substrate between the first main surface and the second main surface; and contains, in mol% as a glass composition, 55-85% of SiO2, 1-15% of Al2O3, 0-30% of B2O3, 0-0.1% of Li2O, 0-0.1% of Na2O, 0-0.1% of K2O, 0-20% of MgO, 0-15% of CaO, 0-10% of SrO, and 0-10% of BaO.

Description

Perforated glass substrate for semiconductor packaging, glass substrate for semiconductor packaging, and method for manufacturing a perforated glass substrate for semiconductor packaging

[0001] This invention relates to a perforated glass substrate for semiconductor packaging, a glass substrate for semiconductor packaging, and a method for manufacturing a perforated glass substrate for semiconductor packaging.

[0002] Development is underway for semiconductor package substrates that mount multiple semiconductor elements on a single electronic substrate (core substrate). Glass has excellent dimensional stability and low dielectric properties. Therefore, using glass as the material for the core substrate or the interposer that connects the semiconductor elements to the core substrate can improve the performance of the semiconductor package substrate. When using a glass substrate as a glass core substrate or glass interposer, it is necessary to form through electrodes to make the front and back surfaces of the glass substrate electrically conductive. These through electrodes are formed by creating fine through holes and filling the inside of the through holes with a conductive material.

[0003] A known method for accurately forming through-holes in a glass substrate involves irradiating the glass substrate with a pulsed laser to create a modified area where the through-hole is to be formed, and then etching the modified area off the glass substrate to form the through-hole. Through-holes formed by this method have a tapered shape, but for high-density semiconductor mounting, it is preferable that the diameter of the through-hole on the glass surface is small, that is, that the taper angle of the through-hole is small and it is close to a straight shape.

[0004] To form through holes that are close to a straight shape, the SiO of the glass substrate ２ Increasing the content, Al ２ O ３ , B ２ O ３ Such SiO ２ It is known to be effective to regulate the content of glass skeleton-forming components other than (see, for example, Patent Documents 1 and 2).

[0005] Japanese Patent Publication No. 2023-018034 Japanese Special Publication No. 2022-531500

[0006] Incidentally, in order to facilitate the formation of through-holes in a glass substrate that are close to a straight shape, increasing the content of SiO in the glass ２ deteriorates the melting property and formability, and increases the manufacturing cost. However, the patent documents 1 and 2 do not describe the composition range of glass that can form through-holes close to a straight shape and has excellent melting properties.

[0007] Further, when mounting a semiconductor element on a glass substrate, if the difference in the coefficient of thermal expansion between the mounted semiconductor element and the glass substrate is large, when the temperature is raised and lowered during the mounting of the semiconductor element, the substrate may deform, leading to breakage of the semiconductor element or the glass substrate. Therefore, when mounting a semiconductor element on a core substrate or an interposer using a glass substrate, the coefficient of thermal expansion is particularly important, but the patent documents 1 and 2 do not describe a preferable coefficient of thermal expansion.

[0008] In view of the above problems, an object of the present invention is to provide a perforated glass substrate for a semiconductor package, a glass substrate for a semiconductor package, and a method for manufacturing a perforated glass substrate for a semiconductor package, which are suitable for forming through-holes close to a straight shape, have excellent productivity, and are less likely to cause deformation of the substrate when mounting a semiconductor element.

[0009] As a result of repeating various experiments, the inventor of the present invention has found that the above technical problems can be solved by strictly regulating the glass composition of the glass substrate, and proposes the present invention.

[0010] (1) The perforated glass substrate for a semiconductor package of the present invention devised to solve the above problems includes a first main surface, a second main surface that is the opposite surface of the first main surface, and a through-hole that penetrates between the first main surface and the second main surface. The perforated glass substrate for a semiconductor package, wherein the glass composition is, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B ２ O ３ 0 to 30%, Li ２ O 0 to 0.1%, Na ２ O 0 to 0.1%, K ２It is characterized by containing 0-0.1% O, 0-20% MgO, 0-15% CaO, 0-10% SrO, and 0-10% BaO.

[0011] (2) In the configuration of (1) above, the glass composition is SiO in mol% ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-30%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is characterized by containing 0-0.1% O, 0-10% MgO, 0-10% CaO, 0-10% SrO, and 0-10% BaO.

[0012] (3) In the configuration of (1) above, the glass composition is SiO in mol% ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-20%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is preferable that the mixture contains 0-0.1% O, 0-10% MgO, 0-10% CaO, 0-10% SrO, and 0-10% BaO.

[0013] (4) In the configuration of (1) above, the glass composition is SiO in mol% ２ 55-71.5%, Al ２ O ３ 5-14%, B ２ O ３ 0-8%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is preferable that the mixture contains 0-0.1% O, 0-7% MgO, 0-10% CaO, 0-2.4% SrO, and 0-4.5% BaO.

[0014] (5) In the configuration of (1) above, the glass composition is SiO in mol% ２ 55-71.5%, Al ２ O３ 5-14%, B ２ O ３ 3-8%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is preferable that the mixture contains 0-0.1% O, 0-5% MgO, 3.5-10% CaO, 0-4% SrO, and 0-1% BaO.

[0015] (5) In the configuration of (4) above, the glass composition is TiO in mol%. ２ It is preferable to further contain 0 to 0.01%.

[0016] (6) In the configuration of (1) above, the glass composition is SiO in mol% ２ 65-71.5%, Al ２ O ３ 5-14%, B ２ O ３ 0-10%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is preferable that the mixture contains 0-0.1% O, 0-5% MgO, 5-10% CaO, 0-3% SrO, and 0-3% BaO.

[0017] (7) In the configuration of (1) above, the glass composition is SiO in mol% ２ 65-75%, Al ２ O ３ 5-14%, B ２ O ３ 5-15%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is preferable that the mixture contains 0-0.1% O, 4-8% MgO, 0-3% CaO, 1-5% SrO, and 0-2% BaO.

[0018] (8) In the configuration of (1) above, the glass composition is SiO in mol% ２ 55-65%, Al ２ O ３ 5-14%, B ２ O ３ 5-15%, Li ２O 0 to 0.1%, Na ２ O 0 to 0.1%, K ２ It is preferable to contain O 0 to 0.1%, MgO 5 to 10%, CaO 5 to 10%, SrO 0 to 3%, and BaO 0 to 5%.

[0019] (9) In the configuration of (1) above, as the glass composition, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B<​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​(13) In any of the configurations (1) to (12) above, it is preferable that the Young's modulus is 70 GPa or more.

[0024] (14) In any of the configurations (1) to (13) above, it is preferable that the thickness of the glass substrate is 0.03 mm or more and 2 mm or less, the TTV of the glass substrate is 20 μm or less, and the warpage amount of the glass substrate is 60 μm or less.

[0025] (15) In any of the configurations (1) to (14) above, it is preferable that the HF etching rate is 1.5 μm / min or less.

[0026] (16) In any of the configurations (1) to (15) above, it is preferable that the side surface of the through hole is inclined with respect to the plate thickness direction, and the average taper angle of the side surface is more than 0° and 13° or less.

[0027] (17) In any of the configurations (1) to (16) above, the through hole has a constricted portion having a diameter smaller than the diameters of the through holes on the first main surface and the second main surface at the central portion in the plate thickness direction of the glass substrate, and the diameter of the constricted portion is preferably 50% or more and 99% or less of the diameter of the through hole on the first main surface and the diameter of the through hole on the second main surface.

[0028] (18) In any of the configurations (1) to (17) above, it is preferable that the diameter of the through hole on the first main surface is 5 μm or more and 200 μm or less, and the diameter of the through hole on the second main surface is 5 μm or more and 200 μm or less.

[0029] (19) In any of the configurations (1) to (18) above, it is preferable that at least the inner surface of the through hole is an etched surface.

[0030] (20) The glass substrate for a semiconductor package of the present invention devised to solve the above problems is a glass substrate used for manufacturing a perforated glass substrate for a semiconductor package having through holes. As the glass composition, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B ２ O ３ 0 to 30%, Li ２O 0-0.1%, Na ２ O 0-0.1%, K ２ It is characterized by containing 0-0.1% O, 0-20% MgO, 0-15% CaO, 0-10% SrO, and 0-10% BaO.

[0031] (21) The present invention, which was devised to solve the above problems, is characterized by comprising: a preparation step of preparing a glass substrate having the configuration of (20) above; a laser irradiation step of irradiating the portion of the glass substrate where through holes are to be formed with laser light to form a modified portion; and an etching step of etching the glass substrate having the modified portion to form through holes.

[0032] (22) A perforated glass substrate for semiconductor packaging comprising a first main surface, a second main surface which is the opposite surface of the first main surface, and non-through holes formed in the first main surface and the second main surface, wherein the glass composition is SiO in mol% ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-30%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ It is characterized by containing 0-0.1% O, 0-20% MgO, 0-15% CaO, 0-10% SrO, and 0-10% BaO.

[0033] According to the present invention, it is possible to provide a perforated glass substrate for semiconductor packaging, a glass substrate for semiconductor packaging, and a method for manufacturing a perforated glass substrate for semiconductor packaging, which are suitable for forming through holes that are close to a straight shape, have excellent productivity, and are less prone to deformation of the substrate when semiconductor elements are mounted.

[0034] Figure 1 is a schematic diagram showing the annealing temperature profile when measuring the HF etching rate of a glass substrate according to one embodiment of the present invention. Figure 2 is a top view showing a perforated glass substrate according to one embodiment of the present invention. Figure 3 is a cross-sectional view taken along line A-A of the perforated glass substrate of Figure 2. Figure 4 is a schematic cross-sectional view showing a first example of through holes formed in a perforated glass substrate according to one embodiment of the present invention. Figure 5 is a schematic cross-sectional view showing a second example of through holes formed in a perforated glass substrate according to one embodiment of the present invention. Figure 6 is a top view showing a perforated glass substrate having non-through holes according to one embodiment of the present invention. Figure 7 is a cross-sectional view taken along line B-B of the perforated glass substrate of Figure 6. Figure 8 is a schematic cross-sectional view showing a non-through hole formed in a perforated glass substrate according to one embodiment of the present invention. Figure 9 is a flow chart showing a method for manufacturing a perforated glass substrate according to one embodiment of the present invention. Figure 10 is a perspective view showing a laser irradiation process according to one embodiment of the present invention. Figure 11 is a schematic diagram for comparing a glass substrate before through hole formation and a perforated glass substrate after through hole formation according to one embodiment of the present invention.

[0035] Embodiments of the present invention will be described below with reference to the drawings.

[0036] [First Embodiment] First, the glass composition and properties of the glass substrate for semiconductor packaging (hereinafter referred to as "glass substrate") according to the first embodiment of the present invention will be described. The glass substrate according to this embodiment is used in the manufacture of a perforated glass substrate having through holes, and is a glass substrate (non-perforated glass substrate) in the state before the through holes are formed.

[0037] The glass substrate according to the first embodiment has a glass composition of SiO in mol%. ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-30%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２It is characterized by containing 0-0.1% O, 0-20% MgO, 0-15% CaO, 0-10% SrO, and 0-10% BaO. The reasons for limiting the content of each component as described above are shown below. In the description of the content of each component, percentages represent moles unless otherwise specified.

[0038] SiO ２ SiO is a component that forms the framework of glass. ２ If the content is too low, chemical resistance decreases. In particular, the HF etching rate increases, which increases the rate of hole diameter expansion when forming through holes, and the taper angle of the through hole becomes larger. In other words, it becomes difficult to form through holes that are close to a straight shape. Therefore, SiO ２ The lower limit of the amount is 55% or more, preferably 60% or more, more preferably 63% or more, and particularly preferably 65% ​​or more. Furthermore, from the viewpoint of particularly emphasizing the reduction of the HF etching rate, 68% or more is even more preferable. On the other hand, SiO ２ If the content is too high, the high-temperature viscosity increases, requiring more heat for melting, which raises the melting cost, and also increases the SiO content. ２ Undissolved raw materials may remain, potentially leading to a decrease in yield. Furthermore, cristobalite is more likely to precipitate during molding. Therefore, SiO ２ The upper limit of the amount is 85% or less, preferably 75% or less, more preferably 74.8% or less, more preferably 73% or less, more preferably 72% or less, more preferably 71.5% or less, more preferably 71% or less, and particularly preferably 70% or less. Furthermore, from the viewpoint of particularly emphasizing meltability, 65% or less is even more preferable.

[0039] Al ２ O ３ Al is a component that forms the framework of glass. ２ O ３ If the content is too low, chemical resistance will decrease. In particular, the HF etching rate will increase, which will increase the rate at which the hole diameter expands when forming through holes, and the taper angle of the through hole will become larger. In other words, it will become difficult to form through holes that are close to a straight shape. Therefore, Al ２ O ３The lower limit of is 1% or more, preferably 5% or more, more preferably 7% or more, more preferably 8.5% or more, and particularly preferably 9.5% or more. On the other hand, Al ２ O ３ If the content of Al is too high, the high-temperature viscosity increases, and the mass of residue generated when etching through holes in the glass substrate increases. High high-temperature viscosity tends to reduce meltability and moldability. Also, an increase in the mass of residue makes it easier for residue clogging to occur in the etching equipment, increasing the frequency of residue processing and raising the manufacturing cost of the glass substrate. Furthermore, an increase in the mass of residue causes residue to adhere to the inside of through holes when etching through holes in the glass substrate, hindering the supply of etching solution to the inside of the through holes. This can lead to a larger taper angle in the through holes (i.e., difficulty in forming straight through holes) or a larger variation in the diameter of the through holes. Therefore, Al ２ O ３ The upper limit of the amount is 15% or less, preferably 14% or less, more preferably 13.5% or less, more preferably 13% or less, more preferably 12.9% or less, and particularly preferably 12.7% or less.

[0040] Also, Al ２ O ３ If the content of is too high, the relative permittivity and dielectric loss tangent of the glass tend to increase. When using glass substrates as core substrates or interposers for high-frequency device applications, it is preferable to have low relative permittivity and dielectric loss tangent in order to reduce transmission loss of high-frequency signals. Therefore, from the viewpoint of particularly reducing relative permittivity and dielectric loss tangent, Al ２ O ３ The upper limit of the amount is preferably 12% or less, more preferably 10% or less, more preferably 9% or less, more preferably 8% or less, more preferably 7% or less, more preferably 6% or less, and particularly preferably 5% or less.

[0041] B ２ O ３ This component forms the framework of the glass and also reduces its high-temperature viscosity. ２ O ３If the content is too low, the high-temperature viscosity will increase, and meltability and moldability will easily decrease. Therefore, B ２ O ３ The lower limit of is 0% or more, preferably 3% or more, more preferably 5% or more, and particularly preferably 7% or more. On the other hand, B ２ O ３ If the content is too high, the chemical resistance decreases and the glass becomes more prone to phase separation. In particular, the HF etching rate increases, so the taper angle when forming through holes becomes larger. Also, when the glass splits into phases, the glass substrate becomes cloudy and the transmittance of the glass substrate decreases. As a result, when laser light is irradiated onto the glass substrate to form the modified area, the laser light is scattered, making it difficult to form the modified area. Therefore, B ２ O ３ The upper limit of the amount is 30% or less, preferably 28% or less, more preferably 27% or less, more preferably 25% or less, more preferably 23% or less, more preferably 20% or less, more preferably 18% or less, more preferably 16% or less, more preferably 15% or less, more preferably 14% or less, more preferably 12% or less, more preferably 10% or less, more preferably 8% or less, and particularly preferably 7.2% or less.

[0042] Also, B ２ O ３ This is a component that reduces the relative permittivity and dielectric loss tangent. When using glass substrates as core substrates or interposers for high-frequency device applications, it is preferable to have low relative permittivity and dielectric loss tangent in order to reduce transmission loss of high-frequency signals. Therefore, from the viewpoint of reducing relative permittivity and dielectric loss tangent in particular, B ２ O ３ The lower limit of the amount is preferably 9% or more, more preferably 10% or more, more preferably 11% or more, more preferably 12% or more, more preferably 13% or more, more preferably 14% or more, more preferably 15% or more, more preferably 16% or more, more preferably 17% or more, more preferably 18% or more, more preferably 19% or more, more preferably 20% or more, more preferably 21% or more, more preferably 22% or more, more preferably 23% or more, and more preferably 24% or more, and particularly preferably 25% or more.

[0043] Li ２ O is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. Therefore, Li ２ The lower limit of O is 0% or more, preferably 0.0005% or more. On the other hand, Li ２ If the O content is too high, batch costs will increase, and manufacturing costs will rise. Also, the thermal expansion coefficient of the glass will increase, making it difficult to design a product that matches the thermal expansion coefficient of Si. Therefore, Li ２ The upper limit of O is 0.1% or less, preferably 0.05% or less, more preferably 0.03% or less, more preferably 0.01% or less, and particularly preferably 0.001% or less.

[0044] Na ２ O is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. Therefore, Na ２ The lower limit of O is 0% or more, preferably 0.001% or more, more preferably 0.005% or more, more preferably 0.01% or more, and particularly preferably 0.05% or more. On the other hand, Na ２ If the O content is too high, the coefficient of thermal expansion will increase, which can lead to excessive deformation of the glass substrate during semiconductor device mounting and potentially cause damage to the glass substrate or semiconductor device. Also, Na ２ If the O content is too high, the leaching of alkaline components during the manufacturing of semiconductor packages may degrade the functionality of the packages. Therefore, Na ２ The upper limit of O is 0.1% or less, preferably 0.09% or less, more preferably 0.08% or less, more preferably 0.07% or less, and particularly preferably 0.065% or less.

[0045] K ２ O is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. Therefore, K ２ The lower limit of O is 0% or more, preferably 0.0005% or more, more preferably 0.0006% or more, more preferably 0.0007% or more, and particularly preferably 0.0009% or more. On the other hand, K ２If the O content is too high, the coefficient of thermal expansion will increase, which may lead to excessive deformation of the glass substrate during semiconductor device mounting, potentially causing damage to the glass substrate or semiconductor device. Also, K ２ If the O content is too high, dielectric loss increases, and the device characteristics of the glass substrate tend to deteriorate. Therefore, K ２ The upper limit of O is 0.1% or less, preferably 0.09% or less, more preferably 0.05% or less, more preferably 0.03% or less, and particularly preferably 0.01% or less.

[0046] MgO is an optional component that enhances HF resistance and also reduces the high-temperature viscosity of the glass, thereby improving meltability, and its content may be 0%. If the MgO content is too low, the HF etching rate increases, and the taper angle of the through-hole tends to become larger. Also, if the MgO content is too low, the high-temperature viscosity increases, and meltability and moldability tend to decrease. Therefore, the lower limit of MgO is 0% or more, preferably 0.1% or more, more preferably 0.5% or more, more preferably 0.9% or more, more preferably 1% or more, more preferably 1.1% or more, more preferably 3% or more, more preferably 4% or more, and particularly preferably 5% or more. Furthermore, from the viewpoint of particularly improving the meltability of the glass, the lower limit of MgO is preferably 6% or more, more preferably 8% or more, more preferably 10% or more, more preferably 12% or more, more preferably 14% or more, more preferably 15% or more, and particularly preferably 16% or more. On the other hand, if the MgO content is too high, the glass is more likely to undergo phase separation, and the transmittance of the glass substrate decreases. As a result, when laser light is irradiated onto the glass substrate to form through holes, the laser light is scattered, making it difficult to form modified areas. Therefore, the upper limit of MgO is 20% or less, preferably 18% or less, more preferably 16% or less, more preferably 14% or less, more preferably 12% or less, more preferably 10% or less, more preferably 9% or less, more preferably 8.5% or less, more preferably 8% or less, more preferably 7% or less, more preferably 6% or less, and particularly preferably 5% or less.

[0047] CaO is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. Therefore, the lower limit of CaO is 0% or more, preferably 0.1% or more, more preferably 0.5% or more, more preferably 0.9% or more, more preferably 1% or more, more preferably 3% or more, more preferably 3.5% or more, and particularly preferably 5% or more. Furthermore, from the viewpoint of particularly increasing the meltability of the glass, the lower limit of CaO is preferably 6% or more, more preferably 7% or more, more preferably 8% or more, and particularly preferably 9% or more. On the other hand, if the CaO content is too high, the mass of residue generated when etching the glass substrate to form through holes increases. This makes it easier for residue clogging to occur in the etching apparatus, increases the frequency of residue processing, and raises the manufacturing cost of the glass substrate. The mass of the residue generated at this time is proportional to the formula weight of the salt composed of alkaline earth metal, Al, and F, so the larger the atomic weight of the alkaline earth metal, the more likely this problem is to become apparent. In particular, when forming through holes by etching, in addition to the reduction in the thickness of the glass substrate, residue equivalent to the volume of the through hole is generated. When many through holes are made in the glass substrate, the amount of residue generated is proportional to the number of through holes, which tends to increase manufacturing costs. Furthermore, as the mass of the residue increases, when etching the glass substrate to form through holes, the residue adheres to the inside of the through holes, hindering the supply of etching solution to the inside of the through holes. As a result, the taper angle of the through holes becomes larger (i.e., it becomes difficult to form straight-shaped through holes), and the variation in the diameter of the through holes increases. Therefore, the upper limit of CaO is 15% or less, preferably 14% or less, more preferably 13% or less, more preferably 12% or less, more preferably 11% or less, more preferably 10% or less, more preferably 9.5% or less, more preferably 9.3% or less, more preferably 9% or less, more preferably 8.9% or less, and particularly preferably 6% or less. In particular, from the viewpoint of reducing the taper angle of the through holes and forming through holes that are close to a straight shape, it is preferably 3% or less.

[0048] SrO is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. Therefore, the lower limit of SrO is 0% or more, preferably 0.1% or more, more preferably 0.2% or more, and particularly preferably 1% or more. On the other hand, if the SrO content is too high, the coefficient of thermal expansion will increase, which may lead to greater deformation of the glass substrate during semiconductor device mounting and damage to the glass substrate or semiconductor device. Also, if the SrO content is too high, the mass of residue generated when etching the glass substrate to form through holes will increase. This makes it easier for residue to clog the etching equipment, increasing the frequency of residue processing and raising the manufacturing cost of the glass substrate. Furthermore, when the mass of residue increases, when etching the glass substrate to form through holes, the residue adheres to the inside of the through holes, hindering the supply of etching solution to the inside of the through holes. As a result, the taper angle of the through holes may increase (i.e., it may become difficult to form straight-shaped through holes), or the variation in the diameter of the through holes may increase. Therefore, the upper limit of SrO is 10% or less, preferably 8% or less, more preferably 5% or less, more preferably 4% or less, more preferably 3% or less, and particularly preferably 2.4% or less.

[0049] BaO is an optional component that reduces the high-temperature viscosity of the glass and increases its meltability, and its content may be 0%. It is also a component that enhances resistance to devitrification. If the BaO content is too low, it becomes difficult to enjoy the above effects. When the glass devitrifies, the glass substrate becomes cloudy and the transmittance of the glass substrate decreases. As a result, when laser light is irradiated onto the glass substrate to form the modified area, the laser light is scattered, and it becomes difficult to form the modified area, especially in the central part in the thickness direction of the plate. Consequently, when the modified area is removed by etching, it is more difficult to remove the central part in the thickness direction of the glass substrate compared to the vicinity of the main surface of the glass substrate, the taper angle of the through-hole or non-through-hole becomes larger, and it becomes difficult to form through-hole or non-through-hole that are close to a straight shape. Therefore, the lower limit of the amount of BaO is 0% or more, more preferably 0.1% or more, more preferably 0.2% or more, more preferably 1% or more, and particularly preferably 2% or more. On the other hand, if the BaO content is too high, the coefficient of thermal expansion increases, which can lead to greater deformation of the glass substrate during semiconductor device mounting and potentially cause damage to the glass substrate or semiconductor device. Also, if the BaO content is too high, the mass of residue generated when etching the glass substrate to form through holes increases. This makes residue clogging more likely in the etching equipment, increasing the frequency of residue processing and raising the manufacturing cost of the glass substrate. Furthermore, when the mass of residue increases, residue adheres to the inside of the through holes when etching the glass substrate to form through holes, hindering the supply of etching solution to the inside of the through holes. This can result in a larger taper angle of the through holes (i.e., difficulty in forming straight through holes) or a larger variation in the diameter of the through holes. Therefore, the upper limit of the BaO content is 10% or less, preferably 8% or less, more preferably 6% or less, more preferably 5% or less, more preferably 4.5% or less, more preferably 4% or less, and more preferably 3% or less. Furthermore, from the viewpoint of reducing the amount of residue generated during etching, it is preferably 2% or less, and particularly preferably 1% or less.

[0050] If the total content of MgO, CaO, SrO, and BaO is too low, the high-temperature viscosity will increase, and meltability and moldability will tend to decrease. Therefore, the lower limit range for the total content of MgO, CaO, SrO, and BaO is preferably 0% or more, more preferably 3% or more, more preferably 5% or more, and particularly preferably 10% or more. On the other hand, if the total content of MgO, CaO, SrO, and BaO is too high, the coefficient of thermal expansion will increase, which may lead to greater deformation of the glass substrate during semiconductor device mounting, potentially causing damage to the glass substrate or semiconductor device. Also, if the total content of MgO, CaO, SrO, and BaO is too high, the mass of residue generated when etching the glass substrate to form through holes will increase. This makes residue clogging more likely in the etching equipment, increases the frequency of residue processing, and raises the manufacturing cost of the glass substrate. Furthermore, as the mass of the residue increases, when etching the glass substrate to form through holes, the residue adheres to the inside of the through holes, hindering the supply of etching solution to the inside of the through holes. As a result, the taper angle of the through holes becomes larger (i.e., it becomes difficult to form straight through holes), and the variation in the diameter of the through holes increases. Therefore, the upper limit range of the total content of MgO, CaO, SrO, and BaO is preferably 30% or less, more preferably 28% or less, more preferably 26% or less, more preferably 24% or less, more preferably 22% or less, more preferably 20% or less, more preferably 18% or less, more preferably 16% or less, and particularly preferably 14% or less.

[0051] Y ２ O ３ , Nb ２ O ５ La ２ O ３ These are components that enhance mechanical properties such as Young's modulus, but if the total amount and individual content of these components are too high, raw material costs tend to increase. Therefore, Y ２ O ３ , Nb ２ O ５ La ２ O ３The upper limits for the total amount and individual content are preferably 10% or less, more preferably 8% or less, more preferably 6% or less, more preferably 4% or less, more preferably 2% or less, more preferably 1% or less, more preferably 0.5% or less, and particularly preferably 0.3% or less. ２ O ３ , Nb ２ O ５ La ２ O ３ The lower limits of the total amount and individual content are preferably 0% or more, more preferably 0.01% or more, more preferably 0.05% or more, and particularly preferably 0.1% or more.

[0052] ZrO ２ ZrO is a component that inevitably gets mixed in from refractories used in glass manufacturing furnaces. ２ If the content is too high, devitrified crystals are more likely to precipitate. Therefore, ZrO ２ The upper limit of is preferably 5% or less, more preferably 4% or less, more preferably 3% or less, more preferably 2% or less, more preferably 1% or less, and particularly preferably 0.5% or less. On the other hand, ZrO ２ To reduce the content of ZrO, the melting temperature must be lowered, which makes it difficult to melt the glass. Therefore, ZrO ２ The lower limit of the amount is preferably 0% or more, more preferably 0.01% or more, more preferably 0.05% or more, and particularly preferably 0.1% or more.

[0053] SnO ２ SnO is a component that has a good clarifying effect in the high-temperature range, and is also an optional component that reduces high-temperature viscosity and improves meltability. Therefore, in order to produce glass substrates with good yield, SnO ２ It is preferable to include SnO ２ The content of may be 0%. Also, when forming wiring on the main surface of a glass substrate, if bubbles are exposed on the main surface, there is a risk of the wiring breaking. In particular, in recent years, wiring has become smaller and smaller, and even minute bubbles that are difficult to detect by image inspection machines, etc., may cause the wiring to break. For this reason, the glass substrate according to this embodiment is SnO ２It is preferable to increase the content of SnO to enhance the clarification effect and reduce the amount of foam. ２ The lower limit of the amount is preferably 0% or more, more preferably 0.01% or more, more preferably 0.02% or more, and particularly preferably 0.05% or more. On the other hand, SnO ２ If the content is too high, SnO ２ Devitrified crystals are more likely to precipitate, which may lead to a decrease in yield. Therefore, SnO ２ The upper limit of the amount is preferably 1% or less, more preferably 0.9% or less, more preferably 0.7% or less, and particularly preferably 0.4% or less.

[0054] As described above, SnO ２ While is suitable as a clarifying agent, as long as the glass properties are not impaired, SnO ２ Instead, or SnO ２ Along with F, SO ３ Metal powders such as C, Al, or Si can be added in amounts up to 0.5% each (preferably up to 0.4%, particularly preferably up to 0.3%). Additionally, CeO can be used as a clarifying agent. ２ It can also be added, but CeO ２ If the content is too high, the glass will become discolored, and when a laser beam is shone onto the glass substrate to form the modified area, the heat generated at the laser irradiation area will increase, making it easier for defects such as cracks to occur. For this reason, CeO ２ The upper limit is preferably 0.5% or less, more preferably 0.4% or less, and particularly preferably 0.3% or less.

[0055] Cl is an optional component that promotes the initial melting of the glass batch. Adding Cl can also enhance the action of the clarifying agent. As a result, melting costs can be reduced while extending the lifespan of the glass manufacturing furnace; however, the Cl content may be as low as 0%. Therefore, the lower limit of Cl is preferably 0% or more, more preferably 0.0001% or more, more preferably 0.0005% or more, more preferably 0.0008% or more, and particularly preferably 0.001% or more. On the other hand, if the Cl content is too high, the volatile Cl components released during melting may damage the melting furnace, potentially increasing manufacturing costs. Therefore, the upper limit of Cl is preferably 0.01% or less, more preferably 0.008% or less, more preferably 0.007% or less, and particularly preferably 0.005% or less. For example, NaCl can be used as the raw material for introducing Cl. Furthermore, since Cl is a volatile component during melting, the Cl content in the batch may be appropriately adjusted during manufacturing so that the amount of Cl in the molded glass substrate meets the aforementioned range.

[0056] As a clarifying agent, ２ O ３ Sb ２ O ３ This is also effective. However, As ２ O ３ Sb ２ O ３ These are components that increase the environmental burden. Therefore, it is preferable that the glass substrate according to this embodiment substantially does not contain these components, and the range is preferably 0 to 0.1%.

[0057] In this embodiment, the glass substrate uses SnO as a clarifying agent to promote clarification and reduce melting costs. ２ Preferably, the mixture contains at least one of the following: , and chlorine.

[0058] In addition to the above components, the following components may be added as optional components. However, from the viewpoint of effectively enjoying the effects of the present invention, the total amount of other components is preferably 1% or less, and particularly preferably 0.5% or less.

[0059] TiO ２This is an optional component that lowers high-temperature viscosity and increases meltability, and its content may be 0%. Therefore, TiO ２ The lower limit of TiO is preferably 0% or more, more preferably 0.0001% or more, more preferably 0.0005% or more, and particularly preferably 0.0006% or more. ２ If a large amount of TiO is included, the glass substrate will become discolored, and when the glass substrate is irradiated with laser light to form the modified area, the heat generated at the laser irradiation area will increase, making it easier for defects such as cracks to occur. Therefore, TiO ２ The upper limit is preferably 0.01% or less, more preferably 0.009% or less, more preferably 0.008% or less, and particularly preferably 0.006% or less.

[0060] ZnO is an optional component used to lower high-temperature viscosity and improve meltability, and its content may be 0%. Therefore, the lower limit of ZnO is preferably 0% or more, more preferably 0.1% or more, more preferably 0.3% or more, and particularly preferably 0.6% or more. On the other hand, if a large amount of ZnO is included, the glass substrate will become discolored, and when the glass substrate is irradiated with laser light to form the modified portion, the heat generated at the laser irradiation area will increase, making it easier for defects such as cracks to occur. Therefore, the upper limit of ZnO is preferably 10% or less, more preferably 9% or less, more preferably 8% or less, more preferably 7% or less, more preferably 6% or less, more preferably 5% or less, more preferably 4% or less, more preferably 3% or less, more preferably 2% or less, more preferably 1% or less, more preferably 0.9% or less, more preferably 0.85% or less, and particularly preferably 0.8% or less.

[0061] P ２ O ５ This is an optional component that enhances HF resistance and facilitates the formation of through holes in the glass substrate that are close to a straight shape, and its content may be 0%. Therefore, P ２ O ５ The lower limit of P is preferably 0% or more, more preferably 0.01% or more, and particularly preferably 0.05% or more. On the other hand, P ２ O ５When a large amount of is included, the glass becomes more prone to phase separation. When the glass separates, the glass substrate becomes cloudy and the transmittance of the glass substrate decreases. As a result, when laser light is irradiated onto the glass to form the modified area, the laser light is scattered, making it difficult to form the modified area. Therefore, P ２ O ５ The upper limit of the amount is preferably 1% or less, more preferably 0.5% or less, more preferably 0.3% or less, and particularly preferably 0.2% or less.

[0062] CuO is an optional component for coloring the glass, and its content may be 0%. If the CuO content is too high, the glass substrate will become colored, and when the glass substrate is irradiated with laser light to form through holes, the heat generated at the laser irradiation site will increase, making it easier for defects such as cracks to occur. Therefore, it is desirable to have a low CuO content, and its upper limit is preferably 1% or less, more preferably less than 0.5%, and particularly preferably 0.2% or less. The lower limit of CuO may be, for example, 0.01% or more.

[0063] Fe ２ O ３ Fe is a component that is inevitably mixed in from the glass raw materials, and is also a component that colors the glass. ２ O ３ If the content is too low, raw material costs tend to rise. On the other hand, Fe ２ O ３ If the content is too high, the glass substrate will become discolored, and when laser light is shone onto the glass substrate to form through holes, the heat generated at the laser irradiation site will increase, making it easier for defects such as cracks to occur. Therefore, Fe ２ O ３ The content is preferably 0 to 200 ppm, more preferably 1 to 150 ppm, and particularly preferably 30 to 100 ppm.

[0064] The glass substrate according to the first embodiment preferably has the following characteristics.

[0065] The HF etching rate is preferably 1.5 μm / min or less, more preferably 1.4 μm / min or less, more preferably 1.3 μm / min or less, more preferably 1.2 μm / min or less, more preferably 1.1 μm / min or less, more preferably 1 μm / min or less, more preferably 0.9 μm / min or less, more preferably 0.8 μm / min or less, more preferably 0.7 μm / min or less, and particularly preferably 0.6 μm / min or less. When the HF etching rate is within this range, the HF etching rate is low in the unmodified parts of the glass substrate, making it difficult for the hole diameter on the main surface of the glass substrate to enlarge when forming through holes, and allowing for a smaller taper angle. As a result, it becomes easier to make the glass substrate thicker, making it less likely for the glass substrate to deform during film deposition or semiconductor device mounting, and preventing damage to the glass substrate and semiconductor devices. The HF etching rate may be, for example, 0.1 μm / min or more. Note that the HF etching rate may change not only depending on the glass composition but also on the virtual temperature and phase state of the glass.

[0066] (Method for measuring HF etching rate) Here, the HF etching rate refers to the value measured by the following method. First, both sides of a glass substrate sample with a thickness of 1 mm and dimensions of 20 mm x 35 mm are optically polished. Then, the glass substrate sample is annealed according to the temperature profile shown in Figure 1, and a part of the main surface is masked. In this annealing, the glass substrate is heated from 25°C to (Ta + 30°C) at a rate of 5°C / min, held at (Ta + 30°C) for 30 minutes, then cooled from (Ta + 30°C) to (Ta - 170°C) at a rate of -3°C / min, and then cooled from (Ta - 170°C) to 25°C at a rate of -10°C / min. Here, Ta means the slow cooling point. Next, the glass substrate sample is immersed in the etching solution for 10 minutes to perform etching. 300 mL of a 2.5 mol / L HF aqueous solution is used as the etching solution. When etching, a water bath stirrer is set to 30°C and stirred at approximately 600 rpm. After that, the mask is removed, the glass substrate sample is washed, and the step height between the masked area and the eroded area is measured using a SurfCorder (ET4000A: manufactured by Kosaka Laboratory Co., Ltd.). The HF etching rate is calculated by dividing the height of this step height by the immersion time.

[0067] The average thermal expansion coefficient CTE in the temperature range of 30 to 380°C is preferably 2.8 × 10⁻⁶. －６ / ℃ or higher, more preferably 3 × 10 －６ / ℃ or higher, more preferably 3.1 × 10 －６ / ℃ or higher, particularly preferably 3.2 × 10 －６ It is above / °C. Furthermore, the average coefficient of thermal expansion CTE in the temperature range of 30 to 380°C is preferably 4.5 × 10⁻⁶. －６ / ℃ or less, more preferably 4.3 × 10 －６ / ℃ or less, more preferably 4.1 × 10 －６ / ℃ or lower, particularly preferably 4 × 10 －６ The temperature is below / °C. This makes it easier to match the thermal expansion coefficient of Si when mounting semiconductor elements, reduces deformation of the glass substrate, and prevents damage to the glass substrate and semiconductor elements.

[0068] The Young's modulus is preferably 70 GPa or higher, more preferably 73 GPa or higher, more preferably 74 GPa or higher, and particularly preferably 75 GPa or higher. This makes it less likely for the glass substrate to deform when semiconductor elements are mounted, and prevents damage to the glass substrate and semiconductor elements.

[0069] The strain point is preferably 500°C or higher, more preferably 600°C or higher, more preferably 620°C or higher, more preferably 650°C or higher, and particularly preferably 700°C or higher. With such a strain point, the peel strength can be increased by raising the heat treatment temperature in the plating process on the glass substrate, and deformation of the substrate during heat treatment can be suppressed.

[0070] The annealing point is preferably 550°C or higher, more preferably 600°C or higher, more preferably 650°C or higher, more preferably 700°C or higher, more preferably 720°C or higher, more preferably 740°C or higher, more preferably 760°C or higher, more preferably 780°C or higher, and particularly preferably 800°C or higher. With such an annealing point, the peel strength can be increased by raising the heat treatment temperature in the plating process on the glass substrate, and deformation of the substrate during heat treatment can be suppressed.

[0071] The softening point is preferably 1100°C or lower, more preferably 1080°C or lower, more preferably 1050°C or lower, and particularly preferably 1000°C or lower. With such a softening point, the process temperature when performing heat treatment to improve the plate quality and phase separation state of the glass substrate can be lowered, thereby reducing manufacturing costs.

[0072] The liquidus temperature is preferably 1300°C or lower, more preferably less than 1250°C, more preferably 1200°C or lower, and particularly preferably 1190°C or lower. This makes it easier to prevent the formation of devitrified crystals during molding, which can reduce productivity. Furthermore, it makes molding easier using the overflow down-draw method, which improves the surface quality of the glass substrate and reduces the manufacturing cost of the glass substrate. The liquidus temperature is an indicator of devitrification resistance; the lower the liquidus temperature, the better the devitrification resistance.

[0073] The liquid-phase viscosity is preferably 10 ４．０ dPa·s or higher, more preferably 10 ４．２ dPa·s or higher, more preferably 10 ４．４ dPa·s or higher, particularly preferably 10 ４．６ The viscosity is dPa·s or higher. This reduces the likelihood of devitrification during molding and lowers the manufacturing cost of the glass substrate. Liquid-phase viscosity is an indicator of devitrification resistance and moldability; the higher the liquid-phase viscosity, the better the devitrification resistance and moldability.

[0074] High temperature viscosity 10 ２．５ The temperature at dPa·s is preferably 1680°C or lower, more preferably 1660°C or lower, more preferably 1640°C or lower, and particularly preferably 1620°C or lower. This makes it easier to melt the glass batch and reduces the manufacturing cost of the glass substrate. Also, B from the molten glass ２ O ３ or Na ２ The amount of volatilization of oxygen is reduced, making it less likely for a foreign layer to form on the molten glass surface, thus improving the homogeneity of the glass. Note that the high-temperature viscosity is 10 ２．５ The temperature in dPa·s corresponds to the melting temperature, and the lower this temperature, the better the meltability.

[0075] In this embodiment, the glass substrate is preferably formed by the overflow downdraw method. In the overflow downdraw method, a heat-resistant structure is used, which has a groove at its top, two sides extending along the groove and located on both sides of the groove, and a lower end where the lower parts of the two sides intersect. Molten glass is supplied to the groove at the top of such a heat-resistant structure and allowed to overflow from both sides, then the overflowed molten glass is allowed to flow down both sides of the heat-resistant structure and then merge at the lower end of the heat-resistant structure. The glass ribbon obtained in this way is stretched by pulling it downwards, a glass plate is cut from the glass ribbon, and a glass substrate is manufactured by processing such as cutting, edge processing, cleaning, inspection, and packaging. In the overflow downdraw method, the surface that will become the surface of the glass substrate does not come into contact with the heat-resistant structure and is formed in a free surface state, resulting in a forged surface. For this reason, glass substrates with good surface quality that are unpolished can be manufactured inexpensively, and thinning is also easy. Furthermore, glass substrates formed by the overflow downdraw method have a mating surface in the middle of the thickness direction.

[0076] In addition to the overflow downdraw method, glass substrates can also be formed using other methods such as the slot downdraw method, float method, and rollout method.

[0077] The shape of the glass substrate in this embodiment is not particularly limited, but it is preferably rectangular when used for semiconductor package substrate applications. The area of ​​the glass substrate in this case is preferably 50,000 mm². ２ The above is a more comfortable 80,000 mm ２ More than 100,000 mm ２ Above, a comfortable 200,000 mm ２ Above, a comfortable 220,000 mm ２ More specifically, 240,000 mm ２ In particular, 260,000 mm is preferred. ２That concludes the explanation. The length of each side of the glass substrate is preferably, for example, 300 mm x 300 mm or more and 1000 mm x 1000 mm or less, and may be, for example, 510 mm x 515 mm. By setting the area of ​​the glass substrate to such a value, the number of package substrates obtained when the substrate is finally separated into individual pieces can be increased.

[0078] The lengths of each side of the glass substrate in this embodiment are preferably (510±10mm)×(515±10mm), more preferably (510±5mm)×(515±5mm), more preferably (510±3mm)×(515±3mm), and most preferably (510±1mm)×(515±1mm), based on a standard of 510mm×515mm. By reducing the dimensional tolerance, the accuracy of positioning the glass substrate during wiring pattern formation can be improved, enabling finer wiring.

[0079] The thickness of the glass substrate in this embodiment is not particularly limited, but is preferably 0.03 mm or more, more preferably 0.05 mm or more, more preferably 0.1 mm or more, more preferably 0.2 mm or more, more preferably 0.3 mm or more, more preferably 0.35 mm or more, more preferably 0.4 mm or more, more preferably 0.45 mm or more, and particularly preferably 0.5 mm or more. The thicker the substrate, the less likely the glass substrate is to deform, which prevents damage to the glass substrate or semiconductor elements caused by deformation of the glass substrate during semiconductor element mounting. The thickness of the glass substrate is preferably 2 mm or less, more preferably 1.8 mm or less, more preferably 1.6 mm or less, more preferably 1.4 mm or less, more preferably 1.3 mm or less, more preferably 1.2 mm or less, and particularly preferably 1.1 mm or less. The thinner the substrate, the smaller the diameter of the through-holes can be made. By making the diameter of the through-holes smaller, the mounting density of semiconductor elements on the glass substrate can be increased, and fine wiring can be formed. On the other hand, if the board thickness is too thin, the rigidity of the substrate will be low, making it more prone to warping during mounting. The thickness of the glass substrate can be adjusted by controlling the flow rate and drawing speed during molding. Furthermore, processes such as slimming may be performed to adjust the thickness of the glass substrate.

[0080] The difference between the maximum and minimum distances between the first and second main surfaces of the glass substrate (TTV = Total Thickness Variation) is preferably 20 μm or less, more preferably 15 μm or less, more preferably 10 μm or less, more preferably 8 μm or less, more preferably 5 μm or less, more preferably 3 μm or less, more preferably 2 μm or less, and particularly preferably 1 μm or less. The smaller the TTV, the higher the surface accuracy and the easier it is to improve the accuracy of the processing. In particular, it is possible to improve the wiring accuracy, making high-density wiring possible. TTV can be measured, for example, by the Bow / Warp measuring device SBW-331ML / d manufactured by Kobelco Research Institute.

[0081] The amount of warpage of the glass substrate is preferably 60 μm or less, more preferably 55 μm or less, more preferably 50 μm or less, more preferably 45 μm or less, and particularly preferably 40 μm or less. The lower limit of the amount of warpage is not particularly limited, but may be, for example, 1 μm or more, or 5 μm or more. The smaller the amount of warpage, the easier it is to improve the accuracy of the processing. In particular, it is possible to improve the accuracy of the wiring, making high-density wiring possible. Here, "amount of warpage" refers to the sum of the absolute value of the maximum distance between the highest point and the least-squares focal plane and the absolute value of the distance between the lowest point and the least-squares focal plane, and can be measured, for example, by a Bow / Warp measuring device SBW-331ML / d manufactured by Kobelco Research Institute.

[0082] The relative permittivity of the glass substrate at 25°C and a frequency of 10 GHz is preferably 6.9 or less, more preferably 5.9 or less, more preferably 5.8 or less, and particularly preferably 5.7 or less. Furthermore, the relative permittivity of the glass substrate at 25°C and a frequency of 50 GHz is preferably 6 or less, more preferably 5.5 or less, more preferably 5.3 or less, more preferably 5 or less, more preferably 4.5 or less, and particularly preferably 4.2 or less. If the relative permittivity at 25°C and a frequency of 10 GHz, and the relative permittivity at 25°C and a frequency of 50 GHz are too high, when the glass substrate is used as an interposer or core substrate for high-frequency device applications, the transmission loss when electrical signals are transmitted to the glass substrate tends to be large. If the relative permittivity is within these values, the transmission loss can be reduced even when the glass substrate is used in high-frequency devices.

[0083] The dielectric loss tangent of the glass substrate at 25°C and a frequency of 10 GHz is preferably 0.01 or less, more preferably 0.005 or less, more preferably 0.003 or less, and particularly preferably 0.001 or less. Furthermore, the dielectric loss tangent of the glass substrate at 25°C and a frequency of 50 GHz is preferably 0.01 or less, more preferably 0.005 or less, more preferably 0.003 or less, and particularly preferably 0.001 or less. This makes it possible to reduce the transmission loss when electrical signals are transmitted to the glass substrate when the glass substrate is used as an interposer or core substrate for high-frequency device applications.

[0084] The linear transmittance of the glass substrate at a thickness of 400 nm to 1100 nm is preferably 80% or higher, more preferably 85% or higher, and particularly preferably 90% or higher. If there are few coloring components in the glass and the absorption coefficient is small in this wavelength range, the heat generated at the laser irradiation site will be reduced when laser light is irradiated to form a modified area on the glass substrate, making it less likely for defects such as cracks to occur. Alternatively, if the phase separation effect of the glass is small and the scattering coefficient is small in this wavelength range, the scattering of laser light can be suppressed, and the formation of a modified area on the glass substrate is promoted. It is not necessary for the above preferred transmittance range to be satisfied for the entire wavelength range of 400 nm to 1100 nm; it is sufficient if the above preferred transmittance range is satisfied for the wavelength of the laser light used. If the wavelength of the laser light used changes, it is preferable that the above preferred transmittance range be satisfied for the entire wavelength range of 400 nm to 1100 nm.

[0085] The glass substrate according to this embodiment is used in semiconductor packages, specifically in package substrates used for mounting semiconductor elements. Preferably, the glass substrate according to this embodiment is used to manufacture glass substrates having through holes (perforated glass substrates). Perforated glass substrates manufactured using the glass substrate according to this embodiment are particularly preferred for use as interposers or core substrates in semiconductor package substrates. The glass substrate according to this embodiment is suitable for forming through holes that are close to a straight shape, offers excellent productivity, has low relative permittivity and dielectric loss tangent, and is less prone to deformation during semiconductor element mounting, thus preventing damage to the glass substrate and semiconductor elements, making it suitable for applications such as interposers and core substrates.

[0086] [Second Embodiment] Next, a perforated glass substrate for semiconductor packaging (hereinafter referred to as "perforated glass substrate") according to the second embodiment of the present invention will be described. The perforated glass substrate according to this embodiment has through holes and is manufactured by forming through holes in the glass substrate (non-perforated glass substrate) according to the first embodiment. Therefore, the perforated glass substrate according to the second embodiment has the same glass composition and properties as the glass substrate according to the first embodiment.

[0087] Figure 2 is a top view showing a perforated glass substrate G1 according to this embodiment, and Figure 3 is a cross-sectional view of the perforated glass substrate G1 of Figure 2 taken along line A-A. As shown in Figures 2 and 3, the perforated glass substrate G1 according to this embodiment comprises a first main surface G1a, a second main surface G1b which is the opposite surface of the first main surface G1a, and a through hole 1 that penetrates between the first main surface G1a and the second main surface G1b. A first example of the through hole 1 is a constricted portion 1b in the center of the perforated glass substrate G1 in the thickness direction Z, with a diameter smaller than the diameter of the through hole 1 on the first main surface G1a and the second main surface G1b. In other words, the side surface 1a of the through hole 1 is inclined with respect to the thickness direction Z.

[0088] Figure 4 is a schematic cross-sectional view showing a first example of a through-hole 1 formed in a perforated glass substrate G1 according to one embodiment of the present invention. The diameter D1 of the through-hole 1 on the first main surface G1a and the diameter D2 of the through-hole on the second main surface G1b can be measured, for example, by observing the surface of the perforated glass substrate G1 with a transmission optical microscope and measuring the length from the image. The diameter D3 of the constricted portion 1b of the through-hole 1, the distance t1 between the first main surface G1a and the constricted portion 1b, and the distance t2 between the second main surface G1b and the constricted portion 1b can be measured by scribing the perforated glass substrate G1 so that the inner surface of the through-hole 1 is not exposed, observing it from the cross-sectional direction with a transmission optical microscope while focusing on the inside of the through-hole 1, and measuring the length from the image. As a transmission optical microscope, for example, a Nikon ECLIPSE LV100ND can be used.

[0089] The diameters D1 and D2 of the through-holes 1 in the first main surface G1a and the second main surface G1b are preferably 200 μm or less, more preferably 180 μm or less, more preferably 160 μm or less, more preferably 150 μm or less, more preferably 130 μm or less, more preferably 100 μm or less, more preferably 90 μm or less, more preferably 80 μm or less, more preferably 70 μm or less, more preferably 60 μm or less, and particularly preferably 50 μm or less. This allows for the formation of through-holes 1 at high density, and when the glass substrate G1 is used in the manufacture of core substrates or interposers, the wiring density can be increased. On the other hand, if the diameters D1 and D2 of the through-holes 1 in the first main surface G1a and the second main surface G1b are too small, when a conductive part is formed inside the through-holes 1 by plating, voids may be formed in the conductive material, which may cause a problem in which there is no electrical connection between the first main surface G1a and the second main surface G1b of the perforated glass substrate G1. Furthermore, the diameters D1 and D2 of the through holes 1 in the first main surface G1a and the second main surface G1b are preferably 5 μm or more, more preferably 10 μm or more, more preferably 15 μm or more, more preferably 20 μm or more, more preferably 21 μm or more, more preferably 22 μm or more, more preferably 23 μm or more, more preferably 24 μm or more, more preferably 25 μm or more, and particularly preferably 30 μm or more. This ensures that the above-mentioned problems are reliably prevented.

[0090] The ratio of the diameter D3 of the constricted portion 1b to the diameters D1 and D2 of the through-hole 1 in the first main surface G1a and the second main surface G1b (D1 / D3, D2 / D3) is preferably 99% or less, more preferably 95% or less, and particularly preferably 90% or less. This makes it easier to form a seed layer inside the hole by sputtering when forming a conductive portion inside the through-hole 1 by plating, and makes it easier to ensure adhesion of the plating. The ratio (D1 / D3, D2 / D3) is preferably 5% or more, more preferably 10% or more, more preferably 15% or more, more preferably 20% or more, more preferably 25% or more, more preferably 30% or more, more preferably 35% or more, more preferably 40% or more, more preferably 45% or more, more preferably 50% or more, more preferably 60% or more, more preferably 70% or more, more preferably 75% or more, more preferably 80% or more, and particularly preferably 90% or more. This makes it easier to fill the conductive material when forming a conductive part inside the through hole 1 by plating, and suppresses the problem of non-conductivity between the first main surface G1a and the second main surface G1b of the perforated glass substrate G1.

[0091] The average taper angle θ1 of the through hole 1 in the first example can be evaluated as follows. First, the taper angle θ1a of the side surface on the first main surface G1a side of the through hole 1, and the taper angle θ1b of the side surface on the second main surface G1b side of the through hole 1 are calculated using the following equations 1 and 2. θ1a = arctan((D1 - D3) / (2 × t1)) Equation 1 θ1b = arctan((D2 - D3) / (2 × t2)) Equation 2

[0092] Next, the average taper angle θ1 of the through hole 1 is calculated using the following equation 3: θ1 = (θ1a + θ1b) / 2 Equation 3

[0093] The average taper angle θ1 of the through-hole 1 is preferably 13° or less, more preferably 12° or less, more preferably 11° or less, more preferably 10° or less, more preferably 9° or less, more preferably 8° or less, more preferably 7° or less, more preferably 6° or less, more preferably 5° or less, more preferably 4.5° or less, and particularly preferably 4° or less. This allows for the formation of high-density through-holes 1, and when the perforated glass substrate G1 is used in the manufacture of core substrates or interposers, the wiring density can be increased. Furthermore, the average taper angle θ1 is preferably greater than 0°, more preferably 0.5° or more, more preferably 1° or more, more preferably 1.5° or more, more preferably 2° or more, more preferably 2.5° or more, and particularly preferably 3° or more. This makes it easier to fill the conductive material when forming a conductive part inside the through-hole 1 by plating, and suppresses the problem of non-conductivity between the first main surface G1a and the second main surface G1b of the glass substrate G1.

[0094] Figure 5 is a schematic cross-sectional view showing a second example of a through-hole 1 formed in a perforated glass substrate G1 according to one embodiment of the present invention. As shown in Figure 5, the through-hole 1 of the second example does not have a constricted portion in the center of the thickness direction Z of the perforated glass substrate G1. Furthermore, in the through-hole 1 of the second example, the diameter D1 of the through-hole 1 on the first main surface G1a is different from the diameter D2 of the through-hole 1 on the second main surface G1b, and the side surface 1a of the through-hole 1 is inclined with respect to the thickness direction Z.

[0095] The taper angle θ3 of the through hole 1 in the second example, which does not have a constricted section, is calculated by the following equation 4: θ3 = arctan((D1 - D2) / (2 × t)) Equation 4

[0096] In the second example, the diameters D1 and D2 and the taper angle θ3 of the through hole 1 are preferably within the same numerical range as the diameters D1 and D2 and the mean taper angle θ1 of the through hole 1 in the first example.

[0097] [Third Embodiment] Next, a perforated glass substrate for semiconductor packaging (hereinafter referred to as "perforated glass substrate") according to the third embodiment of the present invention will be described with reference to Figures 6 to 8. The perforated glass substrate according to this embodiment is a perforated glass substrate having non-through holes, and is manufactured by forming non-through holes in the glass substrate (non-perforated glass substrate) according to the first embodiment. Therefore, the perforated glass substrate according to the third embodiment has the same glass composition and properties as the glass substrate according to the first embodiment.

[0098] Figure 6 is a top view showing a perforated glass substrate G2 according to this embodiment, and Figure 7 is a cross-sectional view of the perforated glass substrate G2 of Figure 6 taken along line B-B. As shown in Figures 6 and 7, the perforated glass substrate G2 according to this embodiment comprises a first main surface G2a, a second main surface G2b which is the opposite surface of the first main surface G2a, and non-through holes 2 provided on the first main surface G2a and the second main surface G2b. The diameter of the non-through holes 2 decreases as they move inward in the thickness direction from the first main surface G2a and the second main surface G2b, and the bottom portion 2b of the non-through hole is provided at the point where the diameter is smallest. In other words, the side surface 2a of the non-through hole 2 is inclined with respect to the thickness direction Z. In this embodiment, non-through holes 2 are formed on both the first main surface G2a and the second main surface G2b, but non-through holes 2 may be formed on either the first main surface G2a or the second main surface G2b.

[0099] Figure 8 is a schematic cross-sectional view showing a non-through hole 2 formed in a perforated glass substrate G2 according to this embodiment. The diameter D4 of the non-through hole 2 on the first main surface G2a and the diameter D5 of the non-through hole 2 on the second main surface G2b can be measured in the same way as the diameters D1 and D2 of the through hole 1 in the second embodiment. The distance t3 between the first main surface G2a and the bottom 2b of the non-through hole, and the distance t4 between the second main surface G2b and the bottom 2b of the non-through hole can be measured in the same way as the distances t1 and t2 in the second embodiment.

[0100] The average taper angle θ2 of the non-through hole 2 can be evaluated as follows. First, the taper angle θ2a of the side surface on the first main surface G2a side of the non-through hole 2, and the taper angle θ2b of the side surface on the second main surface G2b side of the non-through hole 2 are calculated using the following equations 5 and 6. θ2a = arctan(D4 / (2×t3)) Equation 5 θ2b = arctan(D5 / (2×t4)) Equation 6

[0101] Next, the average taper angle θ2 of the non-through hole 2 is calculated using the following equation 7: θ2 = (θ2a + θ2b) / 2 Equation 7

[0102] [Fourth Embodiment] Next, a method for manufacturing a perforated glass substrate for semiconductor packaging according to the fourth embodiment of the present invention will be described with reference to Figures 9 to 11. As shown in Figure 9, the method for manufacturing a perforated glass substrate according to this embodiment comprises a preparation step S1 for preparing a glass substrate (non-perforated glass substrate) G0, a laser irradiation step S2 for irradiating the portion of the glass substrate G0 where through holes are to be formed with laser light to form a modified portion Gm, and an etching step S3 for etching the glass substrate G0 having the modified portion Gm to form perforated glass substrates G1 and G2 having holes.

[0103] In preparation step S1, a glass substrate G0 according to the first embodiment of the present invention is prepared. The glass substrate G0 may be prepared, for example, by cutting a glass plate formed by the overflow downdraw method to a predetermined size. Alternatively, a glass plate formed by other methods such as the slot downdraw method, float method, or rollout method may be cut to a predetermined size.

[0104] In the laser irradiation process S2, as shown in Figure 10, the glass substrate G0 is placed flat with the second main surface G0b facing downwards. The glass substrate G0 may also be placed on a surface plate (not shown), for example. The irradiation unit of the laser irradiation device 3 is positioned away from the first main surface G0a of the glass substrate G0 so as to face the first main surface G0a. The irradiation unit of the laser irradiation device 3 is configured to be movable in three dimensions by a drive device (not shown).

[0105] Next, the laser irradiation device 3 irradiates the first main surface G0a of the glass substrate G0 with laser light 3a perpendicular to it. It is preferable that the laser irradiation device 3 irradiates with a pulsed laser. With a pulsed laser, the glass substrate G0 can be heated efficiently by increasing the energy per pulse, and the glass substrate G0 can be prevented from being damaged by heat diffusion by shortening the pulse duration. It is preferable that the laser light 3a is a picosecond laser or a femtosecond laser, and the pulse width is preferably, for example, 50 fs or more and 100 ps or less. It is also preferable that the energy per pulse of the laser light 3a is, for example, 10 μJ or more and 300 μJ or less.

[0106] It is preferable to use a wavelength of laser light 3a between 400 nm and 1100 nm. For example, the wavelength of laser light 3a is 515 nm or 1030 nm.

[0107] The laser irradiation device 3 preferably shapes the laser beam 3a into a Gaussian beam shape or a Bessel beam shape using an optical system (not shown) including, for example, an axicon lens, and it is particularly preferable to use a Bessel beam shape. By shaping the laser beam 3a into a Bessel beam shape, a modified portion Gm can be formed over the entire thickness direction of the glass substrate G0 with a single laser irradiation, thereby shortening the time required to form the modified portion Gm. In this embodiment, the focal length of the laser beam 3a is, for example, 0.1 mm or more and 10 mm or less. The spot diameter of the laser beam 3a is, for example, 0.1 μm or more and 10 μm or less.

[0108] When the laser irradiation device 3 irradiates the glass substrate G0 with laser light 3a toward the first main surface G0a, modified portions Gm are formed on the glass substrate G0. By repeatedly moving the irradiation position of the laser light 3a relative to the glass substrate G0 and irradiating with the laser light 3a, multiple modified portions Gm are formed on the glass substrate G0. In this embodiment, each time the laser irradiation device 3 irradiates with one pulse of laser light 3a, the irradiation position of the laser light 3a relative to the glass substrate G0 is moved. In other words, each of the multiple modified portions Gm is formed by a single pulse of laser light 3a.

[0109] In etching step S3, the glass substrate G0, on which the modified portion Gm was formed in the laser irradiation step S2 described above, is immersed in an etching solution to remove the modified portion Gm and form through holes 1. The type of etching solution is not particularly limited as long as the etching rate of the modified portion Gm is higher than the etching rate of the unmodified portion, for example, an aqueous HF solution, an aqueous NaOH solution, or an aqueous KOH solution can be used. As an etching solution, an aqueous HF solution is particularly preferred because it has a high etching rate and can shorten the time of etching step S3. In addition, HCl and H are added to the aqueous HF solution. ２ SO ４ HNO ３ One or more acids may be added to form a mixed aqueous solution. A surfactant may also be added. In etching step S3, after the modified portion Gm is removed to form the through hole 1, the diameter of the through hole 1 may be widened by etching the unmodified portion around the modified portion Gm until the diameter of the through hole 1 reaches a desired value.

[0110] The temperature of the etching solution is not particularly limited, but it is preferable to lower the temperature of the etching solution in order to reduce the average taper angle θ1. When using an etching solution containing HF, the upper limit of the etching solution temperature is preferably 30°C or lower, more preferably 20°C or lower, more preferably 10°C or lower, and particularly preferably 5°C or lower. Lowering the temperature of the etching solution lowers the etching rate, which reduces the amount of residue generated in the etching process S3, and makes it easier to scrape out the residue from inside the hole. As a result, etching at the tip of the hole is less likely to be hindered by residue during the formation of the through hole 1, and the average taper angle θ1 of the through hole 1 tends to become smaller. The lower limit of the etching solution temperature is preferably 0°C or higher. By setting the temperature in this way, the possibility of the etching solution freezing can be reduced.

[0111] The concentration of the etching solution is not particularly limited and may be changed as appropriate to obtain the desired shape of the through-hole 1. For example, the concentration of the etching solution may be changed during the formation of the through-hole 1. During the etching process S3, the concentration of the etching solution changes, so it is preferable to circulate or replace the etching solution to maintain a constant concentration.

[0112] In etching step S3, it is preferable to stir the etching solution or apply ultrasonic waves to the etching solution. Alternatively, the glass substrate G0 may be agitated in the etching solution. This makes it easier to scrape out residue from inside the holes, and the average taper angle θ1 of the through-hole 1 tends to decrease.

[0113] Furthermore, an alkaline chemical solution may be used as the etching solution to create a through-hole 1 that is close to a straight shape; for example, an aqueous solution of NaOH or an aqueous solution of KOH can be used. The etching solution may also be a mixed aqueous solution by adding one or more alkaline hydroxides such as NaOH and KOH, or a surfactant may be added. The concentration of the etching solution in this case is not particularly limited and may be changed as appropriate to obtain the desired shape of the through-hole 1, but it is preferable to increase the alkali concentration of the etching solution in order to shorten the etching time required for the formation of the through-hole. For example, in the case of an aqueous solution of NaOH, it is preferable to use an aqueous solution containing 30% by mass or more of NaOH, and it is more preferable to use an aqueous solution containing 40% by mass or more of NaOH. Furthermore, the concentration of the etching solution may be changed during the formation of the through-hole 1. Note that since the concentration of the etching solution changes during the execution of etching step S3, it is preferable to circulate or replace the etching solution to keep the concentration of the etching solution constant.

[0114] The temperature of the etching solution is not particularly limited, but it is preferable to raise the temperature of the etching solution in order to shorten the etching time required for the formation of through holes. Therefore, when using an etching solution containing NaOH, the lower limit of the etching solution temperature is preferably 70°C or higher, more preferably 80°C or higher, more preferably 90°C or higher, more preferably 100°C or higher, more preferably 105°C or higher, more preferably 110°C or higher, more preferably 115°C or higher, and particularly preferably 120°C or higher. The upper limit of the etching solution temperature is preferably 140°C or lower, more preferably 135°C or lower, and particularly preferably 130°C or lower. By setting the temperature in this way, temperature unevenness in the etching solution can be reduced, and the TTV of the glass substrate after etching can be lowered. Furthermore, by increasing the pressure inside the etching container, the boiling point of the etching solution can be raised, and the glass substrate can be etched at a temperature above the boiling point of the etching solution under atmospheric pressure.

[0115] Figure 11 is a schematic diagram for comparing the glass substrate G0 before etching process S3 and the perforated glass substrate G1 after etching process S3. In Figure 11, the glass substrate G0 before etching process S3 is shown by a dashed line. As shown in Figure 11, in etching process S3, the first main surface G0a, the second main surface G0b, or both the first main surface G0a and the second main surface G0b are etched, so the thickness t of the perforated glass substrate G1 after through-hole formation is smaller than the thickness t0 of the glass substrate G0 before through-hole formation.

[0116] Furthermore, in the perforated glass substrate G1 according to this embodiment, since through holes 1 are formed by the etching process S3, at least the side surface 1a of the through hole 1 (inside the through hole 1) and one of the main surfaces are etched surfaces. As a result, the inside of the through hole 1 and one of the main surfaces have excellent surface properties, are free from fine cracks, and have high strength. Therefore, by using the perforated glass substrate G1 according to this embodiment as a core substrate or interposer, a package substrate that is resistant to damage can be obtained. On the other hand, when through holes are formed in the glass substrate G0 by methods such as laser ablation, the surface properties inside the through holes are poor, and fine cracks are more likely to occur, resulting in lower strength.

[0117] In etching step S3, if etching is performed from both the first main surface G0a and the second main surface G0b of the glass substrate G0, the through hole 1 of the first example described above, that is, the through hole 1 having a constricted portion 1b, is formed. On the other hand, if etching step S3 is performed with a protective film attached to either the first main surface G0a or the second main surface G0b, etching is performed only from the main surface without the protective film, and the through hole 1 of the second example described above, that is, the through hole 1 without a constricted portion 1b, is formed.

[0118] The present invention will be described below based on examples. Note that the following examples are merely illustrative. The present invention is not limited in any way to the following examples.

[0119] Tables 1 to 3 show the glass composition and glass properties of the examples of the present invention (samples No. 1 to 9).

[0120] First, glass batches prepared with glass raw materials to achieve the glass composition shown in the table were placed in a platinum crucible and melted at 1550-1650°C for 24 hours. During the melting of the glass batches, a platinum stirrer was used to stir and homogenize them. Next, the molten glass was poured onto a carbon plate, formed into a plate shape, and then slowly cooled at a temperature near the annealing point for 30 minutes. For each obtained sample, the density, average thermal expansion coefficient CTE in the temperature range of 30-380°C, Young's modulus, strain point Ps, annealing point Ta, softening point Ts, and high-temperature viscosity 10 were recorded. ４．０ Temperature and high-temperature viscosity at dPa·s 10 ３．０ Temperature and high-temperature viscosity at dPa·s 10 ２．５ Temperature, liquidus temperature TL, and viscosity at liquidus temperature TL in dPa·s (log) １０ ηTL, HF etching rate, relative permittivity, and dielectric loss tangent were evaluated.

[0121]

[0122]

[0123]

[0124] The density was measured using the well-known Archimedes method.

[0125] The average thermal expansion coefficient CTE in the temperature range of 30 to 380°C is the value measured using a dilatometer.

[0126] Young's modulus is a value measured using a well-known resonance method.

[0127] The strain point Ps, annealing point Ta, and softening point Ts were measured according to the ASTM C336 and C338 methods.

[0128] High temperature viscosity 10 ４．０ dPa·s, 10 ３．０ dPa·s, 10 ２．５ The temperature in dPa·s was measured using the platinum ball pulling method.

[0129] The liquidus temperature TL is the temperature at which crystals precipitate after the glass powder that passes through a standard 30-mesh (500 μm) sieve and remains in a 50-mesh (300 μm) sieve is placed in a platinum boat and held in a temperature gradient furnace for 24 hours.

[0130] liquidus viscosity log １０ ηTL is the viscosity of the glass at the liquidus temperature TL, measured using the platinum ball pulling method.

[0131] The HF etching rate is the value measured using the method described above (Method for measuring HF etching rate).

[0132] The relative permittivity and dielectric loss tangent were measured using the capacitance method at a frequency of 0.001 GHz and the resonator method at frequencies from 1 to 100 GHz.

[0133] Next, through-holes were formed in glass substrate samples No. 1 to 5 and 8 using the following method. First, the glass substrate samples were cut into a rectangular shape of 40 mm x 20 mm, and then slimmed down to a predetermined thickness t0. A picosecond pulsed laser, shaped into a Vessel beam, was irradiated onto these glass substrate samples from the first main surface side with an irradiation position spacing of approximately 200 μm, forming approximately 8,000 modified areas on the glass substrate.

[0134] For the glass substrate samples with etching times of 15 minutes, 30 minutes, and 45 minutes, the plate thickness t0 was adjusted so that the holes were completely through and the diameter of the constricted portion was 1 μm after the respective etching times had elapsed.

[0135] Next, the glass substrate sample was etched under the following conditions. The glass substrate sample was placed in a polypropylene test tube containing the etching solution, and etching was performed by applying ultrasound to the etching solution. During this process, a PTFE jig was used to fix the glass substrate sample 10 mm away from the bottom of the test tube. An aqueous solution containing 2.5 mol / L of HF and 1.0 mol / L of HCl was used as the etching solution. The temperature of the etching solution was set to 10°C. To prevent the temperature from rising during ultrasound application, a chiller was used to circulate the water in the ultrasonic device and maintain the water temperature at 10°C. An ultrasonic cleaner (VS-100III: manufactured by AS ONE Corporation) was used to apply ultrasonic vibrations, and 28 kHz ultrasound was applied to the etching solution.

[0136] The glass substrate samples obtained by this method had through-holes with constricted sections formed inside. The average taper angle θ1 of these through-holes was determined by the method described above.

[0137] Tables 4 to 6 show the etching time, the thickness of the glass substrate sample before etching, the thickness of the glass substrate sample after etching, the etching rate, and the shape of the through-holes.

[0138] The etching rate was calculated by dividing the reduction in plate thickness due to etching (plate thickness of the glass substrate before etching - plate thickness of the glass substrate after etching) by the etching time. Note that the "etching rate" in this embodiment is a different parameter from the "HF etching rate," and was measured to confirm that the etching characteristics of the glass substrate sample do not change easily even when the etching time is varied.

[0139]

[0140]

[0141]

[0142] Next, a picosecond pulsed laser, shaped into a Vessel beam, was irradiated onto a glass substrate sample cut into a rectangular shape of 50 mm x 50 mm from the first main surface side, with the irradiation positions spaced approximately 200 μm apart, to form approximately 10,000 modified areas on the glass substrate. For this glass substrate, an aqueous solution containing 1.5 mol / L of HF and 0.2 mol / L of HCl was used as the etching solution, and the etching solution temperature was set to 33°C. Etching was performed by agitating the glass in the etching solution.

[0143] The perforated glass substrate samples obtained by this method had through-holes with constricted sections inside. The average taper angle θ1 of the through-holes was determined by the method described above.

[0144] Table 7 shows the etching time, the thickness of the glass substrate sample, the thickness of the perforated glass substrate sample, and the shape of the through-holes.

[0145]

[0146] Next, a glass substrate sample cut into a rectangular shape of 50 mm x 50 mm was irradiated from the first main surface side with a picosecond pulsed laser shaped into a Vessel beam, with the irradiation positions spaced approximately 200 μm apart, to form approximately 10,000 modified areas on the glass substrate. For this glass substrate, an aqueous solution containing 30 wt% NaOH was used as the etching solution, the etching solution temperature was set to 80°C, and etching was performed by agitating the glass in the etching solution.

[0147] The perforated glass substrate samples obtained by this method had through-holes or non-through-holes with constricted sections inside. The average taper angle θ1 of the through-holes or the average taper angle θ2 of the non-through-holes was determined by the method described above.

[0148] Table 8 shows the etching time, the thickness of the glass substrate sample, the thickness of the perforated glass substrate sample, and the shape of the through-holes. Table 9 shows the etching time, the thickness of the glass substrate sample, the thickness of the perforated glass substrate sample, and the shape of the non-through-holes. If a through-hole is formed, the distance t1 between the first main surface and the constricted portion, and the distance t2 between the second main surface and the constricted portion are indicated. If a non-through-hole is formed, the hole depth is indicated as the distance t3 between the first main surface and the bottom of the non-through-hole on the first main surface side, and the distance t4 between the second main surface and the bottom of the non-through-hole on the second main surface side.

[0149]

[0150]

[0151] Next, a glass substrate sample cut into a rectangular shape of 510 mm x 515 mm was irradiated from the first main surface side with a picosecond pulsed laser shaped into a Vessel beam, with the irradiation positions spaced approximately 200 μm apart, to form approximately 100,000 modified areas on the glass substrate. For this glass substrate, an aqueous solution containing 48 wt% NaOH was used as the etching solution, and the etching solution temperature was set to 100°C. Etching was performed by agitating the glass in the etching solution.

[0152] The perforated glass substrate samples obtained by this method had through-holes with constricted sections inside. The average taper angle θ1 of the through-holes was determined by the method described above.

[0153] Table 10 shows the etching time, the thickness of the glass substrate sample, the thickness of the perforated glass substrate sample, and the shape of the through-holes.

[0154]

[0155] Table 1 shows that the glass substrate samples of this embodiment exhibited low temperatures at high-temperature viscosity and excellent productivity. Furthermore, a low coefficient of thermal expansion was observed, making substrate deformation less likely during semiconductor device mounting. This prevents damage to the glass substrate and semiconductor devices during mounting. Tables 2 and 3 also show that the glass substrate samples of this embodiment exhibited low relative permittivity and dielectric loss tangent. Sample No. 8, in particular, showed very low relative permittivity and dielectric loss tangent. This reduces high-frequency signal transmission loss when the glass substrate is used as a core substrate or interposer in a package substrate. Tables 4-10 also show that the glass substrate samples with through-holes manufactured using the glass substrate samples of this embodiment had a small average taper angle, resulting in through-holes that were nearly straight. Therefore, the glass substrate samples of this embodiment are suitable for use as core substrates or interposers in package substrates used for semiconductor device mounting.

[0156] G0 Non-perforated glass substrate G0a First main surface G0b Second main surface G1 Perforated glass substrate G1a First main surface G1b Second main surface Gm Modified area Z Thickness direction 1 Through hole 1a Side of through hole 1b Narrowed area 2 Non-through hole 2a Side of non-through hole 2b Bottom of non-through hole 3a Laser beam D1 Diameter of through hole on the first main surface D2 Diameter of through hole on the second main surface D3 Diameter of through hole in the narrowed area D4 Diameter of non-through hole on the first main surface D5 Diameter of non-through hole on the second main surface θ1 Average taper angle of through hole θ2 Average taper angle of non-through hole

Claims

1. A perforated glass substrate for semiconductor packaging comprising a first main surface, a second main surface which is the opposite surface of the first main surface, and a through hole penetrating between the first main surface and the second main surface, wherein the glass composition is SiO2 in mol%. ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-30%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging, characterized by containing 0-0.1% O, 0-20% MgO, 0-15% CaO, 0-10% SrO, and 0-10% BaO.

2. As a glass composition, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B ２ O ３ 0 to 30%, Li ２ O 0 to 0.1%, Na ２ O 0 to 0.1%, K ２ O 0 to 0.1%, MgO 0 to 10%, CaO 0 to 10%, SrO 0 to 10%, BaO 0 to 10%, the porous glass substrate for a semiconductor package according to claim 1.

3. As for the glass composition, in mol%, SiO ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 0-20%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 0-10% MgO, 0-10% CaO, 0-10% SrO, and 0-10% BaO.

4. As for the glass composition, in mol%, SiO ２ 55-71.5%, Al ２ O ３ 5-14%, B ２ O ３ 0-8%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 0-7% MgO, 0-10% CaO, 0-2.4% SrO, and 0-4.5% BaO.

5. As for the glass composition, in mol%, SiO ２ 55-71.5%, Al ２ O ３ 5-14%, B ２ O ３ 3-8%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 0-5% MgO, 3.5-10% CaO, 0-4% SrO, and 0-1% BaO.

6. As for the glass composition, in mol%, SiO ２ 65-71.5%, Al ２ O ３ 5-14%, B ２ O ３ 0-10%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 0-5% MgO, 5-10% CaO, 0-3% SrO, and 0-3% BaO.

7. As for the glass composition, in mol%, SiO ２ 65-75%, Al ２ O ３ 5-14%, B ２ O ３ 5-15%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 4-8% MgO, 0-3% CaO, 1-5% SrO, and 0-2% BaO.

8. As for the glass composition, in mol%, SiO ２ 55-65%, Al ２ O ３ 5-14%, B ２ O ３ 5-15%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 5-10% MgO, 5-10% CaO, 0-3% SrO, and 0-5% BaO.

9. As for the glass composition, in mol%, SiO ２ 55-85%, Al ２ O ３ 1-15%, B ２ O ３ 15-30%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0-0.1% O, 0-10% MgO, 0-10% CaO, 0-10% SrO, and 0-10% BaO.

10. As for the glass composition, in mol%, SiO ２ 55-65%, Al ２ O ３ 5-15%, B ２ O ３ 0-10%, Li ２ O 0-0.1%, Na ２ O 0-0.1%, K ２ O 0-0.1%, MgO 15-20%, CaO 5-15%, SrO 0-5%, BaO 0-5%, ZrO ２ 0.1-5%, Y ２ O ３ A perforated glass substrate for semiconductor packaging according to claim 1, containing 0.1 to 10%.

11. As for the glass composition, in mol% TiO ２ A perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, further containing 0 to 0.01%.

12. The average coefficient of thermal expansion in the temperature range of 30 to 380°C is 2.8 × 10⁻⁶. －６ ~4.5 x 10 －６ A perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the temperature is / °C.

13. A perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the Young's modulus is 70 GPa or higher.

14. The perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the thickness of the glass substrate is 0.03 mm or more and 2 mm or less, the TTV of the glass substrate is 20 μm or less, and the warpage of the glass substrate is 60 μm or less.

15. A perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the HF etching rate is 1.5 μm / min or less.

16. The perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the side surface of the through hole is inclined with respect to the thickness direction of the plate, and the average taper angle of the side surface is greater than 0° and 13° or less.

17. The perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the through-hole has a constricted portion in the center of the glass substrate in the thickness direction, the constricted portion having a smaller diameter than the diameter of the through-hole on the first main surface and the second main surface, and the diameter of the constricted portion is 50% or more and 99% or less of the diameter of the through-hole on the first main surface and the diameter of the through-hole on the second main surface.

18. The perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein the diameter of the through hole on the first main surface is 5 μm or more and 200 μm or less, and the diameter of the through hole on the second main surface is 5 μm or more and 200 μm or less.

19. The perforated glass substrate for semiconductor packaging according to any one of claims 1 to 10, wherein at least the inner surface of the through-hole is an etched surface.

20. A glass substrate used in the manufacture of a perforated glass substrate for a semiconductor package having through holes. As the glass composition, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B ２ O ３ 0 to 30%, Li ２ O 0 to 0.1%, Na ２ O 0 to 0.1%, K ２ O 0 to 0.1%, MgO 0 to 20%, CaO 0 to 15%, SrO 0 to 10%, BaO 0 to 10%, and characterized by a glass substrate for a semiconductor package.

21. A method for manufacturing a perforated glass substrate for semiconductor packaging, comprising: a preparation step of preparing the glass substrate described in claim 20; a laser irradiation step of irradiating the portion of the glass substrate where through holes are to be formed with laser light to form a modified portion; and an etching step of etching the glass substrate having the modified portion to form through holes.

22. A perforated glass substrate for a semiconductor package, comprising a first main surface, a second main surface opposite to the first main surface, and a non-through hole formed between the first main surface and the second main surface, wherein the glass composition contains, in mol%, SiO ２ 55 to 85%, Al ２ O ３ 1 to 15%, B ２ O ３ 0 to 30%, Li ２ O 0 to 0.1%, Na ２ O 0 to 0.1%, K ２ O 0 to 0.1%, MgO 0 to 20%, CaO 0 to 15%, SrO 0 to 10%, BaO 0 to 10%, and is characterized by being a perforated glass substrate for a semiconductor package.

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