TWI762489B - Disc-shaped glass and method of making the same - Google Patents

Abstract

The manufacturing method of the disc-shaped glass of the present invention is characterized by comprising: a heat treatment process in which a glass plate is heated from room temperature to a temperature range of -50°C to a cool point +80°C. The pre-set peak temperature is followed by cooling; and the circular cutting process, which is to cut the disk-shaped glass from the glass plate. In the manufacturing method of the disc-shaped glass of the present invention, it is preferable that the heat treatment process comprises: a heating step, which is to raise the temperature from room temperature to a peak temperature at a speed of +1~+16°C/min; a holding step, which is After the heating step, the holding temperature in the range of the peak temperature -10°C to the peak temperature is maintained for 0 to 120 minutes; and the cooling step is after the holding step, from the holding temperature to the strain point of the glass plate -50°C In the temperature range of , the temperature is lowered at a rate of -6.0~-0.3℃/min.

Description

Disc-shaped glass and method of making the same

The present invention relates to a disk-shaped glass and a method for producing the same, and more specifically, relates to a glass-disc-shaped glass that is used as a support processing substrate in a manufacturing process of a semiconductor package, and a method for producing the same.

In a semiconductor manufacturing process, a disk-shaped semiconductor supporting glass substrate is used as a member for supporting the semiconductor substrate. The glass substrate for semiconductor support requires high flatness to support the semiconductor substrate stably. In response to the above-mentioned requirements, a technique for improving the flatness of the glass substrate for semiconductor support by polishing the main plane surface has been developed (for example, Patent Document 1).

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2014-517805

However, it is difficult to fully improve the flatness of a glass substrate only by grinding|polishing. Specifically, in a preliminarily thin glass plate, there is little margin for grinding, and it is difficult to sufficiently flatten it. Moreover, when grinding|polishing the glass plate shape|molded comparatively thick, since the grinding|polishing amount becomes large, there exists a problem that manufacturing cost increases significantly.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a disk-shaped glass with high flatness, and a method for producing the disk-shaped glass with ease.

The manufacturing method of the disc-shaped glass of the present invention is characterized by comprising: a heat treatment process in which a glass plate is heated from room temperature to a temperature range of -50°C to a cool point +80°C. The pre-set peak temperature is followed by cooling; and the circular cutting process, which is to cut the disk-shaped glass from the glass plate.

In the manufacturing method of the disc-shaped glass of the present invention, it is preferable that the heat treatment process comprises: a heating step, which is to raise the temperature from room temperature to a peak temperature at a speed of +1~+16°C/min; a holding step, which is After the heating step, the holding temperature in the range of the peak temperature -10°C to the peak temperature is maintained for 0 to 120 minutes; and the cooling step is after the holding step, from the holding temperature to the strain point of the glass plate -50°C In the temperature range of , the temperature is lowered at a rate of -6.0~-0.3℃/min.

In the manufacturing method of the disc-shaped glass of the present invention, it is preferable that the cooling step includes: a first cooling step, which is in the temperature range from the holding temperature to the strain point of the glass plate at -50°C, at a temperature of -3.0~ Cooling at a speed of -0.3°C/min; and a second cooling step, which is in a temperature region below the strain point -50°C, cooling at a speed of -5.8~-1.1°C/min.

In the manufacturing method of the disc-shaped glass of this invention, it is preferable to heat-process in the state which applied the load to the plate-glass thickness direction in a heat-processing process.

In the manufacturing method of the disc-shaped glass of the present invention, it is preferable that a plurality of glass plates are laminated with a release material interposed therebetween, and the heat treatment process of the heat treatment process is performed with the pressing member placed on the uppermost stage.

In the manufacturing method of the disc-shaped glass of the present invention, it is preferable to additionally arrange a supporting member at the lowermost stage of the plurality of glass plates, so that the contact surface of each of the pressing member and the supporting member with the glass plate is larger than the main surface of the glass plate . The main surface of a glass plate as used here means the surface which opposes the thickness direction of a glass plate.

In the manufacturing method of the disc-shaped glass of the present invention, it is preferable to further include a grinding process, which is performed after the heat treatment process and either before or after the circular cutting process, to grind the two main surfaces of the glass plate. Polishing is performed, and the polishing amount of the other main surface is within the range of 0.8 to 1.2 times the polishing amount of the one main surface.

In the manufacturing method of the disk-shaped glass of the present invention, it is preferable to perform a circular cutting process after the heat treatment process, and to include a slit forming process, which is formed on the disk-shaped glass plate after the circular cutting process. incision part.

50mm，端部係指離端面為100mm內側的部分。 The disc-shaped glass of the present invention is characterized in that the warpage is 200 μm or less, and the difference in stress between the glass surface at the center and the edge is 0 to 10 MPa. The center referred to herein refers to the center of the substrate

50mm, the end refers to the part that is 100mm inside from the end face.

The disk-shaped glass of the present invention is preferably formed into a bowl shape in a region within 0.8r from the center when the radius is set to r (mm).

It is preferable that the disk-shaped glass of this invention has a marking on the main surface which becomes the upper surface at the time of use, and has the bowl shape which recessed the main surface side on which the marking was formed.

The disc-shaped glass of the present invention is preferably formed into a saddle shape.

It is preferable that the disc-shaped glass of this invention has a notch part.

According to the present invention, a disk-shaped glass with high flatness and a manufacturing method for easily obtaining the disk-shaped glass can be provided.

G1‧‧‧glass plate

G3, G4‧‧‧Disc glass

U‧‧‧Laminate

T‧‧‧heat treatment device

M‧‧‧Conveyor

H‧‧‧heat treatment furnace

P1‧‧‧Support Components

P2‧‧‧Pressing member

N‧‧‧Incision

FIG. 1 is a view showing an example of the sequence of the manufacturing method of the disk-shaped glass according to the embodiment of the present invention.

FIG. 2 is a diagram showing an example of the structure of the laminate according to the embodiment of the present invention.

FIG. 3 is a diagram showing an example of the configuration of the heat treatment apparatus according to the embodiment of the present invention.

FIG. 4 is a graph showing an example of the heat treatment conditions in the embodiment of the present invention.

FIG. 5 is a graph showing an example of the heat treatment conditions in the embodiment of the present invention.

FIG. 6 is a graph showing an example of the heat treatment conditions in the embodiment of the present invention.

Fig. 7 is a view showing an example of the disk-shaped glass according to the embodiment of the present invention.

FIG. 8 is a view showing an example of the disc-shaped glass having a cutout part according to the embodiment of the present invention.

FIG. 9A is an enlarged view of an example of the plan view shape of the disk-shaped glass having the bowl shape according to the embodiment of the present invention.

9B is an enlarged view of an example of a three-dimensional oblique view of the disk-shaped glass having a bowl shape according to the embodiment of the present invention.

Fig. 10A is an enlarged view of an example of a plan view shape of a disc-shaped glass having a saddle shape according to an embodiment of the present invention.

Fig. 10B is an enlarged view showing an example of a three-dimensional oblique view of the disk-shaped glass having a saddle shape according to the embodiment of the present invention.

Fig. 11A is an enlarged view of an example of a plan view shape of the disk-shaped glass having a valley shape according to the embodiment of the present invention.

11B is an enlarged view showing an example of a three-dimensional oblique view of the disc-shaped glass having a valley shape according to the embodiment of the present invention.

Hereinafter, the disk-shaped glass and the manufacturing method thereof according to the embodiment of the present invention will be described. The disk-shaped glass G4 according to the embodiment of the present invention is a substantially circular glass substrate in plan view (see FIG. 8 ) having a notch portion N, and is used, for example, as a support substrate for supporting a semiconductor substrate.

First, the manufacturing method of the disk-shaped glass G4 which concerns on embodiment of this invention is demonstrated based on FIGS. 1-8. 1 : is a figure which shows an example of the sequence of the manufacturing method of the disk-shaped glass G4 which concerns on embodiment of this invention. The manufacturing method of the disk-shaped glass G4 which concerns on embodiment of this invention is equipped with the glass plate preparation process S1, the heat treatment process S2, the circular cutting process S3, and the notch formation process S4.

The glass plate preparation process S1 is a process of preparing the glass plate G1 which is the basis of the disk-shaped glass G4. The glass plate G1 may be a glass plate having a size sufficient to cut out the disk-shaped glass G4. Specifically, the glass plate G1 is, for example, a rectangular shape, preferably a substantially square plate shape. The thickness of the glass plate G1 is preferably less than 2.0 mm, 1.5 mm or less, 1.2 mm or less, 1.1 mm or less, 1.0 mm or less, particularly 0.9 mm or less. Moreover, it is preferable that the plate thickness of the glass plate G1 is 0.1 mm or more, 0.2 mm or more, 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, 0.6 mm or more, and especially more than 0.7 mm.

The glass plate G1 may be glass having an arbitrary composition according to the application. The composition of the glass plate G1 is preferably adjusted in advance so that the disk-shaped glasses G3 and G4 become the composition described later.

The glass plate G1 is formed by using the overflow down-draw method to shape the molten glass obtained by melting, for example, the glass raw material prepared into the above-mentioned composition into a plate shape. However, the above-mentioned forming method is an example, and any conventionally known methods such as a floating method, a flattening method, and a slit drawing method can also be used.

In this embodiment, the process of the heat treatment process S2 is performed following the glass plate preparation process S1 mentioned above.

In the heat treatment process S2, the glass plate G1 prepared in the said glass plate preparation process S1 is heat-processed, and the heat-treated glass plate G2 (not shown) is obtained. Specifically, the glass plate G1 is cooled after being heated from room temperature to a predetermined peak temperature in the range from -50°C to the cool point +80°C. However, in this invention, room temperature means the temperature in the range of 0-45 degreeC. The warpage of the heat-treated glass plate G2 and the disk-shaped glasses G3 and G4 obtained by the heat-treated glass plate G2 can be appropriately reduced by the above-described treatment. Here, if the peak temperature is less than the cold point of -50°C, the heat treatment will be insufficient, and it is difficult to properly reduce the warpage of the disk-shaped glasses G3 and G4. If the peak temperature exceeds the cold point +80°C, excessive heat treatment will occur. , it is estimated that concave defects (eg, ellipse with a depth of 10 μm or more and a major axis of 200 μm or more) due to heat treatment are likely to occur on the main surfaces of the disk-shaped glasses G3 and G4 .

More specifically, the heat treatment process S2 includes a temperature increase step S21, a holding step S22, and a temperature decrease step S23. In the temperature raising step S21, preferably, the glass plate G1 is heated from room temperature to the peak temperature at a speed of +1~+16°C/min. In the holding step S22, it is preferable to hold the glass plate G1 for 0 to 120 minutes at a holding temperature within the range from the peak temperature to the peak temperature after the temperature increase step S21. In the cooling step S23, preferably after the holding step S22, the glass plate G1 is heated in the temperature range from the holding temperature to the strain point of the glass plate G1 -50°C at a speed of -6.0~-0.3°C/min Cool down.

In addition, the cooling step S23 preferably includes a first cooling step S23A and a second cooling step S23B with different cooling speeds. Preferably, the cooling speed of the first cooling step S23A on the high temperature side is slower than that of the second cooling step S23B on the low temperature side. In the first cooling step S23A, preferably in the temperature range from the holding temperature in the holding step S22 to the strain point of the glass plate G1 -50°C, the glass plate is cooled at a speed of -3.0~-0.3°C/min. G1 cools down. In the second cooling step S23B, preferably after the first cooling step S23A, the temperature is lowered at a rate of -5.8~-1.1°C/min in a temperature region below the strain point -50°C.

In this embodiment, as shown in FIG. 2, the glass plate G1 is heat-processed in the state which laminated|stacked the laminated body U of several sheets. The layered body U system includes a support member P1, a plurality of glass plates G1, and a pressing member P2. The support member P1 and the pressing member P2 each have a contact surface that can come into contact with the entire surface of the main surface of the glass plate G1, and are heat-resistant members. The support member P1 and the pressing member P2 are, for example, plate-shaped or block-shaped refractories, preferably mullite-based refractories. The laminated body U is comprised so that the glass plate G1 which laminated|stacked several sheets is sandwiched between the support member P1 arrange|positioned at the lowermost stage, and the pressing member P2 arrange|positioned at the uppermost stage.

The heat treatment is performed in a state where a uniform load is applied to the glass plate G1 in the thickness direction by performing the heat treatment in the state of the laminate U as described above. The warpage of the plurality of glass plates G1 and the disc-shaped glasses G3 and G4 obtained from the glass plate G1 can be easily reduced by the above-mentioned treatment. In order to enjoy the above effects more reliably, it is preferable that the upper surface of the supporting member P1 as the contact surface (supporting surface) and the lower surface of the pressing member P2 as the contact surface (pressing surface) be larger than the glass plate G1. main surface. However, the contact surface of the support member P1 and the contact surface of the pressing member P2 may be the same size as the main surface of the glass plate G1, or may be smaller.

It is preferable that the glass plate G1 is laminated|stacked in the state which the mold release powder, such as talc powder, adhered to the surface. By adhering the mold release powder to the glass plate G1, it is possible to prevent the formation of defects on the glass surface during or after the heat treatment. Here, instead of adhering the mold release powder, it may be laminated with a mold release sheet such as alumina paper between each of the plurality of glass plates G1. It is preferable that these mold release powders and mold release sheets which are mold release materials are removed from the heat-treated glass plate G2 after heat treatment.

The treatment of the heat treatment step S2 can be performed using, for example, the heat treatment apparatus T shown in FIG. 3 . The heat treatment apparatus T includes a conveyor M and a heat treatment furnace H. The conveyor M is a conveying device that continuously conveys the layered body U, for example, a roller conveyor. The heat treatment furnace H is a heating device capable of controlling the internal temperature and gas environment. The heat treatment furnace H has a shape extending along the flow direction of the conveyor M, and a plurality of heat sources whose output can be individually adjusted in the extending direction are arranged. The laminated body U conveyed by the conveyor M is introduced into the heat treatment furnace H through the inlet provided at one end of the heat treatment furnace H, and after being heat treated in the furnace, it is led out through the outlet provided at the other end. out of the furnace. In the heat treatment apparatus T shown above, by adjusting the conveyance speed of the conveyor M and the output of each heat source of the heat treatment furnace H, the glass plate G1 can be heat treated under the temperature conditions of the above-mentioned steps.

For example, if the strain point of the glass plate G1 is 530°C and the slow cooling point is 570°C, the heat treatment can be performed under the temperature conditions shown in Figs. 4 to 6 . 4 to 6 are diagrams showing an example of temperature conditions in the heat treatment process of the present embodiment. In the graphs of FIGS. 4 to 6 , the horizontal axis represents time, and the vertical axis represents the temperature of the processing glass plate G1 . In the heat treatment shown in FIG. 4 , the temperature is first raised to a peak temperature of 620° C. at 10° C./min (heating step S21 ), maintained at the peak temperature for 90 minutes (holding step S22 ), and then lowered at -0.7° C./min. After reaching 400°C lower than 480°C which corresponds to the strain point -50°C (first cooling step S23A), the temperature is lowered to room temperature at -3.2°C/min (second cooling step S23B). In addition, in the heat treatment shown in FIG. 5, firstly, the temperature was raised to a peak temperature of 620°C at 15°C/min (heating step S21 ), maintained at the peak temperature for 20 minutes (holding step S22 ), and then at -1.1°C/min. After min cooling to 480°C which is equivalent to the strain point -50°C (first cooling step S23A), the temperature is lowered to room temperature at -4.8°C/min (second cooling step S23B). In the heat treatment shown in FIG. 6 , the temperature is first raised to a peak temperature of 590° C. at 14° C./min (heating step S21 ), maintained at the peak temperature for 20 minutes (holding step S22 ), and then lowered at -0.9° C./min. After reaching 480°C which corresponds to the strain point -50°C (first cooling step S23A), the temperature is lowered to room temperature at -3.2°C/min (second cooling step S23B). Here, the heat treatment shown in FIG. 5 and FIG. 6 is completed in a shorter time than the heat treatment shown in FIG. 4, and thus has the advantage of good manufacturing efficiency. In addition, according to an example of visual inspection under a fluorescent lamp, the occurrence rate of glass plates with surface defects obtained is 1.1% (302 pieces/28,000 pieces) in the heat treatment shown in FIG. 4, and shown in FIG. 5. 1.0% (292 pieces/28,000 pieces) in the heat treatment, and 0.3% (19 pieces/7,200 pieces) in the heat treatment shown in Fig. 6 . For the reason that surface defects are minimized in the heat treatment shown in FIG. 6 , it is considered that the peak temperature of the heat treatment shown in FIG. 6 is set to be lower than the peak temperature of the heat treatment shown in FIGS. 4 and 5 . .

Here, the above-mentioned heat treatment apparatus T is an example, and any apparatus may be used to perform the above-mentioned treatment. For example, a well-known electric furnace, a gas furnace, etc. may be used, and the said process may be performed continuously, and a batch type apparatus may be used for individual process.

The thermal contraction rate of the glass plate G1 before and after the process S2 after the heat treatment is preferably 20 ppm or less, preferably 15 ppm or less, 12 ppm or less, 10 ppm or less, especially 8 ppm or less.

In the present embodiment, the process of the circular cutting process S3 is performed following the heat treatment process S2.

In the circular cutting process S3, the disk-shaped glass G3 is cut out from the heat-treated glass plate G2 obtained in the above-mentioned heat-treatment process S2. Specifically, a circular scribe line is formed on one of the main surfaces of the heat-treated glass plate G2 using, for example, a diamond wafer or the like, and the scribe line is cut along the scribe line to obtain the disk-shaped glass G3 shown in FIG. 7 .

The size of the disc-shaped glass G3 can be arbitrarily set, but it is preferably a wafer shape (substantially circular shape) with a diameter of 100 to 500 mm, and particularly preferably 150 to 450 mm. If it is the shape shown above, it can be used suitably in the manufacturing process of a semiconductor package.

However, the above-mentioned cutting method is an example, and other arbitrary cutting methods may be used. For example, the heat-treated glass plate G2 may be cut into a circular shape by irradiating the heat-treated glass plate G2 with laser light to melt (laser melting), or by causing a crack (laser cutting) to cut the heat-treated glass plate G2 into a circular shape to obtain a disk shape. Glass G3. In addition, a circular mask may be formed on the main surface of the heat-treated glass plate G2, and the portion where the mask is not formed may be etched to obtain the disk-shaped glass G3.

Moreover, the end surface of the obtained disk-shaped glass G3 can also be processed arbitrarily. For example, the end face of the disk-shaped glass G3 may be chamfered by a grinding tool, etc., may be ground by a grinding tool, may be smoothed by heating by a laser beam, etc., or may be smoothed by hydrofluoric acid or the like Etching treatment.

Among them, when the amount of expansion or shrinkage of the glass sheet G1 is relatively large before and after the treatment of the heat treatment step S2, the treatment of the circular cutting step S3 is preferably performed after the heat treatment step S2 as described above. In the order shown above, after being cut into a disk shape, expansion and shrinkage are unlikely to occur, so that the disk-shaped glasses G3 and G4 with high dimensional accuracy can be easily obtained. On the other hand, when the amount of expansion or shrinkage of the glass sheet G1 before and after the treatment of the heat treatment step S2 is relatively small, or when the dimensional accuracy is ensured in the subsequent processing step, the processing of the circular cutting step may be performed first. After that, the heat treatment process is performed. That is, the process of the above-mentioned heat treatment process can also be performed in the state which laminated|stacked the disk-shaped glass.

In the present embodiment, the process of the notch forming process S4 is performed following the circular cutting process S3.

In the notch formation process S4, the notch part N is formed in the disk-shaped glass G3 obtained by the said circular cutting process S3, and the disk-shaped glass G4 shown in FIG. 8 is obtained. In the present embodiment, the notch portion N is, for example, a depression provided at the end of the disk-shaped glass G4. The notch part N can be formed by, for example, pushing a columnar rotary grinding tool against the end face of the disk-shaped glass G3. The notch portion N shown above is used for positioning the disk-shaped glass G4 in a semiconductor manufacturing process, or the like.

In addition, the shape of the said notch part N is an example, and the notch part of arbitrary shapes may be formed. For example, the notch part N may be the orientation plane which cut|disconnected the disk-shaped glass G3 on a straight line. In addition, a plurality of notches N may be provided in the same disk-shaped glass G4.

In addition, the notch part N and the outer peripheral end surface of the disk-shaped glass G4 can be processed arbitrarily. For example, the notch portion N and the end surface of the disk-shaped glass G3 may be chamfered by a grinding tool, ground by a grinding tool, smoothed by irradiating laser light, or smoothed by hydrofluoric acid. etc. to be etched.

However, if the notch portion N is not required in the semiconductor manufacturing process, the process of the notch forming process S4 may be omitted.

In addition, in the manufacturing method of the disk-shaped glass of this invention, the following process may be added arbitrarily to the said process.

For example, you may add the surface grinding|polishing process of grinding|polishing all or a part of the main surfaces of the disk-shaped glass G3, G4 after a circular cutting process. By the above-mentioned heat treatment process, the disc-shaped glass G3 and G4 have high flatness, but by grinding the main surface, it is easier to reduce the overall thickness variation, and it is also easy to reduce the amount of warpage. As a method of polishing, various methods can be used, but preferably a pair of polishing pads are sandwiched between both surfaces of the disc-shaped glass, and the disc-shaped glass is rotated together with the pair of polishing pads. A method of grinding glass. In addition, it is preferable that a pair of polishing pads have different outer diameters, and it is preferable to perform polishing treatment intermittently so that a part of the disk-shaped glass is exposed from the polishing pad during polishing. Thereby, it becomes easy to reduce the thickness variation of the whole board, and also it becomes easy to reduce the warpage amount. Among them, in the polishing treatment, 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. The smaller the grinding depth, the higher the productivity of the disc glass G3 and G4.

Moreover, you may add the strengthening process which chemically strengthens the whole or a part of the surface of the disk-shaped glass G3 and G4 by the ion exchange method. In addition, washing and drying processes may be added before and after each of the above-mentioned processes.

It is preferable that the disk-shaped glass G3, G4 obtained by the said method has the following characteristics.

The amount of warpage of the disk-shaped glasses G3 and G4 is preferably 40 μm or less, 30 μm or less, 25 μm or less, 1 to 20 μm, especially 5 to less than 20 μm. Further, the thickness variation of the heat-treated glass plate G2 and the disk-shaped glass G3 and G4 as a whole is preferably less than 2 μm, less than 1.5 μm, less than 1 μm, less than 1 μm, less than 0.8 μm, 0.1 to 0.9 μm, especially 0.2 to 0.7 μm . When the warpage amount is within the range shown above, the semiconductor can be favorably supported in the semiconductor manufacturing process, and the semiconductor can be manufactured with high productivity. Here, the "warpage amount" can be determined by the distance A between the highest position and the least square focal plane in the disk-shaped glasses G3 and G4 placed on the horizontal plane, as in the case of Warp in the semiconductor substrate, and The total (A+B) of the distances B between the lowest position and the least square plane is obtained. The amount of warpage can be measured by, for example, SBW-331ML/d manufactured by KOBELCO SCIENTIFIC CO., LTD.

The arithmetic mean roughness Ra of the surfaces of the disk-shaped glasses G3 and G4 is preferably 10 nm or less, 5 nm or less, 2 nm or less, 1 nm or less, particularly 0.5 nm or less. The smaller the arithmetic mean roughness Ra of the surface, the easier it is to improve the accuracy of the processing. In particular, since wiring accuracy can be improved, high-density wiring can be performed. In addition, the strength of the disk-shaped glass is improved, and the disk-shaped glass and the laminated body are not easily damaged. In addition, the number of times of reuse (the number of times of support) of the disk-shaped glass can be increased. Here, the "arithmetic mean roughness Ra" can be measured by an atomic force microscope (AFM).

In the disk-shaped glasses G3 and G4, the average thermal expansion coefficient in the temperature range of 30 to 380°C is preferably 0×10 ^-7 /°C or higher and 165×10 ^-7 /°C or lower. Thereby, the thermal expansion coefficients of the processed substrate and the disk-shaped glass can be easily adjusted. Next, when the thermal expansion coefficients of the two are integrated, dimensional changes (especially warpage deformation) of the processed substrate can be easily suppressed during processing. As a result, high-density wiring can be performed on one of the surfaces of the processed substrate, and solder bumps can be accurately formed. Among them, the "average thermal expansion coefficient in the temperature range of 30 to 380°C" can be measured by a thermal dilatometer.

The average thermal expansion coefficient in the temperature range of 30 to 380°C is preferably increased if the proportion of semiconductor wafers is small and the proportion of sealing materials is large in the processed substrate. When the ratio of the wafer is large and the ratio of the sealing material is small, it is preferable to reduce it.

When the average thermal expansion coefficient in the temperature range of 30 to 380°C of the disc glasses G3 and G4 is 0×10 ^-7 /°C or more, and less than 50×10 ^-7 /°C, the disc glass is more Preferably, it contains 55~75% of _SiO2 , 15~30% of _Al2O3 , 0.1~6% of _Li2O , ₀ ~ ₈ % of Na2O ₊ K2O, MgO+CaO+SrO+ in mass % BaO 0~10%, as a glass composition, or preferably 55~75% SiO ₂ , 10~30% Al ₂ O ₃ , Li ₂ O+Na ₂ O+K ₂ O 0~0.3%, MgO+ CaO+SrO+BaO 5~20%. When the average thermal expansion coefficient in the temperature range of 30 to 380°C is 50×10 ^-7 /°C or more and less than 75×10 ^-7 /°C, the disc-shaped glass preferably contains, in mass %, SiO ₂ 55~70%, Al ₂ O ₃ 3~15%, B ₂ O ₃ 5~20%, MgO 0~5%, CaO 0~10%, SrO 0~5%, BaO 0~5%, ZnO 0~5%, Na ₂ O 5~15%, K ₂ O 0~10%, as glass composition. When the average thermal expansion coefficient in the temperature range of 30 to 380°C is 75×10 ^-7 /°C or more and 85×10 ^-7 /°C or less, the disc glass preferably contains SiO in mass %. ₂ 60~75%, Al ₂ O ₃ 5~15%, B ₂ O ₃ 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%, as glass composition. When the average thermal expansion coefficient in the temperature range of 30 to 380°C is more than 85×10 ^-7 /°C and 120×10 ^-7 /°C or less, the disc glass preferably contains SiO in mass %. ₂ 55~70%, Al ₂ O ₃ 3~13%, B ₂ O ₃ 2~8%, MgO 0~5%, CaO 0~10%, SrO 0~5%, BaO 0~5%, ZnO 0 ~5%, Na ₂ O 10~21%, K ₂ O 0~5%, as glass composition. When the average thermal expansion coefficient in the temperature range of 30 to 380°C is more than 120 × 10 ^-7 /°C and 165 × 10 ^-7 /°C or less, the disc-shaped glass preferably contains SiO in mass %. ₂ 53~65%, Al ₂ O ₃ 3~13%, B ₂ O ₃ 0~5%, MgO 0.1~6%, CaO 0~10%, SrO 0~5%, BaO 0~5%, ZnO 0 ~5%, Na ₂ O+K ₂ O 20~40%, Na ₂ O 12~21%, K ₂ O 7~21%, as glass composition. As described above, it is easy to regulate the thermal expansion coefficient within a desired range, and the devitrification resistance is improved, so that it is easy to form a disk-shaped glass with a small variation in the overall plate thickness.

The strain points of the disk-shaped glasses G3 and G4 are preferably 480°C or higher, 500°C or higher, 510°C or higher, 520°C or higher, particularly 530°C or higher. The higher the strain point, the easier it is to reduce thermal shrinkage. Here, "strain point" means the value measured by the method of ASTM C336.

The Young's modulus of the disc glass G3 and G4 is preferably 65GPa or more, 67GPa or more, 68GPa or more, 69GPa or more, 70GPa or more, 71GPa or more, 72GPa or more, especially 73GPa or more. If the Young's modulus is too low, it is difficult to maintain the rigidity of the laminate, and deformation, warpage, and breakage of the processed substrate are likely to occur.

The liquidus temperature of the disc glass G3 and G4 is preferably not more than 1150°C, 1120°C or lower, 1100°C or lower, 1080°C or lower, 1050°C or lower, 1010°C or lower, 980°C or lower, 960°C or lower, and 950°C or lower. , especially below 940℃. As described above, it is easy to form the disc-shaped glass by the down-draw method, especially the overflow down-draw method, so that the disc-shaped glass with a small plate thickness can be easily produced, and the variation in plate thickness after forming can be reduced. Moreover, at the time of the manufacturing process of the disc-shaped glass, it is easy to prevent a situation in which devitrification crystallisation occurs and the productivity of the disc-shaped glass falls. Here, the "liquidus temperature" can pass through a standard sieve with 30 meshes (500 μm), put the glass powder remaining in 50 meshes (300 μm) into a platinum boat, and keep it in a temperature gradient furnace for 24 hours. Calculated by measuring the temperature at which crystals are precipitated.

The viscosity in the liquidus temperature of the disc glass G3 and G4 is preferably 10 ^4.6 dPa·s or more, 10 ^5.0 dPa·s or more, 10 ^5.2 dPa·s or more, 10 ^5.4 dPa·s or more, 10 ^5.6 dPa·s or more or more, especially 10 ^5.8 dPa·s or more. As described above, it is easy to form the disc-shaped glass by the down-draw method, especially the overflow down-draw method, so that the disc-shaped glass with a small plate thickness can be easily produced, and the variation in plate thickness after forming can be reduced. Moreover, it is easy to prevent a situation in which devitrification crystallization occurs and the productivity of the disc-shaped glass falls during the manufacturing process of the disc-shaped glass. Here, the "viscosity at liquidus temperature" can be measured by the platinum ball pull-up method. Among them, the viscosity in the liquidus temperature is an index of the formability, and the higher the viscosity in the liquidus temperature, the better the formability.

The temperature at 10 ^2.5 dPa·s of the disc glass G3 and G4 is preferably 1580°C or lower, 1500°C or lower, 1450°C or lower, 1400°C or lower, 1350°C or lower, especially 1200 to 1300°C. When the temperature in 10 ^2.5 dPa·s becomes high, the meltability decreases, and the manufacturing cost of the disk-shaped glass increases. Here, the "temperature in 10 ^2.5 dPa·s" can be measured by the platinum ball pull-up method. Among them, the temperature in 10 ^2.5 dPa·s corresponds to the melting temperature, and the lower the temperature, the better the meltability.

The difference between the stress at the center of the main surface of the disk-shaped glass G3 and G4-based glass and the stress at the edge is 0 to 10 MPa. The end part here refers to any part 100mm away from the end face. With the stress characteristics shown above, it is considered that the entire substrate is warped in the shape of a bowl, a saddle, or a valley. The above-mentioned shape is less likely to cause the inconvenience of the semiconductor wafer on the substrate falling off during production than a locally warped substrate, and can be manufactured with high productivity. (When used as a semiconductor support substrate, it is not easily deformed in the semiconductor manufacturing process, and semiconductors can be manufactured with high productivity. The internal stress is relieved by the above-mentioned heat treatment process S2, so the stress of the disk-shaped glasses G3 and G4 is considered to be within the range described above).

The disk-shaped glass G3 and G4 are plate-like in visual observation, but when viewed in an enlarged view, they have minute warpages or uneven shapes of an extent that is acceptable at the time of use. For example, the disk-shaped glasses G3 and G4 are formed in the shapes of bowls, saddles, and valleys as shown in FIGS. 9A and 9B to FIGS. 11A and 11B . FIGS. 9A and 9B to FIGS. 11A and 11B are diagrams showing an example of the shape of the disc-shaped glass of the present embodiment measured by SBW-331ML/d manufactured by KOBELCO Scientific Co., Ltd. in the thickness direction, respectively. FIGS. 9A , 10A and 11A show the high and low shapes of the disk-shaped glasses G3 and G4 in a plan view in shades, and the darker the darker, the lower the position. 9B, 10B, and 11B show the three-dimensional oblique shapes of the disk-shaped glasses G3 and G4.

9A and 9B show disk-shaped glasses G3 and G4 formed into a bowl shape. The bowl shape refers to a shape in which the central portion is more concave than the outer peripheral portion. In particular, when the radius of the disk-shaped glasses G3 and G4 is r (mm), it is preferable to form a bowl shape in a region within 0.8r from the center. When the disc-shaped glasses G3 and G4 have a bowl shape and are used for a semiconductor support substrate, it is preferable to support the semiconductor substrate on the concave side among the main surfaces. As described above, the semiconductor substrate can be stably supported. In this case, in order to clarify which side of the main surfaces of the disk-shaped glasses G3 and G4 should be used as the support surface, it is preferable to form identification marks such as engravings or stickers on the main surfaces on the side of the depressions.

FIGS. 10A and 10B show disk-shaped glasses G3 and G4 formed in a saddle shape. The saddle shape refers to a shape that is partially warped in a first direction along the plate thickness direction, and partially warped in a second direction opposite to the first direction. In FIGS. 10A and 10B , the disk-shaped glasses G3 and G4 show shapes that are warped in different directions around each of two axes that run substantially straight at the center. When the disk-shaped glasses G3 and G4 are saddle-shaped, it is considered that the internal stress balance has been achieved, and deformation and the like during use can be suppressed.

FIGS. 11A and 11B show disk-shaped glasses G3 and G4 formed in a valley shape. The valley shape refers to a shape that is warped only in one direction of the plate thickness direction.

Among them, the use of the disk-shaped glass G3 and G4 is not limited to the semiconductor support use, and can be diverted to any use.

Claims (13)

A method for manufacturing disc-shaped glass, which is characterized by comprising: a heat treatment process in which a glass plate is heated from room temperature to a temperature range of -50°C to cool point +80°C in advance. Cooling is performed after the set peak temperature; a circular cutting process is to cut a disk-shaped glass from the glass plate; A method for producing a disc-shaped glass, which is used for a method for producing a disc-shaped glass supporting a processing substrate, characterized by comprising: a heat treatment process in which a glass plate having a Young's modulus of 65 GPa or more is prepared; After heating from room temperature to a pre-set wave peak temperature in the range of the cold point -50°C to the cold point +80°C, it is cooled; the circular cutting process is to cut a disk shape from the aforementioned glass plate glass; and a notch forming process for forming a notch at the end of the disk-shaped glass plate. Manufacture of disc-shaped glass as claimed in item 1 or item 2 of the scope of the patent application The method, wherein, the aforementioned heat treatment process comprises: a heating step, which is heated from room temperature to the aforementioned peak temperature at a speed of +1~+16°C/min; a holding step, which is after the aforementioned heating step, at the aforementioned peak temperature A holding temperature in the range of -10°C to the aforementioned peak temperature is maintained for 0 to 120 minutes; and a cooling step, which is performed after the aforementioned holding step, in a temperature range from the aforementioned holding temperature to the strain point of the aforementioned glass plate -50°C , cool down at a rate of -6.0~-0.3℃/min. The method for producing a disc-shaped glass of claim 3, wherein the cooling step comprises: a first cooling step, which is in a temperature range from the holding temperature to the strain point of the glass plate -50°C , cooling at a rate of -3.0~-0.3°C/min; and a second cooling step, which is in the temperature region below the strain point -50°C, cooling at a rate of -5.8~-1.1°C/min. The method for producing a disk-shaped glass according to claim 1 or claim 2, wherein, in the heat treatment process, the heat treatment is performed in a state where a load is applied to the glass plate in the thickness direction. The method for producing a disk-shaped glass according to claim 5, wherein a plurality of the glass plates are laminated with a release material interposed therebetween, The aforementioned heat treatment of the aforementioned heat treatment process is performed in a state where the pressing member is placed on the uppermost stage. The method for producing a disk-shaped glass according to claim 6, wherein a supporting member is additionally arranged at the lowermost stage of the plurality of the glass plates, so that the contact surface of each of the pressing member and the supporting member with the glass plate, larger than the major surface of the aforementioned glass sheet. The method for producing disk-shaped glass according to claim 1 or claim 2, further comprising a grinding step, which is performed after the aforementioned heat treatment step and before or after the aforementioned circular cutting step. , the two main surfaces of the glass plate are ground, and in the above-mentioned grinding, the grinding amount of the other main surface is within the range of 0.8 to 1.2 times the grinding amount of the one main surface. The method for producing a disk-shaped glass according to claim 1, wherein the circular cutting process is performed after the heat treatment process, and the notch forming process is provided after the circular cutting process. Disk-shaped glass having a warpage of 200 μm or less, a difference between the stress at the center of the main surface and the stress of the main surface at a position 100 mm from an end surface of 0 to 10 MPa, and having a notch at the end. The disk-shaped glass according to claim 10, wherein, if the radius is set to r (mm), a bowl shape is formed in a region within 0.8r from the center. The disc-shaped glass according to claim 11, wherein the main surface which becomes the upper surface in use has an identification mark, and has the bowl shape in which the depression is formed on the main surface side where the identification mark is formed. The disk-shaped glass according to claim 10, wherein a saddle shape is formed.

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