JP2007283319A - Laser scribing method, electrooptical device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser scribing method for easily inspecting the formation state of a reformed layer from the outside of a substrate, and to provide an electrooptical device and electronic equipment. <P>SOLUTION: The laser scribing method includes: a substrate manufacturing process (fig.(a)) for forming an inspection mark M1 whose mode varies by the irradiation of a laser beam 44, on the planned cutting lines Dx, Dy provided to a position to be cut for each of a plurality of liquid crystal display panels 20 formed on a first substrate 11, and at least on one side of the first substrate; a laser irradiation process (fig.(b)) for forming a reformed layer R inside the first substrate 11 by irradiating it with the laser beam 44 so that the laser beam 44 irradiates the surface of the first substrate 11 on which at least the inspection mark M1 is formed along the planned cutting lines Dx, Dy; and an inspection process (fig.(c)) for inspecting change in the mode of the inspection mark M1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a laser scribing method, an electro-optical device, and an electronic apparatus.

  Conventionally, a laser scribing method for cutting a substrate by irradiating a laser beam is known. In this method, a laser beam is condensed inside the substrate, a modified layer is formed at the condensing point, and an external force is applied to the substrate to cut the substrate starting from the modified layer. It is. As a method for forming the modified layer, for example, as shown in Patent Document 1, the position of the condensing point is changed in the thickness direction of the substrate with respect to the planned cutting line provided on the substrate, and a plurality of laser beam scans are performed. A method is known in which a plurality of modified layers are formed in a stacked manner.

JP 2002-205180 A

  However, since the modified layer is formed almost inside the substrate, it was not possible to easily know whether the modified layer was formed on the substrate from the outside of the substrate. Further, if the substrate is cut without the modified layer being sufficiently formed, the substrate may be damaged due to chipping or the like.

  The present invention has been made to solve the above-described problem, and provides a laser scribing method, an electro-optical device, and an electronic apparatus that can easily inspect the formation state of a modified layer from the outside of a substrate. It is in.

  In order to solve the above-described problem, in the present invention, a laser beam is formed on a planned cutting line provided at a position to be cut for each of a plurality of functional units formed on a substrate, and is applied to at least one surface of the substrate. The substrate manufacturing process for forming a thin film whose aspect changes due to the irradiation, and the laser beam is directed toward the substrate so that at least the surface portion of the substrate on which the thin film is formed is irradiated along the planned cutting line. The gist of the invention includes a laser irradiation step of irradiating and forming a modified layer inside the substrate, and an inspection step of inspecting a change in form caused by laser light irradiation of the thin film.

  According to the laser scribing method of the present invention, when the thin film is formed on the surface of the substrate and is irradiated with laser light, the thin film is changed. Therefore, by inspecting the presence or absence of a thin film mode, the formation state of the modified layer can be easily inspected as an alternative.

  In the substrate manufacturing process of the laser scribing method of the present invention, a thin film may be formed on the peripheral edge of the substrate in a region other than the region where the functional part of the substrate is formed.

  According to this, since the thin film is formed at the peripheral portion of the substrate, the substrate can be manufactured without being limited to the layout of the functional portion of the substrate.

  The inspection process of the laser scribing method of the present invention may be performed at the same time as the laser irradiation process.

  According to this, in the laser irradiation process, it is possible to improve the working efficiency and to find defects at an early stage by inspecting the change in the mode of the thin film.

  In the substrate manufacturing process of the laser scribing method of the present invention, the thin film on which the laser mark is formed may be formed by laser light irradiation, and in the inspection process, the change in the mode of the thin film due to the laser mark may be inspected.

  According to this, when laser light is irradiated, laser marks are formed on the thin film. Therefore, the formation state of the modified layer can be easily inspected by confirming whether a laser mark is formed on the thin film after the laser light irradiation.

  In the substrate manufacturing process of the laser scribing method of the present invention, a thin film may be formed with a conductive material, and in the inspection process, a change in electrical characteristics between the thin films with the laser mark interposed therebetween may be inspected.

  According to this, since the thin film is formed of a conductive material, when the laser beam is irradiated along the planned cutting line and a laser mark is formed on the thin film, the electrical resistance between the thin films sandwiching the planned cutting line The value changes. Therefore, it is possible to easily inspect the formation state of the modified layer by inspecting the change in the electrical resistance value.

  In the substrate manufacturing process of the laser scribing method of the present invention, a thin film is formed for each line to be cut, and a pattern for electrically connecting a plurality of formed thin films is formed. In the inspection process, the thin film partitioned by laser marks Changes in electrical characteristics may be inspected.

  According to this, since the thin film electrically connected to each other is formed for each planned cutting line provided on the substrate, the laser beam is irradiated along the planned cutting line, and a laser mark is formed on the thin film. The electrical resistance value between the thin films changes. Therefore, the efficiency of the inspection work can be improved by collectively inspecting the change in the electrical resistance value of the substrates.

  The inspection process of the laser scribing method of the present invention includes a determination process for determining whether or not there is a change in the state of the thin film. When it is determined in the determination process that the aspect of the thin film is changed, an external force is applied to the substrate. It may have a substrate cutting process which cuts and divides for every functional part.

  According to this, since the substrate that is determined to have a change in the mode of the thin film, that is, the substrate on which the modified layer is formed by laser irradiation, is cut, occurrence of chipping can be suppressed when cut. .

  In the determination step of the laser scribing method of the present invention, when it is determined that there is no change in the aspect of the thin film, the substrate may be suspended or the laser irradiation step may be performed again.

  According to this, a non-defective substrate can be obtained by holding a substrate that has been determined to have no change in the form of the thin film, that is, a substrate that has a high possibility that the laser irradiation is insufficient and the modified layer is not properly formed. Can be reliably identified. Moreover, it can repair by irradiating the board | substrate determined that there is no change of the aspect of a thin film with a laser.

  The gist of the electro-optical device of the present invention is that it is divided by the laser scribing method described above.

  According to the electro-optical device according to the present invention, since the division is performed based on the change in the aspect of the thin film, a high-quality electro-optical device without chipping or the like can be provided.

  The gist of the electronic apparatus of the present invention is that the above-described electro-optical device is mounted.

  According to this, an electronic device with high quality can be provided.

  Hereinafter, first and second embodiments embodying the present invention will be described with reference to the drawings.

[First embodiment]
First, the first embodiment will be described.

(Mother board configuration)
First, the configuration of the mother board will be described. FIG. 1 shows a configuration of a mother substrate, FIG. 1 (a) shows a plan view, and FIG. 1 (b) shows a schematic cross-sectional view taken along line AA of FIG. 1 (a).

  1A and 1B, a mother substrate 10 has a wafer shape, and a first substrate 11 and a second substrate 12 are bonded to each other, and includes a liquid crystal display panel 20 as a plurality of functional units. . One liquid crystal display panel 20 is a position to be cut for each liquid crystal display panel 20, and is cut along the scheduled cutting lines Dx and Dy provided on the first substrate 11 and divided from the mother substrate 10. .

  The inspection mark M1 as a thin film is formed on the planned cutting lines Dx and Dy on the peripheral edge of the first substrate 11 in a region other than the region where the liquid crystal display panel 20 is formed on the mother substrate 10. The inspection mark M1 is a thin film whose aspect changes when irradiated with laser light, and is formed corresponding to each of the scheduled cutting lines Dx and Dy.

(Structure of functional part)
Next, the configuration of the functional unit will be described. 2 shows a configuration of a liquid crystal display panel as a functional unit, FIG. 2 (a) shows a plan view, and FIG. 2 (b) shows a schematic cross-sectional view taken along line BB in FIG. 2 (a). Show.

  2, the liquid crystal display panel 20 includes a first substrate 11 having a thin film transistor (TFT) element 23 and a second substrate 12 having a counter electrode 26, as shown in FIGS. 2 (a) and 2 (b). And a liquid crystal material 25 filled in a gap between the substrates 11 and 12 bonded by the sealing material 24. The first substrate 11 protrudes in a frame shape that is slightly larger than the second substrate 12, and a terminal portion 11 a as a pattern is formed on the surface of the protruding first substrate 11.

  The first substrate 11 uses a quartz glass substrate having a thickness of about 1.2 mm, and has a pixel electrode (not shown) constituting a pixel on its surface and a TFT in which one of the three terminals is connected to the pixel electrode. An element 23 is formed. The remaining two terminals of the TFT element 23 are connected to a data line (not shown) and a scanning line (not shown) which are arranged in a grid in a state of being insulated from each other so as to surround the pixel electrode. The data line is drawn out in the Y-axis direction and connected to a data line driving circuit unit 29 formed in the terminal unit 11a. The scanning lines are drawn in the X-axis direction and are individually connected to two scanning line driving circuit units 33 formed in the left and right frame regions. The input side wirings of the data line driving circuit unit 29 and the scanning line driving circuit unit 33 are connected to the mounting terminals 31 arranged along the terminal unit 11a. In the frame region opposite to the terminal portion 11a, a wiring 32 that connects the two scanning line driving circuit portions 33 is provided.

  The second substrate 12 uses a transparent glass substrate having a thickness of approximately 1.2 to 1.1 mm, and is provided with a counter electrode 26 as a common electrode. The counter electrode 26 is electrically connected to the wiring provided on the first substrate 11 side via the vertical conduction parts 34 provided at the four corners of the second substrate 12, and the wiring is also a mounting terminal provided in the terminal portion 11a. 31 is connected.

  Alignment films 27 and 28 are formed on the surface of the first substrate 11 and the surface of the second substrate 12 facing the liquid crystal material 25, respectively.

  In the liquid crystal display panel 20, a relay substrate that is electrically connected to an external drive circuit is connected to the mounting terminal 31. An input signal from the external drive circuit is input to each data line drive circuit unit 29 and the scan line drive circuit unit 33, whereby the TFT element 23 is switched for each pixel electrode, and the pixel electrode and the counter electrode 26 are switched. In the meantime, a drive voltage is applied to display.

(Configuration of laser irradiation device)
Next, a description will be given of the configuration of a laser irradiation apparatus for irradiating a laser beam along the planned cutting lines Dx and Dy provided on the mother substrate 10 and forming a modified layer in a portion irradiated with the laser beam. To do.

  FIG. 3 is a schematic diagram showing the configuration of the laser irradiation apparatus. In FIG. 3, a laser irradiation device 40 includes a laser light source 41 that emits a pulsed laser beam, a dichroic mirror 42 that reflects the emitted pulsed laser beam, and a collection unit that collects the reflected pulsed laser beam. And an optical lens 43. Further, a stage 47 on which the substrate 10 is placed and an X-axis slide part 48 and a Y-axis slide part 51 as moving means for moving the stage 47 in the X and Y axis directions with respect to the condenser lens 43 are provided. . Further, a Z-axis slide mechanism 54 as an adjusting means for adjusting the position of the condensing point of the pulse laser beam by changing the position of the condensing lens 43 in the Z-axis direction with respect to the substrate 10 placed on the stage 47 is provided. I have. Further, an imaging device 55 is provided on the opposite side of the condenser lens 43 with the dichroic mirror 42 interposed therebetween, and the thin film formed on the surface of the first substrate 11 can be imaged.

  The laser irradiation device 40 includes a main computer 60 that controls each of the above components. The main computer 60 includes an image processing unit 61 that processes image information captured by the image capturing device 55 in addition to a CPU and various memories. is doing. The imaging device 55 incorporates a coaxial incident light source and a CCD (solid-state imaging device). Visible light emitted from the coaxial incident light source passes through the condenser lens 43 and is focused.

  Connected to the main computer 60 are an input unit 63 for inputting data of various processing conditions used during laser processing and a display unit 64 for displaying various information during laser processing. A laser control unit 66 that controls the output, pulse width, and pulse period of the laser light source 41 and a lens control unit 67 that drives the Z-axis slide mechanism 54 to control the position of the condenser lens 43 in the Z-axis direction. It is connected. Further, a stage control unit 70 is connected to drive a servo motor (not shown) that moves the X-axis slide unit 48 and the Y-axis slide unit 51 along rails 68 and 69, respectively.

  The Z-axis slide mechanism 54 that moves the condenser lens 43 in the Z-axis direction has a built-in position sensor that can detect the movement distance, and the lens control unit 67 detects the output of the position sensor and collects the light. The position of the lens 43 in the Z-axis direction can be controlled. Therefore, the thickness of the substrate 10 can be measured by moving the condenser lens 43 in the Z-axis direction so that the visible light emitted from the coaxial incident light source of the imaging device 55 is in focus with the surface of the substrate 10. It is.

  The laser light source 41 is a so-called femtosecond laser that emits laser light using, for example, titanium sapphire as a solid light source with a pulse width of femtoseconds. In this case, the pulsed laser light has wavelength dispersion characteristics, the center wavelength is 800 nm, and the half width is about 20 nm. The pulse width is about 300 fs (femtosecond), the pulse period is 1 kHz, and the output is about 700 mW.

  In this case, the condenser lens 43 is an objective lens having a magnification of 100 times, a numerical aperture (NA) of 0.8, and a WD (Working Distance) of 3 mm. The condenser lens 43 is supported by a slide arm 54 a extending from the Z-axis slide mechanism 54.

  In this embodiment, the stage 47 is supported by the Y-axis slide unit 51, but is supported by the X-axis slide unit 48 by reversing the positional relationship between the X-axis slide unit 48 and the Y-axis slide unit 51. It is good also as a form. Moreover, it is preferable to support the stage 47 on the Y-axis slide part 51 via a θ table (not shown). According to this, it is possible to make the board | substrate 10 into a more perpendicular | vertical state with respect to the optical axis 41a.

(Laser scribing method)
Next, a laser scribing method will be described. FIG. 4 is a flowchart showing the laser scribing method in the first embodiment. FIG. 5 is a schematic diagram showing a laser scribing method in the first embodiment.

  In step S1 of FIG. 4, the substrate is manufactured. In the substrate manufacturing process, as shown in FIG. 5A, the TFT elements 23 and the like are formed on the first substrate 11, and the sealing material 24 is formed on the surface of the first substrate 11. A liquid crystal material 25 is applied to the formed region. On the other hand, the common electrode 26 and the like are formed on the second substrate 12. Then, both the substrates 11 and 12 are arranged to face each other, and both the substrates 11 and 12 are bonded by the adhesive force of the sealing material 24. Further, the inspection mark M1 is formed on the surface on which the TFT element 23 of the first substrate 11 is formed on the cutting planned lines Dx and Dy. The inspection mark M1 is an area other than the area where the liquid crystal panel 20 is formed, and is formed on the peripheral edge of the first substrate 11 (see FIG. 1).

  The inspection mark M1 is formed of a material whose aspect changes by laser light irradiation. For example, a polyimide resin or an epoxy resin can be used. Further, as a method of forming the inspection mark M1, it can be formed using, for example, an ink jet method, a printing method, a photolithography method, or the like. Note that the inspection mark M1 is not necessarily formed after the first substrate 11 and the second substrate 12 are bonded, and may be formed in the process of forming the first substrate 11.

  In step S <b> 2 of FIG. 4, laser irradiation is performed toward the first substrate 11. In the laser irradiation step, as shown in FIG. 5B, the laser beam 44 is irradiated toward the first surface S1 on which the TFT elements 23 and the like of the first substrate 11 are formed using the laser irradiation device 40. To do. The laser beam 44 has a condensing point set in the vicinity of the second surface S2 which is the opposite surface of the first surface S1 of the first substrate 11, is parallel to the second surface S2, and is a line to be cut. Scan while irradiating along Dx and Dy. Thereafter, the position of the condensing point is moved in the Z-axis direction so that the position of the condensing point approaches the first surface S1, and scanning is performed along the planned cutting lines Dx and Dy while irradiating the laser beam 44. Then, the position of the condensing point is further moved in the Z-axis direction, and scanning is performed a plurality of times until reaching the first surface S1 on which the inspection mark M1 is formed, so that the modification along the scheduled cutting lines Dx and Dy is achieved. Layer R is formed.

  In the irradiation process, when the laser beam 44 is irradiated to the first surface S1, a laser mark H1 is formed on the inspection mark M1, as shown in FIG. 5B. The laser mark H1 is formed at a place where the laser beam 44 is scanned, and the mode of the inspection mark M1 in the region where the laser mark H1 is formed and the region other than the laser mark H1 are different depending on whether or not the laser beam 44 is irradiated. Yes.

  In step S3 of FIG. 4, the inspection mark M1 is inspected. In the inspection step, as shown in FIG. 5C, a change in the aspect of the inspection mark M1 is inspected. Specifically, the inspection mark M1 is imaged after the stage 47 is relatively moved so that the imaging device 55 is positioned above the inspection mark M1. The imaged information data is transmitted to the main computer 60 and subjected to image processing by the image processing unit 61. The imaging of the inspection mark M1 in the inspection process can be performed at the same time as the irradiation of the laser beam 44.

  In step S4 in FIG. 4, a change in the aspect of the inspection mark M1 is determined. In the determination step, it is determined whether or not the aspect of the inspection mark M1 has changed due to the formation of the laser mark H1, based on preset image data serving as a reference.

  In step S5 of FIG. 4, the mother substrate 10 is cut if YES in step S4. In the cutting step, an external force is applied to the mother substrate 10 as shown in FIG. When an external force is applied, stress is generated in the modified layer R formed inside the first substrate 11, and the first substrate 11 is cut along the modified layer R. As shown in FIG. The liquid crystal display panel 20 is divided.

  In step S6 of FIG. 4, in the case of NO in step S4, the processing of the mother substrate 10 is temporarily suspended, and is identified from the mother substrate 10 that has been determined to have a change in the aspect of the inspection mark M1. Since there is a high possibility that the laser beam 44 is not properly irradiated on the mother substrate 10 that has been determined that the inspection mark M1 has no change in form, problems such as chipping occur when the mother substrate 10 is cut in this state. Because there is a fear. The suspended mother board 10 can then be shifted to laser irradiation in step S2 in order to repair in consideration of productivity and reliability.

(Configuration of electro-optical device)
The configuration of the liquid crystal display panel 20 as the electro-optical device is the same as the configuration of the liquid crystal display panel 20 as the functional unit described above, and thus the description thereof is omitted (see FIG. 2).

(Configuration of electronic equipment)
Next, the configuration of the electronic device will be described. FIG. 6 is a perspective view showing a configuration of a projector as an electronic apparatus. In FIG. 6, the liquid crystal display panel 20 is mounted on the optical system constituting the projector 80.

  Therefore, according to the first embodiment, there are the following effects.

  (1) When the inspection mark M1 formed on the first surface S1 of the first substrate 11 on the scheduled cutting lines Dx and Dy of the first substrate 11 is irradiated with the laser beam 44, the inspection mark M1 is applied to the inspection mark M1. A laser mark H1 is formed. And the inspection mark M1 is imaged by the imaging device 55, and the presence or absence of the laser mark H1 is inspected. Therefore, by inspecting the presence or absence of the laser mark H1 of the inspection mark M1, as an alternative to the inspection of the formation state of the modified layer formed inside the first substrate 11 by irradiation of the laser beam 44, the first substrate 11 It can be easily inspected from the outside.

  (2) The inspection mark M1 is a region other than the region where the liquid crystal display panel 20 is formed, and is formed on the peripheral portion of the first substrate 11, so that the design layout is not limited and the first substrate 11 It can be used effectively.

  (3) Since it is determined whether or not the laser mark H1 is formed on the inspection mark M1, the mother substrate 10 to be cut and the mother substrate 10 to be held are identified, thereby suppressing the occurrence of defective products. it can.

[Second Embodiment]
Next, a second embodiment will be described. Note that the configuration of the liquid crystal display panel as the functional unit, the configuration of the laser irradiation device, the configuration of the electro-optical device, and the configuration of the electronic apparatus are the same as those in the first embodiment, and thus description thereof is omitted.

(Mother board configuration)
First, the configuration of the mother board will be described. 7 shows the configuration of the mother substrate, FIG. 1 (a) shows a plan view, and FIG. 7 (b) shows a schematic cross-sectional view taken along line AA of FIG.

  7A and 7B, the mother substrate 10 has a wafer shape, and the first substrate 11 and the second substrate 12 are bonded to each other, and is configured by a liquid crystal display panel 20 as a plurality of functional units. . One liquid crystal display panel 20 is a position to be cut for each liquid crystal display panel 20, and is cut along the scheduled cutting lines Dx and Dy provided on the first substrate 11 and divided from the mother substrate 10. .

  In the region other than the liquid crystal display panel 20 formed on the mother substrate 10, the inspection mark M <b> 2 as a thin film is formed on the scheduled cutting lines Dx and Dy on the peripheral edge of the first substrate 11. The inspection mark M2 is a thin film whose aspect changes when irradiated with laser light, and the inspection marks M2 formed on the respective scheduled cutting lines Dx and Dy are connected to each other and formed in a continuous shape.

(Laser scribing method)
Next, a laser scribing method will be described. FIG. 8 is a flowchart showing a laser scribing method in the second embodiment. FIG. 9 is a schematic diagram showing a laser scribing method in the second embodiment.

  In step S1 of FIG. 8, substrate manufacture is performed. In the substrate manufacturing process, as shown in FIG. 9A, the TFT elements 23 and the like are formed on the first substrate 11 and the sealing material 24 is formed on the surface of the first substrate 11. A liquid crystal material 25 is applied to the formed region. On the other hand, the common electrode 26 and the like are formed on the second substrate 12. Then, both the substrates 11 and 12 are arranged to face each other, and both the substrates 11 and 12 are bonded by the adhesive force of the sealing material 24. Further, the inspection mark M2 is formed on the surface on which the TFT element 23 of the first substrate 11 is formed on the cutting planned lines Dx and Dy. The inspection mark M2 is an area other than the area where the liquid crystal display panel 20 is formed, and is formed continuously to the peripheral edge of the first substrate 11 (see FIG. 7).

  The inspection mark M2 is formed of a conductive material while changing its form by irradiation with laser light. In addition, as a method for forming the inspection mark M2, for example, an inkjet method, a printing method, a photolithography method, or the like is used. Note that the inspection mark M2 is not necessarily formed after the first substrate 11 and the second substrate 12 are bonded, and may be formed in the process of forming the first substrate 11.

  In step S <b> 2 of FIG. 8, laser irradiation is performed toward the first substrate 11. In the laser irradiation step, as shown in FIG. 9B, a laser beam 44 is irradiated toward the first surface S1 on which the TFT elements 23 and the like of the first substrate 11 are formed using a laser irradiation apparatus 40. To do. The laser beam 44 has a condensing point set in the vicinity of the second surface S2 which is the opposite surface of the first surface S1 of the first substrate 11, is parallel to the second surface S2, and is a line to be cut. Scan while irradiating along Dx and Dy. Thereafter, the position of the condensing point is moved in the Z-axis direction so that the position of the condensing point approaches the first surface S1, and scanning is performed along the planned cutting lines Dx and Dy while irradiating the laser beam 44. Then, the position of the condensing point is further moved in the Z-axis direction, and scanning is performed a plurality of times until reaching the first surface S1 on which the inspection mark M2 is formed, thereby improving along the scheduled cutting lines Dx and Dy. Layer R is formed.

  In the irradiation step, when the laser beam 44 is irradiated to the first surface S1, a laser mark H2 is formed on the inspection mark M2, as shown in FIG. 9B. The laser mark H2 is formed at a position where the laser beam 44 is scanned, and the mode of the inspection mark M2 in the region where the laser mark H2 is formed and the region other than the laser mark H2 are different depending on whether or not the laser beam 44 is irradiated. Yes.

  In step S3 of FIG. 8, the electrical characteristics of the inspection mark M2 are inspected. In the inspection step, as shown in FIG. 9C, the electrical characteristics between the inspection mark M2a and the inspection mark M2b sandwiching the laser mark H2 of the inspection mark M2 are inspected. For example, one tester terminal 78a of the tester 78 is connected to the inspection mark M2a, the other tester terminal 78b is connected to the inspection mark M2b, and the continuity between both tester terminals 78a and 78b is inspected. Note that the inspection of the electrical characteristics can be performed at the same time as the irradiation of the laser beam 44.

  In step S4 of FIG. 8, it is determined whether or not there is a change in electrical characteristics between the tester terminals 78a and 78b in the inspection mark M2. In the determination step, the determination is made based on electrical characteristic data serving as a reference set in advance.

  In step S5 in FIG. 8, the mother substrate 10 is cut if YES in step S4. In the cutting step, an external force is applied to the mother substrate 10 as shown in FIG. When an external force is applied, stress is generated in the modified layer R formed inside the first substrate 11, and the first substrate 11 is cut along the modified layer R, as shown in FIG. The liquid crystal display panel 20 is divided.

  In step S6 of FIG. 8, in the case of NO in step S4, the processing of the mother substrate 10 is temporarily suspended, and is identified from the mother substrate 10 that has been determined to have a change in the aspect of the inspection mark M2. Since there is a high possibility that the laser beam 44 is not properly irradiated on the mother substrate 10 that is determined to have no change in the aspect of the inspection mark M2, if the mother substrate 10 is cut in this state, problems such as chipping occur. Because there is a fear. The suspended mother board 10 can then be shifted to laser irradiation in step S2 in order to repair in consideration of productivity, reliability, and the like.

  Therefore, according to said 2nd Embodiment, in addition to the effect in 1st Embodiment, there exists an effect shown below.

  When the inspection mark M2 formed on the first cut surface D1 and Dy of the first substrate 11 and formed on the first surface S1 of the first substrate 11 using the conductive material is irradiated with the laser beam 44, the inspection is performed. A laser mark H2 is formed on the mark M2. Then, the inspection mark M2 is inspected for continuity between the inspection marks M2a and M2b using the tester 78 with the laser mark H2 of the inspection mark M2 interposed therebetween. Therefore, by conducting the continuity test, it is possible to easily inspect from the outside of the first substrate 11 as an alternative to the inspection of the formation state of the modified layer R formed inside the first substrate 11 by irradiation with the laser beam 44. .

  The present invention is not limited to the above-described embodiment, and the following modifications are given.

  (Modification 1) In the inspection process of the first embodiment, the inspection mark M1 is imaged using the imaging device 55, but the present invention is not limited to this. For example, the inspection mark M1 may be inspected visually. Even in this case, the presence or absence of the laser mark H1 of the inspection mark M1 can be inspected.

  (Modification 2) In the inspection process of the first embodiment, the inspection mark M1 is imaged using the imaging device 55, but the present invention is not limited to this. For example, the surface of the inspection mark M1 may be measured using a surface roughness meter. Even in this way, the presence or absence of the laser mark H1 can be inspected by the roughness of the surface of the inspection mark M1.

  (Modification 3) In the substrate manufacturing process of the first embodiment, the inspection mark M1 is formed on each of the scheduled cutting lines Dx and Dy, but the present invention is not limited to this. For example, it may be formed continuously like the shape of the inspection mark M2 of the second embodiment. Even in this case, the presence or absence of the laser mark H1 of the inspection mark M1 can be inspected.

  (Modification 4) In the first and second embodiments, the inspection marks M1 and M2 are formed only on one surface of the first substrate 11, but the present invention is not limited to this. For example, the inspection marks M1 and M2 may be formed on the other surface, and the inspection marks M1 and M2 formed on both surfaces of the first substrate 11 may be inspected. In this way, since the inspection accuracy is improved, a high quality liquid crystal display panel 20 can be provided.

  (Modification 5) In the first and second embodiments, the inspection marks M1 and M2 are formed on the respective scheduled cutting lines Dx and Dy. However, the present invention is not limited to this. The inspection marks M1 and M2 may be formed only on the specific cutting lines Dx and Dy. In this way, the number of steps in the substrate manufacturing process can be reduced.

  (Modification 6) In the inspection process of the first and second embodiments, all inspection marks M1 and M2 are inspected, but the present invention is not limited to this. For example, only the inspection marks M1, M2 formed at specific locations may be inspected. In this way, man-hours in the inspection process can be reduced.

The structure of the mother board | substrate in 1st Embodiment is shown, (a) is a top view, (b) is sectional drawing. 2 shows a configuration of a functional unit and a liquid crystal display panel as an electro-optical device, in which (a) is a plan view and (b) is a cross-sectional view. The schematic diagram which shows the structure of a laser irradiation apparatus. The flowchart figure which shows the laser scribing method in 1st Embodiment. The schematic diagram which shows the laser scribing method in 1st Embodiment. The perspective view which shows the structure of the projector as an electronic device. The structure of the mother board | substrate in 2nd Embodiment is shown, (a) is a top view, (b) is sectional drawing. The flowchart figure which shows the laser scribing method in 2nd Embodiment. The schematic diagram which shows the laser scribing method in 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Mother board | substrate, 11 ... 1st board | substrate, 12 ... 2nd board | substrate, 20 ... Liquid crystal display panel as a function part and an electro-optical device, 40 ... Laser irradiation apparatus, 44 ... Laser beam, 55 ... Imaging apparatus, 60 ... Main Computer 61: Image processing unit 78: Tester 78a, 78b Tester terminal 80: Projector as electronic device S1: First surface S2: Second surface M1, M2, M2a, M2b: Inspection Marks, H1, H2 ... laser marks, R ... modified layer, Dx, Dy ... lines to be cut.

Claims (10)

A substrate on a line to be cut provided at a position to be cut for each of a plurality of functional parts formed on the substrate, wherein a thin film whose form is changed by laser light irradiation is formed on at least one surface of the substrate Manufacturing process,
Irradiate the laser beam toward the substrate and modify the inside of the substrate so that at least the surface portion of the substrate on which the thin film is formed is irradiated along the planned cutting line. A laser irradiation step of forming a layer;
An inspection step of inspecting a change in an aspect of the thin film due to the irradiation of the laser light. The laser scribing method according to claim 1, wherein
In the substrate manufacturing process, the thin film is formed in a region other than a region where the functional portion of the substrate is formed, and on a peripheral portion of the substrate. The laser scribing method according to claim 1 or 2,
The laser scribing method, wherein the inspection step is performed at the same time as the laser irradiation step. In the laser scribing method according to any one of claims 1 to 3,
In the substrate manufacturing process, the thin film on which laser marks are formed by irradiation with the laser light is formed,
In the inspection step, a change in the form of the thin film due to the laser mark is inspected. In the laser scribing method according to any one of claims 1 to 4,
In the substrate manufacturing process, the thin film is formed of a conductive material,
In the inspection step, a change in electrical characteristics between the thin films sandwiching the laser mark is inspected. In the laser scribing method according to any one of claims 1 to 5,
In the substrate manufacturing process, the thin film is formed for each of the scheduled cutting lines, and a pattern for electrically connecting a plurality of the thin films formed is formed.
In the inspection step, a change in electrical characteristics between the thin films defined by the laser marks is inspected, and the laser scribing method is characterized in that: In the laser scribing method according to any one of claims 1 to 6,
The inspection step includes a determination step of determining whether there is a change in the aspect of the thin film,
A laser scribing method comprising: a substrate cutting step in which, in the determination step, when it is determined that there is a change in an aspect of the thin film, the substrate is cut by applying an external force to the substrate, and is divided for each functional unit . In the laser scribing method according to any one of claims 1 to 7,
A laser scribing method comprising: holding the substrate or performing the laser irradiation step again when it is determined in the determination step that there is no change in the form of the thin film.   An electro-optical device as a functional unit, which is divided by the laser scribing method according to claim 1.   An electronic apparatus comprising the electro-optical device according to claim 9.