Glass substrate, support glass substrate, laminate, production method for laminate, and production method for semiconductor package

Abstract

Provided is a glass substrate that has a prescribed thermal expansion coefficient and high thermal stability and does not experience glass phase separation.　This glass substrate: has a glass composition that is 60–80 mol% SiO2, 5–15 mol% Al2O3, 5–20 mol% B2O3, 1–10 mol% MgO, 0.1–3.9 mol% CaO, and 1–10 mol% SrO, the molar ratio of Al2O3 / B2O3 being 0.5–1; and has an average thermal expansion coefficient of less than 32×10-7 / °C within the temperature range of 20°C–260°C.

Description

Glass substrate, supporting glass substrate, laminate, laminate manufacturing method and semiconductor package manufacturing method

[0001] The present invention relates to a glass substrate, particularly to a glass substrate suitable as a supporting glass substrate for use in a semiconductor package, and also to a laminate using the supporting glass substrate, a manufacturing method thereof, and a manufacturing method of a semiconductor package.

[0002] In recent years, in the field of semiconductor devices, device integration has become increasingly high and device size has become smaller, which has led to a demand for packaging technologies for highly integrated devices.

[0003] The packaging technology is used in, for example, portable electronic devices such as smartphones, notebook personal computers, and PDAs (Personal Data Assistance), as well as fan-out WLP (Wafer Level Package) and PLP (Panel Level Package), or CoWoS (Chip on Wafer on Substrate) for AI (Artificial Intelligence) and HPC (High Performance Computing) applications.

[0004] Furthermore, in recent years, packaging technology has also been adopted for high-density packaging, such as three-dimensional packaging that combines fan-out WLP, PLP, and CoWoS with SoIC (System on Integrated Chips). Note that hereinafter in this specification, WLP and PLP will be collectively referred to as WLP, etc.

[0005] The manufacturing process for these packages includes, for example, arranging multiple semiconductor chips on a supporting glass substrate, molding them with a resin sealing material to form a processed substrate, and then performing processes such as wiring one surface of the processed substrate and forming solder bumps.

[0006] In the manufacturing process of these semiconductor packages, a technique for bonding, for example, a silicon wafer or an interposer to a glass substrate is required, and this glass substrate is required to function as a supporting glass substrate. Specifically, the supporting glass substrate is bonded to the silicon substrate via a release layer such as resin, and the silicon substrate is embedded in resin. Thereafter, the supporting glass substrate is peeled off from the resin-embedded silicon substrate by irradiating with ultraviolet light.

[0007] In the manufacturing process of this package, in order to prevent alkali metal ions from diffusing into the silicon substrate, it is preferable to use glass with a low content of alkali metal oxides for the supporting glass substrate (see Patent Document 1).

[0008] Japanese Patent Application Laid-Open No. 2022-27842

[0009] As mentioned above, in the manufacturing process of semiconductor packages, the supporting glass substrate is bonded to the silicon substrate via a release layer such as a resin. However, if the thermal expansion coefficients of the glass substrate and the silicon substrate do not match, the difference in the thermal expansion coefficients between them may cause warping of the glass substrate. In particular, the thinner the glass substrate, the more likely it is that warping will occur in the glass substrate. For this reason, the glass substrate has an average thermal expansion coefficient of 32×10 between 20 and 260°C. －７ / °C or less may be required.

[0010] However, the average thermal expansion coefficient of glass between 20 and 260°C is 32 × 10 －７ / °C, defects in the glass are likely to occur. Specifically, when a glass composition is designed so as to reduce the average thermal expansion coefficient of the glass, the thermal stability of the glass may decrease, making it more likely to undergo phase separation. Phase separation in the glass may result in a decrease in the mechanical strength of the glass, a local deterioration in weather resistance, or a local decrease in transmittance.

[0011] The present invention has been made in view of the above circumstances, and its technical object is to provide a glass substrate that has a predetermined thermal expansion coefficient, high thermal stability, and is free from glass phase separation.

[0012] As a result of extensive efforts and repeated investigations, the present inventors have found that the above technical problems can be solved by strictly controlling the range of the glass composition of the glass substrate, and have proposed this finding as the present invention.

[0013] That is, the glass substrate of embodiment 1 has a glass composition containing, in mol %, SiO ２ 60-80%, Al ２ O ３ 5-15%, B ２ O ３ 5 to 20%, MgO 1 to 10%, CaO 0.1 to 3.9%, SrO 1 to 10%, and the molar ratio of Al ２ O ３ / B ２ O ３ is 0.5 to 1, and the average thermal expansion coefficient in the temperature range of 20°C to 260°C is 32 × 10 －７ / °C or less. ２ O ３ / B ２ O ３ " is Al ２ O ３ The content of B ２ O ３ The "average coefficient of thermal expansion in the temperature range of 20°C to 260°C" is a value measured with a dilatometer.

[0014] The glass substrate of the second embodiment is the same as that of the first embodiment except that the glass composition is a molar ratio (SiO ２ +Al ２ O ３ ) / (B ２ O ３ +MgO + CaO + SrO + BaO) is preferably 2.8 to 5. ２ +Al ２ O ３ ) / (B ２ O ３ + MgO + CaO + SrO + BaO) is SiO ２ and Al ２ O ３ The total amount of B ２ O ３ , MgO, CaO, SrO, and BaO.

[0015] The glass substrate of the third aspect is the same as that of the first or second aspect, except that the glass composition is a molar ratio (SiO ２ +Al ２ O ３ ) / (MgO+CaO+SrO+BaO) is preferably 6 to 10. ２ +Al ２ O ３ ) / (MgO+CaO+SrO+BaO) is SiO ２ and Al ２ O ３ This refers to the value obtained by dividing the total amount of MgO, CaO, SrO, and BaO by the total amount of MgO, CaO, SrO, and BaO.

[0016] The glass substrate of Aspect 4 is any one of Aspects 1 to 3, wherein the average thermal expansion coefficient in the temperature range of 20°C to 260°C is 30×10 －７ / ° C. Here, the "average coefficient of thermal expansion in the temperature range of 20° C. to 260° C." is a value measured with a dilatometer.

[0017] The glass substrate of Aspect 5 is any one of Aspects 1 to 4, and preferably has a glass composition containing 0.1% or less alkali metal oxide in mol %.

[0018] The glass substrate of Aspect 6 is any one of Aspects 1 to 5, and preferably has a glass composition containing 0.1% or less BaO in mol %.

[0019] The glass substrate of Aspect 7 is preferably not crystallized glass in any one of Aspects 1 to 6. Here, "crystallized glass" refers to a composite material in which crystals are precipitated from the interior or surface of glass, and crystal peaks can be confirmed in an X-ray diffraction pattern. In this case, the crystals are clearly distinguished from devitrified particles that are unintentionally precipitated.

[0020] The glass substrate of Aspect 8 is preferably any one of Aspects 1 to 7, and has a Young's modulus of 65 GPa or more. Here, "Young's modulus" refers to a value measured by a bending resonance method.

[0021] The glass substrate of Aspect 9 is any one of Aspects 1 to 8, wherein the liquidus viscosity is 10 ３．５ Preferably, the viscosity is dPa·s or more. Here, the "liquidus viscosity" is the viscosity at the liquidus temperature, and is measured by the platinum ball pulling method. The "liquidus temperature" can be calculated by placing glass powder that has passed through a standard sieve of 30 mesh (500 μm) and remains on a 50 mesh (300 μm) sieve in a platinum boat, and then holding the boat in a temperature gradient furnace for 24 hours to measure the temperature at which crystals precipitate or phase separation occurs. The liquidus viscosity is an index of moldability, and the higher the liquidus viscosity, the better the moldability.

[0022] The glass substrate of Aspect 10 is a glass substrate of any one of Aspects 1 to 9, ２．５ It is preferable that the temperature at 10 dPa·s is less than 1650°C. ２．５ The "temperature at 10 dPa·s" is measured by the platinum ball pull-up method. ２．５ The temperature at dPa·s corresponds to the melting temperature, and the lower this temperature is, the more improved the melting property is, and the more likely it is that undissolved crystalline foreign matter will be prevented from precipitating from the molten glass during melting.

[0023] The glass substrate of Aspect 11 is preferably any one of Aspects 1 to 10, and has a transmittance, including reflection loss, of 5% or more at 254 nm, calculated based on a thickness of 1 mm.

[0024] The supporting glass substrate of Aspect 12 is the glass substrate of any one of Aspects 1 to 11, and is preferably a supporting glass substrate used to support a processed substrate.

[0025] The supporting glass substrate of Aspect 13 is preferably the same as that of Aspect 12, having a wafer shape with a diameter of 100 to 500 mm, a thickness of less than 2.0 mm, a total thickness variation (TTV) of 5 μm or less, and a warpage of 60 μm or less. Here, the "total thickness variation (TTV)" can be measured, for example, using a Bow / Warp measuring device SBW-331ML / d manufactured by Kobelco Research Institute, Inc. The "warpage amount" refers to the sum of the absolute value of the maximum distance between the highest point and the least-squares focal plane on the entire supporting glass substrate and the absolute value of the distance between the lowest point and the least-squares focal plane, and can be measured, for example, using a Bow / Warp measuring device SBW-331ML / d manufactured by Kobelco Research Institute, Inc.

[0026] The supporting glass substrate of aspect 14 is preferably, in aspect 12, a substantially rectangular shape with at least one side of 300 mm or more, a thickness of less than 2.0 mm, a total thickness variation (TTV) of 5 μm or less, and a warpage of 60 μm or less.

[0027] The supporting glass substrate of Aspect 15 is preferably used for supporting a fan-out type wafer level package or a fan-out type panel level package in any one of Aspects 12 to 14.

[0028] The supporting glass substrate of Aspect 16 is preferably used for supporting a semiconductor for back grinding in any one of Aspects 12 to 14.

[0029] The laminate of Aspect 17 includes at least a processed substrate and a supporting glass substrate used to support the processed substrate, and it is preferable that the supporting glass substrate is the supporting glass substrate of any one of Aspects 12 to 15.

[0030] The laminate of Aspect 18 is preferably the laminate of Aspect 17, further comprising at least a semiconductor chip molded with an encapsulant.

[0031] The method for manufacturing the laminate of Aspect 19 preferably includes the steps of preparing a support glass substrate of any one of Aspects 12 to 15, preparing a processed substrate, and stacking the support glass substrate and the processed substrate to obtain a laminate.

[0032] The method for manufacturing a semiconductor package of Aspect 20 preferably includes the steps of preparing the laminate of Aspect 17 or Aspect 18, and performing a processing treatment on the processing substrate.

[0033] The method for manufacturing a semiconductor package of Aspect 21 is preferably the same as Aspect 20, and further includes a step of forming wiring on one surface of the processed substrate.

[0034] A method for manufacturing a semiconductor package according to aspect 22 is preferably the same as that according to aspect 20 or 21, in which the processing step includes a step of forming solder bumps on one surface of the processed substrate.

[0035] According to the present invention, it is possible to provide a glass substrate that has a predetermined thermal expansion coefficient, high thermal stability, and is free from glass phase separation.

[0036] The glass substrate of the present invention has a glass composition containing, in mol %, SiO ２ 60-80%, Al ２ O ３ 5-15%, B ２ O ３ 5 to 20%, MgO 1 to 10%, CaO 0.1 to 3.9%, SrO 1 to 10%, and the molar ratio of Al ２ O ３ / B ２ O ３ is 0.5 to 1. The reasons for limiting the content of each component as described above are as follows. In the description of the content of each component, % indicates mol % unless otherwise specified. Furthermore, unless otherwise specified, in this specification, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively.

[0037] SiO ２ is the main component that forms the skeleton of glass and is a component that significantly reduces the average thermal expansion coefficient. It is also a component that increases Young's modulus and acid resistance. However, SiO ２If the content of SiO is too high, the high-temperature viscosity increases, which tends to decrease the melting property and moldability, and in addition, devitrified crystals such as cristobalite tend to precipitate, which tends to increase the liquidus temperature. ２ The content is 60 to 80%, preferably 62 to 78%, 64 to 76%, 65 to 75%, and particularly preferably 66 to 74%.

[0038] Al ２ O ３ is a component that forms a glass skeleton and reduces the average thermal expansion coefficient. It is also a component that increases the Young's modulus. ２ O ３ If the content of B is too high, crystals such as mullite are precipitated, and the liquidus viscosity is likely to decrease. ２ O ３ -SiO ２ In Al-based glasses, the glass is more likely to undergo phase separation. ２ O ３ The content is 5 to 15%, preferably 6 to 14%, more preferably 7 to 13%, and even more preferably 8 to 12%.

[0039] B ２ O ３ is a component that forms the glass skeleton and enhances meltability and devitrification resistance. ２ O ３ If the content of B is too high, the average thermal expansion coefficient tends to increase unduly. Also, the Young's modulus tends to decrease. Furthermore, the thermal stability tends to decrease, and the glass may be prone to phase separation. Therefore, B ２ O ３ The content is 5 to 20%, preferably 6 to 18%, 7 to 16%, 8 to 14%, particularly preferably 9 to 12%.

[0040] MgO is a component that reduces high-temperature viscosity and improves meltability, and among alkaline earth metal oxides, it is a component that significantly increases Young's modulus. However, if the MgO content is too high, devitrification resistance tends to decrease and the average thermal expansion coefficient tends to increase. Furthermore, thermal stability may decrease, and the glass may be prone to phase separation. Therefore, the MgO content is 1 to 10%, preferably 2 to 9%, 3 to 8%, and particularly preferably 4 to 7%.

[0041] CaO is a component that reduces high-temperature viscosity and significantly improves meltability without lowering the strain point. It also increases Young's modulus, improves thermal stability, and suppresses phase separation of glass. However, if the CaO content is too high, the average thermal expansion coefficient tends to increase unduly, and crystals such as anorthite precipitate, which tends to reduce the liquidus viscosity. Therefore, the CaO content is 0.1 to 3.9%, preferably 0.2 to 3.5%, 0.3 to 3%, 0.3 to 2.5%, 0.4 to 2%, and particularly preferably 0.5 to 1.5%.

[0042] SrO is a component that improves devitrification resistance and reduces high-temperature viscosity to improve meltability. It is also a component that improves thermal stability and suppresses phase separation of glass. However, if the SrO content is too high, the average thermal expansion coefficient tends to increase unduly, and the glass composition becomes unbalanced, which tends to reduce devitrification resistance. Therefore, the SrO content is 1 to 10%, preferably 1.2 to 8%, 1.4 to 6%, and particularly preferably 1.5 to 5%.

[0043] Molar ratio of Al ２ O ３ / B ２ O ３ is 0.5 to 1, preferably 0.55 to 1, 0.6 to 0.95, 0.65 to 0.95, and particularly preferably 0.7 to 0.9. ２ O ３ / B ２ O ３ If is smaller than the above range, the average thermal expansion coefficient at 20°C to 260°C will be 32 x 10 －７ / °C, the thermal stability is reduced, and phase separation of the glass is likely to occur. ２ O３ / B ２ O ３ If the value is larger than the above range, the thermal stability decreases, the phase separation of the glass tends to occur, and the devitrification resistance tends to decrease.

[0044] In addition to the above components, other components may be incorporated as optional components. From the viewpoint of accurately enjoying the effects of the present invention, the content of other components other than the above components is preferably 15% or less, 10% or less, and particularly preferably 5% or less in total.

[0045] BaO is a component that enhances devitrification resistance and improves the formability of glass. It also enhances thermal stability and suppresses phase separation of glass. However, if the BaO content is too high, the average thermal expansion coefficient tends to increase unduly. Therefore, the BaO content is preferably 0.1% or less.

[0046] Molar ratio (SiO ２ +Al ２ O ３ ) / (B ２ O ３ The molar ratio (SiO + MgO + CaO + SrO + BaO) is preferably 2.8 to 5, 3 to 4.5, and particularly preferably 3.2 to 4. ２ +Al ２ O ３ ) / (B ２ O ３ + MgO + CaO + SrO + BaO) is smaller than the above range, the average thermal expansion coefficient between 20°C and 260°C is 32 × 10 －７ On the other hand, the molar ratio (SiO ２ +Al ２ O ３ ) / (B ２ O ３ If the total content of the components (CaO, MgO, CaO, SrO, BaO) exceeds the above range, phase separation of the glass is likely to occur and the devitrification resistance is likely to decrease.

[0047] Molar ratio (SiO ２ +Al ２ O ３ ) / (MgO+CaO+SrO+BaO) is preferably 6 to 10, 6.5 to 9.5, particularly preferably 7 to 9. The molar ratio (SiO ２ +Al ２O ３ ) / (MgO+CaO+SrO+BaO) is smaller than the above range, the average thermal expansion coefficient between 20°C and 260°C is 32 × 10 －７ On the other hand, the molar ratio (SiO ２ +Al ２ O ３ If the ratio (MgO+CaO+SrO+BaO) / (MgO+CaO+SrO+BaO) exceeds the above range, phase separation of the glass is likely to occur and the devitrification resistance is likely to decrease.

[0048] Alkali metal oxide (Li ２ O, Na ２ O and K ２ However, if the content of alkali metal oxides is too high, the average thermal expansion coefficient increases significantly, and the average thermal expansion coefficient between 20°C and 260°C is 32×10 －７ / °C or more. In addition, alkali metal oxides are components that unduly lower the electrical resistance of the molten glass during glass melting, resulting in the generation of bubbles in the molten glass. As a result, the glass that is melted and formed is likely to contain residual bubbles, which not only may reduce the production efficiency of the glass substrate, but also may reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. Therefore, the content of alkali metal oxides (Li ２ O, Na ２ O and K ２ The total amount of O is preferably 0.1% or less.

[0049] Li ２ O is a component that improves melting property. ２ If the O content is too high, the thermal expansion coefficient tends to increase significantly. ２ O is a component that unduly lowers the electrical resistance of the molten glass during glass melting, resulting in the generation of bubbles in the molten glass. This makes the glass that is melted and formed more likely to contain residual bubbles, which not only may reduce the production efficiency of the glass substrate, but also may reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. Therefore, Li ２ The O content is preferably 0.1% or less.

[0050] Na ２O is a component that improves melting property. ２ If the O content is too high, the thermal expansion coefficient tends to increase significantly. ２ O is a component that unduly lowers the electrical resistance of the molten glass during glass melting, resulting in the generation of bubbles in the molten glass. This makes the glass that is melted and formed more likely to contain residual bubbles, which not only may reduce the production efficiency of glass substrates but also may reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. Therefore, Na ２ The O content is preferably 0.1% or less.

[0051] K ２ O is a component that improves melting property. ２ If the O content is too high, the thermal expansion coefficient tends to increase significantly. ２ O is a component that unduly lowers the electrical resistance of the molten glass during glass melting, resulting in the generation of bubbles in the molten glass. This makes the glass that is melted and formed more likely to contain residual bubbles, which not only may reduce the production efficiency of glass substrates but also may reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. Therefore, K ２ The O content is preferably 0.1% or less.

[0052] ZrO ２ is a component that increases weather resistance and Young's modulus. ２ If the content of ZrO is too high, the glass is prone to devitrification. ２ Since the raw materials introduced in are generally difficult to dissolve, there is a risk that undissolved crystalline foreign matter may be mixed into the glass. ２ The content is preferably 0 to 10%, 0 to 7%, 0 to 5%, 0 to 3%, 0 to 1%, particularly preferably 0 to 0.1%.

[0053] ZnO is a component that reduces high-temperature viscosity and significantly improves meltability and formability, and also improves weather resistance. However, if the ZnO content is too high, thermal stability decreases and phase separation of the glass becomes more likely to occur. Therefore, the ZnO content is preferably 0 to 3%, 0 to 2%, 0 to 1%, and particularly preferably 0 to 0.1%.

[0054] P ２ O ５ is a component that forms the skeleton of glass and is a component that can suppress the precipitation of devitrification crystals. ２ O ５ If the content of P is too high, the weather resistance of the glass decreases, and the thermal stability decreases, making the glass more susceptible to phase separation. ２ O ５ The content is preferably 0 to 15%, 0 to 10%, 0 to 5%, 0 to 2.5%, 0 to 1.5%, 0 to 0.5%, particularly preferably 0 to 0.3%.

[0055] SnO ２ is a component that has a good fining effect in the high temperature range and also reduces high-temperature viscosity. ２ If the content is too high, SnO ２ Therefore, devitrification crystals of SnO are likely to precipitate, and the ultraviolet transmittance may decrease. ２ The content is preferably 0 to 2%, 0.001 to 1%, 0.01 to 0.9%, particularly preferably 0.05 to 0.7%.

[0056] Fe ２ O ３ is a component that can be introduced as an impurity component or a fining component. ２ O ３ If the content of Fe is too high, the ultraviolet transmittance decreases, making it difficult to apply to ultraviolet LED packages, etc. ２ O ３ The content of is preferably 0 to 0.05%, 0 to 0.03%, 0 to 0.02%, particularly preferably 0.0001 to 0.01%. ２ O ３ " includes divalent iron oxide and trivalent iron oxide, and divalent iron oxide is Fe ２ O ３ Other oxides will be treated in the same manner, with the above oxides as the standard.

[0057] As a fining agent, As ２ O ３ , Sb ２ O ３However, from an environmental point of view, it is preferable to reduce these components as much as possible. ２ O ３ , Sb ２ O ３ The content of each of these elements is preferably 1% or less, 0.5% or less, 0.1% or less, particularly preferably 0.05% or less.

[0058] SO ３ is a component that has a clarifying effect. ３ If the content is too high, SO ２ Reboiling is likely to occur. ３ The content is preferably 0 to 1%, 0 to 0.5%, 0 to 0.1%, particularly preferably 0 to 0.01%.

[0059] Furthermore, as long as the glass properties are not impaired, metal powders such as F, C, Al, and Si may be incorporated as fining agents up to about 1% each. ２ etc. may be incorporated up to about 1%, but care must be taken to avoid a decrease in ultraviolet transmittance.

[0060] Cl is a component that promotes glass melting. Introducing Cl into the glass composition can lower the melting temperature and promote fining, which in turn makes it easier to reduce melting costs and extend the life of glass-making furnaces. However, if the Cl content is too high, there is a risk of corrosion of metal parts around the glass-making furnace. Therefore, the Cl content is preferably 3% or less, 1% or less, 0.5% or less, and particularly 0.1% or less.

[0061] TiO ２ is a component that reduces high-temperature viscosity and increases melting property, and also suppresses solarization. ２ If a large amount of TiO is introduced, the glass becomes colored and the transmittance tends to decrease. ２ The content is preferably 0 to 5%, 0 to 3%, 0 to 1%, particularly preferably 0 to 0.02%.

[0062] Y ２ O ３ , Nb ２ O ５ , La ２ O３ have the effect of increasing the strain point, Young's modulus, etc. However, if the content of each of these components exceeds 1%, particularly 5%, there is a risk that raw material costs and product costs will rise.

[0063] MoO ３ is a component that can be introduced as an impurity or a phase separation suppressing component. Mo is a component that can be contained in the electrode in the melting process, and MoO ３ is dissolved and incorporated into the molten glass. ３ When a large amount of MoO is introduced, the transmittance tends to decrease. ３ The content of is preferably 0 to 0.01%, 0 to 0.007%, 0 to 0.006%, particularly preferably 0 to 0.002%.

[0064] WO ３ is a component that can be introduced as an impurity or a phase separation suppressing component. ３ is a component that can be contained in the electrode in the melting process, and WO ３ However, WO ３ When a large amount of WO is introduced, the transmittance is likely to decrease. ３ The content of is preferably 0 to 0.01%, 0 to 0.007%, 0 to 0.006%, particularly preferably 0 to 0.002%.

[0065] The glass substrate of the present invention preferably has the following glass properties.

[0066] The average thermal expansion coefficient in the temperature range of 20°C to 260°C is 32 x 10 －７ / ℃, less than 30 × 10 －７ / ℃ or less, 30 x 10 －７ / °C or less, particularly 28.5 × 10 －７ / °C or less. If the average thermal expansion coefficient in the temperature range of 20°C to 260°C is outside the above range, it becomes difficult to match the thermal expansion coefficient with that of the silicon substrate, and dimensional changes (particularly warpage) of the glass substrate tend to occur. Note that the lower limit of the average thermal expansion coefficient in the temperature range of 20°C to 260°C is not particularly limited, but may be, for example, 20 x 10 －７ / °C or higher.

[0067] The glass substrate of the present invention is preferably not made of crystallized glass in which crystals are precipitated from the glass. If crystals are precipitated from the glass, there may be localized areas with high or low mechanical strength, resulting in a decrease in the mechanical strength of the glass. In addition, the precipitated crystals may scatter transmitted light, resulting in a decrease in the transmittance described below.

[0068] The higher the electrical resistivity of the molten glass, the better. ３．０ The electrical resistivity Logρ in dPa·s is preferably 0.5 Ω·cm or more, 0.6 Ω·cm or more, and particularly preferably 0.7 Ω·cm or more. ３．０ If the electrical resistivity Logρ in dPa·s does not satisfy the above range, the electrical resistance of the molten glass during melting becomes unduly low, and bubbles are likely to be generated in the molten glass. As a result, the glass to be melted and formed is likely to contain residual bubbles, which may not only reduce the production efficiency of the glass substrate, but also reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. ３．０ The upper limit of the electrical resistivity Logρ in dPa·s is not particularly limited, but is, for example, 4 Ω·cm or less.

[0069] Viscosity 10 at a measurement frequency of 1 kHz ５．０ The electrical resistivity Logρ in dPa·s is preferably 1.1 Ω·cm or more, 1.2 Ω·cm or more, particularly preferably 1.3 Ω·cm or more. ５．０ If the electrical resistivity Logρ in dPa·s does not satisfy the above range, the electrical resistance of the molten glass during melting becomes unduly low, and bubbles are likely to be generated in the molten glass. As a result, the glass to be melted and formed is likely to contain residual bubbles, which may not only reduce the production efficiency of the glass substrate, but also reduce the mechanical strength, weather resistance, and transmittance of the glass substrate. ５．０ The upper limit of the electrical resistivity Logρ in dPa·s is not particularly limited, but is, for example, 5 Ω·cm or less.

[0070] The Young's modulus is preferably 65 GPa or more, 67 GPa or more, particularly 70 GPa or more. If the Young's modulus is too low, the rigidity of the resulting laminate is likely to decrease after attaching the Si chip to the glass substrate. Furthermore, when an adhesive is spin-coated onto the glass substrate, the glass substrate is likely to be displaced. The upper limit of the Young's modulus is not particularly limited, but is, for example, 100 GPa or less, particularly 99 GPa or less.

[0071] The liquidus viscosity is 10 ３．５ dPa·s or more, 10 ４．６ dPa·s or more, 10 ４．７ dPa·s or more, especially 10 ５．０ In this way, devitrification crystals are less likely to precipitate during forming, making it easier to form a glass substrate by the down-draw method, particularly the overflow down-draw method. The upper limit of the liquidus viscosity is not particularly limited, but it is preferably 10 8．０ It may be dPa·s or less.

[0072] High temperature viscosity 10 ２．５ The temperature at viscosity dPa·s is preferably 1650°C or less, less than 1650°C, 1640°C or less, 1630°C or less, particularly preferably 1625°C or less. ２．５ When the temperature at high viscosity dPa·s is high, the melting property is reduced, and the manufacturing cost of the glass substrate rises. More specifically, undissolved crystalline foreign matter is likely to precipitate from the glass melt during melting, and the mechanical strength and transmittance of the obtained supporting glass substrate may be reduced, making it unsuitable for use as a glass substrate. ２．５ The lower limit of the temperature at dPa·s is not particularly limited, but may be, for example, 1000° C. or higher, particularly 1050° C. or higher.

[0073] The transmittance at 254 nm, calculated as a thickness of 1 mm, is preferably 5% or more, 10% or more, 20% or more, 25% or more, and particularly preferably 30% or more. If the transmittance at 254 nm, calculated as a thickness of 1 mm, is too low, it becomes difficult to apply the glass to cover glasses of ultraviolet LED packages or support glass substrates used to support processed substrates of semiconductor packages. The upper limit of the transmittance at 254 nm, calculated as a thickness of 1 mm, is not particularly limited, but may be, for example, 99.9% or less, 99% or less, 98% or less, and particularly 95% or less.

[0074] The transmittance at 350 nm, calculated as a thickness of 1 mm, is preferably 70% or more, 75% or more, 80% or more, and particularly preferably 85% or more. If the transmittance at 350 nm, calculated as a thickness of 1 mm, is too low, it becomes difficult to apply the glass to cover glasses of ultraviolet LED packages or support glass substrates used to support processed substrates of semiconductor packages. The upper limit of the transmittance at 350 nm, calculated as a thickness of 1 mm, is not particularly limited, but may be, for example, 99.9% or less, 99% or less, particularly 98% or less.

[0075] The transmittance at 500 nm, calculated as a thickness of 1 mm, is preferably 80% or more, 85% or more, 88% or more, and particularly preferably 90% or more. If the transmittance at 500 nm, calculated as a thickness of 1 mm, is too low, it becomes difficult to apply the glass to cover glasses of ultraviolet LED packages or support glass substrates used to support processed substrates of semiconductor packages. The upper limit of the transmittance at 500 nm, calculated as a thickness of 1 mm, is not particularly limited, but may be, for example, 99.9% or less, 99% or less, particularly 98% or less.

[0076] The strain point is preferably 590°C or higher, 610°C or higher, particularly preferably 630°C or higher. If the strain point is too low, unintended deformation of the glass is likely to occur when a functional film is formed on the glass surface at high temperatures. The upper limit of the strain point is not particularly limited, but may be, for example, 800°C or lower, particularly preferably 750°C or lower.

[0077] Annealing point (when the viscosity of the glass is about 10 １３The viscosity (temperature corresponding to dPa s) is preferably 600°C or higher, 630°C or higher, particularly 650°C or higher. If the annealing point is too low, the glass will be more likely to crack when formed. If the annealing point is too low, the glass will be more likely to shrink over time, which will lead to adverse effects such as poor dimensional accuracy. The upper limit of the annealing point is not particularly limited, but may be 850°C or lower, particularly 800°C or lower.

[0078] The glass substrate of the present invention can be used as a supporting glass substrate for supporting a processed substrate in a semiconductor package. For example, it preferably has a wafer shape with a diameter of 100 to 500 mm, a thickness of less than 2.0 mm, a total thickness variation (TTV) of 5 μm or less, and a warpage of 60 μm or less. Preferred shapes are described below.

[0079] The supporting glass substrate is preferably in the form of a wafer, with a diameter of 100 to 500 mm, particularly 150 to 450 mm. This facilitates application to the manufacturing process of fan-out type WLP and CoWoS. It also facilitates application to back-grinding of silicon substrates.

[0080] The supporting glass substrate may be rectangular, which makes it easier to apply to the manufacturing process of fan-out type PLP or CoWoS.

[0081] The plate thickness is preferably less than 2.0 mm, 1.5 mm or less, 1.2 mm or less, 1.1 mm or less, 1 mm or less, particularly preferably 0.9 mm or less. The thinner the plate thickness, the lighter the mass of the laminate, thereby improving handleability. On the other hand, if the plate thickness is too thin, the strength of the supporting glass substrate itself decreases, making it difficult to function as a supporting substrate. Therefore, the plate thickness is preferably 0.1 mm or more, 0.2 mm or more, 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, 0.6 mm or more, particularly preferably more than 0.7 mm.

[0082] The total thickness variation (TTV) is preferably 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, less than 2 μm, 1.5 μm or less, 1 μm or less, particularly 0.1 to less than 1 μm. The arithmetic mean roughness Ra is preferably 20 nm or less, 10 nm or less, 5 nm or less, 2 nm or less, 1 nm or less, particularly 0.5 nm or less. The lower limit of the arithmetic mean roughness Ra is not particularly limited, but may be, for example, 0.1 nm or more. The higher the surface precision, the easier it is to improve the processing precision. In particular, the wiring precision can be improved, enabling high-density wiring. Furthermore, the strength of the supporting glass substrate is improved, making the supporting glass substrate and the laminate less susceptible to breakage. Furthermore, the number of times the supporting glass substrate can be reused can be increased. The "arithmetic mean roughness Ra" can be measured using a stylus surface roughness meter or an atomic force microscope (AFM).

[0083] The support glass substrate is preferably formed by the overflow downdraw method and then has its surface polished, which makes it easier to regulate the total thickness variation (TTV) to less than 2 μm, 1.5 μm or less, 1 μm or less, particularly 0.1 to less than 1 μm.

[0084] The amount of warpage is preferably 60 μm or less, 55 μm or less, 50 μm or less, 1 to 45 μm, and particularly preferably 5 to 40 μm. The smaller the amount of warpage, the easier it is to increase the precision of processing. In particular, since wiring precision can be increased, high-density wiring becomes possible.

[0085] In the case of a wafer shape, the circularity is preferably 1 mm or less, 0.1 mm or less, 0.05 mm or less, and particularly preferably 0.03 mm or less. The lower limit of the circularity is not particularly limited, but may be, for example, 0.001 mm or more. The smaller the circularity, the easier it is to apply to the manufacturing process of fan-out type WLP or CoWoS. Note that "circularity" is the value obtained by subtracting the minimum value from the maximum value of the outer shape of the wafer, excluding the notch portion.

[0086] The supporting glass substrate preferably has a notch portion (notch-shaped alignment portion), and the deep portion of the notch portion is more preferably substantially circular or V-groove-shaped in plan view. This makes it easier to fix the position of the supporting glass substrate by abutting a positioning member such as a positioning pin against the notch portion of the supporting glass substrate. As a result, alignment of the supporting glass substrate and the processing substrate becomes easier. In particular, forming a notch portion in the processing substrate and abutting a positioning member thereon makes it easier to align the entire laminate.

[0087] The support glass substrate is preferably formed by a downdraw method, particularly an overflow downdraw method. The overflow downdraw method is a method for producing a glass substrate by overflowing molten glass from both sides of a heat-resistant trough-shaped structure, and drawing the overflowed molten glass downward while joining at the lower end of the trough-shaped structure. In the overflow downdraw method, the surface that will become the surface of the glass substrate does not contact the trough-shaped refractory and is formed in a free surface state. Therefore, by a small amount of polishing, the total thickness variation (TTV) can be reduced to less than 2 μm, particularly less than 1 μm. As a result, the manufacturing cost of the glass substrate can be reduced.

[0088] The supporting glass substrate of the present invention is preferably not subjected to ion exchange treatment and preferably does not have a compressive stress layer on its surface. Since ion exchange treatment increases the manufacturing cost of the supporting glass substrate, not performing the ion exchange treatment makes it possible to reduce the manufacturing cost of the supporting glass substrate. Furthermore, since ion exchange treatment makes it difficult to reduce the total thickness variation (TTV) of the supporting glass substrate, not performing the ion exchange treatment makes it easier to resolve such a problem. Note that the supporting glass substrate of the present invention does not exclude an embodiment in which an ion exchange treatment is performed to form a compressive stress layer on its surface. Focusing solely on the viewpoint of increasing mechanical strength, it is preferable to perform ion exchange treatment to form a compressive stress layer on its surface.

[0089] The laminate is a laminate including at least a processing substrate and a supporting glass substrate used to support the processing substrate, characterized in that the supporting glass substrate is the above-mentioned supporting glass substrate. Furthermore, it is preferable that the processing substrate includes at least a semiconductor chip molded with a sealing material. A glass substrate satisfying the above-mentioned configuration has a high Young's modulus, which makes it easy to maintain the rigidity of the laminate, and can suppress the occurrence of deformation, warping, breakage, etc. of the processing substrate. Therefore, the laminate of the present invention can suppress a decrease in the reliability of the processing of the processing substrate.

[0090] The laminate preferably has an adhesive layer between the processing substrate and the supporting glass substrate. The adhesive layer is preferably a resin, such as a thermosetting resin or a photocurable resin (particularly an ultraviolet-curable resin). This facilitates fixing the silicon substrate and the supporting glass substrate in the backgrinding process. The adhesive layer preferably has heat resistance that can withstand heat treatments in the manufacturing process of fan-out WLP or CoWoS. This makes the adhesive layer less likely to melt in the manufacturing process of fan-out WLP or CoWoS, thereby improving the accuracy of the processing process. Note that ultraviolet-curable tape can also be used as the adhesive layer to easily fix the processing substrate and the supporting glass substrate.

[0091] The laminate of the present invention preferably further has a release layer between the processing substrate and the supporting glass substrate, more specifically between the processing substrate and the adhesive layer, or between the supporting glass substrate and the adhesive layer. In this way, after performing a predetermined processing treatment on the processing substrate, the processing substrate can be easily peeled off from the supporting glass substrate. From the viewpoint of productivity, peeling of the processing substrate is preferably performed by irradiating light such as ultraviolet laser light.

[0092] The release layer is made of a material that undergoes "intralayer peeling" or "interfacial peeling" when irradiated with light such as laser light. In other words, when irradiated with light of a certain intensity, the interatomic or intermolecular bonding force between atoms or molecules disappears or decreases, causing ablation or the like, resulting in peeling. When irradiated with light, the components contained in the release layer may become gaseous and be released, leading to separation, or the release layer may absorb light, become gaseous, and release the vapor, leading to separation.

[0093] In the laminate, the supporting glass substrate is preferably larger than the processing substrate, so that even if the centers of the processing substrate and the supporting glass substrate are slightly separated when they are supported, the edge of the processing substrate is less likely to protrude from the supporting glass substrate.

[0094] The method for manufacturing a laminate includes the steps of preparing the support glass substrate, preparing a processing substrate, and laminating the support glass substrate and the processing substrate to obtain a laminate, thereby making it possible to manufacture a laminate that can suppress a decrease in reliability of processing of the processing substrate.

[0095] The method for manufacturing a semiconductor package is characterized by comprising the steps of preparing the laminate described above and processing the processing substrate. In other words, the method for manufacturing a semiconductor package of the present invention comprises the steps of preparing at least a processing substrate and a supporting glass substrate used to support the processing substrate, and processing the processing substrate, and is characterized in that the supporting glass substrate is the supporting glass substrate described above.

[0096] The method for manufacturing a semiconductor package preferably further includes a step of transporting the laminate. This increases the processing efficiency of the processing. Note that the "step of transporting the laminate" and the "step of performing processing on the processing substrate" do not need to be performed separately and may be performed simultaneously.

[0097] In the semiconductor package manufacturing method of the present invention, the processing is preferably a process of wiring one surface of the processed substrate or a process of forming solder bumps on one surface of the processed substrate. In the semiconductor package manufacturing method of the present invention, these steps can be carried out appropriately because the processed substrate is less likely to change in size during these processes.

[0098] In addition to the above, the processing may be any of the following: mechanical polishing of one surface of the processing substrate (usually the surface opposite the supporting glass substrate), dry etching of one surface of the processing substrate (usually the surface opposite the supporting glass substrate), and wet etching of one surface of the processing substrate (usually the surface opposite the supporting glass substrate). The semiconductor package manufacturing method of the present invention makes it difficult for the processing substrate to warp, and can maintain the rigidity of the laminate. As a result, the above processing can be performed appropriately.

[0099] The present invention will be described below based on examples. Note that the following examples are merely illustrative and the present invention is not limited to the following examples.

[0100] Tables 1 to 4 show examples of the present invention (samples Nos. 1 to 30) and a comparative example (sample No. 31).

[0101]

[0102]

[0103]

[0104]

[0105] First, a glass batch prepared by blending glass raw materials to obtain the glass composition shown in the table was placed in a platinum crucible and melted at 1400 to 1700°C for 3 to 24 hours. The glass batch was homogenized by stirring using a platinum stirrer. The molten glass was then poured onto a carbon plate, formed into a plate, and slowly cooled from a temperature about 20°C higher than the annealing point to 30°C at a rate of 3°C / min.

[0106] The density, average thermal expansion coefficient in the temperature range of 20 to 260°C, Young's modulus, transmittance at 500 nm when converted to a thickness of 1 mm, transmittance at 350 nm when converted to a thickness of 1 mm, transmittance at 254 nm when converted to a thickness of 1 mm, strain point, annealing point, high-temperature viscosity 10 ４．０ Temperature at dPa·s, high temperature viscosity 10 ３．０ Temperature at dPa·s, high temperature viscosity 10 ２．５ Temperature at dPa·s, high temperature viscosity 10 ２．０ The temperature at dPa·s, the liquidus temperature, the liquidus viscosity log η, and the presence or absence of phase separation of the glass were evaluated.

[0107] The density is a value measured by the well-known Archimedes method.

[0108] The average thermal expansion coefficient in the temperature range of 20 to 260° C. is a value measured with a dilatometer.

[0109] The Young's modulus is a value measured by a resonance method.

[0110] The transmittance at 500 nm, calculated as a value equivalent to a thickness of 1 mm, is a value including reflection loss measured using a double-beam spectrophotometer. The measurement samples used were optically polished (mirror-finished) on both sides. The surface roughness (Ra) of the glass surface of these measurement samples was measured using an AFM and found to be 0.5 to 1.0 nm in a measurement area of ​​5 μm × 5 μm.

[0111] The transmittance at 350 nm, calculated as a value equivalent to a thickness of 1 mm, is a value including reflection loss measured using a double-beam spectrophotometer. The measurement samples used were optically polished (mirror-finished) on both sides. The surface roughness Ra of the glass surfaces of these measurement samples was measured using an AFM and found to be 0.5 to 1.0 nm in a measurement area of ​​5 μm × 5 μm.

[0112] The transmittance at 254 nm, calculated as a value equivalent to a thickness of 1 mm, is a value including reflection loss measured using a double-beam spectrophotometer. The measurement samples used were optically polished (mirror-finished) on both sides. The surface roughness Ra of the glass surface of these measurement samples was measured using an AFM and was found to be 0.5 to 1.0 nm in a measurement area of ​​5 μm × 5 μm.

[0113] The strain point and annealing point are values ​​measured based on the method of ASTM C336.

[0114] High temperature viscosity 10 ４．０ dPa·s, 10 ３．０ dPa·s, 10 ２．５ dPa·s and 10 ２．０ The temperature at dPa·s is a value measured by the platinum sphere pull-up method.

[0115] The liquidus temperature is a value obtained by placing a glass powder that has passed through a standard sieve of 30 mesh (500 μm) and remains on a 50 mesh (300 μm) sieve in a platinum boat, holding the boat in a temperature gradient furnace for 24 hours, and then measuring the temperature at which crystals precipitate by microscopic observation. The liquidus viscosity log η is a value obtained by measuring the viscosity of the glass at the liquidus temperature by the platinum sphere pulling method.

[0116] The state of phase separation of the glass was judged by measuring the transmittance of visible light at 500 nm, converted into a thickness of 1 mm. If phase separation occurs, the glass becomes cloudy, and the transmittance of visible light at 500 nm decreases. Therefore, if the transmittance is 80% or more, it is determined that no phase separation has occurred and is rated as "Good," while if it is less than 80%, it is determined that phase separation has occurred and is rated as "Poor."

[0117] As is clear from the table, samples No. 1 to No. 30 have an average thermal expansion coefficient of 32 × 10 －７ / °C, no glass phase separation occurred and the thermal stability was high. On the other hand, sample No. 31 exhibited glass phase separation and had low thermal stability. From the above, it was determined that samples Nos. 1 to 30 were suitable as glass substrates, while sample No. 31 was unsuitable as a glass substrate.

[0118] In the above examples, the molten glass was poured out and formed into a flat plate shape. However, in the case of industrial-scale production, it is preferable to form the glass into a flat plate shape by an overflow downdraw method or the like and polish both surfaces of the glass.

[0119] The glass substrate of the present invention is suitable as a supporting glass substrate for use in a semiconductor package, and is also suitable as a glass substrate for use in, for example, ultraviolet light-emitting diodes (LEDs), light-receiving element encapsulation packages, ultraviolet light-emitting lamps, liquid crystal displays, organic EL displays, and information recording media.

Claims

The glass composition is, in mol%, SiO ２ 60-80%, Al ２ O ３ 5-15%, B ２ O ３ 5 to 20%, MgO 1 to 10%, CaO 0.1 to 3.9%, SrO 1 to 10%, and the molar ratio of Al ２ O ３ / B ２ O ３ is 0.5 to 1, and the average thermal expansion coefficient in the temperature range of 20°C to 260°C is 32 × 10 －７ / °C or less. 　 The glass composition is expressed as a molar ratio (SiO ２ +Al ２ O ３ ) / (B ２ O ３ 2. The glass substrate according to claim 1, wherein the total amount of SrO, BaO, and MgO is 2.8 to 5. 　 The glass composition is expressed as a molar ratio (SiO ２ +Al ２ O ３ 3. The glass substrate according to claim 1, wherein the ratio of MgO to CaO is 6 to 10. The average thermal expansion coefficient in the temperature range of 20°C to 260°C is 30 x 10 －７ The glass substrate according to claim 1 or 2, wherein the temperature is less than 100°C.

3. The glass substrate according to claim 1, wherein the glass composition contains an alkali metal oxide in an amount of 0.1% or less by mole.

3. The glass substrate according to claim 1, wherein the glass composition contains BaO in an amount of 0.1% or less by mole.

3. The glass substrate according to claim 1, which is not made of glass-ceramics.

3. The glass substrate according to claim 1, wherein the glass substrate has a Young's modulus of 65 GPa or more. 　 Liquidus viscosity is 10 ３．５ The glass substrate according to claim 1 or 2, having a viscosity of dPa·s or more. High temperature viscosity 10 ２．５ The glass substrate according to claim 1 or 2, wherein the temperature at dPa·s is less than 1650°C.

3. The glass substrate according to claim 1, wherein the glass substrate has a transmittance including reflection loss at 254 nm, converted into a value of 1 mm thickness, of 5% or more.

3. A supporting glass substrate according to claim 1, which is used to support a processed substrate.

13. The supporting glass substrate according to claim 12, having a wafer shape with a diameter of 100 to 500 mm, a thickness of less than 2.0 mm, a total thickness variation (TTV) of 5 μm or less, and a warpage of 60 μm or less.

13. The supporting glass substrate according to claim 12, having a substantially rectangular shape with at least one side of 300 mm or more, a thickness of less than 2.0 mm, a total thickness variation (TTV) of 5 μm or less, and a warpage of 60 μm or less. 　 The supporting glass substrate according to claim 12, which is a supporting glass substrate for supporting a processed substrate, and is used for supporting a fan-out type wafer level package or a fan-out type panel level package. 　 The supporting glass substrate according to claim 12, which is a supporting glass substrate for supporting a processed substrate and is used for supporting a semiconductor for back grinding. 　 A laminate comprising at least a processed substrate and a supporting glass substrate used to support the processed substrate, A laminate, wherein the supporting glass substrate is the supporting glass substrate according to claim 12.

20. The laminate of claim 17, wherein the engineered substrate comprises at least a semiconductor chip molded with an encapsulant. 　 providing a supporting glass substrate according to claim 12; providing a processing substrate; and laminating the supporting glass substrate and the processing substrate to obtain a laminate. 　 Providing a laminate according to claim 17; and performing a processing process on the processing substrate. 　 The method for manufacturing a semiconductor package according to claim 20 , wherein the processing step includes a step of wiring one surface of the processing substrate.

21. The method of manufacturing a semiconductor package according to claim 20, wherein the processing step includes forming solder bumps on one surface of the processing substrate.

Images