JP2022161964A - Method for manufacturing support glass substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for increasing Young's modulus of a support glass substrate without deteriorating moldability.

SOLUTION: A method for manufacturing a support glass substrate for supporting a processed substrate includes: a molding step of molding a support glass substrate; and a heat treatment step where the molded support glass substrate is subject to heat treatment to increase Young's modulus of the support glass substrate.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2023,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a supporting glass substrate for supporting a processed substrate, and more specifically, to a method for supporting a processed substrate having at least a semiconductor chip molded with a sealing material in a semiconductor package manufacturing process. The present invention relates to a method for manufacturing a supporting glass substrate.

Portable electronic devices such as mobile phones, notebook personal computers, and PDAs (Personal Data Assistance) are required to be smaller and lighter. Along with this, the mounting space for the semiconductor chips used in these electronic devices is severely restricted, and high-density mounting of the semiconductor chips has become an issue. Therefore, in recent years, high-density mounting of semiconductor packages has been attempted by a three-dimensional mounting technique, that is, by stacking semiconductor chips and connecting wires between the semiconductor chips.

Further, a conventional wafer level package (WLP) is manufactured by forming bumps in a wafer state and then separating them into individual pieces by dicing. However, the conventional WLP has the problem that it is difficult to increase the number of pins and that the semiconductor chip is likely to be chipped or the like because the semiconductor chip is mounted with the back surface thereof exposed.

Therefore, as a new WLP, a fan-out type WLP has been proposed. The fan-out type WLP can increase the number of pins, and can prevent chipping of the semiconductor chip by protecting the end of the semiconductor chip.

The fan-out type WLP has a manufacturing method of a chip-first type and a chip-last type. In the chip-first type, for example, after forming a processed substrate by molding a plurality of semiconductor chips with a resin sealing material, there is a step of wiring on one surface of the processed substrate, a step of forming solder bumps, and the like. In the chip-last type, for example, after a wiring layer is placed on a support substrate, a plurality of semiconductor chips are arranged and molded with a resin sealing material to form a processed substrate, and then solder bumps are formed. have

Furthermore, recently, a semiconductor package called a panel level package (PLP) has also been considered. In PLP, a rectangular support substrate is used instead of a wafer shape in order to increase the number of semiconductor packages that can be obtained per support substrate and reduce the manufacturing cost.

Since the manufacturing process of these semiconductor packages involves heat treatment at about 200° C., there is a risk that the encapsulant will be deformed and the processed substrate will be warped. If the processed substrate is warped, it becomes difficult to form high-density wiring on one surface of the processed substrate, and it becomes difficult to form solder bumps accurately.

Under these circumstances, use of a glass substrate to support the processed substrate has been studied in order to suppress warpage of the processed substrate (see Patent Document 1).

A glass substrate has a smooth surface and is rigid. Therefore, if a glass substrate is used as the support substrate, it is possible to firmly and accurately support the substrate to be processed. A glass substrate easily transmits light such as ultraviolet light and infrared light. Therefore, if a glass substrate is used as the support substrate, the substrate to be processed can be easily fixed by providing an adhesive layer such as an ultraviolet curable adhesive. Further, by providing a peeling layer or the like that absorbs infrared rays, the substrate to be processed can be easily separated. As another method, the substrate to be processed can be easily fixed and separated by providing an adhesive layer or the like with an ultraviolet curable tape or the like.

JP 2015-78113 A

"Bimetal and Thermostat" [Searched June 9, 2017] Internet <URL: http://ktc-bimetal.co.jp/pdf/bimetal.pdf>

In the manufacturing process of fan-out type WLP and PLP, increasing the Young's modulus of the glass substrate is considered as a method of reducing the warp of the laminated substrate. For example, in Non-Patent Document 1, when different materials having different coefficients of thermal expansion are bonded together to produce a laminated substrate, if the Young's modulus of one material is relatively high with respect to the other material, the It is described that warpage can be reduced. Therefore, it is considered that increasing the Young's modulus of the supporting glass substrate can reduce the warpage of the laminated substrate including the processed substrate and the supporting glass substrate.

However, if an attempt is made to increase the Young's modulus of the support glass substrate by changing the glass composition, the structure of the glass becomes unstable, making it difficult to form a plate, and the production efficiency of the support glass substrate tends to decrease.

The present invention has been made in view of the above circumstances, and a technical object thereof is to devise a method for increasing the Young's modulus of a supporting glass substrate without deteriorating moldability.

As a result of repeating various experiments, the present inventor found that the above technical problems can be solved by heat-treating the support glass substrate after molding, and proposes the present invention. That is, the method for manufacturing a supporting glass substrate of the present invention is a method for manufacturing a supporting glass substrate for supporting a processed substrate, which includes a molding step of molding the supporting glass substrate, and heat-treating the supporting glass substrate after molding to support the supporting glass substrate. and a heat treatment step for increasing the Young's modulus of the glass substrate. Here, "Young's modulus" refers to a value measured by a bending resonance method.

The method for manufacturing a supporting glass substrate of the present invention preferably includes a heat treatment step of heat-treating the supporting glass substrate after molding to increase the Young's modulus of the supporting glass substrate. By doing so, the Young's modulus of the supporting glass substrate can be increased without deteriorating the moldability. As a result, it becomes easier to reduce the warpage of the laminated substrate in the manufacturing process of the fan-out type WLP and PLP.

In addition, in the method for manufacturing a supporting glass substrate of the present invention, it is preferable to heat-treat the supporting glass substrate after molding so that the Young's modulus of the supporting glass substrate falls within the control target range.

In the method for manufacturing a supporting glass substrate of the present invention, the maximum temperature of the heat treatment is preferably higher than (the strain point of the supporting glass substrate -100)°C.

In the method for manufacturing a supporting glass substrate of the present invention, the heat treatment temperature is preferably lowered at a rate of 5° C./min or less after reaching the maximum heat treatment temperature.

Further, in the method for manufacturing a supporting glass substrate of the present invention, it is preferable to reduce the amount of warping of the supporting glass substrate to 40 μm or less by heat treatment. Here, the "warp amount" 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 lowest point and the least-squares focal plane in the entire supporting glass substrate. , for example, can be measured by SBW-331ML/d manufactured by Kobelco Research Institute.

Further, in the method for manufacturing a supporting glass substrate of the present invention, a heat treatment setter having a dimension larger than that of the supporting glass substrate is prepared, and after placing the formed supporting glass substrate on the heat treatment setter, a heat treatment step is performed. preferably provided.

Further, in the method for manufacturing a supporting glass substrate of the present invention, the supporting glass substrate is preferably molded so as to have a plate thickness of 400 μm or more and less than 2 mm.

Further, in the method for manufacturing a supporting glass substrate of the present invention, the supporting glass substrate is preferably formed by an overflow down-draw method.

Moreover, the method for manufacturing a supporting glass substrate of the present invention preferably includes a polishing step of polishing the surface of the supporting glass substrate to reduce the total thickness deviation (TTV) to less than 2.0 μm after the heat treatment step. Here, the "total thickness deviation (TTV)" is the difference between the maximum thickness and the minimum thickness of the entire support glass substrate, and can be measured by SBW-331ML/d manufactured by Kobelco Research Institute, Inc., for example.

Moreover, it is preferable that the manufacturing method of the supporting glass substrate of the present invention comprises a cutting and removing step of cutting and removing the peripheral portion of the supporting glass substrate after the heat treatment step.

A method for manufacturing a semiconductor package according to the present invention includes a lamination step of fabricating a laminated substrate including at least a processed substrate and a supporting glass substrate for supporting the processed substrate, and processing of processing the processed substrate of the laminated substrate. It is preferable that the supporting glass substrate is produced by the above-described method for manufacturing a supporting glass substrate.

Further, in the method of manufacturing a semiconductor package of the present invention, it is preferable that the processed substrate includes at least a semiconductor chip molded with a sealing material.

In the method of manufacturing a semiconductor package of the present invention, the processing preferably includes wiring on one surface of the processed substrate.

Further, in the method of manufacturing a semiconductor package of the present invention, the processing preferably includes processing for forming solder bumps on one surface of the processed substrate.

1 is a conceptual perspective view showing an example of a laminated substrate according to the present invention; FIG. FIG. 10 is a conceptual cross-sectional view showing a chip-first type manufacturing process of a fan-out type WLP;

The method for manufacturing the supporting glass substrate of the present invention will be described in detail below.

In the method for producing a supporting glass substrate of the present invention, first, glass raw materials are prepared and mixed to produce a glass batch, and after the glass batch is put into a glass melting furnace, the resulting molten glass is clarified and stirred. Then, it is preferable to supply the support glass substrate to a forming apparatus and form it into a plate shape.

In the method for producing a supporting glass substrate of the present invention, it is preferable to prepare a glass batch so that the supporting glass substrate has a Young's modulus of 60 GPa or higher (preferably 65 GPa or higher, 70 GPa or higher, particularly 75 to 130 GPa). If the ratio of the semiconductor chip in the processed substrate is small and the ratio of the sealing material is large, the rigidity of the entire laminated substrate decreases, and the processed substrate tends to warp during the processing step. Therefore, if the Young's modulus of the supporting glass substrate is increased, the warp of the processed substrate can be easily reduced, and the processed substrate can be firmly and accurately supported.

The glass batch is preferably prepared to have a desired coefficient of thermal expansion. Specifically, when the ratio of the semiconductor chip in the processed substrate is small and the ratio of the sealing material is large, the glass batch is prepared so as to obtain a high-expansion glass. If the proportion is large and the proportion of sealing material is small, it is preferable to prepare the glass batch so as to obtain a low-expansion glass.

When the average linear thermal expansion coefficient in the temperature range of 30 to 380 ° C. is regulated to 0 × 10 ^-7 / ° C. or more and less than 50 × 10 ^-7 / ° C., the glass composition of the supporting glass substrate is, in mass%, SiO ₂ 55-75%, Al ₂ O ₃ 15-30%, Li ₂ O 0.1-6%, Na ₂ O + K ₂ O (total amount of Na ₂ O and K ₂ O) 0-8%, MgO + CaO + SrO + BaO (MgO , CaO, SrO and BaO) 0-10%, SiO ₂ 55-75%, Al ₂ O ₃ 10-30%, Li ₂ O+Na ₂ O+K ₂ It is also preferred to prepare the glass batch to contain O (sum of Li ₂ O, Na ₂ O and K ₂ O) 0-0.3%, MgO + CaO + SrO + BaO 5-20%, SiO ₂ 55-68%, It is also preferred to prepare the glass batch to contain 12-25% Al ₂ O ₃ , 0-15% B ₂ O ₃ , 5-30% MgO+CaO+SrO+BaO. When the average linear thermal expansion coefficient in the temperature range of 30 to 380 ° C. is regulated to 50 × 10 ^-7 / ° C. or more and less than 70 × 10 ^-7 / ° C., the glass composition of the supporting glass substrate is, in mass%, SiO ₂ 55-75%, Al ₂ O _3-15 %, B ₂ O _5-20 %, MgO 0-5%, CaO 0-10%, SrO 0-5%, BaO 0-5%, ZnO 0 5% Na ₂ O, 5-15% Na 2 O, 0-10% K ₂ O, preferably 64-71% SiO ₂ , 5-10% Al ₂ O _, B _{2O3 8-15} %, MgO 0-5%, CaO 0-6%, SrO 0-3%, BaO 0-3%, ZnO 0-3%, _Na2O 5-15%, _K2O0 It is even more preferred to prepare the glass batch to contain ~5%. When the average linear thermal expansion coefficient in the temperature range of 30 to 380 ° C. is regulated to 70 × 10 ^-7 / ° C. or more and 85 × 10 ^-7 / ° C. or less, the glass composition of the supporting glass substrate is, in mass%, SiO ₂ 60-75%, _{Al2O3 5-15} % _, B2O3 _5-20 %, MgO 0-5%, CaO 0-10%, SrO 0-5%, BaO 0-5%, ZnO 0 5% Na ₂ O 7-16% K ₂ O 0-8%, preferably 60-68% SiO ₂ , 5-15% Al ₂ O ₃ , B _{2O3 5-20} %, MgO 0-5%, CaO 0-10%, SrO 0-3%, BaO 0-3%, ZnO 0-3%, _Na2O 8-16%, _K2O0 More preferably, the glass batch is prepared to contain ~3%. When the average linear thermal expansion coefficient in the temperature range of 30 to 380 ° C. is restricted to more than 85 × 10 ^-7 / ° C. and 120 × 10 ^-7 / ° C. or less, the glass composition of the supporting glass substrate is, in mass%, SiO ₂ 55-70%, Al ₂ O _3-13 %, B ₂ O _2-8 %, MgO 0-5%, CaO 0-10%, SrO 0-5%, BaO 0-5%, ZnO 0 It is preferred to prepare the glass batch to contain ~5%, Na ₂ O 10-21%, K ₂ O 0-5%. When the average linear thermal expansion coefficient in the temperature range of 30 to 380 ° C. is restricted to more than 120 × 10 ^-7 / ° C. and 165 × 10 ^-7 / ° C. or less, the glass composition of the supporting glass substrate is, in mass%, SiO _{2 53-65} %, _{Al2O3 3-13} % _, B2O3 0-5%, MgO 0.1-6%, CaO 0-10%, SrO 0-5%, BaO 0-5%, Preferably, the glass batch is prepared to contain 0-5% ZnO, 20-40% Na ₂ O+K ₂ O, 12-21% Na ₂ O, 7-21% K ₂ O. By doing so, it becomes easier to adjust the thermal expansion coefficient within the control target range, and the resistance to devitrification is improved, so that it becomes easier to form a support glass substrate having a small total thickness deviation (TTV). The “average linear thermal expansion coefficient in the temperature range of 30 to 380° C.” refers to the value measured with a dilatometer.

_one selected from the group of _{As2O3 ,} Sb2O3 _{, CeO2} , SnO2, F, Cl _, SO3 ₍ preferably the group of SnO2 _, Cl, SO3) as a fining agent in the glass _batch Alternatively, two or more of them may be added in an amount of 0.05 to 2% by mass. The total amount of SnO ₂ , SO ₃ and Cl is preferably 0-1% by weight, 100-3000 ppm (0.01-0.3% by weight), 300-2500 ppm, especially 500-2500 ppm. In addition, if the total amount of SnO ₂ , SO ₃ and Cl is less than 100 ppm, it becomes difficult to enjoy the refining effect.

From an environmental point of view, it is preferable to refrain from using As ₂ O ₃ , Sb ₂ O ₃ and F as much as possible, and it is preferable not to contain them substantially. Here, "substantially free of" specifically means that the content of the specified component is less than 500 ppm (0.05% by mass). From an environmental point of view, it is also preferred that the glass composition contains substantially no PbO or Bi ₂ O ₃ .

The liquidus temperature of the supporting glass substrate is less than 1150°C (preferably 1120°C or less, 1100°C or less, 1080°C or less, 1050°C or less, 1010°C or less, 980°C or less, 960°C or less, 950°C or less, particularly 940°C or less ) is preferred to prepare the glass batch. The liquidus viscosity of the supporting glass substrate is 10 ^4.8 dPa·s or more (preferably 10 ^5.0 dPa·s or more, 10 ^5.2 dPa·s or more, 10 ^5.4 dPa·s or more, particularly 10 ^{5 .6} dPa·s or more) is preferably prepared in the glass batch. This makes it easier to form by the down-draw method, especially the overflow down-draw method, so that the total plate thickness deviation (TTV) can be reduced without polishing the surface. Alternatively, a small amount of polishing can reduce the total thickness variation (TTV) to less than 2.0 μm, especially less than 1.0 μm. As a result, the manufacturing cost of the supporting glass substrate can also be reduced. In addition, the "liquidus temperature" is measured by placing the glass powder that passes through a 30 mesh (500 µm) standard sieve and remains on the 50 mesh (300 µm) in a platinum boat and then holding it in a temperature gradient furnace for 24 hours to obtain crystals. It can be calculated by measuring the temperature at which precipitation occurs. The "liquidus viscosity" can be calculated by measuring the viscosity of the glass at the liquidus temperature by the platinum ball pull-up method.

In the manufacturing method of the supporting glass substrate of the present invention, it is preferable to form the supporting glass substrate so as to have a plate thickness of 400 μm or more and less than 2 mm. The thickness of the supporting glass substrate is preferably 400 μm or more, 500 μm or more, 600 μm or more, 700 μm or more, 800 μm or more, 900 μm or more, and particularly 1000 μm or more. If the thickness of the supporting glass substrate is too small, the laminated substrate is likely to warp, and the mechanical strength of the laminated substrate is lowered, so that the supporting glass substrate is likely to be damaged during the manufacturing process of the semiconductor package. On the other hand, if the thickness of the supporting glass substrate is too large, the mass of the laminated substrate increases, resulting in poor handleability. In addition, in the semiconductor package manufacturing process, there is a possibility that the laminated substrate cannot clear the height limit within the semiconductor package manufacturing apparatus. Therefore, the thickness of the support glass substrate is preferably less than 2.0 mm, 1.5 mm or less, 1.2 mm or less, and particularly 1.1 mm or less.

It is preferable to form the support glass substrate by a down-draw method, particularly an overflow down-draw method. In the overflow down-draw method, molten glass is allowed to overflow from both sides of a heat-resistant trough-shaped structure, and the overflowing molten glass is merged at the lower top end of the trough-shaped structure to form a confluence surface in the central region in the plate thickness direction. It is a method of stretching downward while forming. In the overflow down-draw method, the surface to be the glass surface does not contact the gutter-shaped refractory and is formed in a free surface state, so the total thickness deviation (TTV) is reduced without polishing the surface. be able to. Alternatively, a small amount of polishing can reduce the total thickness variation (TTV) to less than 2.0 μm, especially less than 1.0 μm. As a result, the manufacturing cost of the supporting glass substrate can be reduced.

Other than the overflow down-draw method, for example, a slot-down method, a redraw method, a float method, and the like can also be adopted as a method for forming the supporting glass substrate.

The method for manufacturing a supporting glass substrate of the present invention preferably includes a step of measuring the Young's modulus of the supporting glass substrate after molding before the heat treatment step. By doing so, it becomes easier to optimize the heat treatment conditions (maximum heat treatment temperature, heat treatment temperature drop rate, etc.) and control the Young's modulus of the supporting glass substrate within the target control range.

In the method for manufacturing a supporting glass substrate of the present invention, a step of washing the supporting glass substrate may be provided before the heat treatment step. As a result, even if foreign matter adheres to the supporting glass substrate, it is possible to prevent the adhering foreign matter from sticking to the surface of the supporting glass substrate due to the heat treatment.

A method for manufacturing a supporting glass substrate of the present invention includes a heat treatment step of heat-treating a molded supporting glass substrate to increase the Young's modulus of the supporting glass substrate. In the heat treatment step, the Young's modulus of the supporting glass substrate is preferably increased by 0.01 to 5 GPa, more preferably by 0.1 to 4 GPa, and further by 0.5 to 3 GPa. It is particularly preferable to increase the Young's modulus by 1 to 2 GPa. If the increase in the Young's modulus of the supporting glass substrate due to the heat treatment is too small, there is a possibility that the provision of the heat treatment step may become meaningless.

The method for manufacturing a supporting glass substrate of the present invention preferably includes a heat treatment step of heat-treating the supporting glass substrate after molding to increase the density of the supporting glass substrate. This heat treatment can be performed concurrently with heat treatment for increasing Young's modulus. In this way, when the density of the supporting glass substrate needs to be strictly adjusted, it becomes easier to control the density of the supporting glass substrate within the management target range. It is also possible to reduce the density of the supporting glass substrate by heat treatment. Efficiency tends to decrease.

In the manufacturing method of the supporting glass substrate of the present invention, it is preferable to heat-treat the supporting glass substrate after molding so that the Young's modulus of the supporting glass substrate falls within the control target range. This can reduce variations in the Young's modulus of the supporting glass substrate between manufacturing lots. As a result, the quality of the supporting glass substrate can be stabilized.

The range of increase in the Young's modulus of the supporting glass substrate due to heat treatment correlates with the range of increasing the density of the supporting glass substrate. Therefore, by measuring the increase value of the density of the supporting glass substrate, the increasing value of the Young's modulus of the supporting glass substrate can be easily estimated.

The heat treatment increases the density of the supporting glass substrate by preferably 0.001 to 0.05 g/cm ³ , more preferably 0.004 to 0.03 g/cm ³ , more preferably 0.007 to 0.015 g/cm 3 . An increase of ³ is particularly preferred. If the increase in density is too small, the increase in Young's modulus of the supporting glass substrate will also be small, and there is a possibility that the provision of the heat treatment step will be meaningless.

The maximum temperature of the heat treatment is preferably above (the strain point of the supporting glass substrate -100) ° C., (the strain point of the supporting glass substrate -50) ° C. or higher, or (the strain point of the supporting glass substrate -30) ° C. or higher. above the strain point of the supporting glass substrate, (the strain point of the supporting glass substrate +10) ° C. or higher, (the strain point of the supporting glass substrate +20) ° C. or higher, (the strain point of the supporting glass substrate +30) ° C. or higher, especially (the strain point of the supporting glass substrate +50 ) °C or higher. If the maximum heat treatment temperature is too low, the heat treatment time for increasing the Young's modulus of the supporting glass substrate will be unduly long, and heat treatment efficiency will tend to decrease. On the other hand, if the maximum heat treatment temperature is too high, the support glass substrate is likely to be thermally deformed. Therefore, the maximum temperature of the heat treatment is preferably (the strain point of the supporting glass substrate +150)° C. or lower and (the strain point of the supporting glass substrate +120)° C. or lower.

In the heat treatment step, the temperature is preferably lowered from the maximum heat treatment temperature in order to safely remove the supporting glass substrate from the heat treatment furnace. The temperature drop rate is preferably 5°C/min or less, 4°C/min or less, 3°C/min or less, 2°C/min or less, 1°C/min or less, and particularly 0.8°C/min or less. If the cooling rate is too fast, thermal strain tends to remain in the support glass substrate after the heat treatment process, and the support glass substrate may be damaged when it is taken out from the heat treatment furnace. On the other hand, if the temperature drop rate is too slow, the heat treatment time for increasing the Young's modulus of the supporting glass substrate becomes unduly long, and heat treatment efficiency tends to decrease. Therefore, the temperature drop rate is preferably 0.01°C/min or more, 0.05°C/min or more, 0.1°C/min or more, 0.2°C/min or more, and particularly 0.5°C/min or more. .

It is preferable to prepare a heat treatment setter larger than the size of the support glass substrate, place the formed support glass substrate on the heat treatment setter, and then subject it to the heat treatment step. In this way, temperature unevenness of the supporting glass substrate can be reduced during the heat treatment. If the size of the heat treatment setter is equal to or smaller than the size of the support glass substrate, part of the support glass substrate tends to protrude from the heat treatment setter, and the protruding portion is likely to be thermally deformed.

In the manufacturing method of the supporting glass substrate of the present invention, it is preferable to reduce the amount of warpage of the supporting glass substrate to 40 μm or less by heat treatment. In order to reduce the amount of warping of the supporting glass substrate, it is preferable to place a heat-resistant substrate above the supporting glass substrate and perform the heat treatment while sandwiching the supporting glass substrate between the heat-treating setter and the heat-resistant substrate. A mullite substrate, an alumina substrate, or the like can be used as the heat-resistant substrate. Moreover, it is preferable to heat-process in the state which laminated|stacked the support glass substrate of several sheets. As a result, the amount of warping of the support glass substrates laminated below the lamination is appropriately reduced by the mass of the support glass substrates laminated above. Furthermore, the heat treatment efficiency of the supporting glass substrate can be enhanced.

The method for manufacturing a supporting glass substrate of the present invention preferably includes a polishing step of polishing the surface of the supporting glass substrate to reduce the total plate thickness deviation to less than 2.0 μm after the heat treatment step. Various methods can be employed for the polishing treatment. The support glass substrate is polished by sandwiching the support glass substrate between a pair of polishing pads and rotating the support glass substrate and the pair of polishing pads together. A method of processing is preferred. Further, it is preferable that the pair of polishing pads have different outer diameters, and it is preferable that the supporting glass substrate is intermittently polished so that a part of the supporting glass substrate protrudes from the polishing pads during polishing. As a result, it becomes easier to reduce the total plate thickness deviation, and it becomes easier to reduce the amount of warpage. In addition, in the polishing process, the polishing depth is not particularly limited, but the polishing depth is preferably 50 μm or less, 30 μm or less, 20 μm or less, and particularly 10 μm or less. As the polishing depth is smaller, the productivity of the supporting glass substrate is improved.

It is preferable to polish the surface of the supporting glass substrate so that the total thickness deviation (TTV) of the supporting glass substrate is less than 2.0 μm, 1 μm or less, particularly 0.1 to less than 1 μm. It is preferable to polish the surface of the support glass substrate so that the arithmetic mean roughness Ra is 5 nm or less, 2 nm or less, 1.5 nm or less, 1 nm or less, 0.8 nm or less, particularly 0.5 nm or less. The smaller the total plate thickness deviation (TTV) or the higher the surface accuracy, the easier it is to improve the accuracy of processing. In particular, since wiring accuracy can be improved, high-density wiring becomes possible. Moreover, the strength of the supporting glass substrate is improved, and the supporting glass substrate and the laminated substrate are less likely to break. The "arithmetic mean roughness Ra" can be measured with an atomic force microscope (AFM).

The method for manufacturing a supporting glass substrate of the present invention preferably includes a cutting and removing step of cutting and removing the peripheral portion of the supporting glass substrate after the heat treatment step. It is further preferable to include a cutting and removing step of cutting and removing the peripheral portion of the glass substrate. In the heat treatment process, the peripheral portion of the support glass substrate tends to warp more than the central portion. Therefore, if the peripheral portion of the supporting glass substrate is cut off after the heat treatment process, the amount of warping of the supporting glass substrate can be reduced.

When cutting and removing the peripheral portion of the support glass substrate, it is preferable to cut out a substantially disk-shaped or wafer-shaped portion from the rectangular support glass substrate. In this way, it becomes easy to apply to the manufacturing process of the semiconductor package. If necessary, it may be processed into a shape other than that, such as a rectangular shape. The roundness of the cut support glass substrate (excluding notch portions) is preferably 1 mm or less, 0.1 mm or less, 0.05 mm or less, and particularly 0.03 mm or less. The smaller the circularity, the easier it is to apply to the semiconductor package manufacturing process. The “circularity (excluding the notch portion)” refers to a value obtained by subtracting the minimum value from the maximum value of the wafer diameter (excluding the notch portion).

The method for manufacturing a supporting glass substrate of the present invention preferably includes a notching step of forming a notch portion (alignment portion) in a part of the outer circumference of the supporting glass substrate after the cutting and removing step. In this way, the position of the support glass substrate can be easily fixed by bringing the positioning member such as the positioning pin into contact with the notch portion of the support glass substrate. As a result, alignment between the processing substrate and the supporting glass substrate is facilitated. If a notch portion is also formed in the processing substrate and the positioning member is brought into contact with the processing substrate, the alignment between the processing substrate and the supporting glass substrate becomes even easier.

The method for manufacturing a supporting glass substrate of the present invention preferably includes a chamfering step of chamfering the end face (including the end face of the notch portion) of the supporting glass substrate after the cutting and removing step. This makes it easier to prevent damage from the end surface of the supporting glass substrate. For chamfering, chamfering using a grooved whetstone, chamfering by acid etching such as hydrofluoric acid, or the like can be adopted.

In the method for producing a supporting glass substrate of the present invention, it is preferable not to subject the supporting glass substrate to ion exchange treatment. The ion exchange treatment increases the production cost of the supporting glass substrate and makes it difficult to reduce the total thickness deviation (TTV) of the supporting glass substrate.

A method for manufacturing a semiconductor package according to the present invention includes a lamination step of fabricating a laminated substrate including at least a processed substrate and a supporting glass substrate for supporting the processed substrate, and processing of processing the processed substrate of the laminated substrate. and a processing step, and the support glass substrate is manufactured by the above-described method for manufacturing a support glass substrate. The technical features of the semiconductor package manufacturing method of the present invention overlap with the technical features of the supporting glass substrate manufacturing method of the present invention. Therefore, in this specification, for the sake of convenience, detailed descriptions of the overlapping portions are omitted.

In the method for manufacturing a semiconductor package of the present invention, it is preferable to provide an adhesive layer between the processing substrate and the support glass substrate. The adhesive layer is preferably made of a resin, such as a thermosetting resin, a photocurable resin (particularly an ultraviolet curable resin), or the like. Moreover, it is preferable to have heat resistance to withstand heat treatment in the manufacturing process of the semiconductor package. As a result, the adhesive layer is less likely to melt during the manufacturing process of the semiconductor package, and the accuracy of processing can be improved. In addition, in order to easily fix the processing substrate and the supporting glass substrate, an ultraviolet curing tape can also be used as an adhesive layer.

Furthermore, it is preferable to provide a release layer between the processing substrate and the supporting glass substrate, more specifically between the processing substrate and the adhesive layer. In this way, the processed substrate can be easily separated from the supporting glass substrate after the predetermined processing is performed on the processed substrate. From the viewpoint of productivity, the peeling of the substrate to be processed is preferably performed by irradiation light such as laser light. As a laser light source, an infrared laser light source such as a YAG laser (wavelength 1064 nm) or a semiconductor laser (wavelength 780 to 1300 nm) can be used. Also, a resin that decomposes when irradiated with an infrared laser can be used for the release layer. Also, a substance that efficiently absorbs infrared rays and converts them into heat can be added to the resin. For example, carbon black, graphite powder, fine metal powder, dyes, pigments, etc. can be added to the resin.

The peeling layer is composed of a material that causes "intralayer peeling" or "interfacial peeling" by irradiation light such as laser light. That is, when irradiated with light of a certain intensity, the bonding force between atoms or molecules disappears or decreases, causing ablation or the like, and is made of a material that causes peeling. In addition, when irradiated with irradiation light, the components contained in the peeling layer are released as gas, leading to separation, and when the peeling layer absorbs light, becomes gaseous, and the vapor is released, leading to separation. There is.

In the method of manufacturing a semiconductor package of the present invention, it is preferable that the size of the processed substrate is larger than the size of the supporting glass substrate. As a result, when the processing substrate and the supporting glass substrate are laminated, even if the centers of the substrates are slightly separated from each other, the edges of the processing substrate are less likely to protrude from the supporting glass substrate.

Preferably, the method for manufacturing a semiconductor package of the present invention further includes a transporting step of transporting the laminated substrate. Thereby, the processing efficiency of processing can be improved. It should be noted that the "conveyance process" and the "processing process" do not necessarily have to be performed separately, and may be performed at the same time.

In the manufacturing method of the semiconductor package of the present invention, the processing is preferably a processing of wiring on one surface of the processed substrate or a processing of forming solder bumps on one surface of the processed substrate. In the method of manufacturing a semiconductor package according to the present invention, warping of the processed substrate is less likely to occur during these processes, so these processes can be performed properly.

In addition to the above, processing treatments include mechanically polishing one surface of the processing substrate (usually the surface opposite to the supporting glass substrate), one surface of the processing substrate (usually the supporting glass substrate) It may be either a process of dry-etching the opposite surface) or a process of wet-etching one surface of the processing substrate (generally, the surface opposite to the supporting glass substrate). In the method of manufacturing a semiconductor package according to the present invention, warping of the processed substrate is less likely to occur, so the above-described processing can be performed properly.

The present invention will be further described with reference to the drawings.

FIG. 1 is a conceptual perspective view showing an example of a laminated substrate 1 according to the present invention. In FIG. 1 , the laminated substrate 1 comprises a support glass substrate 10 and a processing substrate 11 . The supporting glass substrate 10 is adhered to the processing substrate 11 in order to prevent the processing substrate 11 from warping. A release layer 12 and an adhesive layer 13 are arranged between the supporting glass substrate 10 and the processing substrate 11 . The release layer 12 is in contact with the support glass substrate 10 and the adhesive layer 13 is in contact with the processing substrate 11 .

As can be seen from FIG. 1, in the laminated substrate 1, a supporting glass substrate 10, a peeling layer 12, an adhesive layer 13, and a processing substrate 11 are laminated in this order. The shape of the supporting glass substrate 10 is determined depending on the processing substrate 11. In FIG. 1, both the supporting glass substrate 10 and the processing substrate 11 have a substantially disk shape. For the release layer 12, for example, a resin that decomposes when irradiated with a laser can be used. Also, a substance that efficiently absorbs laser light and converts it into heat can be added to the resin. Examples include carbon black, graphite powder, fine metal powder, dyes and pigments. The release layer 12 is formed by plasma CVD, spin coating by a sol-gel method, or the like. The adhesive layer 13 is made of resin, and is formed by applying various methods such as printing, inkjet, spin coating, and roll coating. Ultraviolet curable tape can also be used. The adhesive layer 13 is dissolved and removed with a solvent or the like after the support glass substrate 10 is separated from the processing substrate 11 by the release layer 12 . The UV curable tape can be removed with a peeling tape after being irradiated with UV rays.

FIG. 2 is a conceptual cross-sectional view showing a chip-first type manufacturing process of a fan-out type WLP. FIG. 2(a) shows a state in which an adhesive layer 21 is formed on one surface of the support member 20. FIG. A release layer may be formed between the support member 20 and the adhesive layer 21 as necessary. Next, as shown in FIG. 2B, a plurality of semiconductor chips 22 are attached onto the adhesive layer 21 . At that time, the active side surface of the semiconductor chip 22 is brought into contact with the adhesive layer 21 . Next, as shown in FIG. 2C, the semiconductor chip 22 is molded with a resin sealing material 23 . The sealing material 23 is made of a material that causes less dimensional change after compression molding and less dimensional change when wiring is formed. Subsequently, as shown in FIGS. 2(d) and 2(e), after separating the processing substrate 24 on which the semiconductor chip 22 is molded from the supporting member 20, it is adhesively fixed to the supporting glass substrate 26 via the adhesive layer 25. Let At this time, of the surfaces of the processed substrate 24 , the surface opposite to the surface on which the semiconductor chip 22 is embedded is arranged on the support glass substrate 26 side. Thus, the laminated substrate 27 can be obtained. A peeling layer may be formed between the adhesive layer 25 and the support glass substrate 26 as necessary. Furthermore, after transporting the obtained laminated substrate 27, as shown in FIG. to form Finally, after the processing substrate 24 is separated from the supporting glass substrate 26, the processing substrate 24 is cut into individual semiconductor chips 22, which are subjected to the subsequent packaging process. Further, the supporting glass substrate 26 is subjected to acid treatment with HF, HCl, etc., and alkali treatment with NaOH, KOH, etc., and then reused (FIG. 2(g)).

EXAMPLES The present invention will be described below based on examples. It should be noted that the following examples are merely illustrative. The present invention is by no means limited to the following examples.

Tables 1 to 5 show examples of the present invention (samples No. 1, 2, 4, 5, 7, 8, 10, 11, 13, 14) and comparative examples (samples No. 3, 6, 9, 12, 15).

Sample no. Glass substrates according to 1 to 3 (glass substrates before heat treatment) were produced. First, as a glass composition, in mass %, SiO ₂ 65.6%, Al ₂ O ₃ 8.0%, B ₂ O ₃ 9.1%, Na ₂ O 12.8%, CaO 3.1%, ZnO After preparing and mixing the glass raw materials so as to contain 0.9%, SnO ₂ 0.3%, and Sb ₂ O ₃ 0.1% to obtain a glass batch, it is supplied to a glass melting furnace at 1550 ° C. Then, the resulting molten glass was clarified, stirred, and supplied to a forming apparatus for an overflow downdraw method to form a plate having a thickness of 0.7 mm. After that, the obtained glass substrate was cut into a rectangular shape. The strain point of the obtained glass substrate was measured by the method described in ASTM C336 and found to be 519°C.

Sample no. Glass substrates according to 4 to 6 (glass substrates before heat treatment) were produced. First, as the glass composition, in mass %, SiO ₂ 61.63%, Al ₂ O ₃ 18.0%, B ₂ O ₃ 0.5%, Na ₂ O 14.5%, K ₂ O 2.01% , MgO 3.0%, BaO 0.01%, and SnO ₂ 0.35%. After melting, the resulting molten glass was clarified, stirred, and supplied to a forming apparatus for an overflow down-draw method to form a plate having a thickness of 1.05 mm. After that, the obtained glass substrate was cut into a rectangular shape. The strain point of the obtained glass substrate was measured by the method described in ASTM C336 and found to be 567°C.

Sample no. Glass substrates (glass substrates before heat treatment) according to Nos. 7 to 9 were produced. First, as the glass composition, in mass %, SiO ₂ 65.8%, Al ₂ O ₃ 8.0%, B ₂ O ₃ 3.7%, Na ₂ O 18.1%, CaO 3.2%, ZnO After preparing and mixing the glass raw materials to contain 0.9% SnO ₂ 0.3% and obtaining a glass batch, it is fed to a glass melting furnace and melted at 1300 ° C. After refining and stirring the glass, it was supplied to a molding apparatus for the overflow down-draw method and molded to a thickness of 0.7 mm. After that, the obtained glass substrate was cut into a rectangular shape. The strain point of the obtained glass substrate was measured by the method described in ASTM C336 and found to be 530°C.

Sample no. Glass substrates (glass substrates before heat treatment) according to Nos. 10 to 12 were produced. First, as the glass composition, in mass %, SiO ₂ 65.7%, Al ₂ O ₃ 8.0%, B ₂ O ₃ 2.1%, Na ₂ O 19.8%, CaO 3.2%, ZnO After preparing and mixing the glass raw materials to contain 0.9% SnO ₂ 0.3% and obtaining a glass batch, it is fed to a glass melting furnace and melted at 1700 ° C. After refining and stirring the glass, it was supplied to a molding apparatus for the overflow down-draw method and molded to a thickness of 1.05 mm. After that, the obtained glass substrate was cut into a rectangular shape. The strain point of the obtained glass substrate was measured by the method described in ASTM C336 and found to be 515°C.

Sample no. Glass substrates (glass substrates before heat treatment) according to Nos. 13 to 15 were produced. First, as the glass composition, in mass %, SiO ₂ 65.3%, Al ₂ O ₃ 8.0%, Na ₂ O 22.3%, CaO 3.2%, ZnO 0.9%, SnO ₂ 0.9%. After preparing and mixing the glass raw materials so as to contain 3% and obtaining a glass batch, it is supplied to a glass melting furnace and melted at 1700 ° C., then the obtained molten glass is clarified and stirred, It was supplied to a forming apparatus for an overflow downdraw method, and formed to have a plate thickness of 1.05 mm. After that, the obtained glass substrate was cut into a rectangular shape. The strain point of the obtained glass substrate was measured by the method described in ASTM C336 and found to be 497°C.

Subsequently, a setter for heat treatment larger than the size of the glass substrate after cutting is prepared, the glass substrate is placed on the setter for heat treatment, a heat-resistant substrate is further placed on the glass substrate, and this lamination is performed. The substrate was put into an electric furnace. Next, the temperature inside the electric furnace was raised to the maximum temperature shown in the table, and after the maximum temperature was maintained for the time shown in the table, the temperature inside the electric furnace was lowered at the cooling rate shown in the table. In addition, sample no. 3, 6, 9, 12, and 15 were not subjected to the heat treatment.

The obtained glass substrate was measured for Young's modulus and rigidity using a commercially available Young's modulus and rigidity measurement device (free resonance elastic modulus measurement device JE-RT3 manufactured by Technoplus Japan Co., Ltd.).

Furthermore, the density of the obtained glass substrate was measured by the Archimedes method.

As is clear from Tables 1 to 5, sample no. In Nos. 1, 2, 4, 5, 7, 8, 10, 11, 13, and 14, the Young's modulus could be increased by the predetermined heat treatment.

Furthermore, after the heat-treated glass substrate (Samples No. 1, 2, 4, 5, 7, 8, 10, 11, 13, 14: total plate thickness deviation of about 4.0 μm) was hollowed out to φ300 mm, the glass substrate Both surfaces were polished by a polishing machine. Specifically, both surfaces of the glass substrate were sandwiched between a pair of polishing pads having different outer diameters, and both surfaces of the glass substrate were polished while rotating the glass substrate and the pair of polishing pads together. During the polishing process, it was controlled so that part of the glass substrate protruded from the polishing pad from time to time. The polishing pad was made of urethane, the average particle size of the polishing slurry used in the polishing process was 2.5 μm, and the polishing speed was 15 m/min. For each of the resulting polished glass substrates, the overall plate thickness deviation and the amount of warpage were measured using a Bow/Warp measuring device SBW-331ML/d manufactured by Kobelco Research Institute. As a result, the total plate thickness deviation was less than 1.0 μm, and the amount of warpage was 35 μm or less.

1, 27 Laminated substrates 10, 26 Supporting glass substrates 11, 24 Processing substrate 12 Separation layers 13, 21, 25 Adhesive layer 20 Supporting member 22 Semiconductor chip 23 Sealing material 28 Wiring 29 Solder bump

Claims (16)

In a method for manufacturing a supporting glass substrate for supporting a processed substrate,
A molding step of molding a supporting glass substrate, and a heat treatment step of heat-treating the supporting glass substrate after molding to increase the Young's modulus of the supporting glass substrate,
The maximum temperature of the heat treatment is (the strain point of the supporting glass substrate + 83 ° C.) or less,
A method for producing a supporting glass substrate, comprising heat-treating the supporting glass substrate after molding so that the Young's modulus of the supporting glass substrate falls within a control target range. 2. The method for producing a supporting glass substrate according to claim 1, wherein the maximum temperature of the heat treatment is (+28[deg.] C. strain point of the supporting glass substrate) or less. 3. The method for producing a supporting glass substrate according to claim 1, wherein the maximum temperature of the heat treatment is higher than (the strain point of the supporting glass substrate -100)°C. 4. The method for producing a supporting glass substrate according to claim 1, wherein the heat treatment temperature is lowered at a rate of 5° C./min or less after reaching the maximum heat treatment temperature. 5. The method for producing a supporting glass substrate according to claim 1, wherein the amount of warp of the supporting glass substrate is reduced to 40 μm or less by heat treatment. 6. The method according to any one of claims 1 to 5, wherein a heat treatment setter larger than the size of the support glass substrate is prepared, and after the support glass substrate after molding is placed on the heat treatment setter, the support glass substrate is subjected to the heat treatment step. The method for manufacturing the supporting glass substrate according to 1. 7. The method for producing a supporting glass substrate according to claim 1, wherein the supporting glass substrate is formed so that the thickness is 400 μm or more and less than 2 mm. 8. The method for producing a supporting glass substrate according to any one of claims 1 to 7, wherein the supporting glass substrate is formed by an overflow down-draw method. 9. The method for manufacturing a supporting glass substrate according to any one of claims 1 to 8, further comprising a step of measuring an increase in density after the heat treatment step. The support according to any one of claims 1 to 9, further comprising a polishing step of polishing the surface of the supporting glass substrate to reduce the total plate thickness deviation (TTV) to less than 2.0 µm after the heat treatment step. A method for manufacturing a glass substrate. 11. The method for producing a supporting glass substrate according to any one of claims 1 to 10, further comprising a step of cutting and removing a peripheral portion of the supporting glass substrate after the heat treatment step. The method for manufacturing a semiconductor package according to any one of claims 1 to 11, wherein the maximum temperature of the heat treatment is 650°C or less. a lamination step of fabricating a laminated substrate comprising at least a processed substrate and a supporting glass substrate for supporting the processed substrate;
and a processing step of processing the processed substrate of the laminated substrate,
A method for manufacturing a semiconductor package, wherein the supporting glass substrate is manufactured by the method for manufacturing a supporting glass substrate according to any one of claims 1 to 12. 14. The method of manufacturing a semiconductor package according to claim 13, wherein the processing substrate comprises at least a semiconductor chip molded with a sealing material. 15. The method of manufacturing a semiconductor package according to claim 13, wherein the processing includes wiring on one surface of the processed substrate. 16. The method of manufacturing a semiconductor package according to claim 13, wherein the processing includes forming solder bumps on one surface of the processed substrate.

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