JP2001293586A - Method of cutting glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of cutting glass, by which the generation of a chipping, a microcrack, or cullet is prevented, deterioration of the strength is prevented, and the yield is enhanced, when a lot of small, chip-formed glass pieces are cut out from a glass plate. SOLUTION: The method of cutting glass is composed of a process where a first primary crack 15 which is a start point of cutting is formed with a scriber 3 on one side of the glass plate 1, a first cutting process where the glass plate 1 is cut into a form of a strap by guiding the first primary crack 15 in the direction along a planned cutting line 16 of the glass plate 1 by means of a thermal stress imposed by a laser beam, a process where a second primary crack 24 which is a start point of cutting is formed with the scriber 3 on one side of the glass plate 1a cut into the form of a strap, and a second cutting process where individual chips of small glass pieces 1b is cut out from the glass plate 1a having the form of strap by guiding the second primary crack 24 in the direction along a planned cutting line 25 of the glass plate by means of a thermal stress impressed by laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention divides a single mother glass into a number of chip-shaped glass pieces, and cuts the glass pieces for use as a protective cap for a CCD camera, a line sensor, or the like. About the method.

[0002]

2. Description of the Related Art For example, a single mother glass having a size of 170 mm × 170 mm and a thickness of 0.7 mm is placed in a 10 mm
In a conventional cutting method of dividing into a large number of glass pieces of a chip shape of × 10 mm, the cutting was performed using a dicing saw that cuts mother glass with a rotating diamond cutter.

[0003]

By the way, the above-mentioned cutting by the conventional dicing saw has the following problems.

(1) By rotating a diamond cutter,
Since the mother glass is cut by the rotation force, chipping (breaking, chipping) occurs in the glass, and the yield is deteriorated. This chipping occurs more frequently as the thickness of the glass becomes thinner.

[0005] (2) Cutting with a diamond cutter requires a cutting margin, and this cutting margin becomes cullet (powder glass dust generated during cutting) and adheres to the glass surface. For this reason, many work steps such as chamfering, cullet removing, and washing are required before the glass is cut into a product, which is inefficient and uneconomical.

(3) Microcracks occur on the fractured surface of the glass, and the strength of the glass decreases.

Therefore, an object of the present invention is to provide a glass cutting method which can solve the above-mentioned conventional problems by cutting the glass by using a laser beam method instead of the conventional dicing saw. To provide.

[0008]

In order to solve the above-mentioned problems, the present invention provides a step of forming a first initial crack serving as a processing starting point on one surface of a glass substrate by a scriber; The first initial crack is induced in a direction along the expected cutting line of the glass by the thermal stress applied by the laser beam, and the glass is cut into strips, and the glass is cut into strips. Forming a second initial crack as a processing start point on one surface of the glass by a scriber, and forming the second initial crack in a direction along a scheduled cutting line of the glass by thermal stress applied by a laser beam. The second embodiment employs a configuration in which a second cutting step of guiding and cutting the strip-shaped glass into individual chip-shaped glass pieces is performed.

In the above invention, a method of sucking a glass dust generated at the time of forming a crack by a scriber with a suction nozzle in a step of forming the first and second initial cracks may be adopted, A fall prevention device may be provided to prevent the scriber from falling after the initial crack is formed. In the second breaking step, a pressing means is provided at one end of the glass cut into small pieces. Alternatively, the glass may be pressed.

[0010]

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

FIGS. 1 and 2 show a cleaving device used for carrying out the cleaving method of the present invention. FIG. 10A shows a mother glass 1 to be cleaved by this cleaving device.
A glass chip 1b having a size of 170 mm in width × 170 mm in length and 0.7 mm in thickness, which is formed into a square chip shape having a width of 10 mm × 10 mm in length (FIG. 10)
(C), which is used for a protective cap such as a CCD camera or a line sensor.

As shown in FIGS. 1 and 2, the cleaving device mounts a mother glass 1 on which a rectangular glass 1 is attached.
a (FIG. 10 (B)) and a table 2 for cutting the glass 1a cut into strips, and cutting the glass 1a into chip-shaped glass pieces 1b (FIG. 10 (C)). Table 20 consists of Tables 2 and 20,
It is configured to be movable between the cutting stage K and the standby stage T of the apparatus (in FIG. 1, the table 2 is disposed on the cutting stage K, and the table 20 is disposed on the standby stage T on the right side of the apparatus). FIG. 2 shows a state in which the table 2 is arranged on the standby stage T on the left side of the apparatus and the table 20 is arranged on the cutting stage K).

Table 2 located at the cutting stage K
The scriber 3, the main heat source 4, the sub heat source 5, the main heat source lens 6, the sub heat source lens 7, the moving mirror 8, the fixed mirror 9, and the suction nozzle 10 are arranged above (20). A laser oscillator 11, a guide mirror 12, a control device (not shown), and the like are arranged at appropriate positions below and on the sides.

The table 2 (20) is free to move in the X-axis and Y-axis directions and to rotate around the θ-axis independently of the movement between the cutting stage K and the standby stage T. The distance, order, and the like are appropriately controlled by a control device based on pre-programmed condition settings.

The table 2 has a table 13 for the mother glass 1 and a scriber 3 along one side of the table 13.
Are provided.

On the other hand, the table-shaped glass 1a
Of the scriber 3 is provided along one side of the mounting table 21. Further, the table 20 is provided with a pressing tool 23 which is movable in the longitudinal direction and the vertical direction with respect to the strip-shaped glass 1a placed on the table 20.

As shown in FIGS. 3 and 4, the upper surfaces of the fall prevention devices 14 and 22 are slightly lower than the upper surfaces of the glasses 1 and 1a mounted on the mounting tables 13 and 21, respectively. (Approximately 0.1 mm) so as to prevent the cutting edge of the scriber 3 from falling down when the cutting edge of the scriber 3 comes off the end face of the glass when the initial crack is formed by the scriber 3. This prevents chipping (dust) at the corners of the glass end face.

Further, by forming the side surfaces of the fall prevention members 14, 22 in contact with the glass 1, 1a in an inclined shape to minimize the contact with the glass end surfaces, the generation of dust due to the rubbing of the two can be prevented. I try to prevent it.

The mounting table 21 of the table 20 is shown in FIG.
(C), as shown in FIGS. 8 (D) to (F) and FIG. 9 (G), a predetermined interval (corresponding to the length of one side of the glass piece 1b)
Thus, a comb-shaped projection 21a is provided, and the strip-shaped glass 1a is placed on the projection 21a, so that the cut portion (the portion serving as the glass piece 1b) is supported in a non-contact state.

The pressing member 23 is used when the glass strip 1a is cut into glass chips 1b in the form of chips, and one end portion of the glass which is cut into small pieces (FIG. 7C).
8 (F) to a predetermined pressing force (external stress) set in advance as conditions. Pressing tool 2
Instead of 3, the pressure by air injection may be used.

The scriber 3 is a type of tool that sharpens a hard material such as diamond or cemented carbide and attaches it to the tip of the scriber. (A surface crack line).

The main heat source 4 is a main laser beam, and the sub heat source 5 is a sub laser beam. These heat sources are used when cutting glass.

The output of each of these main and sub laser beams, that is, the power density (the amount of heat per unit area) differs depending on conditions such as the processing speed, size, thickness, material and beam size of the glass. Therefore, the beam output is also input to the control device with a program whose conditions are set in advance.

This processing method uses a local heat source such as a laser beam, and utilizes a thermal stress generated between a central area (compressive stress) and a peripheral area (tensile stress) of the heat source to generate a crack ( This is a processing method that generates and propagates cracks.

The laser oscillator 11 uses, for example, _two CO ₂ lasers having an output of 100 W (a main heat source and a sub heat source).

The sub heat source lens (for example, a plano-convex cylindrical lens having a semi-cylindrical shape) 7 irradiates the beam spot of the sub heat source 5 onto the mother glass 1 (or the strip glass 1a) in an elliptical (elliptical) shape. I do. Also, this lens 7
Is movable in each of the X-axis, Y-axis, and Z-axis (up and down) directions. The movement in the X-axis direction is for enabling the movement to be performed integrally with a later-described moving mirror 8, and the movement in the Y-axis direction is performed by moving the sub- The movement in the Z-axis direction is for adjusting the focal point of the beam spot of the sub heat source 5.

By adjusting the focus of the lens 7, the beam spot of the sub heat source 5 is irradiated onto the glass 1 (1a) in a state where the focus is shifted (defocusing), and the power density of the beam spot is reduced. You can do it.

The main heat source lens (for example, a circular plano-convex lens) 6 irradiates the beam spot of the main heat source 4 onto the glass 1 (1a) in a substantially perfect circular shape.
Is movable in the Z-axis (vertical) direction, and adjusts the focal length of the beam spot of the main heat source 4.

The movement of the sub heat source lens 7 in the X, Y, and Z directions and the movement of the main heat source lens 6 in the Z direction are automatically controlled during operation of the apparatus based on preprogrammed conditions. It has become.

The movable mirror 8 is movable in the X-axis direction.
It moves together with the sub heat source lens 7, and this movement serves to move the beam spot of the sub heat source 5 on the glass 1 (1 a) away from or close to the beam spot of the main heat source 4.

The fixed mirror 9 and the guide mirror 12 reflect the laser beam in the same manner as the movable mirror 8 to reflect the laser beam.
(1a) Play the role of leading up.

The suction nozzle 10 is used when an initial crack is formed on the surface of the glass 1 (1a) by the scriber 3. The suction nozzle 10 removes fine dust slightly generated at the time of initial crack formation by a suction action. I have to.

Next, the method of cutting glass according to the present invention is shown in FIG.
The description will be made mainly using the process diagrams of FIGS.

First, as shown in FIG.
Mother glass 1 at a predetermined position on a table 2
Place and fix. Next, the table 2 is moved in the X-axis and Y-axis directions by a preset distance,
The mother glass 1 is arranged at a first crack forming position (origin position: see FIG. 5A) by the scriber 3, and a first initial crack 15 (for example, in the X-axis direction) is formed on the surface of the mother glass 1 by the scriber 3. Several μm in depth, 100 μm in length
Degree).

At the time of the formation of the initial crack 15, FIG.
As shown in (1), a suction force is applied to a suction nozzle 10 provided in the vicinity of the scriber 3 to suction and remove fine dust generated at the time of crack formation. As a result, no dust adheres to the glass surface, and a highly clean working environment can be obtained.

The initial crack 15 is formed by moving the cutting edge of the scriber 3 from the inside to the outside while pressing the cutting edge against the surface of the glass 1. Thus, when the crack is formed, the scriber 3
Since a downward force is always applied to the cutting edge, when the cutting edge comes off the end surface of the glass 1, the cutting edge falls down. This causes chipping (dust) at the corners of the glass end surface. Therefore, in order to prevent the occurrence of the chipping, the fall prevention device 14 of the scriber 3 is laid on the table 2 along one side of the mounting table 13 when the blade of the scriber 3 comes off the end face of the glass 1. The cutting edge is received by the preventer 14 so that the cutting edge does not fall downward.

As described above, when the initial crack 15 is formed, the crack 15 is irradiated with the main heat source (main laser beam) 4 and the sub heat source (sub laser beam) 5 (for example, the main heat source 4 is substantially The perfect circular beam spot 4a, and the sub heat source 5 is a defocused oval beam spot 5a).
I do.

As shown in FIGS. 5B to 6D,
The two heat sources 4 and 5 described above are locally applied to the tip of the first initial crack 15, and the first initial stress is generated by the concentrated stress generated by the thermal stress generated between the central region and the peripheral region of the heat source. While growing the cracks 15 in the thickness direction of the glass 1, the heat sources 4, 5 are moved to the first position as shown in FIGS. 5B to 6D.
Is moved (the table 2 moves) along the planned cutting line 16 to cause the initial crack 15 to follow and extend in the same direction, and thereby, as shown in FIG.
Is cut (separated) into strip glass 1a.

The purpose of using the two heat sources 4 and 5 at the time of cutting the glass 1 is to equalize the thermal balance of the glass 1 on both sides (different in size and area) across the cut line 16. Thus, the cutting of the glass 1 is performed with high precision.

That is, as shown in FIG. 11 (B), when the thermal balance is lost, the crack does not propagate on the movement line of the heat source 4 (predetermined dividing line 16), and the crack does not move toward the free end of the glass 1. Propagation (bending) of the glass 1 occurs, and strong shearing stress is generated in the surface and thickness directions of the glass 1, and a difference (slope of the split surface) appears between the front and rear surfaces, resulting in poor processing accuracy.

Therefore, while applying the laser spot 4a of the main heat source 4 to the tip of the crack 15 formed in the glass 1,
By applying a laser spot 5a of the sub heat source 5 obliquely forward of the main heat source 4 (the side with the larger glass area) and moving the main heat source 4 and the sub heat source 5 along the planned cutting line 16, FIG. As shown in A), the thermal balance can be equalized, and the glass can be cut with high precision.

The distances L ₁ and L ₂ between the beam spots 4 a and 5 a of the main heat source 4 and the sub heat source 5 are adjusted according to the cutting position with respect to one end of the glass as shown in FIG. Then, an even thermal balance can be maintained on both sides of the scheduled cutting line 16. Accordingly, the distance L ₂ is gradually varied for each breaking of the glass 1 (less). Then, by moving the sub-heat source lens 7 for each fracture terminated based on programmed set number to the amount of change in advance control device, the distance L ₂ is adjusted. Incidentally, instead of changing the above distance L _2, the beam spot 5a
The thermal balance may be maintained by the strength of the power density.

As described above, by the movement control of the table 2 in the X-axis and Y-axis directions and the cooperative actions of the scriber 3 and the suction nozzle 10, and the main heat source 4 and the sub heat source 5, first, the first initial crack is formed. 15 is formed, and then the glass 1 is cut into strips along the planned cutting line 16 (first cutting step).
By repeating these operations sequentially, a large number of strip-shaped glasses 1a (see FIG. 10B) are formed along the planned cutting lines 16 as shown in FIG.

Thus, when the first cutting step of cutting the mother glass 1 into the strip-shaped glass 1a is completed, the table 2 which has been placed on the cutting stage K is moved to the standby stage T on the left and the right side. Is moved to the cutting stage K (the state of FIG. 2).

When the table 20 has been moved to the cutting stage K, the one piece of the strip-shaped glass 1a cut from the mother glass 1 is then transferred to the mounting table of the table 2 by a suitable conveying means (not shown). 13 is conveyed (supplied) onto the mounting table 21 of the table 20 and the conveyed strip glass 1a is mounted and fixed at a predetermined position on the mounting table 21 (FIG. 3, FIG.
(Fig. 4).

Thereafter, the table 20 is moved in the X-axis and Y-axis directions by a preset distance, and the strip glass 1a is arranged at the first crack forming position (origin position) by the scriber 3. , Strip glass 1a
A second initial crack 24 (for example, a depth of about several μm and a length of about 100 μm in the X-axis direction) is formed on the surface of the scriber 3 (see FIGS. 7A and 7B).

When the second initial crack 24 is formed, the fine dust is sucked and removed by the suction action of the suction nozzle 10 and the end face of the strip glass 1a is formed in the same manner as when the first initial crack 15 is formed. The cutting edge of the scriber 3 is received by the fall prevention tool 22 so that the corner is not chipped.

As described above, when the second initial crack 24 is formed in the strip glass 1a, the crack 24 is then irradiated with a heat source using a laser.
When the width is as small as about 5 mm to 20 mm, there is almost no influence of the accuracy due to the thermal balance collapse. In this case, only the main heat source 4 is irradiated as shown in FIG. To do. And the width of the glass 1a is 2
If the distance is 0 mm or more, it becomes necessary to equalize the thermal balance. In this case, as shown in FIG. 8D, the main heat source 4 and the sub heat source 5 are used to cut the mother glass 1 described above. The same cleaving operation as that described above is performed.

Main heat source 4 (or main heat source 4 and sub heat source 5)
From glass strip 1a to chip-shaped glass piece 1b
The cutting operation is the same as the cutting operation from the mother glass 1 to the strip glass 1a described above, and the main heat source 4 is moved along the second scheduled cutting line 25 (table 20).
As a result, the rectangular glass 1a is cut (divided) into small glass pieces 1b as shown in FIG. 10 (C).

However, when the glass piece 1b is cut, the size of the glass to be cut is small, so that there is a problem that the last piece is left uncut (about 0.5 mm to 1 mm) and is not completely cut. is there.

That is, in the cleaving method using a local heat source such as a laser beam, the crack tip follows the heat source as the heat source moves and the crack is developed by the progress of the crack. I have.

Therefore, as shown in FIG.
Is removed from the end of the strip-shaped glass 1a, the crack that follows thereafter stops growing at that point, and as a result, the glass end is left uncut. And if I try to forcibly break this residue, the crack will not go straight,
It is cut into a distorted state or a micro crack or the like is generated, resulting in a defective product.

Therefore, in order to solve the above-mentioned problem, according to the present invention, when the glass strip 1a is cut from the strip-shaped glass 1a into the chip-shaped glass pieces 1b, the cut glass 1a is cut.
As shown in FIG. 7 (C) to FIG. 8 (E),
By pressing the pressing tool 23 and applying an appropriate external stress to the end of the glass 1a with the pressing tool 23,
Even if the heat source 4 comes off the end of the glass 1a, the cracks continue to extend to the end as they are and complete glass fragments 1b (FIG. 8)
(F) and FIG. 10 (C)).

That is, when the heat source 4 comes off the edge of the glass,
The tensile stress, which had previously propagated the crack, decreases. The reduction in the tensile stress stops the growth of the crack. Therefore, a force equivalent to compensating only for the decrease in the tensile stress is applied by the pressing tool 23. Due to the pressing force of the pressing tool 23, even if the heat source 4 comes off from the glass end, the crack does not stop and continues to extend to the end of the glass, so that the glass is surely cut.

The pressing force and pressing position on the glass end by the pressing tool 23 are determined by the breaking speed, size, thickness,
It depends on conditions such as material and beam size. Therefore, the pressure applied to the glass by the pressing tool 23 and the pressing position are input to the control device in advance with a program whose conditions are set in advance.

As described above, the X-axis and Y-axis of the table 20
A second initial crack 24 is first formed in the strip-shaped glass 1a by the axial movement control and the cooperative action of the scriber 3, the suction nozzle 10, the main heat source 4 (the sub heat source 5) and the pressing tool 23, Next, the glass piece 1b is cut along the planned cutting line 25 (second cutting step), and these operations are sequentially repeated, so that a chip-shaped glass piece along the planned cutting line 25 as shown in FIG. 1b (FIG. 10)
(See (C)). Then, the cut small glass pieces 1b are stored in a predetermined tray by an appropriate conveying (pickup) means (not shown).

When all of the glass strips 1a mounted and fixed on the mounting table 21 of the table 20 are cut into small glass pieces 1b, the new glass strips 1a are then re-shaped.
Is supplied onto the mounting table 21 of the table 20 from the mounting table 13. Thereafter, the same operation as described above is repeated to cut the strip-shaped glass 1a into small glass pieces 1b.

As described above, according to the present invention, first, a large number of strip-shaped glasses 1a are cut from the mother glass 1 on the table 2 at a time. The glass is supplied on the table 20 and cut from the strip-shaped glass 1a into chip-shaped glass pieces 1b on the table 20, and this is sequentially repeated. However, the present invention is not limited to this. Glass 1a
May be supplied from the table 2 to the table 20 each time the cutting is completed.
May be cut into a plurality of sheets (2 to 3 sheets), and each time they are supplied onto the table 20 at one time.

In the embodiment of the present invention, the tables 2 and 20 are provided in one device, and the tables 2 and 20 are provided.
Are alternately arranged on the cutting stage K and the standby stage T
Although the cutting operation of the process is performed, it is also possible to provide one table in one device and perform the cutting operation for each process by two devices.

Further, in the above-described embodiment, the description has been made of the breaking of glass. However, the present invention is not limited to glass, and can be applied to all brittle materials such as ceramics, quartz substrates and silicon wafers. is there.

[0061]

As described above, according to the present invention, first, a first initial crack is formed on one surface of glass, and this initial crack is guided by a laser beam in a direction along a line to cut the glass. To cut the glass into strips,
A second initial crack is formed on one surface of the glass cut into strips, and finally, the second initial crack is guided by a laser beam in a direction along a line to cut the glass to separate the glass strips individually. Since the glass chip is cut into small pieces, the chipping does not occur when the glass is cut, and the yield is improved.

Further, since no cutting margin is required for cutting the glass, no cullet is generated, and since the laser beam is used, the cutting section has a surface close to a mirror surface. Since the glass can be simplified and no microcracks are generated, the strength of the glass is not reduced.

Further, by removing fine dust generated when the initial crack is formed by the scriber by suction and preventing chipping generated on the glass end face, the dust does not adhere to the glass surface and the work with high cleanness can be achieved. Environment is obtained.

Furthermore, when the glass strip is cut into small glass chips in a chip shape, one end of the glass is pressed by a pressing tool so that even if a heat source comes off from the glass end to be cut, cracks may occur. The growth is continued without stopping and reaches the end of the glass. As a result, the glass end is not cut off, and the glass is reliably cut.

[Brief description of the drawings]

FIG. 1 is a front view showing a first cleaving step of a cleaving apparatus used in a cleaving method of the present invention.

FIG. 2 is a front view showing a second cleaving step of the cleaving device used in the cleaving method of the present invention.

FIG. 3 is a front view of a table.

FIG. 4 is a plan view of a table.

FIG. 5A is a perspective view showing a state in which a first initial crack is formed in the mother glass, and FIG. 5B is a view showing an initial state in which the mother glass is subjected to a first cutting process by a laser beam. Perspective view.

FIG. 6C is an explanatory diagram showing a relationship between beam spots of a main heat source and a sub heat source, and FIG. 6D is a perspective view showing a state in which a first cutting process is being performed.

FIG. 7A is a perspective view showing a state in which a second initial crack is formed (entered) in a strip-shaped glass, FIG. 7B is a cross-sectional front view thereof, and FIG. 7C is a strip formed by a laser beam only from a main heat source. FIG. 4 is a perspective view showing a state in the middle of performing a second cleaving process on the glass sheet.

FIG. 8D is a perspective view showing a state in which the rectangular glass is being subjected to the second cutting processing by the laser beam from the main heat source and the sub heat source, and FIG. 8E is a state in which the main heat source is separated from the glass end; (F) is a perspective view showing a completed state of the second cleaving process.

FIG. 9 (G) is a side view of FIG. 8 (F).

10A is a perspective view showing a relationship between a mother glass and a cut (planned) line applied to the mother glass, FIG. 10B is a perspective view showing a strip glass cut from the mother glass, and FIG. The perspective view which shows the chip-shaped glass piece cut | disconnected from the strip-shaped glass.

FIGS. 11A and 11B are explanatory diagrams showing the relationship between the thermal balance of glass and the processing accuracy when breaking glass.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass 1a Strip glass 1b Glass piece 2, 20 Table 3 Scriber 4 Main heat source 5 Sub heat source 6 Lens for main heat source 7 Lens for sub heat source 8 Moving mirror 9 Fixed mirror 10 Suction nozzle 11 Laser oscillator 12 Guide mirror 13, 21 Mounting Table 21a Projection 14,22 Fall prevention device 15 First initial crack 16,25 Expected line 23 Pressing device 24 Second initial crack

Claims (4)

[Claims] 1. A step of forming a first initial crack serving as a processing start point on one surface of a glass substrate by a scriber, and cutting the first initial crack by thermal stress applied by a laser beam. A first cutting step of guiding the glass in a direction along the predetermined line and cutting the glass into strips;
Forming a second initial crack as a processing starting point by a scriber on one surface of the glass cut into a strip shape; and forming the second initial crack on the glass by thermal stress applied by a laser beam. A glass cutting method, wherein the glass is guided in a direction along a cutting line and cuts from the glass strip into individual chip-shaped glass pieces. 2. The glass cutting according to claim 1, wherein in the step of forming the first and second initial cracks, dust of the glass generated when the scriber forms the crack is sucked by a suction nozzle. Method. 3. The method according to claim 1, wherein the step of forming the first and second initial cracks includes, at the end of the glass, a fall prevention device for preventing a scriber from dropping after forming the initial crack. The method for cutting glass according to claim 1. 4. The glass cutting method according to claim 1, wherein in the second cutting step, a pressing means is provided at one end of the glass cut into small pieces to press the glass. .