JP6893691B2 - Method and system for manufacturing multi-layer brittle material substrate - Google Patents

Description

The present invention relates to the production of a brittle material substrate in which a plurality of plate-shaped brittle materials are laminated, and in particular, the thickness of the brittle material forming the lowermost portion and the uppermost portion is larger than the thickness of the brittle material forming the intermediate portion. The present invention relates to the production of a small multi-layer brittle material substrate.

As a multi-layer substrate having a structure in which a plurality of plate-shaped brittle material substrates (for example, glass substrates) are bonded and laminated, a so-called bonded substrate in which two upper and lower brittle material substrates are bonded is already widely known. .. An example is a liquid crystal display configured by enclosing a liquid crystal between the upper and lower brittle material substrates. Further, a laminated ceramic substrate in which a plurality of ceramic substrates are laminated is also known (see, for example, Patent Document 1).

In addition, as a technique for dividing a prefabricated mother substrate into individual bonded substrates in order to obtain a bonded substrate of a desired size, a tool such as a cutter wheel or a diamond cutter is used to surface the mother substrate. It is already known that a scribe line is formed on each of the back surfaces and the scribe line is divided by crack extension from the scribe line (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-0838808

There is a certain need to use a multi-layer substrate in which three or more plate-shaped brittle materials are bonded and laminated. From the viewpoint of industrial mass production, it is preferable to obtain the multi-layer substrate by dividing the mother substrate, but as disclosed in Patent Document 1, crack extension from a scribe line formed on the front and back surfaces of the mother substrate. Although it is possible to divide the uppermost substrate and the lowermost substrate by the method of dividing by, cracks may not easily extend to the intermediate substrate sandwiched between the two.

Further, methods such as drilling and dicing have problems that carfloss occurs, dry processing cannot be performed, and a large amount of brittle material powder is generated.

On the other hand, it is also conceivable to perform division by laser processing, which is a non-contact processing method. However, _{the method of forming a scribe line with a CO 2} laser and extending the cracks cannot be adopted because the cracks do not extend on the substrate in the intermediate portion as in the case of using the tool.

On the other hand, although it is possible to divide by the ablation processing method that causes evaporation in the irradiated portion of the laser beam, there is a problem that the edge strength of the obtained brittle material substrate tends to decrease due to the influence of heat. is there.

Alternatively, it is conceivable to modify the irradiated portion by locally causing melting in the irradiated portion of the laser beam and realize the division at the subsequent break, but chipping occurs at the edge portion at the break. I have something to do.

Further, among the mother substrates for obtaining a multi-layer substrate in which three or more plate-shaped brittle materials are adhered and laminated, the thickness of the brittle materials located at the uppermost portion and the lowermost portion is located in the middle portion. For materials smaller than the thickness of the brittle material, it is not always easy to obtain the material itself due to the difficulty of bonding and alignment due to the occurrence of bending.

The present invention has been made in view of the above problems, and is a method capable of suitably producing a multi-layer brittle material substrate in which the thickness of the brittle material constituting the lowermost portion and the uppermost portion is smaller than the thickness of the brittle material constituting the intermediate portion. The purpose is to provide.

In order to solve the above problems, in the method for producing a multi-layer brittle material substrate of the present invention, plate-shaped brittle materials are laminated, and the thickness of the brittle material forming the lowermost portion and the uppermost portion constitutes an intermediate portion. A method for producing a multi-layer brittle material substrate smaller than the thickness of the brittle material, a) with the brittle material constituting the lowermost portion, the uppermost portion, and the intermediate portion of the multi-layer brittle material substrate, respectively. A bottom portion made of the same brittle material and having a thickness larger than the target thickness of the lowermost portion of the multi-layer brittle material substrate, and a top portion having a thickness larger than the target thickness of the uppermost portion of the multi-layer brittle material substrate. , A step of preparing a mother substrate having an intermediate portion having the same thickness as the target thickness of the intermediate portion of the intermediate portion of the multi-layer brittle material substrate and having a plane size larger than that of the multi-layer brittle material substrate, and b) the mother. A step of forming a modified region that crosses at least the intermediate portion and projects to the lowermost portion and the uppermost portion at a predetermined planned division position of the mother substrate by irradiating the substrate with laser light, and c. ) The mother substrate that has undergone the step b) is provided so that the thicknesses of the lowermost portion and the uppermost portion of the mother substrate are equal to the target thicknesses of the lowermost portion and the uppermost portion of the multi-layer brittle material substrate, respectively. It is characterized by including a step of etching and a step of dividing the mother substrate that has undergone d) the step c) along the modified region remaining in the intermediate portion.

The thickness of the lowermost portion and the uppermost portion of the mother substrate prepared in the step a) can be equal to the thickness of the intermediate portion.

The step c) can be performed by chemical etching.

The plate-shaped brittle material can be a glass material.

In the system for producing a multi-layer brittle material substrate of the present invention, plate-shaped brittle materials are laminated, and the thickness of the brittle material forming the lowermost portion and the uppermost portion is larger than the thickness of the brittle material forming the intermediate portion. A system for producing a small multi-layer brittle material substrate, each of which is composed of the same brittle material as the brittle material constituting the lowermost portion, the uppermost portion, and the intermediate portion of the multi-layer brittle material substrate. In addition, the bottom portion having a thickness larger than the target thickness of the lowermost portion of the multi-layer brittle material substrate, the uppermost portion having a thickness larger than the target thickness of the uppermost portion of the multi-layer brittle material substrate, and the multi-layer brittle material substrate. By irradiating a mother substrate having an intermediate portion having the same thickness as the target thickness of the intermediate portion of the above and having a plane size larger than that of the multi-layer brittle material substrate, the mother substrate is predetermined. The mother substrate is provided with a laser beam irradiation means for forming a modified region that crosses at least the intermediate portion and projects to the lowermost portion and the uppermost portion at a planned division position, and the mother substrate on which the modified region is formed. The etching means for etching and the etched mother substrate so that the thicknesses of the lowermost portion and the uppermost portion of the substrate are equal to the target thicknesses of the lowermost portion and the uppermost portion of the multi-layer brittle material substrate, respectively. It is characterized by comprising a dividing means for dividing along the modified region remaining in the intermediate portion.

According to the present invention, it is possible to preferably obtain a multi-layer brittle material substrate in which the thickness of the brittle material at the bottom and the top is smaller than the thickness of the brittle material at the middle without causing chipping at the end. it can.

It is a figure which shows typically the structure of the multi-layer brittle material substrate 10. It is a figure which shows the procedure which obtains the multi-layer brittle material substrate 10 from the mother substrate 10M. It is a perspective view of the mother substrate 10M used for manufacturing the multi-layer brittle material substrate 10. It is a perspective view which shows the state of irradiating the laser light LB with respect to the planned division position P perpendicular to the x-axis in the mother substrate 10M. FIG. 5 is a zx cross-sectional view of a mother substrate 10M showing a modified region RE1 formed by irradiation with laser light LB. It is a zx cross-sectional view of the mother substrate 10M for demonstrating the etching process. It is a zx cross-sectional view of the mother substrate 10M after the etching process. It is a figure which shows typically the divided piece 10α.

Hereinafter, the method and system according to the present embodiment will be described for the case of obtaining the multi-layer brittle material “substrate”, but the multi-layer brittle material substrate obtained by the method and system according to the present embodiment will be described. , Not necessarily limited to those used as a general "board".

FIG. 1 is a diagram schematically showing the configuration of a multi-layer brittle material substrate 10 obtained by applying the method and system according to the present embodiment. The multi-layer brittle material substrate 10 is a multi-layer substrate having a rectangular shape in a plan view, which is formed by adhering and laminating three plate-shaped brittle materials. The brittle material is, for example, a glass material, but the three brittle materials do not have to be the same material.

More specifically, the multi-layer brittle material substrate 10 has two main surfaces (front and back surfaces) of an intermediate portion 1 having a predetermined thickness (target thickness) t1 and a bottom 2 and a thickness (target thickness) t2, respectively. Target thickness) It has a structure in which the uppermost portion 3 of t3 is adhered. However, preferably, at least the lowermost portion 2 and the uppermost portion 3 are made of the same substance, and t2≈t3 <t1. For example, t1 is about several hundred μm to several mm, and t2 and t3 are about several tens of μm to several hundred μm. Alternatively, the intermediate portion 1 may be made of the same material.

The lowermost portion 2 is adhered to the intermediate portion 1 by the adhesive layer A1, and the uppermost portion 3 is adhered to the intermediate portion 1 by the adhesive layer A2, but the thicknesses of the adhesive layers A1 and A2 are larger than those of t2 and t3. It is sufficiently small, and is about several μm to several tens of μm. In addition, although it may be in a mode in which another substance such as a liquid crystal is sealed between the lowermost portion 2 and the intermediate portion 1 and at least one between the uppermost portion 3 and the intermediate portion 1, the present embodiment may be performed. In the form, for convenience, it is assumed that the adhesive layers A1 and A2 are adhered to each other including such cases.

On the other hand, the plane size of the multi-layer brittle material substrate 10 varies depending on the purpose of use thereof, and appropriate dimensions are selected in the range of several cm to several m.

FIG. 2 is a diagram showing a procedure for obtaining a multi-layer brittle material substrate 10 from a mother substrate (multi-layer mother substrate) 10M, which is carried out by using the method and system according to the present embodiment. As shown in FIG. 2, in separating the multilayer brittle material substrate 10 from the mother substrate 10M, first, the mother substrate 10M is prepared (step S1). FIG. 3 is a perspective view of the mother substrate 10M used for producing the multi-layer brittle material substrate 10.

Like the multi-layer brittle material substrate 10, the mother substrate 10M is a multi-layer substrate having a rectangular shape in a plan view, which is formed by adhering and laminating three plate-shaped brittle materials, but its planar size is brittle. It is sufficiently large compared to the material substrate. In FIG. 3, the xyz coordinates of the right handprint are attached, with the extending directions of the two sides when the mother substrate 10M is viewed in a plan view as the x-axis and the y-axis, respectively, and the stacking direction as the z-axis (). The same applies to FIG. 4).

Further, the mother substrate 10M has a configuration in which the lowermost portion 2M and the uppermost portion 3M are adhered to the two main surfaces (front and back surfaces) of the intermediate portion 1M, respectively, like the multilayer brittle material substrate 10. The materials of the intermediate portion 1M, the lowermost portion 2M, and the uppermost portion 3M are the same as those of the intermediate portion 1, the lowermost portion 2, and the uppermost portion 3 of the multi-layer brittle material substrate 10, respectively.

However, the thickness T1 of the intermediate portion 1M is the same as the thickness t1 of the intermediate portion 1 of the multi-layer brittle material substrate 10, whereas the thickness T2 of the lowermost portion 2M is the thickness t2 of the lowermost portion 2 of the multilayer brittle material substrate 10. The thickness T3 of the uppermost portion 3M is larger than the thickness t3 of the uppermost portion 3 of the multi-layer brittle material substrate 10. That is, the thicknesses T1 to T3 are all about several hundred μm to several mm. Preferably, T2 = T3, but T2 = T3 = T1 may be further obtained. That is, the three portions may have the same thickness.

Further, the adhesive layer A1M that adheres the lowermost portion 2M and the intermediate portion 1M and the adhesive layer A2M that adheres the uppermost portion 3M and the intermediate portion 1M are each when the multi-layer brittle material substrate 10 is finally obtained. It is a layer to be the adhesive layers A1 and A2.

With respect to the mother substrate 10M having such a configuration, planned division positions P (P1, P2) are set in advance at predetermined pitches pa and pb in each of the x-axis direction and the y-axis direction. In FIG. 3, the planned division position P is indicated by a alternate long and short dash line crossing the upper surface of the uppermost portion 3M. More specifically, the planned division position P passes through the alternate long and short dash line and is in the z-axis direction. It is a surface along. Then, the area partitioned by all four scheduled division positions P, that is, two adjacent planned division positions P (P1) in the x-axis direction and two adjacent planned division positions P (P2) in the y-axis direction, is formed. Finally, it will be separated from the mother substrate 10M as one multi-layer brittle material substrate 10. In other words, the pitches pa and pb generally correspond to the plane sizes of the multi-layer brittle material substrate 10 finally obtained through the division at the four planned division positions P in the directions orthogonal to each other.

However, in FIG. 3, two planned division positions P (P1, P2) are shown in the x-axis direction and the y-axis direction, respectively, but this is for convenience of illustration only. In practice, it is planned to obtain a large number of multi-layer brittle material substrates 10 from one mother substrate 10M by setting a large number of planned division positions P for the mother substrate 10M having a sufficiently large planar size. To.

When the mother substrate 10M is prepared, the laser beam LB is irradiated to the mother substrate 10M, so that at least a portion of the planned division position P located inside the mother substrate 10M is (more specifically, the portion). The region including the vicinity of is modified (step S2). FIG. 4 is a perspective view showing a state in which the laser beam LB is irradiated to the planned division position P (P1) perpendicular to the x-axis on the mother substrate 10M. Further, FIG. 5 is a zx cross-sectional view of the mother substrate 10M showing the modified region RE1 formed by irradiation with the laser beam LB. However, in FIG. 5, for convenience, the planned division position P is shown as a alternate long and short dash line extending to the outside of the mother substrate 10M (the same applies to FIGS. 6 and 7).

As shown in FIG. 4, when the mother substrate 10M is in a posture in which the upper surface of the uppermost portion 3M is perpendicular to the z-axis direction as in FIG. 3, the laser beam LB is scheduled to be divided from the vertically upper side of the uppermost portion 3M. It is irradiated toward the position P (that is, in the negative direction of the z-axis) and scanned along the planned division position P (in the negative direction of the y-axis in the case shown in FIG. 4) as shown by the arrow AR1. Will be done.

However, as shown in FIG. 5, the laser beam LB is irradiated under the condition that the modified region RE1 is formed from the lowermost portion 2M to the uppermost portion 3M. That is, the modified region RE1 has a predetermined width w including the planned division position P, and at least the portion crossing the intermediate portion 1M and the z-axis negative direction from the crossing portion to the lowermost 2M. It is formed so as to have a portion protruding in the z-axis direction with respect to the uppermost portion 3M. More specifically, the modified region RE1 has d2 ≧ t2, with respect to the height (depth) d2 of the protruding portion to the lowermost portion 2M and the height (depth) d3 of the protruding portion to the uppermost portion 3M. It is formed so that d3 ≧ t3 is satisfied. Preferably, it is formed so that d2 = t2 (d2≈t2) and d3 = t3 (d3≈t3).

As the laser light LB, various lasers such as a visible light laser and an IR laser can be used. Specific laser light LB irradiation conditions (for example, laser wavelength, energy, beam spot diameter, focal position, scanning speed, etc.) are determined in consideration of the material and thickness of each part of the mother substrate 10M and the multi-layer brittle material substrate 10. It may be determined as appropriate. Depending on the thickness of the mother substrate 10M, a plurality of irradiations at different focal positions may be performed.

Further, the modified region RE1 may be formed so as to cross not only the intermediate portion 1M but also the lowermost portion 2M and the uppermost portion 3M (that is, d2≈T2, d3≈T3), but ablation occurs. It is necessary not to.

The mother substrate 10M on which the modified region RE1 is formed as described above is subsequently subjected to an etching treatment.

FIG. 6 is a zx cross-sectional view of the mother substrate 10M for explaining the etching process. FIG. 7 is a zx cross-sectional view of the mother substrate 10M after the etching treatment.

The etching is performed for the purpose of removing a part of the lowermost portion 2M and the uppermost portion 3M as shown by arrows AR2 and AR3 in FIG. Specifically, the surfaces of the bottom 2M and the top 3M reach at least the end positions of the modified region RE1 in the bottom 2M and the top 3M shown by the broken line in FIG. 6 after etching. It is performed (step S3).

As a specific etching method, it is preferable to adopt chemical etching. The specific components of the etching agent and the etching conditions may be appropriately selected in consideration of the material, thickness, and the like of each part of the mother substrate 10M and the multi-layer brittle material substrate 10.

Strictly speaking, in the etching, the thickness of the lowermost portion 2M after etching is the same as the thickness t2 of the lowermost portion 2 of the multi-layer brittle material substrate 10, and the thickness of the uppermost portion 3M is the thickness of the uppermost portion 3 of the multi-layer brittle material substrate 10. It needs to be done so as to be the same as the thickness t3 of. Therefore, in the case of d2> t2 and d3> t3, even after the surfaces of the lowermost portion 2M and the uppermost portion 3M reach the above-mentioned end positions, etching is further performed to positions corresponding to the thicknesses t2 and t3. It is said.

In other words, the etching depth e2 from the lowermost 2M surface (back surface of the mother substrate 10M) and the etching depth e3 from the uppermost 3M surface (front surface of the mother substrate 10M) are e2 = T2-t2, respectively. , E3 = T3-t3.

Actually, when the etching treatment is performed in the above manner, as shown in FIG. 7, the portion of the modified region RE1 that protrudes to the lowermost portion 2M and the uppermost portion 3M disappears, and the portion concerned disappears. Grooves G2 and G3 are formed in the existing portions, respectively. Then, the modified region RE2 remains only in the intermediate portion 1M. This is because the material strength of the modified region RE1 is weaker than the material strength of the lowermost 2M and the uppermost 3M of the surroundings, and therefore the etching rate is higher than that of the surroundings. Conceivable. In FIG. 7, for convenience of illustration, the edge portion formed by the groove portions G2 and G3 and the surface of the mother substrate 10M is shown to be angular, but the portion is microscopically curved. .. So to speak, it is in a chamfered state. Further, in FIG. 7, the modified region RE2 exists in a manner crossing the intermediate portion 1M, but the groove portions G2 and G3 may be formed so as to enter the modified region RE2.

When the etching process is completed, the mother substrate 10M is divided along the modified region RE2. In the case shown in FIG. 7, the mother substrate 10M is divided into two portions 10A and 10B facing each other with the modified region RE2 in between (step S4).

This is achieved by applying stresses in opposite directions to the two portions 10A and 10B, as shown by arrows AR4. Since the material strength of the modified region RE2 is weaker than the material strength of the surrounding intermediate portion 1M, the application of such stress makes it easy for the two portions 10A and 10B to each other at the modified region RE2. Be separated. As a result, the two portions 10A and 10B are separated with good quality. The stress may be applied by pulling the portions 10A and 10B in opposite directions in the horizontal plane, or by applying a so-called three-point bending method.

In such a case, only the modified region RE2 existing in a manner crossing the intermediate portion 1M is actually targeted for separation. The bottom 2M and top 3M of portions 10A and 10B are already separated from each other. Therefore, chipping does not occur at the bottom 2M and the top 3M during separation.

FIG. 8 shows the divided pieces 10α obtained by performing the division / separation at the modified region formed at each of the four planned division positions P (P1, P2) shown in FIG. It is a figure which shows typically. More specifically, in the divided piece 10α after the division, the substance existing in the modified region RE1 remains on the end face F, but the substance is removed by an appropriate cleaning treatment or the like.

The divided piece 10α has a configuration in which a lowermost portion 2α having a thickness t2 and an uppermost portion 3α having a thickness t3 are adhered to two main surfaces (front and back surfaces) of an intermediate portion 1α having a thickness t1. That is, the divided piece 10α has the same structure as the multilayer brittle material substrate 10 shown in FIG. 1 in the thickness direction. Therefore, if the pitch of the planned division position P is made to match the plane size of the multi-layer brittle material substrate 10 as described above, the multi-layer brittle material substrate 10 can be obtained by the procedure shown in FIG. Become.

Strictly speaking, the shape of the end face F is slightly different from the shape of the end of the multi-layer brittle material substrate 10 shown in FIG. 1, but the edge portion of the divided piece 10α is etched as described above. Since it is in a chamfered state at the time of etching, it has a rather preferable shape in terms of ensuring end face strength.

Further, the formation of the modified region RE1 is indispensable when producing the divided piece 10α, but by determining the pitch size of the planned division position P in anticipation of this, the plane size of the divided piece 10α can be a desired multiple. It is possible to match the plane size of the layer brittle material substrate 10.

As described above, according to the present embodiment, it is a multi-layer brittle material substrate formed by adhering and laminating three plate-shaped brittle materials, and is a bottom and top brittle material. A multi-layer brittle material substrate having a thickness smaller than the thickness of the brittle material in the intermediate portion can be suitably obtained without causing chipping at the end portion.

It should be noted that the mother substrate 10M obtained by preliminarily setting the thicknesses of the brittle material forming the lowermost portion 2M and the uppermost portion 3M to the brittle material forming the middle portion 1M is considered to be the target of division. However, in general, the larger the plane size and the smaller the thickness of the brittle material, the more difficult it is to bond due to its bending. Further, even if the bonding is performed in such a mode and the division is subsequently performed at the planned division position, it is difficult to chamfer the end portion thereof. It can be said that the methods and systems described above are excellent in that they can be easily performed.

<Modification example>
In the above-described embodiment, the number of plate-shaped brittle materials forming the intermediate portion is one, but the method of the above-described embodiment can be applied even if there are a plurality of brittle materials forming the intermediate portion. Is. In such a case, when preparing the mother substrate, for example, the thickness of the brittle material forming the lowermost portion and the uppermost portion may be the same as the thickness of one brittle material forming the intermediate portion.

1 Intermediate part (of multi-layer brittle material substrate) 1M Intermediate part (of mother substrate) 2M Bottom part (of multi-layer brittle material substrate) 2M Bottom part (of mother substrate) 3 (Top part 3M of multi-layer brittle material substrate) Top 10 (of mother substrate) Multi-layer brittle material substrate 10α Divided piece 10M Mother substrate A1, A2 Adhesive layer A1M, A2M (of mother substrate) Adhesive layer F End face G2, G3 Groove LB Laser light P (P1, P2) Scheduled division position RE1, RE2 Modified region

Claims (2)

A method for producing a multi-layer brittle material substrate in which plate-shaped brittle materials are laminated and the thickness of the brittle material forming the lowermost portion and the uppermost portion is smaller than the thickness of the brittle material forming the intermediate portion. ,
a) The target thickness of the lowermost part of the multi-layered brittle material substrate, each of which is made of the same brittle material as the brittle material constituting the lowermost part, the uppermost part, and the intermediate part of the multi-layered brittle material substrate. A bottom portion having a thickness larger than that of the multi-layer brittle material substrate, an uppermost portion having a thickness larger than the target thickness of the uppermost portion of the multi-layer brittle material substrate, and an intermediate portion having the same thickness as the target thickness of the intermediate portion of the multi-layer brittle material substrate. A step of preparing a mother substrate having a larger plane size than the multi-layer brittle material substrate.
b) By irradiating the mother substrate with a laser beam, a modified region is formed at a predetermined planned division position of the mother substrate so as to cross at least the intermediate portion and project to the lowermost portion and the uppermost portion. Process and
c) In the mother substrate that has undergone the step b), the thicknesses of the lowermost portion and the uppermost portion of the mother substrate are equal to the target thicknesses of the lowermost portion and the uppermost portion of the multi-layer brittle material substrate, respectively. , Etching process and
d) A step of dividing the mother substrate that has undergone the step c) along the modified region remaining in the intermediate portion, and a step of dividing the mother substrate.
A method for producing a multi-layer brittle material substrate. A system for producing a multi-layer brittle material substrate in which plate-shaped brittle materials are laminated and the thickness of the brittle material forming the lowermost portion and the uppermost portion is smaller than the thickness of the brittle material forming the intermediate portion. There,
a) Aimed thickness of the bottom of the multi-layer brittle material substrate, each of which is made of the same brittle material as the brittle material constituting the bottom, top, and intermediate of the multi-layer brittle material substrate. A bottom portion having a thickness larger than that of the multi-layer brittle material substrate, an uppermost portion having a thickness larger than the target thickness of the uppermost portion of the multi-layer brittle material substrate, and an intermediate portion having the same thickness as the target thickness of the intermediate portion of the multi-layer brittle material substrate. By irradiating the mother substrate, which has and has a larger plane size than the multi-layer brittle material substrate, with laser light, at least the intermediate portion is crossed at a predetermined predetermined division position of the mother substrate. A laser beam irradiating means for forming a modified region protruding from the lowermost portion and the uppermost portion, and
The thickness of the lowermost portion and the uppermost portion of the mother substrate on which the modified region is formed is equal to the target thickness of the lowermost portion and the uppermost portion of the multi-layer brittle material substrate, respectively. Etching means to etch,
A dividing means for dividing the etched mother substrate along the modified region remaining in the intermediate portion, and
A system for producing a multi-layer brittle material substrate.

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