JP2008229716A - Method and device for laser scribing, and cleaved substrate cleaved using the same method or the same device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for stably conducting a scribing treatment in an optimal state, and to execute a manufacturing method in an optimal state in a manufacturing step of cleaving a to-be-cleaved substrate. <P>SOLUTION: Before a to-be-cleaved substrate 10 is irradiated with a laser beam 702, the power of the laser beam is adjusted using a laser power measuring means. Further, when conducting a scribing treatment, temperature control of the to-be-cleaved substrate 10 is exercised. The focal point of a beam condensing means 752 is made to be positioned between the beam condensing means 752 and the to-be-cleaved substrate 10 in order to emit the laser beam 702 in an optimal state. The beam condensing means 752 for the laser beam 702 and the to-be-cleaved substrate 10 are made movable so that the laser power becomes optimal. The distance between an initial crack forming means 61 and the to-be-cleaved substrate 10 is made adjustable. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for cutting a brittle material plate such as a glass plate or a ceramic plate as a substrate to be cut using a laser beam.

  When performing the laser scribing process, if the scribing process is not performed in the optimum laser beam state, the appropriate cutting force can be used to properly cleave the substrate to be cut after the scribing process. The scribe process may not be possible.

  In addition, if the laser beam state is irradiated with excessive power during the scribing process, the level of the scribing process is exceeded, and the substrate to be cut is actually cut unnecessarily before the cutting process. As a result, the quality of the entire manufacturing process and the manufacturing process are disturbed. For example, the quality of the scribing process for manufacturing the substrate to be cut cannot be maintained.

  Next, when performing a scribing process as a pre-cleaving process on a substrate to be cut using a laser scribing device, it is important to control the temperature during the scribing process of the substrate to be cut. When the temperature of the substrate to be cut at the time of the scribing process is too high, it becomes difficult to draw a correct scribe line due to the expansion and distortion of the substrate to be cut. Therefore, in the present invention, consideration is given so that the temperature can be sufficiently controlled during the scribing process of the substrate to be cut.

  In addition, the present invention has a function of controlling the shape and laser power of the laser beam applied to the substrate to be cut.

Japanese Patent Application No. 2006-110534

  If it is not possible to control the irradiation power of the laser beam to an optimum value, there is a problem in that the quality of the scribe processing process for the substrate to be cut is defective and the entire manufacturing process is disturbed.

  In addition, it is considered that the scribe line can be processed at a correct position along the planned scribe line if the temperature control during the scribe process of the substrate to be cut is sufficiently performed.

  Further, if the laser beam power applied to the substrate to be cut at the time of the scribing process is too strong, it causes damage and becomes a problem. In order to solve the problem, the condensing means was devised for the laser beam irradiated to the substrate to be cut.

  When the scribing process is performed on the substrate to be cut, it is necessary to control the distance from the substrate to be cut when the initial crack is generated in order to obtain a scribe line having an optimum depth depending on the properties of the substrate to be cut.

  In the present invention, an apparatus is provided for a method and apparatus for stably performing the optimum scribing process on the substrate to be cut, and the manufacturing method can be performed in an optimum state.

  That is, when performing laser irradiation of a laser scribing device, first, as preparation, so that the laser power can be adjusted to a stable beam power so that the optimal scribing process can be performed on the substrate to be cut, In order to adjust the laser power from the laser oscillation means to the optimum laser power for the preset laser scribing process before starting the actual scribing process on the substrate to be cut, In order to confirm in advance whether the power level is optimum by applying power, the laser power is oscillated from the laser oscillation means to the laser power measurement means provided, and the laser power is measured while measuring the laser power. adjust.

  This makes it possible to carry out a scribing process before the cutting process for a stable substrate to be cut.

  Furthermore, in order to perform an optimal laser scribing process on the substrate to be cut, it is important not only to adjust the laser power but also to process the scribe line without shifting the line of the planned scribe line. In order to process the correct scribe line, it is important to irradiate the optical path of the laser beam in the optimum direction. The laser beam emission direction can be selected and changed simultaneously with the power adjustment.

  Next, in order to be able to control the temperature of the substrate to be cut itself during the laser scribing process, the surface temperature measuring means of the substrate to be cut is provided along with the laser oscillation means that has been damaged, The surface temperature can be measured.

  In addition, by setting and registering the temperature at which the optimum scribing process can be performed in advance, the processing is performed by controlling the laser power so as to reach the planned processing temperature compared to the processing temperature and the temperature during the descent. It is possible to ensure the quality of the scribing process.

  Next, a laser beam condensing unit that irradiates the substrate to be cut so that the substrate to be cut is scribed, an optimum scribe line is processed, and the cutting is performed at a desired position in the subsequent cutting step. We devised it to become the most suitable state.

  The heating beam for the substrate to be cut is thin in the X direction and long in the Y direction. The X direction is narrower than the beam after being emitted from the laser. Accordingly, a condensing means is used to condense the laser light. In the present invention, a transmission material having a convex surface is used as the light collecting means.

  The laser beam after passing through the lens is condensed at a predetermined distance from the lens and becomes a very thin beam. When the substrate to be cut is heated at this condensing point, the energy density is too high, and the substrate is damaged. For this reason, it is necessary to dispose the substrate to be cleaved at a location where the focal point is shifted, that is, between the lens and the focal point. However, in this case, the condensing point may overlap a portion on the suction table where the substrate to be cut is not placed. When the laser is focused on the suction table, the suction table is damaged. Therefore, the present invention is designed so that a focusing point is formed between the lens and the substrate to be cut.

  Examples of the condensing means include not only a transmissive material having a convex surface but also a reflective material having a non-planar surface, specifically, a reflective material having a concave surface. The reflective material is a metal (copper, aluminum, silicon) coated with a metal (gold, silver, copper, aluminum, etc.) or a dielectric multilayer film on the same as other flat mirrors.

  A laser beam condensing unit for performing laser scribing processing is provided with at least one condensing unit, and a unit for changing the distance between the condensing unit and the substrate to be cleaved, The beam shape on the substrate can be changed. In addition, at least one condensing means and means for changing the distance between the condensing means and the substrate to be cut are provided, and the power density (power per unit area) of the beam on the substrate to be cut is changed. It was possible.

  A scribe line initial crack generating means, a means for changing the distance between the initial crack generating means and the substrate to be cut, and a means for measuring the distance are provided, and the distance is measured before the initial crack generation. Yes.

  As described above, in proceeding with the cleaving process of the substrate to be cut, in the scribing process of the previous step, by maintaining the optimum depth and straightness, in the scribing process before the step of cleaving the substrate to be cut, The apparatus is provided so that the optimum scribing process can be performed to stably operate the cutting process of the substrate to be cut.

  By measuring the surface temperature of the substrate to be cut at the time of the scribing process, and maintaining the optimum temperature by controlling the laser beam power to the surface temperature of the substrate to be cut to the preset and registered temperature, It can eliminate distortion and draw good quality scribe lines.

  In this invention, it designed so that a condensing point might be made between a lens and a to-be-cleaved board | substrate. In this way, the problem that occurs when the suction table is irradiated with the laser beam is eliminated.

  Further, when a scribing process is performed on the substrate to be cut, it is necessary to adjust the distance between the initial crack generating means and the substrate to be cut to an optimum state when the initial crack is generated. Therefore, in the present invention, the distance can be measured and changed.

  A laser scribing apparatus will be described with reference to FIG.

  The laser scribing apparatus 1 is composed of a main unit 2, a control panel box 30, a table unit 4, an alignment unit 5, and a scribe head unit 6.

  The main body 2 is composed of members including a main body frame 21, a sub frame 211, a cover 212, and the like, and includes a control panel box 30, an operation unit 31, a table unit 4, an alignment unit 55, and a scribe head unit 6, which are arranged respectively. Has been.

  Next, as shown in FIG. 2, the main body 2 is accompanied by a maintenance cover frame 22. The maintenance cover frame 22 is composed of members such as a cover 222 and a frame that separate the inside of the apparatus from the outside of the apparatus.

  A part of the maintenance cover frame 22 is an exterior cover of the apparatus, and a part thereof is configured to overlap with the apparatus exterior cover. The state at the time of the maintenance is shown in FIG.

  When the apparatus is in operation, the maintenance cover frame 22 is disposed so as to overlap the apparatus exterior cover as indicated by reference numeral 224 in consideration of minimizing the apparatus installation area.

  During equipment maintenance, the maintenance cover frame 22 is designed so that the portion 225 that overlaps the equipment outer cover is minimized, and is designed so that an operator can enter and work inside the equipment. ing.

  Next, in the control panel box 30, as a device called a control device, a numerical operation device (so-called personal computer, PLC, sequencer, NC controller, etc.), breaker, relay, motor amplifier, transformer, DC power supply device, noise filter A device including a signal input unit, a signal output unit, an A / D conversion unit, a motor positioning unit, a signal counter, a timer, etc. is connected and stored. These devices may be appropriately placed outside the control panel for convenience in the device layout.

  As shown in FIG. 2, the operation unit 31 is configured and installed as an information display unit and an information input unit on the cover 212 of the laser scribing apparatus 1.

  The information input unit is composed of devices including a keyboard 332 and an operation SW (mouse) as information input means.

  The information display unit also serves as an information output unit, and is configured by devices including an information display 331 and a display lamp.

  The keyboard 332 of the information input unit is connected to the numerical arithmetic unit of the laser scribing apparatus 1 and has a role of inputting and registering operation commands and setting values from the operator.

Similar to the information input unit, the information output unit also serves as an information display unit and is connected to the numerical arithmetic unit of the laser scribing apparatus 1 and has a role of transmitting the state and information of the apparatus and devices in the apparatus to the operator.
In addition to the information output means, a buzzer, a speaker, a display meter, etc. can be used as appropriate.

  As shown in FIGS. 1 and 4, the table unit 4 is configured by a member including a stage unit 43-a that moves a table main body unit 43 on which the substrate 10 to be cut is placed. The stage unit 43-a is centered on the vertical direction with the driving unit 41 orthogonal to the XY two axes so that the stage unit 43-a can move in the horizontal direction (X (left and right) 411 · Y (front and rear) 413 direction indicated by arrows in FIG. 1). A θ-axis rotating portion 415 is included and is attached to the stage portion 43-a and the main body frame 21 so as to be rotatable in the horizontal direction (θ direction indicated by the arrow in FIG. 1).

  A winding cover 42 may be installed on the stage unit 43-a. Two winding covers 42 are attached to one axis of the stage portion 43-a. Each take-up cover 42 can be expanded and contracted in accordance with the operation of the stage portion 43-a, and has a role of preventing foreign matter from entering the inside of the stage from the outside.

  The table main body 43 includes a suction table 431 and an intermediate plate. The suction table 431 is flat in the XY direction and has a shape on which the cut substrate 10 can be placed.

  The suction table 431 is provided with a groove called a suction groove or a hole called a suction hole in a part of a portion in contact with the substrate 10 to be cut, through a vacuum chamber 434, a pipe hose or a pipe joint not shown. To the vacuum pump. The to-be-cut substrate 10 placed on the suction table 431 is brought into close contact with the suction table 431 by setting the suction grooves and suction holes to a negative pressure, so that the position does not shift even if the suction table 431 moves at a high speed. .

  Although not shown between the suction table 431 and the table main body 43, an intermediate plate is provided and attached via a plurality of screws and fasteners. The screws and fasteners of the intermediate plate are used for adjusting the level and flatness of the suction table 431.

  The suction table 431 may be provided with a member called a suction subtable.

  The suction sub-table 440 is disposed between the substrate to be cut 10 and the suction table 431 and is attached to the suction table 431.

  The suction sub-table 440 has a shape in which only a part of the substrate 10 to be cut contacts.

  The position where the suction sub-table 440 supports the substrate to be cut 10 can be exemplified by the outer peripheral portion or the four corners of the substrate to be cut 10, and further, the center portion of the substrate to be cut 10 or other places can also be exemplified.

The suction table 431 is provided with an exhaust pan (not shown).
The exhaust pan communicates with a negative pressure suction device such as a blower via a piping tube, a mist separator, and the like. The mist ejected from the nozzle in the scribe head 6 is collected through an exhaust pan so that the mist does not remain on the suction table.

  The alignment unit 5 includes a camera unit 52 and a camera driving unit 521. The camera unit 52 includes an imaging camera 521, a device including a lens, illumination, and the like. As the imaging camera 521, a CCD camera, a CMOS camera, or the like is used.

  The imaging camera 521 has a function of observing a part of the marks on the cut substrate 10 or the posture and outline of the cut substrate 10. The imaging camera 55 and the image processing unit are connected via a signal cable, and an image observed by the imaging camera 521 is transmitted to the image processing unit. The image transmitted to the image processing unit is output to the information display unit 331 as appropriate.

  The lens serves to form an image of a part of the mark on the cut substrate 10 or an outline of the cut substrate 10 on the imaging camera 521.

  The illumination serves to brighten some marks on the substrate to be cut 10 or the outer portion of the substrate to be cut 10 so that the image can be easily observed by the imaging camera 521. Illumination includes an LED light source, a halogen light source, a metal halide light source, a white light bulb, a fluorescent lamp, and the like, and a dimming means for adjusting brightness may be provided.

  The camera driving unit 55 is configured by members including a camera fixing unit, a stage unit, and the like. The image processing unit is composed of devices including an image processing board mounted on a personal computer and a general-purpose image processing apparatus.

  As shown in FIG. 6, the scribe head unit 6 includes an initiator unit 61, a laser heating unit 7, and a mist cooling unit 8.

  The initiator unit 61 includes a scribe wheel 65 and a wheel head unit 63. A scribe wheel 65 is attached to the wheel head portion 63 via a pin 64. Since the pin 64 has a cylindrical shape, the scribe wheel 65 is rotatable so as not to drop or rub against the wheel head 65.

  The wheel head portion 63 includes a Z-axis positioning mechanism 622 so that the scribe wheel 65 can move in a vertical direction (Z direction in the case of the apparatus) with respect to a plane direction (XY direction) formed by the substrate 10 to be cut. Has been placed.

  The laser heating unit includes a laser oscillator 71, a mirror unit 73, a lens unit 75, and a laser control unit 77. The laser oscillator 71 is attached to the main body frame 21. As the laser oscillator 71, a carbon dioxide laser (CO, CO2 laser) is used. The beam emitted from the laser oscillator 71 is applied to the cut substrate 10 via a mirror or a lens. An appropriate number of mirror units 73 are used to change the direction of the laser beam emitted from the laser oscillator 71. At least one lens is used, and the shape is such that the beam emitted from the laser oscillator 71 can be efficiently heated to the substrate to be cut 10.

  Instead of using a lens, it is possible to efficiently heat the substrate to be cut 10 by using a mirror having a non-planar reflecting surface as in the case of using a lens. The mirror should be made of a material that reflects the laser efficiently. Metal (gold, silver, copper, aluminum, etc.) or a dielectric multilayer film is coated on the metal (copper, aluminum, silicon, etc.). Is used.

  The mirror unit 73 includes a mirror 732 and a mirror holder, and may be used by appropriately cooling as well as natural cooling. As a means for cooling the mirror 732, it is cooled by an air cooling method in which a large number of fins are brought into contact with the mirror 73 or the mirror holder, or by a unit that circulates water or fluid at a predetermined temperature in contact with the mirror 73 or the mirror holder. There is a water cooling system to do.

  The lens unit 75 includes a lens holder 751 and a lens 752, and it is desirable to use a material that efficiently transmits the laser. In the case of a carbon dioxide laser, ZnSe (zinc selenide) or Ge (germanium) is used. The In addition to natural cooling, the lens may be used after being cooled appropriately.

  The laser control unit 77 outputs an electric signal for power control to the laser oscillator 71 or an amplifier unit connected to the laser oscillator 71 so as to obtain a desired laser output. The amplifier unit may be built in the laser oscillator 71 or may be installed separately from the laser oscillator 71. The amplifier unit installed separately from the laser oscillator 71 is installed in the scribe device 1 as appropriate. A high-frequency pulse voltage, a direct current, or the like is used as an electric signal for power control.

  Next, the chiller 714 will be described. The laser oscillator 71 and the amplifier unit often require forced cooling in addition to natural cooling. As a means for cooling the laser oscillator 71, an air cooling system in which a large number of heat radiation fins are attached to a part of the housing of the laser oscillator 71 can be exemplified. In the case of the air cooling method, there is one that increases the cooling efficiency by using a blower together. As a means for cooling the laser, a water cooling method can be used in addition to the air cooling method. The water cooling method is a method in which the temperature of the casing of the laser oscillator 71 is transmitted to the cold water supplied from the outside and released to the outside. As a refrigerant, a solution containing ethylene glycol in addition to water, a method containing oils, etc. are also broadly defined and referred to as a water cooling method.

  As shown in FIG. 1, FIG. 4 or FIG. 6, the mist cooling unit includes a water supply unit 81, an air supply unit, and a nozzle 83. The water supply unit 81 includes a water supply tank on the main body frame 21 or pressure adjusting means such as a pressure pump or a regulator for sending water supplied from the outside of the apparatus at a predetermined pressure, and a liquid supply tube. The air supply unit includes pressure adjusting means such as a pressurizing pump and a regulator for sending out air supplied from the blower 26 outside the apparatus at a predetermined pressure, and a piping tube. The nozzle 83 has a structure in which water sent from the water supply unit and air sent from the air supply unit 82 are mixed to form a mist to be sprayed onto the substrate to be cut 10. At least one or more nozzles 83 are used. When a plurality of nozzles 83 are used, a plurality of water supply units are appropriately arranged.

  The mist suction unit 85 includes a suction nozzle 851, a piping hose, a mist separator 852, and an exhaust fan. The suction nozzle 851 is disposed in the scribe head 6 and communicates with a mist separator and an exhaust fan through a piping hose. The mist separator and the exhaust fan are disposed on the main body frame 21 in the scribing apparatus main body 2 or outside the scribing apparatus. The mist separator has a role of separating moisture in the exhaust air and preventing corrosion of the exhaust fan. The exhaust fan is used for making the tip of the suction nozzle 851 have a negative pressure and sucking air at a predetermined flow rate. As the exhaust fan, an axial fan, a centrifugal fan, a diagonal fan, or the like is used, but a vacuum pump can also be used.

  The mechanism for limiting the mist spray area will be described. The mist supplied from the nozzle 83 of the mist cooling unit is not only sprayed directly on the substrate 10 to be cut, but may also be sprayed through a plate having a predetermined shape and an opening having a predetermined area. it can. By passing the plate, the spray area of mist can be made narrower than when spraying directly.

  Next, as shown in FIG. 5, the change of the beam irradiation position will be described. At least one of the mirror and the lens can be changed in position, and when the beam incident direction is the Z direction, it is a uniaxial or biaxial direction orthogonal to the Z direction (so-called X direction and / or Y direction). ) So that the position can be changed. By changing the position of the mirror and / or the lens, it is possible to change the irradiation position of the laser beam irradiated to the substrate to be cut 10. As the position changing means in the X direction and / or the Y direction, a direct-acting actuator (not shown) is raised, and includes a cylinder, a rotary motor, a ball screw, a linear motor, and the like. This direct acting actuator is connected to a control device and can be appropriately positioned.

  As for the beam shape, at least one of the lenses is arranged so that the position thereof can be changed and the distance from the substrate to be cut 10 can be changed. By changing the position of the lens, the dimension of the laser beam irradiated onto the substrate to be cut 10 is changed. As a lens position changing means, a direct-acting actuator is raised, and is composed of a cylinder, a rotation motor, a ball screw, a linear motor, and the like. This direct acting actuator is connected to a control device and can be appropriately positioned.

  The power meter 72 is installed inside the laser scribing apparatus 1 as a means for measuring the power of the laser emitted from the laser oscillator. The power meter 72 includes a main body unit 2 housing, a laser light receiving unit 724, a temperature sensor unit, and a control unit. The laser light receiving unit 70 receives the laser, an electrical signal is output from the temperature sensor unit, and amplification processing and filter processing are performed by the control board 77. The laser beam emitted from the laser oscillator of the laser unit 7 is irradiated to the laser light receiving unit of the power meter head unit when the substrate to be cut 10 is not irradiated. Whether the beam emitted from the laser oscillator is applied to the cut substrate 10 or the power meter can be selected by changing the position and angle of the mirror. As means for changing the position and angle of the mirror, a direct acting actuator and a rotary actuator can be raised. This actuator is connected to the control device 77 and can be appropriately positioned. The measurement value measured by the power meter 72 is converted into an electrical signal and output, and is input to the control board 77. Since an electric signal is output from the power meter 72 according to the power of the irradiated laser beam, the power of the laser beam can be measured on the control device side.

  The power meter chiller 726 will be described. The head of the power meter 72 includes a head that does not require cooling and a head that requires cooling. As a means for cooling the head of the power meter 72, an air cooling method in which a large number of heat radiation fins are attached to a part of the head housing of the power meter 72 can be exemplified. In the case of the air cooling method, there is one that increases the cooling efficiency by using a blower together. Further, as a means for cooling the head of the power meter 72, a water cooling method can be raised in addition to the air cooling method. The water cooling method is a method in which the temperature of the head casing of the power meter 72 is transmitted to the cold water supplied from the outside and released to the outside. As a refrigerant, a solution containing ethylene glycol in addition to water, a method containing oils, etc. are also included in a broad sense, and any water cooling method may be used. In the case of the water cooling method, there are cases where the cooling water supply source is independent for cooling the laser oscillator and for cooling the head portion of the power meter 72 and is common.

  The substrate displacement sensor 66 is installed inside the scribe head 6 and can measure the distance between the scribe head 6 and the substrate to be cut 10. As the substrate displacement sensor 66, a contact type or non-contact type is used. The measurement value measured by the substrate displacement sensor 66 is converted into an electrical signal, output, and input to the control device in the control panel box 30. Since an electric signal is output from the substrate displacement sensor in accordance with the distance between the scribe head 6 and the substrate 10 to be cut, the distance can be measured on the control device side.

  The substrate surface temperature sensor 781 is installed inside the scribe device 1. The substrate surface temperature sensor 781 can be used to measure the surface temperature of the substrate to be cut 10 in the scribe device 1. The measurement value measured by the substrate surface temperature sensor 781 is converted into an electrical signal and output, and is input to the control device in the control panel box 30.

  The observation camera section will be described. An observation camera may be installed in the scribe device 1 or the scribe head 6. The observation camera unit includes a camera unit and a camera drive unit. The camera unit is composed of devices including an imaging camera, a lens, illumination, and the like. A CCD camera, a CMOS camera, or the like is used as the imaging camera. In addition, the camera unit has a function of observing a part or all of the pattern, posture, and outline of the object to be observed. The camera unit and the image processing unit are connected via a signal cable, and an image observed by the imaging camera is transmitted to the image processing unit. The image transmitted to the image processing unit is appropriately output to the information display unit. The lens has a function of forming an image of a part of the marks on the substrate to be cut 10 or an outline of the substrate to be cut 10 on the imaging camera. The illumination in that case has a role of brightening a part of the marks on the cut substrate 10 or the outline of the cut substrate 10 so that it can be easily observed with the imaging camera. Illumination includes an LED light source, a halogen light source, a metal halide light source, a white light bulb, a fluorescent lamp, and the like, and may have dimming means for adjusting brightness.

  The laser scribing apparatus 1 may be provided with clean air supply means called a local clean unit. Further, an exhaust blower that exhausts the air in the apparatus to the outside is installed as necessary.

  Next, a method for performing a laser scribing process on the substrate to be cut 10 using the above apparatus will be described.

  Examples of the substrate to be cut 10 include glass plates used for FPD (Flat Panel Display) such as portable information terminals, personal computer monitors, and thin TVs.

  The glass plate for FPD passes through various manufacturing processes with a large substrate size called mother glass, and is then cut out in panel units of the final product size. Examples of the material for the glass plate include materials called soda lime glass and non-alkali glass.

  First, the substrate to be cut 10 is placed on the suction table and sucked.

  When the alignment mark is not arranged on the surface of the substrate to be cut 10, a method of performing alignment based on the outer shape reference of the substrate to be cut 10 can be selected. As a method for reference of the outer shape of the substrate 10 to be cut, a method in which an operator adjusts the position with reference to marks or lines engraved on the table portion 43, or a projection serving as a positioning reference is arranged on the table portion 43 to make glass. For example, there is a method to bring the board along.

  When the alignment mark is arranged on the surface of the substrate to be cut 10, the substrate to be cut 10 may be placed in a state slightly deviated from the suction table 431.

  The alignment mark is read by the alignment camera, and the deviation amount of the substrate to be cut 10 is calculated by the numerical calculation device of the control panel box 30. The numerical operation device performs a correction operation for correcting the posture of the substrate to be cut 10 based on the shift amount of the substrate to be cut 10 and the position information of the table. The table 41 on which the substrate 10 to be cut is placed moves to the thickness measurement position of the substrate 10 to be cut and measures the distance between the scribe head unit 6 and the surface of the substrate 10 to be cut. The control device adjusts the height of the initiator 61 based on the measured distance information.

  The table unit 43 moves to a scribing process start position at a predetermined speed. During the movement of the table portion 43, an extremely small crack is formed in the surface portion of the end face of the substrate to be cut 10 by the initiator 61. This small crack becomes the starting point of the laser scribing process.

  A laser beam is applied to the scribe head 6 from the laser oscillator 7. The laser beam is formed into a beam shape optimum for the scribing process by a lens in the scribe head 6 and irradiated on the surface of the substrate to be cut 10. Since the substrate to be cut 10 is moving at a predetermined speed while being irradiated with the laser, it is continuously heated with respect to the scribe line 111. At this time, compressive stress is generated on the surface of the substrate to be cut 10.

  Immediately after the substrate 10 to be cut is heated by the laser, the mist is sprayed from the nozzle 83 of the mist cooling unit 8 and cooled. At this time, a tensile stress is generated on the surface of the substrate to be cut 10.

Due to the heating and cooling cycle described above, changes in compressive and tensile stress occur on the surface of the cut substrate 10. This compression and tensile stress change is continuously performed as the substrate to be cut 10 moves.
At this time, small cracks in the surface portion of the end surface of the substrate to be cut 10 formed by the initiator 61 continuously spread. This continuous crack is the scribe line 112. Note that the scribe line 112 cannot be normally recognized visually.

  Based on pre-registered scribing process condition information, a scribing process is performed on a predetermined position on the substrate to be cut 10. If necessary, the posture of the substrate to be cut 10 is changed, and a scribing process is performed. By repeating the above operation as many times as necessary, scribe lines are formed in a lattice shape.

  The substrate 10 to be cut is taken out of the apparatus, and the substrate 10 to be cut next is placed on the table.

  Since the bonded substrate made of the substrate to be cut 10 needs to be scribed on each side, after the first surface is scribed, the substrate to be cut 10 is turned upside down and the second surface is placed toward the scribe head 6 side. Put. When the reversing mechanism is attached to the scribe device 1, the substrate to be cut 10 is reversed by the reversing mechanism and then placed on the table unit 43. The substrate to be cut 10 that has been subjected to the scribing process is cut by applying a necessary external force along the scribe line, and is cut into strips or pieces.

  Stripping means that a plurality of panels are connected in a row, and singulation means a state where the plurality of panels are individually separated.

  When the bending stress acts along the scribe line 112, the crack spreads and the substrate to be cut 10 is cut.

The laser beam 701 emitted from the laser transmitter 713 of the laser unit 71 is applied to the power meter unit 72. The power meter 72 is provided with a reflecting material 723 and position changing means or angle changing means capable of changing the position or angle of the reflecting material. Examples of the reflecting material include a reflecting mirror, and the angle changing means includes a rotary actuator. As a means for changing the position of the reflection mirror, a direct acting actuator can be exemplified.
FIG. 6 shows the position of the reflector at the time of laser power measurement. The laser beam 701 after emitting the laser beam is reflected by the reflecting material 723 and irradiated to the power meter 724, and the laser power can be measured during laser oscillation.
FIG. 7 shows the position of the reflective material during laser scribing. The reflecting material 723 is removed from the optical path of the laser beam 701 after emitting the laser, and is emitted to the outside of the power meter unit 72. As shown in FIG. 1, the laser beam 701 emitted to the outside of the power meter unit 72 is reflected by the mirror 723 and irradiated onto the scribe head unit 6.
Since the position and angle of the reflector can be changed as described above, the laser power can be measured when the laser is not emitted to the substrate to be cut. Further, since the laser can be continuously oscillated even when the apparatus is stopped, it is possible to improve the output stability of the laser and the stability of the laser irradiation position called pointing stability.

Further, in the invention of controlling to a preset temperature using the surface temperature measuring means of the substrate to be cut,
As shown in FIG. 4, a substrate surface temperature sensor 781 is placed on the scribe head unit 6. The substrate surface temperature sensor is placed so that the surface temperature of the substrate to be cut after being heated by the laser can be measured. Although not shown, the substrate surface temperature sensor 781 is connected to the control unit 3.

  As the substrate surface temperature sensor 781, an infrared detection type sensor capable of capturing thermal radiation emitted from the surface of the substrate to be cut was used.

  The surface temperature measured by the above means is provided with a function that can be compared with a preset output command value by a numerical arithmetic unit in the control unit 3 when irradiating a laser to the substrate to be cut. . As a result of comparing the surface temperature with the output command value, if there is a deviation, the output command value was corrected to minimize the deviation amount. For example, if the surface temperature is higher than the output command value, the output command value is lowered so that the surface temperature is lower. Conversely, if the surface temperature is lower than the output command value, the output is made so that the surface temperature is higher. Increased the command value. By repeating such comparison and adjustment, the laser power was adjusted so that the temperature during actual processing approached the planned processing temperature.

  Next, a laser beam condensing unit, which is configured as follows, was subjected to a scribing process.

That is, as shown in FIG. 4, the heating beam for the substrate to be cut is thin in the X direction and long in the Y direction. The X direction is narrower than the beam 702 after being emitted from the laser.
In order to condense the laser beam, a condensing unit is used. In the present invention, a lens is used as the condensing unit. This lens was made of a transmissive material having a convex surface.

  The laser beam after passing through the lens is condensed at a predetermined distance from the lens and becomes a very thin beam. When the substrate to be cut is heated at this condensing point, the energy density is too high and the substrate is damaged. For this reason, it is necessary to dispose the substrate to be cleaved at a location where the focal point is shifted, that is, between the lens and the focal point. However, in this case, the condensing point may overlap a portion on the suction table where the substrate to be cut is not placed. In that case, if the laser is focused on the suction table, there arises a problem that the suction table is damaged.

  In the present invention, since the condensing point is designed to be formed between the lens and the substrate to be cut, there is no problem caused by the irradiation of the laser beam on the suction table.

  Examples of the condensing means include not only a transmissive material having a convex surface but also a reflective material having a non-planar surface, specifically, a reflective material having a concave surface. The reflective material used was a metal (copper, aluminum, silicon) coated with a metal (gold, silver, copper, aluminum, etc.) or a dielectric multilayer film on the same as other flat mirrors.

  In the present invention, the light collecting means and means for changing the distance between the light collecting means and the substrate to be cut are provided, and the power density of the beam on the substrate to be cut (power per unit area) can be changed. .

  The lens position change will be described with reference to FIGS. A laser beam 701 emitted from the laser is irradiated into the scribe head unit 6, reflected by the mirrors 732 e and 732 f, then becomes a laser beam 702 before passing through the lens, and is irradiated onto the lens 763 at the first position. The laser beam 703 after passing through the lens at the first position becomes a heating beam 705 formed by the lens at the first position, and is irradiated onto the substrate to be cut 10. Here, the distance between the substrate to be cut 10 and the lens 763 at the first position is L1. The laser beam on the substrate to be cut at this time has a profile 707 shown in FIG.

  As shown in FIG. 8, the lens is arranged on a lens position changing means 762 that can move in the direction of an arrow 761 via a lens holder. The lens position changing means 762 is disposed on the base plate 743 on the scribe head, and has a structure capable of changing the position of the lens with respect to the substrate to be cut.

  FIG. 9 shows a state after the lens position is moved. The laser beam 702 before passing through the lens is applied to the lens 764 at the second position. The laser beam 704 after passing through the lens at the second position becomes a heating beam 706 formed by the lens at the second position, and is irradiated onto the substrate to be cut 10. Here, the distance between the substrate to be cut 10 and the lens 764 at the second position is L2. The laser beam on the substrate to be cut at this time has a profile 708 shown in FIG. The profile here refers to the energy distribution of the laser beam.

  FIG. 10 shows an embodiment in which two lenses are used. The laser beam 702 before passing through the lens is irradiated onto the lens 752b at the first position, and the laser beam 703 that has passed through the lens 763b at the first position becomes a heating beam 705 formed by the lens at the first position. Irradiated onto the substrate to be cut 10. Here, the distance between the substrate to be cut 10 and the lens 763b at the first position is L1, and the distance between the lens 752b and the lens 763b is L3.

FIG. 11 shows a state after the lens position is moved.
The laser beam 702 before passing through the lens is irradiated onto the lens 752b at the second position, and the laser beam 704 that has passed through the lens 764 at the second position becomes a heating beam 706 formed by the lens at the second position. Irradiated onto the substrate to be cut 10. Here, the distance between the substrate to be cut 10 and the lens 764 at the first position is L2, and the distance between the lens 752b and the lens 764 is L4.

  In addition, the position of the lens 752b can be changed. There are various lens positions, not only the first position and the second position, and can be changed each time. It goes without saying that the profile changes as the lens position changes.

  The laser scribing apparatus provided with all or a part of the mechanisms and means described above can easily produce a higher quality product than conventional apparatuses.

  In a method of scribing a substrate to be cut using a laser scribing apparatus, the substrate to be cut is glass used for FPD (Flat Panel Display) such as a portable information terminal, a monitor for a personal computer, and a thin TV. It can be used as a substrate.

  Moreover, the glass plate for FPD passes through various manufacturing processes with a large substrate size called mother glass, and is then cut out in panel units of the final product size. Examples of the glass plate material include so-called lime glass and non-alkali glass.

The figure which shows the outline | summary of the "laser scribing apparatus" of this application. The figure which shows "the external appearance of the laser scribing apparatus at the normal time" of this application. The figure which shows the "appearance at the time of the maintenance of a laser scribing apparatus" of this application. The figure which shows the "detail of a scribe head" of this application. Schematic which shows "the structure of a scribe head" of this application. The figure which shows "laser irradiation to the laser power measurement means" of this application. The figure which shows the case where "a laser power is irradiated to a to-be-cut substrate" of this application. Schematic showing "beam shaping with a lens in a first position" of the present application. Schematic which shows "the beam shaping in the 2nd lens position" of this application. Schematic which shows "the beam shaping in the 1st lens position" of this application. Schematic which shows "the beam shaping in the 2nd lens position" of this application. The figure which shows "the profile of the heating beam in the lens of the 1st position" of this application. The figure which shows "the profile of beam shaping in the lens of the 2nd position" of this application.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laser scribing apparatus 10 Substrate to be cut 111 Scribing line 112 Scribing line 2 Main body part 30 Control panel box 331 Information display part 43 Table main body part 43-a Stage part 431 Adsorption table 440 Adsorption subtable 55 Camera drive part 521 Imaging camera 6 Scribe head unit 61 Initiator unit 7 Laser heating unit 701 Laser beam 702 Laser beam 704 Laser beam 706 Heating beam 71 Laser transmitter 713 Laser head 72 Power meter 721 Shutter function 723 Mirror 724 Light receiving unit 752 Lens 763 Lens 764 at the first position Second position lens 781 Substrate surface temperature sensor 8 Mist cooling section

Claims (28)

    Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In the laser scribing method, a laser scribing method comprising laser transmitting means and laser power measuring means, and irradiating a laser power measuring device with a laser beam before the scribing process for the substrate to be cut.     2. The laser scribing method according to claim 1, wherein the laser power measuring means side irradiates and adjusts by means for sequentially adjusting so as to obtain a predetermined power.     3. The laser scribing method according to claim 1, wherein the scribing process is performed by emitting laser to the substrate to be cut using the laser oscillation means and the laser power measuring means.     The movable reflecting material is arranged on the optical path of the laser beam, and the emitting direction of the laser beam is selectively changed by changing the position and / or angle of the reflecting material. The laser scribing method according to any one of claims.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. A laser scribing apparatus comprising a laser transmitting means and a laser power measuring means, and irradiating the laser power measuring apparatus with a laser beam before scribing the cut substrate.     6. The laser scribing apparatus according to claim 5, wherein means for sequentially adjusting the laser power measuring means side to irradiate the laser power measuring means side so as to obtain a predetermined power is held.     7. The laser scribing apparatus according to claim 5, wherein the scribing process is performed by emitting laser to the substrate to be cut using the laser oscillation means and the laser power measuring means.     A movable reflecting material is disposed on the optical path of the laser beam, and the emitting direction of the laser beam can be selectively changed by changing the position and / or angle of the reflecting material. The laser scribing device according to claim 7.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In the laser scribing method, a laser scribing method characterized by using a laser transmitting means and a surface temperature measuring means of the substrate to be cut.     10. The laser scribing method according to claim 9, further comprising means for presetting and registering the temperature of the substrate to be cut to be processed, and comparing the processing scheduled temperature with the temperature during processing.     11. The laser scribing method according to claim 9, wherein the laser power is adjusted so that the temperature of the substrate to be cut that is to be processed approaches a planned processing temperature.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. A laser scribing apparatus comprising a laser transmitting means and a surface temperature measuring means for a substrate to be cut.     13. The laser scribing apparatus according to claim 12, further comprising means for presetting and registering the temperature of the substrate to be cut to be processed, and comparing the processing scheduled temperature with the temperature during the processing.     13. The laser scribing apparatus according to claim 11, wherein the laser power is adjusted so that the temperature of the substrate to be cut that is to be processed approaches a planned processing temperature.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In the laser scribing method, a laser scribing method comprising at least one condensing unit, wherein the condensing point is between the condensing unit and the substrate to be cut.     The laser scribing method according to claim 15, wherein the condensing means uses a transmissive material having a convex surface.     The laser scribing method according to claim 15 or 16, wherein the condensing means uses a reflective material having a concave surface.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. A laser scribing apparatus comprising at least one condensing means, wherein a condensing point is between the condensing means and the substrate to be cut.     The laser scribing apparatus according to claim 18, wherein the condensing means is a transmissive material having a convex surface.     The laser scribing apparatus according to claim 18 or 19, wherein the condensing means is a reflective material made of a concave surface.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In a laser scribing method, a laser beam method comprising: at least one condensing means; and means for changing a distance between the condensing means and the substrate to be cut, and the beam shape on the substrate to be cut can be changed. .     The laser scribing method according to claim 21, wherein the power of the beam per unit area on the substrate to be cut, that is, the power density of the beam can be changed.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. A laser scribing apparatus, comprising: at least one condensing means; means for changing a distance between the condensing means and the substrate to be cut; and a laser having a function capable of changing a beam shape on the substrate to be cut Beam device.     The laser scribing apparatus according to claim 23, wherein the power of the beam per unit area on the substrate to be cut, that is, the power density of the beam can be changed.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In the laser scribing method, a scribing line initial crack generating means, a means for changing the distance between the initial crack generating means and the substrate to be cut, and a means for measuring the distance are provided. A laser scribing method characterized by measuring.     Prior to the cleaving step for cleaving the substrate to be cut, a scribe line from the start end to the end of the planned cut line is formed by moving the laser light relative to the cut substrate along the planned cut line of the cut substrate. In the laser scribing apparatus, an initial crack generating means for the scribe line, and a means for changing a distance between the initial crack generating means and the substrate to be cut. And a means for measuring the distance, wherein the distance can be measured before the initial crack is generated.     A laser scribing method according to any one of claims 1 to 4, claim 9 to claim 11, claim 15 to claim 17, claim 21 to claim 22, and claim 25. A cleaved substrate obtained by cleaving a cleaved substrate that has been subjected to a scribing process.     A laser scribing apparatus according to any one of claims 5 to 8, claim 12 to claim 14, claim 18 to claim 20, claim 23 to claim 24, and claim 26. A cleaved substrate obtained by cleaving a cleaved substrate that has been subjected to a scribing process.

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