JP2008251827A - Method for mounting electronic circuit to substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for mounting an electronic circuit to a substrate capable of hardening an ACF of the periphery of the electronic circuit by keeping electrical connection between the electronic circuit and electrodes on the substrate to alleviate the warpage of the substrate even if an area of the ACF is arranged wider than that of an arrangement position of the electronic circuit. <P>SOLUTION: The ACF 3 and an LSI 4 are arranged on a first substrate 1, and the LSI 4 is depressed to the first substrate 1 by heating the ACF 3 by a first heat tool 5. After that, the first substrate 1 is moved to a glass table 8, and the ACF 3 is heated by infrared light irradiated from a lamp 9. At this time, the LSI 4 is heated and depressed to the first substrate 1 by a second heat tool 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for mounting an electronic circuit on a substrate, and more particularly to a method for mounting an electronic circuit on a substrate using an anisotropic conductive film.

  In a display panel such as a liquid crystal display device, a transparent electrode using ITO (Indium Tin Oxide) is disposed on a glass substrate. An anisotropic conductive film may be used to connect the transparent electrode and an electronic circuit such as LSI (Large Scale Integration). An anisotropic conductive film (ACF) includes a large amount of conductive particles inside a resin, and mechanically connects the glass substrate and the LSI with the resin. Further, the transparent electrode and the LSI are electrically connected by the conductive particles. Hereinafter, the anisotropic conductive film is referred to as ACF. When an LSI is mounted on a glass plate using ACF, the LSI is heat-pressed to a glass substrate via the ACF. A technique for mounting an electronic circuit on a glass substrate is called COG (Chip on Glass).

  In Patent Document 1, a liquid crystal display panel is placed on a work table, a lead portion of a flexible substrate is disposed on a terminal portion of the liquid crystal display panel via an ACF, and a heater bar serving as a thermocompression bonding unit is formed thereon. A connection method for pressing is described.

  A specific example of a conventional mounting method for mounting an LSI on a glass substrate by thermocompression bonding will be described with reference to the drawings. FIG. 5 is an explanatory view showing a conventional mounting method for mounting an LSI on a glass substrate. Here, a case where an LSI is mounted on a glass substrate of a liquid crystal display panel will be described as an example. As shown in FIG. 5A, the liquid crystal display panel includes two glass substrates 1 and 2. A liquid crystal (not shown) is sealed between the glass substrates 1 and 2, and polarizing plates 11 and 12 are provided on the outer surfaces of the glass substrates 1 and 2. One glass substrate (hereinafter referred to as a first substrate) 1 is formed larger than the other glass substrate (hereinafter referred to as a second substrate) 2. A transparent electrode (not shown) is drawn from the two substrates 1 and 2 at a portion of the first substrate 1 that protrudes from the second substrate 2. An LSI is mounted on that portion.

  First, ACF 3 is transferred to a portion of the first substrate 1 where the transparent electrode is drawn (see FIG. 5A). Subsequently, the LSI 4 is arranged on the ACF 3 (see FIG. 5B). The above process is performed at a temperature of 80 ° C. or lower, for example.

  After the placement of the LSI, the glass substrate 1 and the LSI 4 are placed between the support table 6 that supports the glass substrate and the heat tool 5 that performs heating, and the LSI 4 is pressed in the direction of the support table 6 while being heated by the heat tool 5. For example, when AC8033 is used as ACF3, the temperature of the heat tool 5 is set to 230 ° C., and pressure is applied at 80 MPa for 5 seconds. At this time, in order to reduce the difference between the thermal expansion of the surface on the heat tool 5 side of the first substrate 1 and the thermal expansion of the surface on the support table 6 side, for example, from the support table 6 side with respect to the first substrate 1 as well. Heat at 50 ° C. By this processing, the ACF 3 resin is cured, and the LSI 4 is mounted on the first substrate 1. AC8033 is an ACF model number, and is an ACF in which gold-plated plastic particles having a diameter of 4 μm are mixed in a thermosetting binder resin having a glass transition temperature (hereinafter referred to as Tg) of 140 ° C.

  In Patent Document 2, an ACF is sandwiched between a TAB and an array substrate, the array substrate is placed on a quartz plate, pressed with a pressure tool from the TAB side, and irradiated with infrared rays from the quartz plate side. The manufacturing direction of the liquid crystal display device that electrically connects the array substrate and the TAB is described.

JP 2006-19391 A (paragraphs 0004-0008, FIG. 7) JP 2001-21911 (paragraphs 0015 and 0016, FIG. 1)

  The conventional mounting method shown in FIG. 5 has the following problems. As shown in FIG. 5, when the ACF 3 is arranged on the first substrate 1 and the LSI 4 is arranged thereon, the ACF 3 is determined from the area of the arrangement position of the LSI 4 in consideration of the LSI 4 being displaced from a desired position when the LSI 4 is arranged. May also be widely arranged. Heat from the heat tool 5 is transmitted to the ACF 3 via the LSI 4 by heat conduction. As a result, even if the portion of the ACF 3 that contacts the LSI 4 is cured, the portion around the LSI 4 remains uncured. If the uncured ACF remains, there is a problem in that electrolytic corrosion occurs on the transparent electrode on the first substrate due to moisture remaining in the ACF.

  In the description illustrated in FIG. 5, the case where the support table 6 side is also heated to 50 ° C. has been described. However, even if the support table 6 side is heated, the temperature of the surface on the heat tool 5 side of the first substrate 1 A difference in expansion occurs due to a temperature difference on the surface on the support table 6 side. Further, stress on the first substrate 1 is also generated when the ACF 3 is cured and contracted by heating. Such a temperature difference between both surfaces of the first substrate 1 and curing shrinkage of the ACF 3 may cause the first substrate 1 to warp. Then, there is a possibility that color unevenness occurs in the display of the display panel due to warpage of the first substrate. Further, if the stress applied to the first substrate 1 decreases due to some factor, the ACF 3 may float from the first substrate 1 or a disconnection may occur.

  In addition, when the ACF 3 is arranged wider than the area where the LSI 4 is arranged and heated with infrared rays as in the method described in Patent Document 2, the temperature of the ACF around the LSI becomes higher, so To harden. When the ACF at the LSI peripheral portion is hardened before the ACF at the LSI arrangement position, the ACF at the LSI arrangement position does not flow to the LSI peripheral portion. As a result, the LSI cannot be properly pressure-bonded via the conductive particles, which may make it difficult to electrically connect the LSI 4 and the electrode on the first substrate 1.

  In addition, heating with infrared rays is difficult to control the temperature, and the heating temperature may be too high or too low. This phenomenon is called overshoot.

  Therefore, the present invention can cure the ACF around the electronic circuit while maintaining the electrical connection between the electronic circuit and the electrode on the substrate even when the ACF is arranged wider than the area of the electronic circuit. An object of the present invention is to provide a method for mounting an electronic circuit on a substrate that can alleviate the warpage of the substrate.

  The method for mounting an electronic circuit on a substrate according to the present invention is a method for mounting an electronic circuit on a substrate in which the electronic circuit is arranged on a substrate provided with electrodes and the electrodes on the substrate and the electronic circuit are electrically connected. An anisotropic conductive film disposing step (for example, step S1) for disposing an anisotropic conductive film on a portion of the substrate (for example, the first substrate 1) where an electrode is provided, and an electronic circuit on the anisotropic conductive film An electronic circuit placement step (eg, step S2) for placing (eg, LSI 4), a first table (eg, support table 6) that supports the substrate, and an anisotropic conductive film interposed between the electronic circuit and the substrate and the electronic circuit Between the first heating and pressing means (for example, the first heat tool 5) that presses while heating the substrate, the electronic circuit is arranged facing the first heating and pressing means, and the first heating and pressing means is provided. Is an anisotropic conductive film through an electronic circuit A first heating step (for example, step S3) that presses the electronic circuit toward the substrate side while heating, a second table (for example, a glass table 8) that is a table that can transmit infrared rays, and a second step that presses the electronic circuit while heating. A substrate is placed between the two heating and pressing means (for example, the second heat tool 7) with the electronic circuit facing the second heating and pressing means, and the second heating and pressing means heats the electronic circuit. A second heating step (for example, heating the anisotropic conductive film by irradiating infrared rays from an infrared irradiation means (for example, lamp 9) that irradiates infrared rays from the back side of the second table while pressing the electronic circuit toward the substrate side. Step S4).

  When a shutter (for example, shutter 25) that blocks infrared rays is provided between the second table and the infrared irradiation means, and infrared irradiation is continued in the infrared irradiation means, and heating by infrared rays is started in the second heating step. It is preferable to open the shutter and close the shutter when heating by infrared rays is finished.

  Further, in the anisotropic conductive film arranging step, the anisotropic conductive film is arranged wider than the area of the arrangement position of the electronic circuit, and in the second heating step, the periphery of the electronic circuit that is uncured after the first heating step. It is preferable to heat the protruding anisotropic conductive film by irradiating infrared rays.

  According to the present invention, even when the ACF is arranged wider than the area where the electronic circuit is arranged, the ACF around the electronic circuit can be cured while maintaining the electrical connection between the electronic circuit and the electrode on the substrate. And warpage of the substrate can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view showing a method of mounting an electronic circuit on a substrate according to the present invention. FIG. 2 is a flowchart showing a method for mounting an electronic circuit on a substrate according to the present invention. In the following description, a case where an LSI, which is an electronic circuit, is mounted on a glass substrate included in a liquid crystal display panel will be described as an example.

  As already described, the liquid crystal display panel includes two glass substrates 1 and 2, and a liquid crystal (not shown) is sealed between the glass substrates 1 and 2. Polarizers 11 and 12 are provided on the surface. Hereinafter, similarly to the case described above, the larger glass substrate 1 is referred to as a first substrate 1, and the other glass substrate 2 is referred to as a second substrate 2. A transparent electrode (not shown) in a region where the liquid crystal exists in the first substrate 1 is drawn out to a portion 21 (hereinafter referred to as a protruding portion 21) where the first substrate 1 extends from the second substrate 2. Yes. Similarly, a transparent electrode (not shown) provided on the second substrate 2 is also drawn out to the protruding portion 21. That is, a transparent electrode (not shown) drawn from the glass substrates 1 and 2 is disposed on the overhanging portion 21. In the present invention, an electronic circuit (LSI in this example) is connected to a transparent electrode via an ACF (anisotropic conductive film).

  First, the ACF 3 is disposed in a portion where the transparent electrode of the protruding portion 21 of the first substrate 1 is provided (step S1). FIG. 1A shows the state of the liquid crystal display panel after step S1. In step S1, for example, the ACF 3 is arranged by transfer. The ACF 3 is provided wider than the area where the LSI is arranged (in other words, the area of the surface of the LSI on the first substrate side).

  After step S1, the LSI 4 is placed on the ACF 3 placed on the first substrate 1 (step S2). FIG. 1B shows the state of the liquid crystal display panel after step S2. Since the ACF 3 is provided wider than the area where the LSI 4 is arranged, the LSI 4 can be connected to the electrode on the first substrate 1 via the ACF 3 even if the arrangement position of the LSI 4 is deviated from a desired position. An ACF 3 is also present around the LSI 4.

  For example, when AC8033 (ACF model number) is used as ACF3, steps S1 and S2 are performed at a temperature of 80 ° C. or less, for example. However, “80 ° C. or lower” shown here is an example, and any temperature corresponding to the type of ACF 3 may be used.

  Subsequently, the first substrate 1 is disposed between the support table 6 and the heat tool 5, and the LSI 4 is pressed toward the first substrate 1 while the ACF 3 is heated by the heat tool 5 (step S3). FIG. 1C shows the state of the liquid crystal display panel in step S3.

  The support table 6 supports the 1st board | substrate 1 arrange | positioned between the heat tools 5 from the bottom. The heat tool 5 is a device that presses the electronic circuit and the ACF interposed between the first substrate and the electronic circuit while heating. Hereinafter, the heat tool used in step S3 is referred to as a first heat tool, as distinguished from the heat tool used in step S4 described later. When the first substrate 1 is disposed between the support table 6 and the first heat tool 5, the LSI 4 is disposed toward the first heat tool 5 and the first substrate 1 is disposed toward the support table 6. In step S3, the first substrate 1 is thus arranged between the support table 6 and the first heat tool 5, and the first heat tool 5 presses the LSI 4 toward the first substrate 1 while heating the ACF 3. To do.

  Further, the support table 6 includes heating means (not shown) such as a heater, and the support table 6 itself generates heat by the heating means. The support table 6 heats the surface of the first substrate 1 opposite to the LSI 4 by generating heat.

  The first heat tool 5 generates heat by a heating means (not shown) such as a heater, and the heat is transmitted to the ACF 3 through the LSI 4 by conduction. That is, the first heat tool 5 heats the ACF 3 by conduction through the LSI 4. As a result, in step S3, the ACF 3 that is in contact with the LSI 4 is heated by the first heat tool 5 and cured.

  For example, when AC8033 is used as ACF3, the temperature of the first heat tool 5 may be set to 230 ° C. in step S3 and pressurized at 80 MPa for 5 seconds. Moreover, the temperature of the support table 6 should just be 50 degreeC.

  The ACF used in the present invention is not limited to the above ACF (AC8033). Further, the temperature, pressure and pressing time of the first heat tool 5 and the heat generation temperature of the support table 6 in step S3 are not limited to the above example. However, the heat generation temperature of the support table 6 is lower than the temperature of the first heat tool 5.

  In step S3, the ACF 3 in contact with the LSI 4 is heated and cured by the first heat tool 5, but the ACF 3 around the LSI 4 remains uncured. Further, the heat generation temperature of the support table 6 is lower than the temperature of the first heat tool 5, and the temperature of the arrangement position of the LSI 4 on the first substrate 1 is higher than the temperature of the opposite surface of the first substrate 1. In addition, stress on the first substrate 1 is generated due to cure shrinkage of the ACF 3. As a result, at the end of step S3, the stress that causes the warp of the first substrate 1 remains.

  Immediately after step S3, the liquid crystal display panel is moved from the support table 6 to the glass table and heated again on the glass table (step S4). FIG. 1D shows the state of the liquid crystal display panel in step S4.

  FIG. 3 is an explanatory diagram showing movement of the liquid crystal display panel from step S3 to step S4. FIG. 3 is a top view of the liquid crystal display panel arranged on each table, and illustration of each heat tool used in steps S3 and S4 is omitted. As shown in FIG. 3A, the first substrate 1 of the liquid crystal display device that has been placed on the support table 6 in step S3 is moved onto the glass table 8 in step S4 (see FIG. 3B). .

  In step S4, the first substrate 1 of the liquid crystal display panel is disposed between the glass table 8 and the second heat tool 7, and the LSI 4 is pressed against the first substrate 1 while the LSI 4 is heated by the second heat tool 7. . Moreover, infrared rays (infra-red: IR) are irradiated from the back side of the glass table 8 by the lamp 9, and the ACF 3 is heated by infrared rays from the glass table 8 side.

  The glass table 8 is a table capable of transmitting infrared rays, and supports the first substrate 1 disposed between the second heat tool 7 from below. The glass table 8 is made of, for example, quartz glass or heat-resistant glass, but may be other materials as long as it is made of a material that can transmit infrared rays.

  The second heat tool 7 is the same heat tool as the first heat tool 5 and presses an electronic circuit such as an LSI mounted on the first substrate 1 while heating.

  When the first substrate 1 is disposed between the glass table 8 and the second heat tool 7, the LSI 4 is disposed on the second heat tool 7 side, and the first substrate 1 is disposed on the glass table 8 side (FIG. 1 (d).)

  Further, as shown in FIG. 1 (d), a lamp 9 for irradiating infrared rays is installed on the back side of the glass table 8 (in other words, on the opposite side of the glass table 8 from the liquid crystal display panel). ing. In step S <b> 4, with the first substrate 1 disposed between the glass table 8 and the second heat tool 7, the infrared rays irradiated by the lamp 9 are irradiated to the ACF 3 through the glass table 8 and the first substrate 1. To heat ACF3.

  Here, the heating start and end of the ACF 3 by infrared rays will be described. FIG. 4 is an explanatory diagram showing the start and end of heating by infrared rays irradiated by the lamp. As shown in FIG. 4, an openable / closable shutter (shielding plate) 25 is provided between the glass table 8 and the lamp 9. 4A shows a state where the shutter 25 is closed, and FIG. 4B shows a state where the shutter 25 is opened. When the shutter 25 is closed, the infrared rays emitted from the lamp 9 are blocked, and the infrared rays do not reach the glass table 8. On the other hand, in the state where the shutter 25 is opened, the infrared rays emitted from the lamp 9 reach the glass table 8.

  The lamp 9 emits infrared light from before the first substrate 1 (not shown in FIG. 4) is arranged on the glass table 8 in step S4 to after the first substrate 1 on the glass table 8 is moved. continue.

  Before the first substrate 1 is placed on the glass table 8, the shutter 25 is in a closed state (see FIG. 4A). That is, the infrared rays irradiated by the lamp 9 are blocked between the lamp 9 and the glass table 8. As a result, infrared rays do not reach the glass table 8. After the first substrate 1 is placed on the glass table 8, the shutter 25 is opened to heat the ACF 3 (not shown in FIG. 4; see FIG. 1 (d)) on the first substrate 1 by infrared irradiation. To start. Further, when the heating of the ACF 3 by the infrared irradiation is stopped, the heating is stopped by closing the shutter 25. Thereafter, the lamp 9 continues to be irradiated with infrared rays.

  In step S4, heating with infrared rays is performed so that the temperature of ACF3 is equal to or higher than the glass transition temperature Tg of the resin contained in ACF3.

  When the ACF 3 is heated by infrared irradiation, the LSI 4 is pressed toward the first substrate 1 while the LSI 4 is heated by the second heat tool 7.

  As described above, in step S4, heating of the ACF 3 by infrared irradiation and heating and pressing of the LSI 4 by the second heat tool 7 are performed simultaneously. The temperature of the 2nd heat tool 7 in step S4 is set lower than the temperature of the surface at the side of the glass table of the 1st board | substrate 1 with which infrared rays are irradiated. Alternatively, the temperature of the second heat tool 7 that minimizes the warp of the first substrate 1 may be obtained experimentally and set to that temperature.

  The heating by the infrared irradiation in step S4 is performed not by conduction but by radiation. Accordingly, since the entire ACF 3 is heated, the uncured ACF around the LSI 4 is also heated. Therefore, the entire ACF 3 can be cured.

  In particular, by irradiating infrared rays from the side opposite to the surface on which the LSI 4 is disposed, the temperature of the ACF 3 around the LSI 4 can be made higher than the temperature of the ACF 3 at the position where the LSI 4 is disposed. The reason why the temperature of the ACF 3 around the LSI 4 is higher than the temperature of the ACF 3 at the position where the LSI 4 is arranged is estimated as follows. The thickness of the ACF 3 at the position where the LSI 4 is arranged is as thin as about 15 μm. As a result, the infrared light transmitted through the glass table 8 and the first substrate 1 also passes through the ACF 3 and reaches the LSI 4 and is scattered. The infrared light scattered at the outer peripheral edge of the LSI 4 reaches the ACF 3 in the peripheral part of the LSI 4. Therefore, the infrared rays that are directly incident through the glass table 8 and the first substrate 1 and the infrared rays scattered by the LSI 4 reach the peripheral portion of the LSI 4, and as a result, the ACF 3 in the peripheral portion of the LSI 4 becomes higher in temperature. Guessed.

  Further, after step S3, the stress generated by the hardening shrinkage of ACF3 in step S3 remains. However, the stress generated in step S3 can be released by irradiating infrared rays in step S4 to reheat ACF3 and setting ACF3 to a temperature equal to or higher than the glass transition temperature Tg. At this time, the LSI 4 is pressed toward the first substrate 1 by the second heat tool 7. Therefore, even if the ACF 3 contributing to the connection between the LSI 4 and the first substrate 1 is reheated to the glass transition temperature Tg or higher, the connection state between the LSI 4 and the first substrate 1 can be prevented from becoming unstable. Further, as described above, since the temperature of the ACF 3 around the LSI 4 is higher than the temperature of the ACF 3 at the position where the LSI 4 is arranged, the distortion of the substrate around the LSI can be alleviated and the distortion of the entire substrate can be alleviated.

  In step S4, infrared irradiation is performed and heating by the second heat tool 7 is also performed. Therefore, the difference in thermal expansion between both surfaces of the first substrate 1 can be reduced, and the occurrence of warpage of the first substrate can be suppressed. Furthermore, it is possible to prevent the heat of ACF 3 heated by infrared irradiation from escaping to the outside through LSI 4 and the temperature of ACF 3 from being lowered.

  Moreover, the heating by infrared irradiation is performed immediately after step S3. Therefore, the ACF 3 at the position where the LSI 4 is disposed can be cured while the ACF 3 at the position where the LSI 4 is disposed is flowed to the peripheral portion, and then the ACF 3 at the peripheral portion can be cured at step S4. Pressure bonding to the substrate can be performed appropriately. If step S4 is performed without performing the process of step 3, the peripheral portion of the LSI 4 that is at a higher temperature is hardened first, the flow of the ACF 3 at the position where the LSI 4 is disposed is hindered, and the LSI 4 cannot be properly crimped. There is a possibility that electrical connection with the electrode on the first substrate 1 becomes difficult. However, in the present invention, since step S4 is performed after step S3, electrical connection between the LSI 4 and the electrode on the first substrate 1 can be reliably performed.

  As described above, in step S4, the ACF 3 in the peripheral portion of the LSI 4 is cured, and the warp of the first substrate 1 is alleviated.

  As a result of step S4, a liquid crystal display panel in which the entire ACF 3 is cured is obtained.

  When step S4 is completed, infrared irradiation to the ACF 3 is stopped by closing the shutter 25 as shown in FIG. Further, the pressing by the second heat tool 7 is also stopped, and the liquid crystal display panel is removed from the glass table 8. Although the infrared irradiation is stopped by closing the shutter 25, the lamp 9 continues the infrared irradiation.

  As described above, according to the present invention, since infrared irradiation is performed in step S4 after step S3, the entire ACF 3 can be heated by radiation to cure the entire ACF 3. Therefore, the electrolytic corrosion of the transparent electrode on the first substrate 1 due to the uncured ACF can be prevented.

  In step S4, since ACF3 is set to a temperature equal to or higher than the glass transition temperature Tg, the stress generated in step S3 can be released and the warpage can be reduced. Therefore, it is possible to prevent the occurrence of color unevenness of the liquid crystal display panel due to warping and the disconnection caused by the release of stress after the LSI 4 is mounted.

  Further, since the ACF 3 at the position where the LSI 4 is arranged is cured in step S3, and the ACF 3 in the peripheral portion of the LSI 4 is cured in step S3, the electrical connection between the LSI 4 and the electrode on the first substrate 1 is ensured. Can do.

  In the present invention, the lamp 9 continues to irradiate infrared rays, opens the shutter 25, starts infrared irradiation to the ACF3, and closes the shutter 25 to stop infrared irradiation to the ACF3. Accordingly, since the state of the lamp 9 does not change, the temperature management of the ACF 3 is facilitated and overshoot can be prevented. When the infrared irradiation is started by changing the lamp 9 itself from the unlit state to the lit state without using the shutter 25 and the infrared irradiation is stopped by changing the lamp 9 itself from the lit state to the unlit state, the temperature control of the ACF 3 is performed. Is difficult and overshoot is likely to occur. Therefore, as described above, it is preferable that the lamp 9 continues the infrared irradiation, starts the infrared irradiation on the ACF 3 by opening the shutter 25, and stops the infrared irradiation on the ACF 3 by closing the shutter 25.

  Further, since the process of step S3 and the process of step S4 are performed on separate tables, it is possible to continuously mount LSIs on a plurality of liquid crystal display panels, and tact (mounting LSIs on one liquid crystal display panel) Time) can be prevented.

  In the present invention, the ACF 3 is reheated in step S4 after step S3. This reheating is performed by irradiation with infrared rays. Therefore, generation | occurrence | production of the distortion of the table (glass table 8) used by step S4 can be suppressed.

  Suppose that the glass transition temperature of ACF is high (for example, 140 ° C.). If the ACF is 140 ° C. or higher regardless of infrared irradiation, the transparent electrode side of the first substrate 1 needs to be heated to 160 ° C. When the ACF is heated not by infrared irradiation but by heat conduction, the heat source temperature on the table side used in step S4 must be 200 ° C. or higher in consideration of heat radiation in the conduction process. Then, the table is distorted due to the temperature difference between the vicinity of the heat source included in the table used in step S4 and the location away from the heat source, and it is difficult to maintain the balance between the table and the second heat tool 7 used in step S4. . In the present invention, in step S4, infrared rays are irradiated through the glass table 8 and the first substrate 1, and the ACF 3 is heated by radiation. Therefore, the above-described table deformation can be prevented.

  The present invention can be suitably applied to mounting an electronic circuit on a substrate included in a display panel.

Explanatory drawing which shows the mounting method of the electronic circuit to the board | substrate of this invention. 4 is a flowchart showing a method for mounting an electronic circuit on a substrate according to the present invention. Explanatory drawing which shows the movement of the liquid crystal display panel in step S3 to step S4. Explanatory drawing which shows the heating start and completion | finish by the infrared rays which a lamp irradiates. Explanatory drawing which shows the conventional mounting method which mounts LSI on a glass substrate.

Explanation of symbols

1 First substrate (glass substrate)
3 ACF (anisotropic conductive film)
4 LSI
5 First Heat Tool 6 Support Table 7 Second Heat Tool 8 Glass Table

Claims (3)

A method of mounting an electronic circuit on a substrate, wherein the electronic circuit is disposed on a substrate provided with an electrode, and the electrode on the substrate and the electronic circuit are electrically connected to each other.
An anisotropic conductive film disposing step of disposing an anisotropic conductive film in a portion of the substrate where the electrode is provided;
An electronic circuit placement step of placing an electronic circuit on the anisotropic conductive film;
Between the first table that supports the substrate and the first heating and pressing means that presses the electronic circuit and the anisotropic conductive film interposed between the substrate and the electronic circuit while heating the first heating of the electronic circuit. A first heating step in which the substrate is arranged toward the pressing means side, and the first heating pressing means presses the electronic circuit to the substrate side while heating the anisotropic conductive film via the electronic circuit;
Between the second table, which is a table through which infrared rays can be transmitted, and the second heating and pressing means that presses the electronic circuit while heating, the substrate is disposed with the electronic circuit facing the second heating and pressing means, The second heating and pressing means presses the electronic circuit to the substrate side while heating the electronic circuit, and the infrared conductive film is irradiated with infrared rays from the infrared irradiation means that irradiates infrared rays from the back side of the second table. And a second heating step of heating. A method of mounting an electronic circuit on a substrate. A shutter for blocking infrared rays is provided between the second table and the infrared irradiation means, the infrared irradiation means is continuously irradiated with infrared rays, and the shutter is opened when heating by infrared rays is started in the second heating step, The method for mounting an electronic circuit on a substrate according to claim 1, wherein the shutter is closed when heating by infrared rays is finished. In the anisotropic conductive film placement step, the anisotropic conductive film is placed wider than the area of the placement position of the electronic circuit,
The substrate according to claim 1 or 2, wherein in the second heating step, the anisotropic conductive film protruding from the periphery of the uncured electronic circuit after the first heating step is heated by irradiation with infrared rays. Mounting method of electronic circuit.

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