Electrical circuit forming method and electrical circuit forming device

Abstract

The electric circuit forming method includes: a wiring forming step for forming metal wiring on a resin layer; a first application step for applying a conductive fluid onto an expected mounting position of an electrode of an electronic component on the metal wiring; a first curing step for curing the conductive fluid applied during the first application step; a second application step for applying a conductive fluid onto an expected mounting position of a component body of the electronic component; a mounting step for mounting the electronic component so that the electrode is in contact with the conductive fluid cured during the first curing step and the component body is in contact with the conductive fluid applied during the second application step; and a second curing step for curing the conductive fluid applied during the second application step after the electronic component has been mounted during the mounting step.

Description

[Technical field]

[0001] The present invention relates to a method for forming an electric circuit that electrically connects metal wiring and electronic components. [Background technology]

[0002] The following patent documents disclose a method for forming an electric circuit that electrically connects metal wiring and electronic components. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-152161 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present specification is to provide a method for appropriately electrically connecting metal wiring and electronic components. [Means for solving the problem]

[0005] In order to solve the above problems, the present specification provides a wiring forming step of forming metal wiring on a resin layer, and a step of attaching an electrode of an electronic component to the metal wiring at a position where the electrode of the electronic component is to be attached. By dispenser A first application step of applying a conductive fluid, a first curing step of curing the conductive fluid applied in the first application step, and applying the conductive fluid to a position on the resin layer where a component body of the electronic component is to be mounted. By dispenser The present invention discloses a method for forming an electric circuit, the method including: a second application step of applying a conductive fluid; an attachment step of attaching the electronic component so that the electrode comes into contact with the conductive fluid that has been hardened in the first hardening step and the component body comes into contact with the conductive fluid that has been applied and not hardened in the second application step; and a second curing step of curing the conductive fluid applied in the second application step after the electronic component has been attached in the attachment step. Effect of the Invention

[0006] In the present disclosure, a conductive fluid is applied to a position on a metal wiring where an electrode of an electronic component is to be mounted, and the conductive fluid is cured. A conductive fluid is also applied to a position where a component body of the electronic component is to be mounted. The electronic component is then mounted so that the electrode contacts the cured conductive fluid and the component body contacts the uncured conductive fluid, and the uncured conductive fluid is then cured. This allows the metal wiring and the electronic component to be appropriately electrically connected. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a circuit forming device. [Diagram 2] FIG. 2 is a block diagram showing a control device. [Diagram 3] 1 is a cross-sectional view showing a heat-sensitive release film attached onto a base. [Figure 4] FIG. 2 is a cross-sectional view showing a circuit board with a resin laminate formed thereon. [Diagram 5] FIG. 2 is a cross-sectional view showing a circuit board having wiring formed on a resin laminate. [Figure 6] 1 is a cross-sectional view showing a circuit board in a state in which a conductive resin paste is applied onto wiring. [Figure 7] 1 is a cross-sectional view showing a circuit board in a state in which a conductive resin paste is applied onto a resin laminate. [Figure 8] FIG. 2 is a cross-sectional view showing a circuit board with electronic components mounted thereon. [Figure 9] 1 is a cross-sectional view showing a circuit board in a state in which a thermosetting resin has been injected between an upper surface of a resin laminate and a lower surface of a component body of an electronic component. FIG. [Figure 10] 4 is a cross-sectional view showing a circuit board with an electronic component pressed against a resin laminate. FIG. [Figure 11] 1 is a cross-sectional view showing a circuit board in a state in which a thermosetting resin is discharged around an electronic component. [Figure 12]1 is a cross-sectional view of a circuit board in a state in which it is heated while being compressed; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] 1 shows a circuit-forming apparatus 10. The circuit-forming apparatus 10 includes a conveying device 20, a first modeling unit 22, a second modeling unit 23, a third modeling unit 24, a fourth modeling unit 25, a compression unit 26, a mounting unit 27, and a control device (see FIG. 2) 28. The conveying device 20, the first modeling unit 22, the second modeling unit 23, the third modeling unit 24, the fourth modeling unit 25, the compression unit 26, and the mounting unit 27 are disposed on a base 29 of the circuit-forming apparatus 10. The base 29 is generally rectangular in shape, and in the following description, the longitudinal direction of the base 29 is referred to as the X-axis direction, the lateral direction of the base 29 is referred to as the Y-axis direction, and the direction perpendicular to both the X-axis direction and the Y-axis direction is referred to as the Z-axis direction.

[0009] The transport device 20 includes an X-axis slide mechanism 30 and a Y-axis slide mechanism 32. The X-axis slide mechanism 30 includes an X-axis slide rail 34 and an X-axis slider 36. The X-axis slide rail 34 is disposed on a base 29 so as to extend in the X-axis direction. The X-axis slider 36 is held by the X-axis slide rail 34 so as to be slidable in the X-axis direction. The X-axis slide mechanism 30 includes an electromagnetic motor (see FIG. 2) 38, and the X-axis slider 36 is moved to an arbitrary position in the X-axis direction by the drive of the electromagnetic motor 38. The Y-axis slide mechanism 32 includes a Y-axis slide rail 50 and a stage 52. The Y-axis slide rail 50 is disposed on the base 29 so as to extend in the Y-axis direction and is movable in the X-axis direction. One end of the Y-axis slide rail 50 is connected to the X-axis slider 36. The stage 52 is held by the Y-axis slide rail 50 so as to be slidable in the Y-axis direction. Furthermore, the Y-axis slide mechanism 32 has an electromagnetic motor (see FIG. 2) 56, and the stage 52 moves to an arbitrary position in the Y-axis direction by driving the electromagnetic motor 56. As a result, the stage 52 moves to an arbitrary position on the base 29 by driving the X-axis slide mechanism 30 and the Y-axis slide mechanism 32.

[0010] The stage 52 has a base 60, a holding device 62, a lifting device (see FIG. 2) 64, and a heater (see FIG. 2) 66. The base 60 is formed in a flat plate shape, and a substrate is placed on the upper surface. The holding devices 62 are provided on both sides of the base 60 in the X-axis direction. The substrate is fixedly held by clamping both edges in the X-axis direction of the substrate placed on the base 60 between the holding devices 62. The lifting device 64 is disposed below the base 60, and raises and lowers the base 60. The heater 66 is built into the base 60, and heats the substrate placed on the base 60 to a desired temperature.

[0011] The first modeling unit 22 is a unit that models the wiring of a circuit board, and has a first printing section 72 and a baking section 74. The first printing section 72 has an inkjet head (see FIG. 2) 76 that ejects metal ink in a linear shape. The metal ink is a dispersion of nanometer-sized metal particles, such as silver particles, in a solvent. The surfaces of the metal particles are coated with a dispersant to prevent aggregation in the solvent. The inkjet head 76 ejects the metal ink from multiple nozzles, for example, by a piezo method using a piezoelectric element.

[0012] The baking unit 74 has an infrared irradiation device 78 (see FIG. 2). The infrared irradiation device 78 is a device that irradiates the ejected metal ink with infrared rays, and the metal ink irradiated with infrared rays is baked to form wiring. Note that baking of metal ink is a phenomenon in which, by applying energy, the solvent is evaporated and the protective film for the metal particles, i.e., the dispersant is decomposed, and the metal particles come into contact or fuse together, thereby increasing the conductivity. Then, by baking the metal ink, metal wiring is formed.

[0013] The second modeling unit 23 is a unit that models a resin layer of a circuit board, and has a second printing unit 84 and a curing unit 86. The second printing unit 84 has an inkjet head (see FIG. 2) 88 that ejects ultraviolet curable resin. The ultraviolet curable resin is a resin that is cured by irradiation with ultraviolet rays. The inkjet head 88 may be, for example, a piezo type that uses a piezoelectric element, or a thermal type that heats resin to generate bubbles and ejects the resin from multiple nozzles.

[0014] The curing section 86 has a flattening device (see FIG. 2) 90 and an irradiation device (see FIG. 2) 92. The flattening device 90 flattens the upper surface of the ultraviolet curing resin discharged by the inkjet head 88, for example, by leveling the surface of the ultraviolet curing resin while scraping off excess resin with a roller or a blade, thereby making the thickness of the ultraviolet curing resin uniform. The irradiation device 92 is equipped with a mercury lamp or LED as a light source, and irradiates the discharged ultraviolet curing resin with ultraviolet rays. This causes the discharged ultraviolet curing resin to harden, forming a resin layer.

[0015] The third modeling unit 24 is a unit that models a connection portion between an electrode of an electronic component and a wiring on a circuit board, and has a third printing unit 100. The third printing unit 100 has a dispenser (see FIG. 2) 106 that dispenses a conductive resin paste. The conductive resin paste is a resin that hardens when heated at a relatively low temperature and has micrometer-sized metal particles dispersed in it. The metal particles are in the form of flakes, and the viscosity of the conductive resin paste is relatively high compared to that of metal ink. The amount of conductive resin paste dispensed by the dispenser 106 is controlled by the inner diameter of a needle, the pressure during dispensing, and the dispensing time.

[0016] The conductive resin paste dispensed by the dispenser 106 is heated by the heater 66 built into the base 60, and the resin in the heated conductive resin paste hardens. At this time, the resin in the conductive resin paste hardens and shrinks, and the flake-shaped metal particles dispersed in the resin come into contact with each other. This allows the conductive resin paste to exhibit conductivity. The resin in the conductive resin paste is an organic adhesive, and exerts adhesive power by hardening when heated.

[0017] The fourth modeling unit 25 is a unit that models resin for fixing electronic components to a circuit board, and has a fourth printing unit 110. The fourth printing unit 110 has a dispenser (see FIG. 2) 116 that dispenses thermosetting resin. Thermosetting resin is resin that hardens when heated. The dispenser 116 is, for example, a piezo type that uses a piezoelectric element. The thermosetting resin dispensed by the dispenser 116 is heated by a heater 66 built into the base 60 and hardens.

[0018] The compression unit 26 is a unit for compressing the circuit board, and has a compression section 120. The compression section 120 has a compression plate (see FIG. 10) 122, a rubber sheet (see FIG. 10) 124, and a cylinder (see FIG. 2) 126. The rubber sheet 124 is made of silicon rubber and has a sheet shape with a plate thickness. The compression plate 122 is made of steel and has a plate shape. The rubber sheet 124 is attached to the lower surface of the compression plate 122, and the compression plate 122 is pressed against the circuit board by the operation of the cylinder 126. As a result, the circuit board is compressed by the compression plate 122 via the rubber sheet 124. The force compressing the board can be controllably changed by controlling the operation of the cylinder 126.

[0019] Furthermore, mounting unit 27 is a unit that mounts electronic components on a circuit board, and has supply section 130 and mounting section 132. Supply section 130 has a plurality of tape feeders (see FIG. 2) 134 that feed taped electronic components one by one, and supplies the electronic components at a supply position. Note that supply section 130 is not limited to tape feeder 134, and may be a tray-type supply device that picks up and supplies electronic components from a tray. Supply section 130 may be configured to include both tape-type and tray-type supply devices, or other types of supply devices.

[0020] The mounting unit 132 has a mounting head (see FIG. 2) 136 and a moving device (see FIG. 2) 138. The mounting head 136 has a suction nozzle (not shown) for suctioning and holding an electronic component. The suction nozzle sucks and holds the electronic component by sucking air when negative pressure is supplied from a positive / negative pressure supplying device (not shown). Then, the positive / negative pressure supplying device supplies a slight positive pressure to the suction nozzle, which releases the electronic component. The moving device 138 moves the mounting head 136 between the supply position of the electronic component by the tape feeder 134 and the board placed on the base 60. As a result, in the mounting unit 132, the electronic component supplied from the tape feeder 134 is held by the suction nozzle, and the electronic component held by the suction nozzle is mounted on the board.

[0021] 2, the control device 28 includes a controller 140 and a plurality of drive circuits 142. The plurality of drive circuits 142 are connected to the electromagnetic motors 38, 56, the holding device 62, the lifting device 64, the heater 66, the inkjet head 76, the infrared irradiation device 78, the inkjet head 88, the flattening device 90, the irradiation device 92, the dispenser 106, the dispenser 116, the cylinder 126, the tape feeder 134, the mounting head 136, and the moving device 138. The controller 140 includes a CPU, a ROM, a RAM, and the like, and is mainly a computer, and is connected to the plurality of drive circuits 142. As a result, the operations of the conveying device 20, the first modeling unit 22, the second modeling unit 23, the third modeling unit 24, the fourth modeling unit 25, the compression unit 26, and the mounting unit 27 are controlled by the controller 140.

[0022] In the circuit-forming device 10, a resin laminate is formed on the base 60 by the above-mentioned configuration, and wiring is formed on the upper surface of the resin laminate. Then, the electrodes of the electronic components are electrically connected to the wiring via the conductive resin paste, and the electronic components are fixed by the resin to form a circuit board.

[0023] Specifically, as shown in FIG. 3, a heat-sensitive release film 150 is first laid on the upper surface of the base 60 of the stage 52. The heat-sensitive release film 150 has adhesiveness and therefore adheres appropriately to the upper surface of the base 60. Then, a circuit board is formed on the heat-sensitive release film 150, and the heat-sensitive release film 150 adheres closely to the base 60, thereby preventing the circuit board from being displaced during circuit formation. The adhesiveness of the heat-sensitive release film 150 decreases when heated. Therefore, after the circuit board is formed on the heat-sensitive release film 150, the heat-sensitive release film 150 can be easily peeled off from the base 60 together with the circuit board formed on the heat-sensitive release film 150 by heating the heat-sensitive release film 150.

[0024] When the heat-sensitive peeling film 150 is laid on the base 60, the stage 52 is moved to below the second modeling unit 23. Then, in the second modeling unit 23, a resin laminate 152 is formed on the heat-sensitive peeling film 150, as shown in Fig. 4. The resin laminate 152 has a cavity 154, and is formed by repeatedly discharging an ultraviolet curing resin from the inkjet head 88 and irradiating the discharged ultraviolet curing resin with ultraviolet rays by the irradiation device 92.

[0025] More specifically, in the second printing section 84 of the second modeling unit 23, the inkjet head 88 ejects the ultraviolet curing resin in a thin film on the upper surface of the heat-sensitive peeling film 150. Then, after the ultraviolet curing resin is ejected in a thin film, the ultraviolet curing resin is flattened by the flattening device 90 in the curing section 86 so that the film thickness of the ultraviolet curing resin becomes uniform. Then, the irradiation device 92 irradiates the thin film of the ultraviolet curing resin with ultraviolet rays. As a result, a thin film resin layer 155 is formed on the heat-sensitive peeling film 150.

[0026] Next, the inkjet head 88 ejects a thin film of ultraviolet curable resin onto the thin film resin layer 155. The thin film of ultraviolet curable resin is then flattened by the flattening device 90, and the irradiation device 92 irradiates the ultraviolet curable resin ejected into the thin film with ultraviolet light, thereby laminating the thin film resin layer 155 on the thin film resin layer 155. In this manner, ejection of the ultraviolet curable resin onto the thin film resin layer 155 and irradiation with ultraviolet light are repeated, and a plurality of resin layers 155 are laminated, thereby forming a first laminate 156.

[0027] Next, the inkjet head 88 ejects the ultraviolet curing resin so that a predetermined portion of the upper surface of the first laminate 156 is exposed. Then, when the ultraviolet curing resin is ejected in a thin film, the ultraviolet curing resin is flattened in the curing section 86 so that the film thickness of the ultraviolet curing resin becomes uniform. Then, the irradiation device 92 irradiates the thin film of the ultraviolet curing resin with ultraviolet rays. As a result, a thin film layer 157 of resin is formed on the first laminate 156.

[0028] Next, the inkjet head 88 discharges the ultraviolet curing resin in a thin film only on the portion above the thin film layer 157. That is, the inkjet head 88 discharges the ultraviolet curing resin in a thin film on the thin film layer 157 so that a predetermined portion of the upper surface of the first laminate 156 is exposed. Then, the thin film of the ultraviolet curing resin is flattened by the flattening device 90, and the irradiation device 92 irradiates the ultraviolet curing resin discharged in a thin film with ultraviolet light, so that the thin film layer 157 is laminated on the thin film layer 157. In this way, the discharge of the ultraviolet curing resin on the thin film layer 157 and the irradiation of ultraviolet light are repeated, and a plurality of thin film layers 157 are laminated, so that the second laminate 158 is formed. As a result, the second laminate 158 is formed on the first laminate 156, so that the resin laminate 152 in which the step portion between the first laminate 156 and the second laminate 158 functions as the cavity 154 is formed.

[0029] When the resin laminate 152 is formed by the above-mentioned procedure, the stage 52 is moved below the first modeling unit 22. Then, in the first printing section 72 of the first modeling unit 22, the inkjet head 76 ejects the metal ink 160 in a line shape according to the circuit pattern onto the cavity 154 of the resin laminate 152, that is, onto the upper surface of the first laminate 156, as shown in FIG. 5. Next, in the baking section 74 of the first modeling unit 22, the infrared irradiation device 78 irradiates the metal ink 160 ejected according to the circuit pattern with infrared rays. As a result, the metal ink 160 is baked, and the wiring 162 is formed in the cavity 154. In FIG. 5, three wirings 162 are formed, and when distinguishing between the three wirings 162, the wiring on the left side in FIG. 5 is described as wiring 162a, the wiring in the center is described as wiring 162b, and the wiring on the right side is described as wiring 162c.

[0030] Next, when the wiring 162 is formed in the cavity 154 of the resin laminate 152, the stage 52 is moved below the third modeling unit 24. Then, in the third printing unit 100 of the third modeling unit 24, the dispenser 106 dispenses the conductive resin paste 166 onto both ends of the wiring 162b and onto the ends of the wiring 162a and the wiring 162c facing both ends of the wiring 162b, as shown in FIG. 6. When the conductive resin paste 166 is dispensed onto the ends of the wiring 162 in this manner, the resin laminate 152 is heated at 105 degrees for one hour by the heater 66 built into the base 60. As a result, the conductive resin paste 166 is heated through the resin laminate 152 and hardened, thereby exhibiting conductivity.

[0031] In this way, when the conductive resin paste 166 discharged onto the end of the wiring 162 is cured by heating, in the third printing unit 100, the dispenser 106 discharges the conductive resin paste 170 onto the bottom surface of the cavity 154 between the wiring 162a and the wiring 162b, that is, onto the top surface of the first laminate 156 and onto the top surface of the first laminate 156 between the wiring 162b and the wiring 162c, as shown in FIG. 7. Then, when the conductive resin paste 170 is discharged onto the top surface of the first laminate 156, the stage 52 is moved below the mounting unit 27 while the conductive resin paste 170 is not heated and is in an uncured state. In other words, the conductive resin paste 166 discharged onto the wiring 162 is heated and cured, but the conductive resin paste 170 discharged onto the first laminate 156 is not heated and is in an uncured state, and the stage 52 is moved below the mounting unit 27.

[0032] In the mounting unit 27, an electronic component 172 (see FIG. 8) is supplied by the tape feeder 134, and the electronic component 172 is held by the suction nozzle of the mounting head 136. The electronic component 172 is composed of a component body 176 and two electrodes 178 disposed on the lower surface of the component body 176. The mounting head 136 is then moved by the moving device 138, and the electronic component 172 held by the suction nozzle is mounted on the upper surface of the resin laminate 152, as shown in FIG. 8. In FIG. 8, two electronic components 172 are mounted on the upper surface of the resin laminate 152, and the two electronic components 172 are different in size. For this reason, the larger electronic component is referred to as electronic component 172a, and the smaller electronic component is referred to as electronic component 172b. Then, the two electronic components 172a and 172b are attached to the upper surface of the resin laminate 152 so that the electronic component 172a is electrically connected to the two wirings 162a and 162b, and the electronic component 172b is electrically connected to the two wirings 162b and 162c.

[0033] Specifically, the electronic component 172a is mounted so that the electrode 178 comes into contact with the conductive resin paste 166 in a cured state on the wirings 162a and 162b. At this time, the component body 176 of the electronic component 172a comes into contact with the conductive resin paste 170 in an uncured state discharged between the wirings 162a and 162b. Moreover, the electronic component 172b is mounted so that the electrode 178 comes into contact with the conductive resin paste 166 in a cured state on the wirings 162b and 162c. At this time, the component body 176 of the electronic component 172b comes into contact with the conductive resin paste 170 in an uncured state discharged between the wirings 162b and 162c. In other words, the conductive resin paste 166 is discharged at the intended position for mounting the electrode 178 on the wiring 162, and the conductive resin paste 170 is discharged at the intended position for mounting the component body 176. Therefore, when electronic component 172 is attached to resin laminate 152, electrode 178 comes into contact with hardened conductive resin paste 166 on wiring 162, and component body 176 comes into contact with unhardened conductive resin paste 170.

[0034] In this manner, by mounting the two electronic components 172a and 172b, the electronic component 172a is electrically connected to the two wirings 162a and 162b, and the electronic component 172b is electrically connected to the two wirings 162b and 162c. However, since the electronic component 172 is mounted so that the electrode 178 contacts the conductive resin paste 166 in a cured state, the contact area between the electrode 178 and the conductive resin paste 166 at this point is small. On the other hand, since the component body 176 of the electronic component 172 contacts the conductive resin paste 170 in an uncured state, the contact area between the component body 176 and the conductive resin paste 170 becomes somewhat large. Therefore, the electronic component 172 is fixed to the upper surface of the resin laminate 152 at the component body 176 by the adhesive force of the conductive resin paste 170. Then, the resin laminate 152 is heated to 105 degrees for one hour by the heater 66 built into the base 60. As a result, the conductive resin paste 170 is heated through the resin laminate 152 and hardened.

[0035] Next, the stage 52 is moved below the fourth modeling unit 25. Then, in the fourth printing section 110 of the fourth modeling unit 25, the dispenser 116 dispenses the thermosetting resin 180 between the lower surface of the component body 176 of the electronic component 172 and the upper surface of the resin laminate 152, as shown in FIG. 9. As a result, the thermosetting resin 180 is sealed between the upper surface of the resin laminate 152 and the lower surface of the component body 176 of the electronic component 172. That is, the thermosetting resin 180 is sealed between the upper surface of the resin laminate 152 and the lower surface of the component body 176. Note that the amount of the thermosetting resin 180 dispensed by the dispenser 116 is controlled so that the thermosetting resin 180 does not protrude from between the upper surface of the resin laminate 152 and the lower surface of the component body 176. Then, the resin laminate 152 is heated to 70 degrees for 30 minutes by the heater 66 built in the base 60. As a result, the thermosetting resin 180 is heated and hardened through the resin laminate 152. Note that the thermosetting resin 180 does not harden completely even when heated at 70 degrees for 30 minutes. Therefore, the thermosetting resin 180 is in a semi-hardened state at this point.

[0036] When the thermosetting resin 180 injected between the upper surface of the resin laminate 152 and the lower surface of the component body 176 is semi-cured in this manner, the stage 52 is moved below the compression unit 26. Then, in the compression section 120 of the compression unit 26, the electronic component 172 attached to the resin laminate 152 is compressed from above to below by the compression plate 122 via the rubber sheet 124, as shown in FIG. 10. During compression by the compression plate 122, the operation of the cylinder 126 is controlled, and the compression force by the compression plate 122 is set to 200 kgf. The two electronic components 172a, b are attached to the cavity 154 of the resin laminate 152, but the depth dimension of the cavity 154 is smaller than the height dimension of the two electronic components 172. Therefore, the upper surfaces of the two electronic components 172a, b extend above the cavity 154, and the two electronic components 172 can be compressed from above to below by the compression plate 122. Furthermore, as described above, the sizes of the two electronic components 172 are different, and therefore the height dimensions are also different, but a rubber sheet 124 is attached to the lower surface of the compression plate 122. As a result, when the two electronic components 172a, b are compressed, the rubber sheet 124 elastically deforms, and the two electronic components 172a, b with different height dimensions can be appropriately compressed.

[0037] In addition, while the electronic component is compressed in the compression unit 26, the resin laminate 152 is heated at 85 degrees for 45 minutes by the heater 66 built in the base 60. As a result, the thermosetting resin 180 is heated through the resin laminate 152 and hardened. The thermosetting resin 180 is completely hardened by being heated at 85 degrees for 45 minutes. As a result, the thermosetting resin 180 is completely hardened while being sealed between the upper surface of the resin laminate 152 and the lower surface of the component body 176. In addition, as the electronic component 172 is compressed, that is, as the electronic component 172 mounted on the resin laminate 152 is pressed against the resin laminate 152, the conductive resin paste 166 in contact with the electrode 178 of the electronic component 172 is deformed, and the contact area between the electrode 178 and the conductive resin paste 166 increases. In particular, the Young's modulus of the conductive resin paste 166 is low in a hardened state. The Young's modulus is a proportional constant between the amount of strain and stress in the elastic range, and is the ratio of stress to the amount of strain. Therefore, when an object with a high Young's modulus and an object with a low Young's modulus are deformed with the same stress, the object with the low Young's modulus deforms more than the object with the high Young's modulus. In other words, an object with a low Young's modulus is easily deformed. In this way, the conductive resin paste 166 with a low Young's modulus is deformed by being pressed by the electrode 178, and the contact area between the electrode 178 and the conductive resin paste 166 increases. This ensures the electrical connection between the electronic component 172 and the wiring 162. In addition, when the electronic component 172 mounted on the resin laminate 152 is pressed against the resin laminate 152, the conductive resin paste 170 in contact with the component body 176 of the electronic component 172 is also deformed, and the contact area between the component body 176 and the conductive resin paste 170 also increases. In this way, the contact area between component body 176 and conductive resin paste 170 is increased, and the adhesive strength of conductive resin paste 170 allows electronic component 172 to be suitably fixed to resin laminate 152 .

[0038] Then, when the compression by the compression plate 122 in the compression unit 26 is completed, the stage 52 is moved below the fourth modeling unit 25. Then, in the fourth printing section 110 of the fourth modeling unit 25, the dispenser 116 dispenses the thermosetting resin 190 around the electronic component 172 so as to cover the side surface of the component body 176 of the electronic component 172, as shown in FIG. 11. Then, the heater 66 built in the base 60 heats the resin laminate 152 at 85 degrees for 45 minutes. As a result, the thermosetting resin 190 is heated through the resin laminate 152 and hardened. The thermosetting resin 190 is completely hardened by being heated at 85 degrees for 45 minutes. As a result, the thermosetting resin 190 hardens in a state in which it covers the side surface of the component body 176. That is, in electronic component 172 mounted on resin laminate 152, thermosetting resins 180, 190 are enclosed between the upper surface of resin laminate 152 and the lower surface of component body 176, and harden in a state covering the side surfaces of component body 176. As a result, electronic component 172 mounted on the upper surface of resin laminate 152 is fixed by the hardened resin.

[0039] In this manner, the electronic components 172 mounted on the upper surface of the resin laminate 152 are fixed by the cured resin, and thus the circuit board 200 is formed on the heat-sensitive release film 150 on the upper surface of the base 60. Then, in order to peel off the heat-sensitive release film 150 from the formed circuit board 200, the heat-sensitive release film 150 is heated by the heater 66 built into the base 60, but at this time, the circuit board 200 is also heated, which may cause warping of the circuit board 200. For this reason, when the heat-sensitive release film 150 is heated, the heat-sensitive release film 150 is heated while the circuit board 200 is compressed.

[0040] Then, when the electronic components 172 mounted on the upper surface of the resin laminate 152 are fixed by the hardening of the thermosetting resin 190, the stage 52 is moved below the compression unit 26. Then, in the compression section 120 of the compression unit 26, as shown in FIG. 12, the entire circuit board 200 is compressed downward by the compression plate 122 via the rubber sheet 124. During compression by the compression plate 122, the operation of the cylinder 126 is controlled, and the compression force by the compression plate 122 is set to 5 kg. During compression by the compression plate 122, the heat-sensitive release film 150 is heated at 130 degrees for one hour by the heater 66 built in the base 60. This reduces the adhesiveness of the heat-sensitive release film 150, and the circuit board 200 can be easily peeled off from the base 60 together with the heat-sensitive release film 150. Then, the heat-sensitive release film 150 is peeled off from the circuit board 200, completing the formation of the circuit board 200.

[0041] By forming the circuit board 200 by such a method, the conductivity between the wiring 162 and the electrode 178 of the electronic component 172 can be appropriately ensured, compared to a circuit board formed by a conventional method. In detail, in the conventional method, after the conductive resin paste 166 is discharged onto the wiring 162, the electronic component 172 is mounted before the conductive resin paste 166 is hardened. That is, the electronic component 172 is mounted so that the electrode 178 contacts the conductive resin paste 166 in an unhardened state. Then, the conductive resin paste 166 in contact with the electrode 178 is heated and hardened. However, the conductivity of the conductive paste decreases when it is deformed or stress is applied during thermal hardening. For this reason, when a circuit board is formed by the conventional method, the conductivity between the wiring 162 and the electrode 178 of the electronic component 172 cannot be appropriately ensured.

[0042] In view of this, in the circuit forming device 10, as described above, when the conductive resin paste 166 is discharged onto the wiring 162, the conductive resin paste 166 is heated and cured before the electronic component 172 is mounted. In other words, the conductive resin paste 166 is heated and cured without being deformed or subjected to stress. This makes it possible to prevent a decrease in conductivity when the conductive resin paste 166 is cured. Then, the electronic component 172 is mounted so that the electrode 178 contacts the conductive resin paste 166 in the cured state. In this way, the conductive resin paste 166 is cured before the electronic component 172 is mounted, and the electronic component 172 is mounted so that the electrode 178 contacts the conductive resin paste 166 in the cured state, thereby appropriately ensuring the conductivity between the wiring 162 and the electronic component 172.

[0043] Furthermore, in the circuit-forming apparatus 10, when the electronic component 172 is mounted on the resin laminate 152, the compression unit 26 presses the electronic component 172 mounted on the resin laminate 152 against the resin laminate 152. At this time, the electrode 178 is pressed against the conductive resin paste 166, increasing the contact area between the electrode 178 and the conductive resin paste 166, and the electrode 178 and the conductive resin paste 166 come into close contact with each other. In this way, by increasing the contact area between the electrode 178 and the conductive resin paste 166 and bringing the electrode 178 and the conductive resin paste 166 into close contact with each other, the conductivity between the wiring 162 and the electronic component 172 can be appropriately ensured.

[0044] As described above, the circuit board 200 is formed of a plurality of materials, such as ultraviolet curing resin, metal ink, conductive resin paste, and thermosetting resin, and therefore stress is likely to occur at the connection between the electronic component 172 and the wiring 162 when the temperature changes due to differences in the linear expansion coefficients of the plurality of materials. For this reason, it is desirable to suitably fix the electronic component 172 in the resin laminate 152 in order to ensure the connection between the electronic component 172 and the wiring 162. In view of this, in the circuit forming device 10, before the electronic component 172 is mounted on the resin laminate 152, the conductive resin paste 166 in contact with the electrode 178 is heated, but the conductive resin paste 170 in contact with the component body 176 is not heated. In other words, when the electronic component 172 is mounted on the resin laminate 152, the component body 176 comes into contact with the conductive resin paste 170 in an uncured state. For this reason, the contact area between the component body 176 and the conductive resin paste 170 becomes somewhat large. As a result, electronic component 172 can be fixed to resin laminate 152 by the adhesive force of conductive resin paste 170. Furthermore, after conductive resin paste 170 is heated and hardened, electronic component 172 attached to resin laminate 152 is pressed against resin laminate 152 in compression unit 26. At this time, component body 176 is pressed against conductive resin paste 170, increasing the contact area between component body 176 and conductive resin paste 170. As a result, electronic component 172 can be further suitably fixed to resin laminate 152.

[0045] Furthermore, in electronic component 172 mounted on resin laminate 152, thermosetting resins 180, 190 are sealed between the upper surface of resin laminate 152 and the lower surface of component body 176, and are cured while covering the side surface of component body 176. This allows electronic component 172 mounted on the upper surface of resin laminate 152 to be suitably fixed by the thermosetting resin. Furthermore, when heat-sensitive peeling film 150 is heated, circuit board 200 is compressed, thereby preventing warping of circuit board 200. In this way, electronic component 172 can be suitably fixed to resin laminate 152 by preventing warping of circuit board 200.

[0046] As shown in FIG. 2, the controller 140 of the control device 28 has a resin layer forming section 210, a wiring forming section 212, a first applying section 214, a first curing section 216, a second applying section 218, a mounting section 220, a second curing section 222, an injection section 224, a third curing section 226, and a peeling section 228. The resin layer forming section 210 is a functional section for forming a resin laminate 152 with an ultraviolet curable resin. The wiring forming section 212 is a functional section for forming a wiring 162 with a metal ink 160. The first applying section 214 is a functional section for applying a conductive resin paste 166 to a planned mounting position of an electrode 178 on the wiring. The first curing section 216 is a functional section for curing the conductive resin paste 166 applied on the wiring. The second applying section 218 is a functional section for applying a conductive resin paste 170 to a planned mounting position of a component body 176. The mounting section 220 is a functional section for mounting the electronic component 172 so that the electrode 178 contacts the cured conductive resin paste 166 and the component body 176 contacts the uncured conductive resin paste 170. The second curing section 222 is a functional section for curing the conductive resin paste 170 in contact with the component body. The injection section 224 is a functional section for injecting the thermosetting resin 180 between the upper surface of the resin laminate 152 and the lower surface of the component body 176. The third curing section 226 is a functional section for curing the thermosetting resin 180 injected between the upper surface of the resin laminate 152 and the lower surface of the component body 176 while pressing the electronic component 172 against the resin laminate 152. The peeling section 228 is a functional section for heating and peeling off the heat-sensitive peeling film 150 while applying pressure to the entire circuit board 200.

[0047] In the above embodiment, the rubber sheet 124 is an example of an elastic body. The heat-sensitive release film 150 is an example of a release sheet. The resin laminate 152 is an example of a resin layer. The wiring 162 is an example of a metal wiring. The conductive resin pastes 166 and 170 are an example of a conductive fluid. The electronic component 172 is an example of an electronic component. The component body 176 is an example of a component body. The electrode 178 is an example of an electrode. The thermosetting resin 180 is an example of a curable resin. The process performed by the resin layer forming unit 210 is an example of a resin forming process. The process performed by the wiring forming unit 212 is an example of a wiring forming process. The process performed by the first applying unit 214 is an example of a first applying process. The process performed by the first curing unit 216 is an example of a first curing process. The process performed by the second applying unit 218 is an example of a second applying process. The process performed by the mounting unit 220 is an example of a mounting process. The process performed by second curing unit 222 is an example of a second curing process. The process performed by injection unit 224 is an example of an injection process. The process performed by third curing unit 226 is an example of a third curing process. The process performed by peeling unit 228 is an example of a peeling process.

[0048] The present invention is not limited to the above embodiment, and can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. For example, in the above embodiment, the thermosetting resin is discharged between the upper surface of the resin laminate 152 and the lower surface of the component body 176 of the electronic component 172. If the thermosetting resin overflows between the upper surface of the resin laminate 152 and the lower surface of the component body 176, it is desirable to suck up the overflowing thermosetting resin. The thermosetting resin may be sucked up manually by an operator or automatically by a sucking device or the like.

[0049] In the above embodiment, the circuit board is compressed by the compression plate 122 via the rubber sheet 124, but the circuit board may be compressed by the compression plate 122 via various members as long as the members are elastically deformable. For example, silicon-based resin, urethane-based resin, etc. can be used as the elastically deformable member.

[0050] In addition, in the above embodiment, the conductive resin paste 166 is used as the fluid that electrically connects the wiring 162 and the electrode 178 of the electronic component 172, but various fluids can be used as long as they exhibit conductivity.

[0051] In the above embodiment, ultraviolet curable resin and thermosetting resin are used as the curable resin, but two-liquid mixed curable resin, thermoplastic resin, etc. may be used. In the above embodiment, ultraviolet curable resin is used as the resin forming the resin laminate 152, and thermosetting resin is used as the resin fixing the lower surface and periphery of the electronic component 172. In other words, the resin forming the resin laminate 152 and the resin fixing the lower surface and periphery of the electronic component 172 are different thermosetting resins, but the resin forming the resin laminate 152 and the resin fixing the lower surface and periphery of the electronic component 172 may be the same thermosetting resin.

[0052] Furthermore, in the above embodiment, the conductive resin paste is dispensed by the dispenser 106, but it may be transferred by a transfer device or the like. Also, the conductive resin paste may be printed by screen printing. [Explanation of symbols]

[0053] 124: rubber sheet (elastic body), 150: heat-sensitive release film (release sheet), 152: resin laminate (resin layer), 162: wiring (metal wiring), 166: conductive resin paste (conductive fluid), 170: conductive resin paste (conductive fluid), 172: electronic component, 176: component body, 178: electrode, 180: thermosetting resin (curable resin), 210: resin layer forming section (resin layer forming step), 212: wiring forming section (wiring forming step), 214: first application section (first application step), 216: first curing section (first curing step), 218: second application section (second application step), 220: mounting section (mounting step), 222: second curing section (second curing step), 224: injection section (injection step), 226: third curing section (third curing step), 228: peeling section (peeling step)

Claims

1. a wiring forming step of forming metal wiring on the resin layer; a first application step of applying a conductive fluid to a position on the metal wiring where an electrode of an electronic component is to be mounted, using a dispenser; a first curing step of curing the conductive fluid applied in the first application step; a second application step of applying a conductive fluid to a position on the resin layer where a component body of the electronic component is to be mounted by the dispenser; a mounting step of mounting the electronic component such that the electrode contacts the conductive fluid that has been hardened in the first hardening step and the component body contacts the conductive fluid that has been applied in the second application step and has not been hardened; a second curing step of curing the conductive fluid applied in the second application step after the electronic component is mounted in the mounting step; A method for forming an electric circuit comprising the steps of:

2. an injection step of injecting a curable resin between the electronic component and the resin layer after the conductive fluid is cured in the second curing step; a third curing step of curing the curable resin while pressing the electronic component against the resin layer after the curable resin is injected in the injection step; The method of claim 1 , further comprising:

3. The third curing step comprises:

3. The method for forming an electric circuit according to claim 2, wherein the hardening resin is hardened while a plate-like elastic body is placed on the electronic component and the electronic component is pressed against the resin layer via the elastic body.

4. a compression step of pressing the electronic component against the resin layer after the conductive fluid is cured in the second curing step, 2. The method for forming an electrical circuit according to claim 1, wherein the conductive fluid has a Young's modulus low enough that, in its hardened state, the conductive fluid is deformed by being pressed by the electrode in the compression step, thereby increasing the contact area between the electrode and the conductive fluid.

5. a resin layer forming step of forming the resin layer on a release sheet that is peeled off by heating; a peeling step of heating the release sheet while applying pressure to the entire resin layer after the circuit is formed, to peel off the release sheet from the resin layer; The method for forming an electric circuit according to any one of claims 1 to 4, further comprising the steps of:

6. a first modeling unit that ejects metal ink to model metal wiring; a second modeling unit that ejects a curable resin to model a resin layer; a third modeling unit having a dispenser that dispenses a conductive fluid; A heater and Equipped with The resin layer is formed by the second modeling unit, forming a metal wiring on the resin layer by the first modeling unit; applying the conductive fluid to a position on the metal wiring where an electrode of an electronic component is to be attached by the dispenser; The conductive fluid applied onto the metal wiring is hardened by the heater; applying a conductive fluid to a position on the resin layer where a component body of the electronic component is to be mounted by the dispenser; An electrical circuit forming apparatus which hardens the conductive fluid on the resin layer while the electronic component is mounted such that the electrode contacts the hardened conductive fluid on the metal wiring and the component body contacts the unhardened conductive fluid on the resin layer.

7. a mounting unit for mounting the electronic component, 7. The electrical circuit forming apparatus according to claim 6, wherein the mounting unit mounts the electronic component such that the electrode contacts the hardened conductive fluid on the metal wiring and the component body contacts the unhardened conductive fluid on the resin layer.

8. The compression unit further includes a plate-shaped elastic body. After the conductive fluid on the resin layer is hardened, the compression unit presses the electronic component against the resin layer via the elastic body in a state in which the elastic body is placed on the mounted electronic component; 8. The electrical circuit forming device according to claim 6, wherein the conductive fluid has a Young's modulus low enough that, in a hardened state, the conductive fluid is deformed by being pressed against the electrodes by the compression unit, thereby increasing the contact area between the electrodes and the conductive fluid.

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