JP2007190596A - Method for manufacturing base body, flexible circuit substrate, electrooptical device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a base body by which acceptable number is improved while keeping the quality of divided pieces even when the material of the base body is a resin material in a method for cutting and dividing the base body by using a laser beam. <P>SOLUTION: The method for manufacturing a substrate 4 as the base body is a method for manufacturing the substrate 4 composed of a resin material and provided with a stage where a changed quality part 7 of the material is formed by irradiating the base body 4 with the laser beam 5 and a stage where the divided pieces Q are formed by adding stress F to this base body 4 from the outside. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a substrate manufacturing method, a flexible circuit board, an electro-optical device, and an electronic apparatus.

  In recent years, there has been an increasing need for flexibility in display devices and the like, and there is an increasing tendency to use resin materials such as films for substrates. Moreover, it has been a long time to use a resin material for the flexible circuit board. In this case, a high-quality and high-precision manufacturing method is required as a method of cutting a flexible circuit board into a single piece from a mother board or reel tape. Therefore, as a method of cutting and dividing a substrate made of a resin material such as a synthetic resin film or a crosslinked resin sheet, there is a method of cutting and dividing by irradiating a laser beam.

  For example, as disclosed in Patent Document 1, in a method of cutting / dividing a synthetic resin film substrate, a method of forming a divided piece by cutting / dividing by irradiating a laser beam along the planned cutting line Has been proposed. Further, as disclosed in, for example, Patent Document 2, a similar proposal has been made for a method of cutting and dividing a cross-linked resin sheet substrate to form divided pieces.

Japanese Patent Laid-Open No. 5-69169 JP-A-10-151676

  However, in the methods of Patent Document 1 and Patent Document 2, since a method of dividing and cutting a substrate such as a synthetic resin film or a crosslinked resin sheet by irradiating a laser beam, a certain cutting width is required to cut the substrate. (Cutting allowance) was necessary. For this reason, when a large cutting width is required, the number of pieces to be taken out when a piece is taken out from a single substrate is reduced, and there is a limit to increasing the number of pieces taken up. Furthermore, in the method of Patent Document 2, since the substrate is cut by irradiating the substrate with laser light generated by exciting a carbon dioxide laser, processing debris called debris may occur. Then, the generated processing scrap adheres to the vicinity of the cut portion of the split piece, and the quality deteriorates or the processing scrap adheres to and accumulates on the laser processing apparatus. Recovery) was necessary.

  An object of the present invention is a method of cutting and dividing a substrate using a laser beam, which can improve the number of pieces while maintaining the quality of divided pieces even if the substrate material is a resin material. It is to provide a manufacturing method.

  The substrate manufacturing method of the present invention is a method for manufacturing a substrate made of a resin material, the step of irradiating the substrate with a laser beam to form a material-modified part, and applying stress to the substrate to divide the piece. And a step of forming the structure.

  According to the present invention, even if the substrate is a resin material, the material altered portion can be formed on the substrate by irradiating the substrate with laser light. Therefore, by applying stress to the base from the outside, the base is cut and divided along the material-affected portion, so that the divided pieces can be formed without requiring a cutting width. Therefore, the number of picks can be improved. In addition, since it is a manufacturing method in which foreign matter does not occur during cutting and division, it is possible to prevent quality deterioration due to foreign matter adhesion.

  In the method for manufacturing a substrate according to the present invention, the substrate is made of a material made of a resin material that is transparent to laser light. In the step of forming the material altered portion, the laser beam is applied to the substrate. It is desirable that the material altered portion is formed by condensing and irradiating with a condensing element.

  According to this invention, when the laser beam is condensed and irradiated on the substrate by the light condensing element, the substrate can absorb the laser beam because the substrate is a resin material that can transmit the laser beam. Thus, it is possible to easily form the material altered portion at a predetermined position of the substrate.

  In the method of manufacturing a substrate according to the present invention, in the step of forming the material altered portion, the laser beam is preferably a YAG laser, and the material altered portion is preferably formed by irradiating a fundamental wave of the YAG laser. .

  According to the present invention, when the fundamental wave of the YAG laser is irradiated onto the substrate, the fundamental wave of the YAG laser has a wavelength that is transparent to the resin material. The part can be formed easily.

  In the method of manufacturing a substrate according to the present invention, in the step of forming the material altered portion, the laser beam is branched into a plurality of beams by a diffractive optical element, and the plurality of beams are irradiated to form the material altered portion. It is desirable.

  According to the present invention, the laser beam is split into a plurality of beams by the diffractive optical element, so that the beams are split. Therefore, a plurality of material-affected portions can be formed on the base by irradiating the base with the split beams. .

  In the substrate manufacturing method of the present invention, in the step of forming the divided pieces, it is desirable that the divided pieces are formed by applying any one of bending stress and tensile stress to the substrate.

  According to the present invention, since the base can be cut and divided only by applying stress to the base, the divided pieces can be easily formed.

  The flexible circuit board of the present invention is formed using the above-described substrate manufacturing method.

  According to this invention, since it is formed efficiently, a cheaper flexible circuit board can be provided.

  An electro-optical device according to the present invention includes the flexible circuit board described above.

  According to the present invention, since a cheaper flexible circuit board is provided, a cheaper electro-optical device can be provided.

  An electronic apparatus according to the present invention includes the electro-optical device described above.

  According to the present invention, since a cheaper electro-optical device is provided, a cheaper electronic device can be provided.

Hereinafter, embodiments of the method for producing a substrate of the present invention will be described in detail with reference to the accompanying drawings. Before describing the characteristic manufacturing method of the present invention, a method for forming a substrate and a material altered portion will be described.
<Substrate>

The substrate that can be used in the present invention can use a resin material (mainly a polymer material) as its material. For example, various resin materials such as polyimide, pet, polycarbonate, and acrylic can be used. Further, a substrate in which a base film such as a semiconductor film, a metal film, a dielectric film, or an organic film is formed on the surface of a substrate using these resin materials may be used as the substrate. Here, polyimide not provided with a base film was used as the resin material.
<Formation method of material alteration part>

  A method for forming a material altered portion on a substrate by irradiating laser light will be described.

  FIG. 1 is an explanatory diagram for explaining a method for forming a material-affected portion as a modified layer by laser light.

  In FIG. 1, a laser beam 5 is condensed and irradiated inside a substrate 4 as a base, and the laser beam 5 is scanned in a scanning direction X (dividing direction). Since the laser beam 5 is condensed by the lens 6 as a condensing element, the laser beam 5 can be focused inside the substrate 4. When the laser beam 5 is scanned in the scanning direction X (division direction), the material-affected portion 7 can be formed inside the substrate 4. The moving speed of the laser beam 5 in the scanning direction X is 100 mm / sec. The thickness of the substrate 4 is about 200 μm.

  Further, since the amount of the material altered portion 7 as the modified layer can be several tens of μm only by scanning the laser beam 5 once, in order to form the material altered portion 7 in the entire depth direction of the substrate 4. Needs to scan the laser beam 5 several times in the scanning direction X (division direction). Then, each time the laser beam 5 is scanned, the focal position of the lens 6 as a condensing element is raised from the lower surface to the upper surface of the substrate 4. Here, the reason why the focal position of the laser beam 5 is raised from the lower surface to the upper surface of the substrate 4 is that the laser beam 5 is scattered by the previously formed material alteration portion 7, and the entire region in the depth direction of the substrate 4. This is to prevent the material altered portion 7 from being unable to be formed.

(Embodiment)
In the present embodiment, a manufacturing method is described in which a resin material base is irradiated with laser light to form a material-modified portion inside the base, and stress is applied from the outside to cut and split the base to form divided pieces. To do.

  FIG. 2 is a diagram showing a manufacturing method for cutting and dividing the base body in this embodiment to form divided pieces, and FIG. 2 (a) is a diagram showing a process of forming a material altered portion. (b) is a figure which shows the state which applies stress, The figure (c) is a figure which shows a division | segmentation piece.

  As shown in FIG. 2A, the material of the substrate 4 as a base is a resin material, which is polyimide.

  The laser light 5 is condensed by a lens 6 as a condensing element, and the laser light 5 condensed by the lens 6 as a condensing element is irradiated to the lower surface side of the substrate 4 so that the focal point is in focus. The irradiated laser beam 5 is arranged so that the focal position is aligned over the entire depth direction of the substrate 4. Then, the laser beam 5 is irradiated while gradually moving the condensing point to the upper surface side of the substrate 4. Then, by utilizing the phenomenon of multiphoton absorption, the material-modified part 7 as a modified layer is formed in the entire depth direction of the substrate 4.

The detailed conditions of the laser beam 5 are as follows. The laser light source used excites the semiconductor laser. Laser medium: Nd: YAG. Laser wavelength: 1064 nm. Laser light spot cross section: 3.14 × 10 ⁻⁸ cm ² . Oscillation form: Q switch pulse. Repeat frequency: 100 KHz. Pulse width: 30 ns. Output: 20 μJ / pulse. Laser light quality: TEM ₀₀ . Polarization characteristics: linearly polarized light (C). Condenser lens magnification: 50 times. NA: 0.55. Transmittance with respect to laser light wavelength: 60% (D). Movement speed: 100 mm / sec.

  The laser wavelength of the YAG laser used does not stick to 1064 nm, and for example, the second harmonic may be used. The laser wavelength of the second harmonic is 532 nm.

  As shown in FIG. 2B, stress F is applied to the substrate 4 from the upper surface side of the substrate 4. As a method of applying the stress F from the outside of the substrate 4, for example, bending or applying a shear stress to the substrate 4 along a planned cutting line. Further, thermal stress can be generated by giving a temperature difference to the substrate 4. In addition, when the thickness of the board | substrate 4 is thinner, the board | substrate 4 may break naturally along the material alteration part 7 by forming the material alteration part 7. FIG.

  As shown in FIG. 2C, the substrate 4 is divided to form divided pieces Q. When the stress F is applied from the outside to the substrate 4 having the material altered portion 7, the divided pieces Q can be easily formed.

  In addition, since the substrate 4 is cut and divided after the laser beam 5 is irradiated onto the substrate 4 to form the material alteration portion 7 along the planned cutting line of the substrate 4, chips are not generated during cutting. . For example, there is no processing debris called debris that occurs when cutting with a carbon dioxide laser. Then, since the laser beam 5 is condensed by the lens 6 as a condensing element and then irradiated to the substrate 4 to cut and divide, the cutting width necessary for division as when cutting with a carbon dioxide gas laser is required. do not do. Since the cutting width is not necessary, the number of division pieces Q taken from one substrate 4 can be increased. As a result, the material can be saved, so that productivity can be improved.

  FIG. 3 is a view showing a manufacturing method for forming a wiring board by cutting and dividing the tape-like board in the present embodiment.

  As shown in FIG. 3, the substrate 4 is roughly configured by a plurality of sprocket holes 12, a plurality of leads 20, a semiconductor chip 30, and the like. The substrate 4 is in the form of a tape, and a plurality of sprocket holes 12 are formed at the end thereof. The thickness of the substrate 4 is often determined by its material, but is not particularly limited.

  The substrate 4 has a plurality of leads 20, and the material of the leads 20 is copper (Cu), chrome (Cr), titanium (Ti), nickel (Ni), titanium tungsten (Ti-W), gold ( Any one of Au), aluminum (Al), nickel vanadium (NiV), and tungsten (W) may be laminated or formed in any one layer. For example, the lead 20 may be formed by sputtering or the like, or an additive method for forming the lead 20 by electroless plating may be applied.

  A plurality of semiconductor chips 30 are mounted on the substrate 4. An integrated circuit is formed on the semiconductor chip 30, and the planar shape of the semiconductor chip 30 is generally rectangular, but is not limited thereto.

  The configuration of the substrate 4 is as described above, and a manufacturing method for taking out the wiring substrate 10 from the substrate 4 will be described below.

  In FIG. 3, the material altered portion 7 is formed along the planned cutting line L of the substrate 4, and the substrate 4 is cut and divided by applying stress to the substrate 4 from the outside to obtain the wiring substrate 10. Here, the method for forming the material altered portion 7 along the planned cutting line L and the cutting / dividing method are based on the manufacturing method shown in FIG. Then, the wiring board 10 is obtained by cutting and dividing the board 4. The obtained wiring board 10 includes a plurality of leads 20 and a semiconductor chip 30.

  FIG. 4 is an explanatory diagram for explaining a method of transporting the tape-shaped substrate in the present embodiment.

  As shown in FIG. 4, reels R 1, R 2, R 3, R 4 are arranged at four locations, and these reels R 1, R 2, R 3, R 4 support the tape-like substrate 4. Then, the sprocket (not shown) is fitted to the sprocket hole 12 (see FIG. 3), and the tape-like substrate 4 can be conveyed in the direction of the arrow by reel-to-reel.

  Here, if the first wiring substrate 10 can be taken out from the substrate 4 by the method shown in FIGS. 2 and 3, the substrate 4 is transported in the direction of the arrow. Then, preparations for taking out the second wiring board 10 can be made. Next, when the second wiring board 10 can be taken out, the board 4 is transported in the direction of the arrow. And the preparation for taking out the 3rd wiring board 10 is completed. As described above, the wiring board 10 can be taken out from the board 4 by repeating the work of taking out the wiring board 10 a plurality of times.

  FIG. 5 is a diagram illustrating the electro-optical device according to the present embodiment.

  As shown in FIG. 5, a liquid crystal display device 100 as an electro-optical device is roughly configured by a wiring substrate 10 provided with a semiconductor chip 30 and a circuit substrate 101. The above-described wiring board 10 is electrically connected to the circuit board 101. The wiring substrate 10 is used in a liquid crystal display device 100 as an electro-optical device, and the liquid crystal display device 100 as an electro-optical device is, for example, a liquid crystal display device, a plasma display device, an electroluminescence display device, etc. It has optical substances (liquid crystal, discharge gas, luminescent material, etc.). Further, as other uses of the wiring board 10, it is suitably used as one of components constituting an inkjet head, a wristwatch, NOTE-PC, a PDA (Personal Digital Assistants), electronic paper, and the like.

  FIG. 6 is a diagram illustrating an electronic apparatus according to the present embodiment.

  As shown in FIG. 6, a mobile phone 200 as an electronic apparatus according to the present embodiment includes the above-described liquid crystal display device 100 as a display unit. The mobile phone 200 includes a display unit 201. As described above, the mobile phone 200 as an electronic apparatus according to the present invention can include the liquid crystal display device 100 as an electro-optical device that can be easily cut and divided. Mobile phone 200 can be provided. The electronic device is not particular about the mobile phone 200. For example, a portable information device called a printer, a wristwatch, a NOTE-PC, a PDA, and an electronic paper, a portable terminal device, a personal computer, a word processor, a digital still camera, It can be suitably used as an image display means for a vehicle-mounted monitor, a monitor direct-view digital video recorder, a car navigation device, an electronic notebook, a workstation, a video phone, a POS terminal, and the like. By doing so, the use of the liquid crystal display device 100 as an electro-optical device is expanded, and various electronic devices can be provided.

  In the embodiment as described above, the following effects can be obtained.

(1) Even if the substrate 4 as a base is a resin material, the material-modified part 7 can be formed on the substrate 4 by irradiating the substrate 4 with the laser beam 5. Therefore, by applying the stress F to the substrate 4 from the outside, the substrate 4 can be cut / divided along the material altered portion 7, so that the divided pieces Q can be formed without requiring a cutting width. If the cutting width is eliminated, the number of cuts can be improved. In addition, since it is a manufacturing method in which foreign matter does not occur during cutting and division, it is possible to prevent quality deterioration due to foreign matter adhesion.
(2) Since the substrate 4 is a resin material capable of transmitting the laser beam 5 when the substrate 4 is irradiated with the laser beam 5 condensed by the lens 6 as a condensing element, the substrate 4 is the laser beam 5. Therefore, it is possible to easily form the material altered portion 7 at a predetermined position of the substrate 4.
(3) When the substrate 4 is irradiated with the fundamental wave of the YAG laser, the fundamental wave of the YAG laser has a wavelength that is transmissive to the resin material. Easy to form.
(4) The laser beam 5 is split into a plurality of beams by the diffractive optical element 6, so that the beams are split. By irradiating the base 4 with the split beams, a plurality of material altered portions 7 are formed on the base 4. Can be formed. If a plurality of material-affected portions 7 can be formed, the base 4 can be cut and divided in a short time to form the divided pieces Q.
(5) Since the base body 4 can be cut and divided simply by applying the stress F to the base body 4, the divided pieces Q can be easily formed.
(6) Since it can be cut and divided efficiently while maintaining quality, it is possible to provide the wiring board 10 as a more inexpensive flexible circuit board.
(7) Since the wiring board 10 as a cheaper flexible circuit board is provided, the liquid crystal display device 100 as a cheaper electro-optical device can be provided.
(8) Since the liquid crystal display device 100 as a cheaper electro-optical device is provided, the mobile phone 200 as a cheaper electronic device can be provided.

  The present invention has been described above with reference to preferred embodiments. However, the present invention is not limited to the above-described embodiments, and includes modifications as described below, as long as the object of the present invention can be achieved. It can be set to any other specific structure and shape.

  (Modification 1) In the above-described embodiment, as a method of condensing the laser light 5, the light is condensed and irradiated while moving the condensing point in the thickness direction of the substrate 4. However, the present invention is not limited to this. For example, as shown in FIG. 7, a plurality of laser beams 5 having different divergence angles may be condensed and irradiated by a lens 6 as a condensing element. In this way, the same effects as in the embodiment can be obtained, and the time required for forming the material altered portion 7 can be shortened, so that the processing efficiency can be improved.

  (Modification 2) In the above-described embodiment, as a method of condensing the laser beam 5, the light is condensed and irradiated while moving the condensing point in the thickness direction of the substrate 4. However, the present invention is not limited to this. For example, as shown in FIG. 8, the laser beam 5 may be split into a plurality of beams by a lens 6 as a condensing element, which is a diffractive optical element, and irradiated at multiple points simultaneously. In this way, the same effects as in the embodiment can be obtained, and the time required for forming the material altered portion 7 can be shortened, so that the processing efficiency can be improved.

  (Modification 3) In the above-described embodiment, it is desirable that the material altered portion 7 as the modified layer is formed in the entire region in the depth direction of the substrate 4, but is not limited thereto. For example, the substrate 4 may be formed to a depth that can be divided by applying a small stress F. Even in this case, since the divided piece Q can be formed by cutting and dividing the substrate 4, the same effect as in the above-described embodiment can be obtained.

  (Modification 4) In the above-described embodiment, after the material alteration portion 7 as a modified layer is formed, a stress F is applied to the substrate 4 from the outside, and the substrate 4 is cut and divided to form divided pieces Q. However, it is not limited to this. For example, the material altered portion 7 may be formed while applying the stress F to the substrate 4. Even in this case, since the divided piece Q can be formed by cutting and dividing the substrate 4, the same effect as in the above-described embodiment can be obtained.

Explanatory drawing for demonstrating the formation method of the material alteration part as a modified layer by a laser beam. It is a figure which shows the manufacturing method which cut | disconnects and divides | segments the base | substrate in this embodiment, and forms a division | segmentation piece, The figure (a) is a figure which shows the formation process of a material alteration part, The figure (b) It is a figure which shows the state which applies stress, The figure (c) is a figure which shows a division | segmentation piece. The figure which shows the manufacturing method which cuts and divides | segments the tape-shaped board | substrate in this embodiment, and forms a wiring board. Explanatory drawing for demonstrating the conveyance method of a tape-shaped board | substrate. The figure which shows an electro-optical apparatus. FIG. 9 illustrates an electronic device. The figure which shows the example which condenses and irradiates the several laser beam from which the divergence angle differs in the modification 1 with a condensing element. The figure which shows the example which divides | segments the laser beam in the modification 2 into a several beam with a diffractive optical element, and irradiates multiple points simultaneously.

Explanation of symbols

DESCRIPTION OF SYMBOLS 4 ... Board | substrate as a base | substrate, 5 ... Laser beam, 6 ... Lens as a condensing element, 7 ... Material alteration part as a modification layer, 10 ... Wiring board as a flexible circuit board, 100 ... Liquid crystal as an electro-optical device Display device, 200... Mobile phone as electronic device, F... Stress, Q.

Claims (8)

A method for producing a substrate made of a resin material,
Irradiating the base with a laser beam to form a material altered portion; and
Applying stress to the substrate to form divided pieces;
A method for producing a substrate, comprising: In the manufacturing method of the base according to claim 1,
The base is made of a material made of a resin material that is transparent to laser light,
In the step of forming the material altered portion,
Condensing the laser beam to the substrate with a condensing element,
A method of manufacturing a substrate, wherein the material-affected portion is formed. In the manufacturing method of the base | substrate of Claim 1 or Claim 2,
In the step of forming the material altered portion,
The laser beam is a YAG laser and is irradiated with a fundamental wave of the YAG laser.
A method for manufacturing a substrate, comprising forming the material-affected portion. In the manufacturing method of the base according to any one of claims 1 to 3,
In the step of forming the material altered portion,
Branching the laser light into a plurality of beams by a diffractive optical element, irradiating the plurality of beams,
A method for manufacturing a substrate, comprising forming the material-affected portion. In the manufacturing method of the base according to any one of claims 1 to 4,
In the step of forming the divided pieces,
A method of manufacturing a substrate, comprising applying the stress to the substrate in any one of bending stress and tensile stress to form the divided pieces.   A flexible circuit board formed by using the method for manufacturing a substrate according to any one of claims 1 to 5.   An electro-optical device comprising the flexible circuit board according to claim 6. An electronic apparatus comprising the electro-optical device according to claim 7.

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