JP2017102315A - Method of forming hole for wiring and electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of forming a hole for wiring for strengthening fixation of a hole for wiring formed in an electronic device with a conductive material introduced into the hole for wiring.SOLUTION: A liquid crystal panel 1 comprising a first glass substrate 3, a second glass substrate 4 arranged opposite to the first glass substrate 3, and a sealing member 5 interposed between both substrates 3 and 4 is irradiated with a pulse laser from the first glass substrate 3 side, and thereby forming a hole for wiring 8 that penetrates through the first glass substrate 3 and sealing member 5 in the thickness direction and has a hole bottom 8a in the thickness of the second glass substrate 4.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method for forming wiring holes in an electronic device such as a liquid crystal panel, and an electronic device in which the wiring holes are formed.

  As is well known, a liquid crystal panel is composed of two glass substrates facing each other, a color filter substrate on which BM, RGB, photo spacers and transparent electrodes are patterned, and an array substrate on which thin film transistors and transparent electrodes are patterned. Is an electronic device. A seal member made of resin (for example, ultraviolet curable resin) is interposed between the two substrates along the peripheral edge of these substrates, and liquid crystal is sealed in the space surrounded by the seal member. (See Patent Document 1).

  By the way, in recent years, from the viewpoint of space saving and wide bus, as a wiring form of the liquid crystal panel, a wiring hole that penetrates both the substrates and the seal member in the thickness direction is formed, and the hole is plated, A form in which a conductive material is introduced into the hole, such as filling the hole with a conductive paste, is used. This hole is formed by, for example, irradiating a liquid crystal panel with a laser and melting and removing the irradiated portion with the heat of the laser.

Japanese Patent Laying-Open No. 2015-161837

  However, when the wiring hole is formed in the manner as described above, the inner peripheral surface of the hole becomes a flat surface with less unevenness. For example, it is introduced into the hole due to thermal expansion of the electronic device. In addition, there is a problem that it is difficult to fix the conductive material and the inner peripheral surface of the hole, for example, the conductive material is easily removed. Such a problem does not occur only when the wiring hole is formed for the liquid crystal panel. Similarly, in the case of forming a wiring hole penetrating both substrates and the interposed resin for other electronic devices having a structure in which a resin is interposed between two glass substrates arranged opposite to each other This is a possible problem.

  This invention made | formed in view of said situation makes it technical subject to strengthen fixation of the hole for wiring formed in an electronic device, and the electroconductive material introduce | transduced into this hole for wiring.

  The method according to the present invention, which was created to solve the above problems, includes a first glass substrate, a second glass substrate disposed opposite the first glass substrate, and a resin interposed between the two substrates. A wiring hole is formed in an electronic device including an interposition member, and one substrate is formed by irradiating the electronic device with a pulse laser from one of the two substrates. And a wiring hole having a hole bottom that penetrates the interposition member in the thickness direction and is within the thickness of the other substrate.

  According to such a method, the pulse laser irradiated to the electronic device is narrowed as it moves from the laser incident surface side to the emission surface (interface with the intervening member) side in one glass substrate. It will be. On the other hand, in the intervening member made of resin, the pulse laser focused in one substrate moves from the laser incident surface (interface with one substrate) side to the emission surface (interface with the other substrate) side. Will spread to the opposite. As a result, the wiring hole is formed such that its diameter contracts as it moves to the hole bottom side in one of the substrates, and its diameter increases as it moves to the hole bottom side in the interposition member. . In other words, the wiring hole is formed such that the one substrate side and the interposition member side have opposite tapers with the interface between the one substrate and the interposition member as a boundary. Therefore, when a conductive material is introduced into the wiring hole, the inner peripheral surface of the hole and the conductive material are easily caught, and both can be firmly fixed. In this method, the wiring hole is formed so that the hole bottom is located within the thickness of the other substrate. In this way, during the formation of the wiring hole, a part of the laser beam of the pulse laser is reflected by the other substrate, and the reflected light interferes with the laser beam to be incident on the other substrate. It becomes. When the wiring hole is formed under such a state, it is possible to form periodic unevenness according to the interference pattern along the thickness direction on the inner peripheral surface in the interposition member of the wiring hole. Become. For this reason, if a conductive material is introduced into the wiring hole, the inner peripheral surface of the hole and the conductive material are more easily caught due to the presence of periodic irregularities, so that both can be more firmly fixed. Furthermore, in this method, the following actions / effects can be obtained as secondary effects. That is, it is not necessary to form a through hole penetrating all the substrates and the interposition member as the wiring hole, and the time required for forming the wiring hole can be shortened, so that the wiring hole is formed. It becomes possible to improve the manufacturing efficiency of an electronic device. In addition, as compared with the case where the wiring hole is a through hole penetrating all the substrates and the interposition member, it is possible to suppress the occurrence of problems such as distortion in both substrates due to laser irradiation.

  In the above method, the depth of the wiring hole formed in the other substrate is preferably 50% or less with respect to the thickness of the other substrate. Further, it is preferable to use a laser having a wavelength of 8.5 μm to 14 μm as the pulse laser and a substrate having a reflectance of 5% or more for the light having a wavelength of 8.5 μm to 14 μm as the other substrate.

  If it does in this way, it will become easy to reflect a part laser beam of a pulse laser with the other board | substrate. For this reason, it becomes easier to form periodic irregularities on the inner peripheral surface in the interposition member of the wiring hole. As a result, the inner peripheral surface of the wiring hole and the conductive material can be more firmly fixed.

  In the above method, it is preferable that the interface between the first glass substrate and the interposition member is partially peeled along the inner peripheral surface of the wiring hole.

  According to this configuration, when the conductive material is introduced into the wiring hole, the conductive material enters between the first glass substrate and the interposition member. Therefore, the inner peripheral surface of the wiring hole and the conductive material are more easily caught, and both can be fixed more firmly.

  If the above method for forming a wiring hole is executed, a first glass substrate, a second glass substrate disposed to face the first glass substrate, and an intervening member made of a resin interposed between the two substrates, The wiring device includes a wiring hole that penetrates one of the substrates and the interposition member in the thickness direction and has a hole bottom within the thickness of the other substrate. An electronic device whose diameter shrinks as it moves toward the hole bottom in one of the substrates and expands as it moves toward the hole bottom in the interposition member is obtained.

  In addition, if the above wiring hole forming method is executed, an electronic device in which the depth of the wiring hole formed in the other substrate is 50% or less with respect to the thickness of the other substrate can be obtained. .

  In addition, if the above-described method for forming a wiring hole is executed, the inclination angle at which the inner peripheral surface of the wiring hole is inclined with respect to the center line of the hole is 0.1 ° to 30 ° in one substrate. And it is possible to obtain the electronic device which is 1 degree-45 degrees in the interposition member.

  Further, if the above-described wiring hole forming method is executed, an electronic device in which periodic irregularities are formed along the thickness direction on the inner peripheral surface of the interposition member of the wiring hole can be obtained.

  In addition, if the above-described wiring hole forming method is executed, an electronic device in which the interface between the first glass substrate and the interposition member is partially peeled along the inner peripheral surface of the wiring hole can be obtained. is there.

  According to the electronic device configured as described above, it is possible to obtain the same operation and effect as those already described in the above-described method for forming a wiring hole.

  According to the present invention, when the conductive material is introduced into the wiring hole, the inner peripheral surface of the hole and the conductive material are easily caught. Therefore, both the inner peripheral surface of the hole and the conductive material are strengthened. It is possible to fix.

It is a vertical side view which shows the formation method of the hole for wiring which concerns on embodiment of this invention. It is a vertical side view which shows the formation method of the hole for wiring which concerns on embodiment of this invention. It is a vertical side view which shows the formation method of the hole for wiring which concerns on embodiment of this invention. It is a vertical side view which shows the electronic device which concerns on embodiment of this invention. It is an enlarged view which expands and shows the A section in FIG. It is an enlarged view which expands and shows the B section in FIG.

  Hereinafter, a method for forming a wiring hole according to an embodiment of the present invention and an electronic device obtained by executing this method will be described with reference to the accompanying drawings.

  As shown in FIGS. 1 to 3, the method for forming a wiring hole according to the embodiment of the present invention forms a wiring hole by irradiating a liquid crystal panel 1 as an electronic device with a pulse laser 2. Is the method.

  The liquid crystal panel 1 includes, as main constituent elements, a first glass substrate 3, a second glass substrate 4 disposed to face the first glass substrate 3, and an interposed member interposed between the substrates 3 and 4. The sealing member 5 and the metal wiring 6 formed on the second glass substrate 4 are provided.

  Each of the first glass substrate 3 and the second glass substrate 4 has a rectangular shape and a thickness of 1 μm to 400 μm. The width of the gap (cell gap) formed between the substrates 3 and 4 is set to 0.5 μm to 100 μm. The first glass substrate 3 is a color filter substrate on which BM, RGB, photo spacers, and transparent electrodes (all not shown) are formed. On the other hand, the second glass substrate 4 is an array substrate on which a thin film transistor and a transparent electrode (both not shown) are patterned. Of the substrates 3 and 4, the second glass substrate 4 is a substrate having a reflectance of 5% or more with respect to light having a wavelength of 8.5 μm to 14 μm.

  The sealing member 5 bonds the first glass substrate 3 and the second glass substrate 4 and is disposed along the peripheral edge portions of both the substrates 3 and 4. Liquid crystal 7 is sealed in the space surrounded by the seal member 5. The resin constituting the seal member 5 is, for example, an ultraviolet curable resin. The metal wiring 6 is a wiring for sending a driving signal to a driving circuit (not shown). The metal constituting the metal wiring 6 is, for example, aluminum, and molybdenum, for example, is used as the barrier metal.

  In this wiring hole forming method, the liquid crystal panel 1 is irradiated with the pulse laser 2 from the first glass substrate 3 side. In the present embodiment, irradiation is performed so that the optical axis 2 a of the pulse laser 2 extends in the thickness direction of the first glass substrate 3 and the second glass substrate 4.

Here, as the pulse laser 2, a CO ₂ laser, a CO laser, a fiber laser, or the like can be used. The wavelength of the pulse laser 2 is preferably 2.5 μm to 15 μm. In this embodiment, the wavelength is 8.5 μm to 14 μm. The pulse width is more preferably 0.05 μs to 50 μs. Furthermore, the frequency is preferably 100 Hz to 20 kHz. In addition, the pulse energy is preferably 10 μJ to 10 mJ. The polarized light of the pulse laser 2 is circularly polarized, and the focal position of the pulse laser 2 is the surface of the first glass substrate 3 (an incident surface 3a described later). Further, the number of shots of the pulse laser 2 is not particularly limited, but in this embodiment, three shots are used.

  As shown in FIG. 1, the pulse laser 2 irradiated to the liquid crystal panel 1 moves from the laser incident surface 3 a side to the emission surface 3 b (interface with the seal member 5) side in the first glass substrate 3. It will be squeezed. On the other hand, as shown in FIG. 2, in the sealing member 5, the pulse laser 2 focused in the first glass substrate 3 is irradiated from the laser incident surface 5a (interface with the first glass substrate 3) side to the emission surface 5b. As it moves to the (interface with the second glass substrate 4) side, it spreads in the opposite direction. Further, as shown in FIG. 3, in the second glass substrate 4, the pulse laser 2 spread in the seal member 5 moves from the laser incident surface 4 a (interface with the seal member 5) side to the emission surface 4 b side. It will be squeezed again as you go.

  In both the substrates 3 and 4 and the seal member 5, the region irradiated with the pulse laser 2 is melted by the heat of the laser. Accordingly, wiring holes are gradually formed in the liquid crystal panel 1 from the first glass substrate 3 side to the second glass substrate 4 side. During the formation of the hole for wiring, a part of the laser beam of the pulse laser 2 is reflected by the second glass substrate 4, and this reflected light and the laser beam to be incident on the second glass substrate 4 interfere with each other. To do.

  As shown in FIG. 4, the pulse laser 2 is irradiated with the wiring hole 8 penetrating the first glass substrate 3, the seal member 5, and the metal wiring 6, and the hole bottom 8 a of the second glass substrate 4. Continue until formed within the thickness of. At this time, the depth D of the wiring hole 8 formed in the second glass substrate 4 is set to 50% or less with respect to the thickness of the second glass substrate 4.

  Thus, the liquid crystal panel 1 in which the wiring holes 8 are formed is obtained. In this liquid crystal panel 1, the wiring hole 8 is formed in a tapered shape whose diameter contracts as it moves to the hole bottom 8 a side in the first glass substrate 3, and the hole bottom 8 a side in the seal member 5. It is formed in the taper shape which a diameter expands as it transfers to. That is, the wiring hole 8 is formed so that the first glass substrate 3 side and the sealing member 5 side have opposite tapers with the interface between the first glass substrate 3 and the sealing member 5 as a boundary. Yes.

  Here, when the wiring hole 8 is formed by the pulse laser 2 irradiated under the above-described conditions, the inner peripheral surface of the wiring hole 8 in the first glass substrate 3 is inclined with respect to the center line 8b of the hole. The inclined angle θ1 is 0.1 ° to 30 °. On the other hand, the inclination angle θ2 at which the inner peripheral surface of the wiring hole 8 in the seal member 5 is inclined with respect to the center line 8b of the hole is 1 ° to 45 °. Further, as shown in FIG. 5, periodic irregularities according to the interference pattern are formed along the thickness direction on the inner peripheral surface of the wiring hole 8 in the seal member 5. The pitch P of the unevenness is 0.5 μm to 20 μm. Moreover, the height H of the site | part which became convex in the unevenness | corrugation will be 0.5 micrometer-5 micrometers. In addition, this periodic unevenness may be formed in the whole area | region of the internal peripheral surface in the sealing member 5 of the hole 8 for wiring, and may be formed only in a one part area | region. In addition, as shown in FIG. 6, the interface between the first glass substrate 3 and the sealing member 5 is partially peeled along the inner peripheral surface of the wiring hole 8. The width Y of the peeled interface is 0.1 μm to 50 μm. In addition, the dimension Z at which the interface opens along the thickness direction by peeling is 0.1 μm to 20 μm.

  Hereinafter, main actions and effects of the above-described wiring hole forming method will be described.

  In the liquid crystal panel 1 obtained by the above method for forming a wiring hole, the wiring hole 8 is on the first glass substrate 3 side and the sealing member 5 side with the interface between the first glass substrate 3 and the sealing member 5 as a boundary. Are formed so as to be tapered in opposite directions. In addition to this, periodic irregularities are formed along the thickness direction on the inner peripheral surface of the sealing member 5 of the wiring hole 8. Therefore, if the conductive material is introduced into the wiring hole 8 by plating or filling the wiring hole 8 with a conductive paste, the inner peripheral surface of the wiring hole 8 and the conductive material are formed. It becomes easy to catch and it becomes possible to fix both firmly.

  Here, the method for forming a wiring hole according to the present invention is not limited to the mode described in the above embodiment. As a modification of the above embodiment, the pulse laser may be irradiated so that the optical axis of the pulse laser is inclined with respect to the thickness direction of the first glass substrate and the second glass substrate. Further, the polarized light of the pulse laser may be polarized light other than circularly polarized light, such as linearly polarized light, elliptically polarized light, azimuth polarized light, and radial polarized light.

  Further, as a modification of the above-described embodiment, not only the pulse laser that irradiates the liquid crystal panel from the first glass substrate side, but also a new pulse laser that is irradiated from any direction in the seal member. You may make the pulse laser irradiated from the 1st glass substrate side interfere with the newly irradiated pulse laser. Even if it does in this way, it is possible to form the periodic unevenness | corrugation according to an interference pattern in the internal peripheral surface in the sealing member of the hole for wiring.

  Furthermore, in the above embodiment, the wiring hole is formed in the liquid crystal panel. However, an electronic device to which the wiring hole forming method according to the present invention can be applied is included in the liquid crystal panel. It is not limited. This method is also applicable to the case of forming wiring holes for other electronic devices having a structure in which an intervening member made of resin is interposed between two glass substrates arranged opposite to each other. can do. Examples of electronic devices to which the present invention can be applied include organic EL panels and touch panels.

DESCRIPTION OF SYMBOLS 1 Liquid crystal panel 2 Pulse laser 3 1st glass substrate 4 2nd glass substrate 5 Sealing member 8 Hole for wiring 8a Hole bottom 8b Center line D Depth θ1 Inclination angle θ2 Inclination angle

Claims (9)

A wiring hole is formed in an electronic device including a first glass substrate, a second glass substrate disposed opposite to the first glass substrate, and an interposed member made of a resin interposed between the two substrates. A method of forming,
By irradiating the electronic device with a pulse laser from one of the two substrates, the one substrate and the interposition member are penetrated in the thickness direction, and a hole bottom is formed within the thickness of the other substrate. A method for forming a wiring hole, comprising forming the wiring hole.   The method for forming a wiring hole according to claim 1, wherein a depth of the wiring hole formed in the other substrate is 50% or less with respect to a thickness of the other substrate.   A laser having a wavelength of 8.5 μm to 14 μm is used as the pulse laser, and a substrate having a reflectance of 5% or more for light having a wavelength of 8.5 μm to 14 μm is used as the other substrate. Or the formation method of the hole for wiring of 2.   4. The wiring hole according to claim 1, wherein an interface between the first glass substrate and the interposition member is partially peeled along an inner peripheral surface of the wiring hole. 5. Forming method. An electronic device comprising a first glass substrate, a second glass substrate disposed to face the first glass substrate, and an interposed member made of a resin interposed between the two substrates,
A wiring hole penetrating one of the substrates and the interposition member in the thickness direction and having a hole bottom in the thickness of the other substrate is formed,
The diameter of the wiring hole shrinks as it moves toward the hole bottom in the one substrate, and expands as it moves toward the hole bottom in the interposition member. And electronic devices.   6. The electronic device according to claim 5, wherein a depth of the wiring hole formed in the other substrate is 50% or less with respect to a thickness of the other substrate.   The inclination angle at which the inner peripheral surface of the wiring hole is inclined with respect to the center line of the hole is 0.1 ° to 30 ° in the one substrate, and 1 ° to 45 ° in the interposition member. The electronic device according to claim 5, wherein the electronic device is provided.   8. The electronic device according to claim 5, wherein periodic irregularities are formed along the thickness direction on an inner peripheral surface of the wiring hole in the interposition member. 9. The electronic device according to claim 5, wherein an interface between the first glass substrate and the interposition member is partially peeled along an inner peripheral surface of the wiring hole. .

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