Circuit formation method and circuit formation device

Abstract

Provided is a circuit formation method comprising: a wiring formation step for forming wiring with a metal-containing liquid on an upper surface of a resin layer; a protrusion formation step for forming a protrusion with a curable resin at a position planned for mounting a component body of an electronic component to the upper surface of the resin layer; and a mounting step for mounting the electronic component to the upper surface of the resin layer such that an electrode provided to a lower surface of the component body in an inclined state contacts the wiring and the component body contacts the protrusion, wherein in the protrusion formation step, the protrusion is formed to a height which causes the lower surface of the component body to be inclined such that, when the electronic component is mounted to the upper surface of the resin layer in the mounting step, the inclination of the lower surface of the electrode with respect to the upper surface of the resin layer decreases.

Description

Circuit forming method and circuit forming device

[0001] The present invention relates to a circuit forming method and a circuit forming apparatus for mounting electronic components so that electrodes come into contact with wiring.

[0002] Japanese Patent Application Laid-Open No. 2003-144992 discloses a technique for mounting an electronic component so that the electrodes come into contact with the wiring.

[0003] JP 2019-176056 Public Relations

[0004] Some electronic components have electrodes disposed at an angle on the underside of the component body. The objective is to mount such an electronic component so that the electrodes of the electronic component are in proper contact with the wiring.

[0005] In order to solve the above problems, this specification discloses a circuit formation method including a wiring formation step of forming wiring on the upper surface of a resin layer using a metal-containing liquid, a protrusion formation step of forming protrusions using a curable resin at planned positions for mounting the component body of an electronic component on the upper surface of the resin layer, and a mounting step of mounting the electronic component on the upper surface of the resin layer so that electrodes arranged at an angle on the lower surface of the component body come into contact with the wiring and the component body comes into contact with the protrusions, wherein the protrusion formation step forms the protrusions at a height that tilts the lower surface of the component body so that the inclination of the lower surface of the electrode relative to the upper surface of the resin layer is reduced when the electronic component is mounted on the upper surface of the resin layer in the mounting step.

[0006] The present specification also discloses a circuit forming apparatus that includes a metal-containing liquid discharging device that discharges a metal-containing liquid, a resin discharging device that discharges a curable resin, a mounting device that performs mounting work of electronic components, and a control device, wherein the control device performs a wiring forming process in which wiring is formed by discharging the metal-containing liquid onto the upper surface of a resin layer using the metal-containing liquid discharging device, a protrusion forming process in which protrusions are formed by discharging the curable resin using the resin discharging device at a planned mounting position of a component body of the electronic component on the upper surface of the resin layer, and a mounting process in which the mounting device mounts the electronic component on the upper surface of the resin layer so that electrodes arranged at an angle on the lower surface of the component body come into contact with the wiring and the component body comes into contact with the protrusions, and the protrusion forming process forms the protrusions at a height that tilts the lower surface of the component body so that when the electronic component is mounted on the upper surface of the resin layer in the mounting process, the inclination of the lower surface of the electrode with respect to the upper surface of the resin layer is reduced.

[0007] In the present disclosure, protrusions are formed from a curable resin at positions where the component body of the electronic component is to be mounted on the upper surface of the resin layer, and the electronic component is mounted on the upper surface of the resin layer so that the electrodes, which are arranged at an angle on the lower surface of the component body, come into contact with the wiring and the component body comes into contact with the protrusions. Furthermore, when the electronic component is mounted on the upper surface of the resin layer, the protrusions are formed to a height that tilts the lower surface of the component body so that the inclination of the lower surfaces of the electrodes relative to the upper surface of the resin layer is reduced. This allows the electronic component to be mounted so that the tilted electrodes come into appropriate contact with the wiring.

[0008] 1 is a diagram showing an example of a circuit forming apparatus; FIG. 2 is a block diagram showing an example of a control device; FIG. 3 is a cross-sectional view showing an example of a circuit board with a resin laminate formed thereon; FIG. 4 is a cross-sectional view showing an example of a circuit board with wiring formed on the resin laminate; FIG. 5 is a cross-sectional view showing an example of a circuit board with a second resin laminate formed on the resin laminate; FIG. 6 is a cross-sectional view showing an example of a circuit board with bumps formed on the wiring; FIG. 7 is a cross-sectional view showing an example of a circuit board with thermosetting resin dispensed onto the resin laminate; FIG. 8 is a cross-sectional view showing an example of a circuit board with an electronic component mounted thereon; FIG. 9 is a side view showing an example of an electronic component comprising electrodes disposed at an incline on the underside of a component body; FIG. 10 is a cross-sectional view showing an example of a circuit board with an electronic component pressed against the resin laminate; FIG. 11 is a cross-sectional view showing an example of a circuit board with thermosetting resin dispensed into a cavity; FIG. 12 is a side view showing an example of an electronic component with a small contact area between the electrodes and the bumps; FIG. 13 is a cross-sectional view showing an example of a circuit board with protrusions formed at planned mounting positions on the component body of the electronic component; FIG. 14 is a bottom view showing an example of an electronic component with electrodes disposed at an incline on the underside of a component body. FIG. 1 is a diagram showing an example of a circuit board in a state where a protrusion is formed at a planned mounting position of a component body of an electronic component, as viewed from above. FIG. 1 is a diagram showing an example of a circuit board in a state where a bump is formed on a wiring, as viewed from above. FIG. 2 is a diagram showing an example of a circuit board in a state where a thermosetting resin is dispensed onto a resin laminate, as viewed from above. A cross-sectional view showing an example of a circuit board in a state where an electronic component is mounted. A cross-sectional view showing an example of a circuit board in a state where an electronic component is pressed against the resin laminate. A side view showing an example of an electronic component mounted so that the lower surface of the electrode and the upper surface of the resin laminate are parallel. A cross-sectional view showing an example of a circuit board in a state where a thermosetting resin is dispensed inside a cavity. A cross-sectional view showing an example of a circuit board in a state where a protrusion is formed together with the resin laminate. A diagram showing an example of a circuit board in a state where a plurality of protrusions are formed on the resin laminate, as viewed from above.

[0009] 1 shows an example of 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 pressing 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 pressing unit 26, and the mounting unit 27 are arranged on a base 29 of the circuit forming apparatus 10. The base 29 has a generally rectangular shape, and in the following description, the longitudinal direction of the base 29 will be referred to as the X-axis direction, the lateral direction of the base 29 as the Y-axis direction, and the direction perpendicular to both the X-axis direction and the Y-axis direction as the Z-axis direction.

[0010] 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 the 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 also includes an electromagnetic motor (see FIG. 2) 38, which is driven to move the X-axis slider 36 to any position in the X-axis direction. The Y-axis slide mechanism 32 also 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. A stage 52 is held on 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 any position in the Y-axis direction by driving the electromagnetic motor 56. As a result, the stage 52 moves to any position on the base 29 by driving the X-axis slide mechanism 30 and the Y-axis slide mechanism 32.

[0011] The stage 52 has a base 60, a holding device 62, an elevating 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 holding devices 62 clamp both edges of the substrate placed on the base 60 in the X-axis direction, thereby fixedly holding the substrate. The elevating 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.

[0012] The first modeling unit 22 is a unit that models the wiring of a circuit board and includes a first printing unit 72 and a baking unit 74. The first printing unit 72 includes an inkjet head 76 (see FIG. 2 ) that ejects metal ink in a linear pattern. The metal ink is a dispersion of fine particles (e.g., nanometer-sized metal fine particles) of a metal (e.g., silver) in a solvent. The surfaces of the metal fine particles are coated with a dispersant to prevent aggregation in the solvent. The inkjet head 76 ejects the metal ink from multiple nozzles using, for example, a piezoelectric method using piezoelectric elements.

[0013] 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. The metal ink irradiated with infrared rays is baked, forming wiring. Note that baking of metal ink is a phenomenon in which, by applying energy, the solvent is vaporized and the protective film on 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.

[0014] The second modeling unit 23 is a unit that models the resin layer of the circuit board, and includes a second printing unit 84 and a curing unit 86. The second printing unit 84 includes an inkjet head 88 (see FIG. 2 ) that ejects ultraviolet curable resin. The ultraviolet curable resin is a resin that hardens when irradiated with ultraviolet light. The inkjet head 88 may be, for example, a piezo-type inkjet head using a piezoelectric element, or a thermal-type inkjet head that heats the resin to generate bubbles and ejects the resin from multiple nozzles.

[0015] The curing unit 86 has a planarizing device (see FIG. 2) 90 and an irradiation device (see FIG. 2) 92. The planarizing device 90 flattens the top surface of the UV-curable resin ejected by the inkjet head 88. For example, the planarizing device 90 makes the thickness of the UV-curable resin uniform by leveling the surface of the UV-curable resin and scraping off excess resin with a roller or blade. The irradiation device 92 is equipped with a mercury lamp or LED as a light source and irradiates the ejected UV-curable resin with ultraviolet light. This hardens the ejected UV-curable resin, forming a resin layer.

[0016] The third modeling unit 24 is a unit that models connection portions between electrodes and wiring of electronic components on a circuit board, and includes a third printing unit 100. The third printing unit 100 includes a dispenser 106 (see FIG. 2 ), which dispenses conductive paste. The conductive paste is made by dispersing metal particles in a resin that hardens when heated at a relatively low temperature. The metal particles in the conductive paste are smaller than the metal microparticles in metal ink. The conductive paste contains, for example, micrometer-sized metal particles. The metal particles are flake-shaped, and the viscosity of the conductive paste is relatively high compared to that of metal ink.

[0017] The conductive paste dispensed by the dispenser 106 is then heated by the heater 66 built into the base 60. The resin in the heated conductive paste hardens. At this time, the resin in the conductive paste hardens and shrinks, causing the flake-shaped metal particles dispersed in the resin to come into contact with each other. This allows the conductive paste to exhibit conductivity. The resin in the conductive paste is an organic adhesive, and exhibits adhesive strength when hardened by heating.

[0018] The fourth modeling unit 25 is a unit that models resin for fixing electronic components to a circuit board, and includes a fourth printing unit 110. The fourth printing unit 110 includes a dispenser 116 (see FIG. 2 ) that dispenses thermosetting resin. Thermosetting resin is a resin that hardens when heated. The dispenser 116 uses, for example, an air pulse method that uses compressed air. The thermosetting resin dispensed by the dispenser 116 is heated by a heater 66 built into the base 60 and hardens.

[0019] The pressing unit 26 is a unit for pressing the circuit board and includes a pressing section 120. The pressing section 120 includes a pressing plate (see FIG. 10) 122, a rubber plate (see FIG. 10) 124, and a cylinder (see FIG. 2) 126. The rubber plate 124 is molded from, for example, silicone rubber and has a plate shape. The pressing plate 122 is molded from, for example, steel and has a plate shape. The rubber plate 124 is attached to the underside of the pressing plate 122. The pressing plate 122 is pressed against the circuit board by the operation of the cylinder 126. As a result, the circuit board is pressed by the pressing plate 122 via the rubber plate 124. By controlling the operation of the cylinder 126, the force pressing the board can be controllably changed. The base 60 held by the holding device 62 may be raised by the lifting device 64, thereby pressing the pressing plate 122 relatively against the circuit board placed on the base 60. Alternatively, the cylinder 126 may be actuated to press the pressing plate 122 against the circuit board, and the base 60 held by the holding device 62 may be raised by the lifting device 64, thereby pressing the pressing plate 122 relatively against the circuit board placed on the base 60.

[0020] The mounting unit 27 is a unit that mounts electronic components on a circuit board and includes a supply unit 130 and a mounting unit 132. The supply unit 130 includes, for example, a plurality of tape feeders 134 (see FIG. 2 ) that feed taped electronic components one by one, and supplies the electronic components at a supply position. Note that the supply unit 130 is not limited to the tape feeders 134, and may also be a tray-type supply device that picks up and supplies electronic components from a tray. The supply unit 130 may also be configured to include both tape-type and tray-type supply devices, or other types of supply devices.

[0021] The mounting unit 132 has a mounting head 136 (see FIG. 2) and a moving device 138 (see FIG. 2). The mounting head 136 has a suction nozzle (not shown) for suctioning and holding electronic components. The suction nozzle sucks and holds electronic components by air when negative pressure is supplied from a positive / negative pressure supply device (not shown). The positive / negative pressure supply device then supplies a slight positive pressure to the suction nozzle, which then releases the electronic component. The moving device 138 also moves the mounting head 136 between the position where electronic components are supplied by the tape feeder 134 and the circuit board placed on the base 60. As a result, in the mounting unit 132, electronic components supplied from the tape feeder 134 are held by the suction nozzle, and the electronic components held by the suction nozzle are mounted onto the circuit board.

[0022] 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 dispensers 106, 116, the cylinder 126, the tape feeder 134, the mounting head 136, and the moving device 138. The controller 140 includes a CPU, ROM, RAM, etc., and is primarily a computer, and is connected to the plurality of drive circuits 142. As a result, the controller 140 controls 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 pressing unit 26, and the mounting unit 27.

[0023] In the circuit forming apparatus 10, a resin laminate is formed on the base 60 using the above-described configuration, and wiring is formed on the upper surface of the resin laminate. Then, electrodes of electronic components are electrically connected to the wiring via the conductive paste, and the electronic components are fixed with resin, thereby forming a circuit board.

[0024] An example of a process for forming a circuit board will be described. Specifically, first, 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 base 60 of the stage 52, as shown in FIG. 3 . The resin laminate 152 is formed by repeatedly discharging an ultraviolet curable resin from the inkjet head 88 and irradiating the discharged ultraviolet curable resin with ultraviolet light by the irradiation device 92.

[0025] More specifically, in the second printing unit 84 of the second modeling unit 23, the inkjet head 88 ejects a thin film of ultraviolet curable resin onto the upper surface of the base 60. Then, after the ultraviolet curable resin has been ejected in the form of a thin film, the ultraviolet curable resin is flattened by a flattening device 90 in the curing unit 86 so that the film thickness of the ultraviolet curable resin becomes uniform. Then, the irradiation device 92 irradiates the thin film of ultraviolet curable resin with ultraviolet rays. As a result, a thin film resin layer 153 is formed on the base 60.

[0026] Next, the inkjet head 88 ejects a thin film of ultraviolet curable resin onto the thin film resin layer 153. The thin film of ultraviolet curable resin is then flattened by a flattening device 90, and an irradiation device 92 irradiates the ejected thin film of ultraviolet curable resin with ultraviolet light, thereby laminating thin film resin layers 153 on thin film resin layers 153. In this manner, the ejection of ultraviolet curable resin onto the thin film resin layer 153 and the irradiation with ultraviolet light are repeated, and a plurality of resin layers 153 are laminated, thereby forming a resin laminate 152.

[0027] Next, once the resin laminate 152 is formed, the stage 52 is moved below the first modeling unit 22. Then, in the first printing unit 72 of the first modeling unit 22, the inkjet head 76 ejects metal ink 160 in a line shape according to the circuit pattern onto the upper surface of the resin laminate 152, as shown in FIG. 4 . Subsequently, in the baking unit 74 of the first modeling unit 22, the infrared irradiation device 78 irradiates infrared rays onto the metal ink 160 ejected according to the circuit pattern. As a result, the metal ink 160 is baked, and wiring 162 is formed on the upper surface of the resin laminate 152.

[0028] Next, once the wiring 162 has been formed on the resin laminate 152, it is moved below the second modeling unit 23. Then, in the second modeling unit 23, the inkjet head 88 ejects the ultraviolet curable resin in the form of a thin film so that the ends of the wiring 162 are exposed. Next, once the ultraviolet curable resin has been ejected in the form of a thin film, the ultraviolet curable resin is flattened in the curing section 86 so that the film thickness of the ultraviolet curable resin becomes uniform. Then, the irradiation device 92 irradiates the thin film of ultraviolet curable resin with ultraviolet rays. As a result, a resin layer 156 is formed on the resin laminate 152, as shown in FIG. 5 .

[0029] Next, the inkjet head 88 ejects a thin film of ultraviolet curable resin only onto the resin layer 156. That is, the inkjet head 88 ejects the ultraviolet curable resin onto the resin layer 156 so that the ends of the wiring 162 are exposed. The thin film of ultraviolet curable resin is then flattened by the planarization device 90, and the irradiation device 92 irradiates the ejected thin film of ultraviolet curable resin with ultraviolet light, thereby laminating a resin layer 156 on top of the resin layer 156. In this manner, the ejection of ultraviolet curable resin onto the resin layer 156 and the irradiation of ultraviolet light are repeated, laminating a plurality of resin layers 156, thereby forming a resin laminate 157. As a result, the resin laminate 157 is formed on top of the resin laminate 152, and the step between the resin laminate 152 and the resin laminate 157 functions as the cavity 154.

[0030] Once the resin laminate 157 is formed on the resin laminate 152 in this manner, 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 conductive paste 166 onto the end of the wiring 162 exposed inside the cavity 154, as shown in FIG. 6 . Once the conductive paste 166 is dispensed onto the end of the wiring 162 in this manner, the heater 66 built into the base 60 heats the resin laminate 152. At this time, the conductive paste 166 is heated via the resin laminate 152 and hardens. As a result, the conductive paste 166 exhibits conductivity. Note that the hardened conductive paste 166 functions as a bump, and therefore the hardened conductive paste 166 is referred to as a bump 168.

[0031] Once the bumps 168 are formed on the ends of the wiring 162 in this manner, 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 170 onto the upper surface of the resin laminate 152 so that the thermosetting resin 170 extends from the ends of the wiring 162 inside the cavity 154, as shown in FIG.

[0032] Once the thermosetting resin 170 has been dispensed onto the upper surface of the resin laminate 152, the stage 52 is moved below the mounting unit 27. In the mounting unit 27, for example, an electronic component 172 (see FIG. 8 ) is supplied by a tape feeder 134, and the electronic component 172 is held by a suction nozzle of the mounting head 136. The electronic component 172 is composed of a component body 176 and an electrode 178 disposed on the underside of the component body 176. As shown in FIG. 9 , the underside of the component body 176 is flat except for one side edge 179 of a pair of opposing side edges. The one side edge 179 forms an inclined surface 180 that is inclined relative to the underside of the component body 176. The inclined surface 180 is inclined in a direction recessed from the underside of the component body 176. A flat electrode 178 is disposed on the inclined surface 180. That is, in the electronic component 172, the electrodes 178 are disposed in a state inclined with respect to the lower surface of the component body 176. The inclination angle of the electrodes 178 with respect to the lower surface of the component body 176 is α.

[0033] An electronic component 172 having such a shape is held by a suction nozzle, and the mounting head 136 is moved by the moving device 138, whereby the electronic component 172 held by the suction nozzle is mounted so as to be electrically connected to the wiring 162, as shown in FIG. 8 . At this time, the electronic component 172 is mounted so that the component body 176 faces the thermosetting resin 170 and the electrodes 178 face the bumps 168. Note that the bottom surface of the component body 176 is in close contact with the thermosetting resin, but the electrodes 178 are inclined and do not come into contact with the bumps 168. Alternatively, the electrodes 178 may come into slight contact with the upper ends of the bumps 168. In other words, the conductive paste 166 is dispensed at the intended mounting position of the electrodes 178 on the wiring 162, and the thermosetting resin 170 is dispensed at the intended mounting position of the component body 176.

[0034] Once the electronic component 172 has been mounted in this manner, the stage 52 is moved below the pressing unit 26. Then, in the pressing section 120 of the pressing unit 26, as shown in FIG. 10 , the electronic component 172 mounted on the resin laminate 152 is pressed from above downward by the pressing plate 122 via the rubber plate 124. That is, the electronic component 172 is pressed against the resin laminate 152 by the rubber plate 124. Note that the rubber plate 124 deforms when the electronic component 172 is pressed by the rubber plate 124, and thus the electronic component 172 is appropriately pressed against the resin laminate 152.

[0035] Furthermore, while the electronic component is being pressed by the pressing unit 26, the heater 66 built into the base 60 heats the resin laminate 152. As a result, the thermosetting resin 170 is heated and hardened through the resin laminate 152. In this manner, when the electronic component 172 is pressed against the resin laminate 152 by the rubber plate 124, the component body 176 and the thermosetting resin 170 come into close contact with each other, and the electrodes 178 come into contact with the bumps 168. As a result, the adhesive force of the thermosetting resin 170 fixes the electronic component 172 to the upper surface of the resin laminate 152 at the component body 176, and the contact between the electrodes 178 and the bumps 168 electrically connects the electronic component 172 to the wiring 162.

[0036] Then, when the pressing unit 26 completes pressing, the stage 52 is moved below the fourth modeling unit 25. Then, in the fourth printing unit 110 of the fourth modeling unit 25, the dispenser 116 dispenses the thermosetting resin 182 around the electronic component 172 so as to cover the side surfaces of the component body 176 of the electronic component 172, as shown in FIG. 11 . Then, the heater 66 built into the base 60 heats the resin laminate 152. This heats and hardens the thermosetting resin 182 through the resin laminate 152. This causes the thermosetting resin 182 to harden while covering the side surfaces of the component body 176. That is, in the electronic component 172 mounted on the resin laminate 152, the thermosetting resin 170 hardens while in close contact with the lower surface of the component body 176, and the thermosetting resin 182 hardens while covering the side surfaces of the component body 176. As a result, the electronic components 172 mounted on the upper surface of the resin laminate 152 are fixed by the hardened resin, thereby forming the circuit 190 .

[0037] In the circuit 190 formed in this manner, the electronic component 172 is pressed against the resin laminate 152 by the rubber plate 124, thereby bringing the electrodes 178 into contact with the bumps 168. However, because the electrodes 178 are inclined, there is a risk that the electrodes 178 and the bumps 168 will not come into close contact with each other, resulting in poor electrical continuity. Specifically, when the electronic component 172 is pressed against the resin laminate 152, as shown in FIG. 12 , the entire lower surface of the component body 176 comes into close contact with the thermosetting resin 170, compressing the thermosetting resin 170. However, because the electrodes 178 are inclined so as to be recessed relative to the lower surface of the component body 176, only a portion of the electrodes 178 near the lower surface of the component body 176 comes into contact with the bumps 168, even when the electronic component 172 is pressed against the resin laminate 152. As a result, only a portion of the electrodes 178 can compress the bumps 168, reducing the contact area between the electrodes 178 and the bumps 168 and resulting in poor electrical continuity.

[0038] In consideration of this, protrusions are formed on the upper surface of the resin laminate 152 so as to reduce the inclination of the lower surface of the electrode 178 relative to the upper surface of the resin laminate 152, and the electronic component 172 is tilted, thereby increasing the contact area between the electrode 178 and the bump 168. Specifically, when the wiring 162 is formed on the resin laminate 152, a resin laminate 157 is formed on the resin laminate 152 as shown in FIG. 13 , and a protrusion 200 is also formed along with the resin laminate 157. Specifically, when the resin laminate 157 is formed on the resin laminate 152, the protrusion 200 is formed on the resin laminate 152 inside the cavity 154 of the resin laminate 157. The protrusion 200 is formed at a position where the component main body 176 is to be mounted when the electronic component 172 is mounted on the resin laminate 152. The height dimension A of the protrusion 200 is set in advance, and the protrusion 200 is formed with the set height dimension. The height dimension A of the protrusion 200 will be described later.

[0039] 14 , the electronic component 172 includes a plurality of (e.g., four) electrodes 178, which are arranged at equal intervals on an inclined surface 180 of the component body 176. As described above, the lower surface of the component body 176 is flat except for one side edge 179 of a pair of opposing side edges, and this one side edge 179 is an inclined surface 180 that is inclined relative to the lower surface of the component body 176. The plurality of electrodes 178 are arranged at equal intervals on this inclined surface 180 along the direction in which this one side edge 179 extends.

[0040] 15 , a plurality of (e.g., four) wires 162 are formed on the resin laminate 152 on which the electronic component 172 having a plurality of electrodes 178 is mounted, at positions corresponding to the plurality of (e.g., four) electrodes 178. The ends of the plurality of wires 162 are the intended mounting positions for the plurality of electrodes 178. Furthermore, a protrusion 200 is formed along the extension direction of one of the pair of side edges of the component body 176, at the intended mounting position on the side of the other side edge 202 opposite to the one side edge 179 on which the electrodes 178 are arranged.

[0041] Once the protrusions 200 are formed on the resin laminate 152 in this manner, in the third modeling unit 24, as shown in Fig. 16 , conductive paste 166 is dispensed onto the ends of each wiring 162. Then, the resin laminate 152 is heated by the heater 66, whereby the conductive paste 166 hardens and bumps 168 are formed on the ends of each wiring 162. Subsequently, in the fourth modeling unit 25, as shown in Fig. 17 , thermosetting resin 170 is dispensed onto the upper surface of the resin laminate 152 between each bump 168 and the protrusions 200.

[0042] 18 , in the mounting unit 27, the electronic component 172 is mounted so that the electrodes 178 contact the bumps 168 and the component body 176 contacts the protrusions 200. Note that the mounting head 136 holds the electronic component 172 so that the bottom surface of the component body 176 is horizontal, but when the electronic component 172 is mounted, the bottom surface of the component body 176 comes into contact with the protrusions 200, causing the bottom surface of the component body 176 to tilt and bringing the electrodes 178 into contact with the bumps 168.

[0043] 19 , in the pressing unit 26, the electronic component 172 mounted on the resin laminate 152 is pressed from above downward by the pressing plate 122 via the rubber plate 124. That is, the electronic component 172 is pressed against the resin laminate 152 by the rubber plate 124. Note that, because the rubber plate 124 deforms when the electronic component 172 is pressed by the rubber plate 124, the electronic component 172 can be pressed appropriately against the resin laminate 152 even if it is mounted at an angle.

[0044] Furthermore, while the electronic component is being pressed by the pressing unit 26, the heater 66 built into the base 60 heats the resin laminate 152. This heats and hardens the thermosetting resin 170 through the resin laminate 152. At this time, the electronic component 172 is pressed against the resin laminate 152 by the rubber plate 124, so that, as shown in FIG. 20 , the lower surface of the electrode 178 becomes parallel to the upper surface of the resin laminate 152, and the entire electrode 178 comes into close contact with the bump 168, uniformly compressing the bump 168. This increases the contact area between the electrode 178 and the bump 168, thereby ensuring appropriate electrical continuity between the electrode 178 and the bump 168. Furthermore, the lower surface of the component body 176 comes into close contact with the thermosetting resin 170, and the adhesive force of the thermosetting resin 170 fixes the electronic component 172 to the upper surface of the resin laminate 152 at the component body 176.

[0045] In this way, when electronic component 172 is pressed against resin laminate 152, the lower surface of electrode 178 becomes parallel to the upper surface of resin laminate 152, and the entire electrode 178 comes into close contact with bump 168, uniformly compressing bump 168 and ensuring electrical continuity between electrode 178 and bump 168. For this reason, height dimension A of protrusion 200 is set so that the lower surface of electrode 178 becomes parallel to the upper surface of resin laminate 152 when electronic component 172 is pressed. More specifically, when electronic component 172 is pressed against resin laminate 152, bump 168 is compressed by electrode 178, and the height dimension of bump 168 after compression is calculated based on the discharge amount of bump 168. Then, height dimension A of protrusion 200 is calculated based on the inclination angle α of electrode 178 (see FIG. 9 ) and the height dimension of bump 168 after compression. At this time, the height dimension A of the protrusion 200 is calculated so that the lower surface of the electrode 178 is parallel to the upper surface of the resin laminate 152. By setting the height dimension A calculated in this manner as the height dimension A of the protrusion 200 and forming the protrusion 200 at the intended mounting position on the component main body 176, the lower surface of the electrode 178 can be made parallel to the upper surface of the resin laminate 152 when the electronic component 172 is pressed against the resin laminate 152. It is desirable to consider not only the inclination angle α of the electrode 178 and the height dimension of the bump 168 after compression, but also the dimensions of the electronic component 172 and the position where the protrusion 200 is formed.

[0046] After the electronic component 172 is pressed against the resin laminate 152, the electrodes 178 and the bumps 168 come into close contact with each other, and the lower surface of the component body 176 is fixed to the resin laminate 152 by the adhesive force of the thermosetting resin 170, the fourth modeling unit 25 ejects a thermosetting resin 182 around the electronic component 172, as shown in FIG. 21 . The resin laminate 152 is then heated by the heater 66 built into the base 60. This heats the thermosetting resin 182 through the resin laminate 152, causing it to harden. The electronic component 172 mounted on the upper surface of the resin laminate 152 is fixed by the hardened resin in this manner, thereby forming a circuit 210.

[0047] 2, the controller 140 of the control device 28 has a wiring forming section 220, a protrusion forming section 222, a bump forming section 224, an attachment section 226, and a pressing section 228. The wiring forming section 220 is a functional section for forming the wiring 162 on the resin laminate 152. The protrusion forming section 222 is a functional section for forming the protrusion 200 on the resin laminate 152. The bump forming section 224 is a functional section for forming the bump 168 on the wiring 162. The attachment section 226 is a functional section for attaching the electronic component 172 so that the electrode 178 contacts the bump 168 and the component body 176 contacts the protrusion 200. The pressing section 228 is a functional section for pressing the electronic component 172 against the resin laminate 152.

[0048] In the above embodiment, the circuit forming device 10 is an example of a circuit forming device. The control device 28 is an example of a control device. The inkjet head 76 is an example of a metal-containing liquid ejection device. The inkjet head 88 is an example of a resin ejection device. The mounting unit 132 is an example of a mounting device. The resin laminate 152 is an example of a resin layer. The metal ink 160 is an example of a metal-containing liquid. The wiring 162 is an example of a wiring. The conductive paste 166 is an example of a conductive fluid. The bump 168 is an example of a connection portion. The electronic component 172 is an example of an electronic component. The component body 176 is an example of a component holder. The electrode 178 is an example of an electrode. The protrusion 200 is an example of a protrusion. Furthermore, the processes and treatments performed by the wiring forming unit 220 are examples of a wiring forming process and a wiring forming treatment. The processes and treatments performed by the protrusion forming unit 222 are examples of a protrusion forming process and a protrusion forming treatment. The process performed by the bump forming unit 224 is an example of a connection forming process. The process and processing performed by the mounting unit 226 are an example of a mounting process and a mounting treatment. The process performed by the pressing unit 228 is an example of a pressing process.

[0049] As described above, the present embodiment has the following advantages.

[0050] The height dimension of the protrusion 200 is set so that when the electronic component 172 is mounted on the upper surface of the resin laminate 152, the lower surface of the electrode 178 is parallel to the upper surface of the resin laminate 152. This increases the contact area between the electrode 178 and the bump 168, making it possible to properly ensure electrical continuity between the electrode 178 and the bump 168.

[0051] Furthermore, the electrode 178 is disposed on one side edge 179 of a pair of opposing side edges on the underside of the component body 176, and the protrusion 200 is formed at a planned mounting position on the other side edge 202 of the pair of opposing side edges on the underside of the component body 176. This allows the electronic component 172 to be tilted in a suitable manner.

[0052] Furthermore, the protrusion 200 is formed on the side of the other of a pair of opposing side edges 202 on the underside of the component body 176, along the extending direction of that side edge 202. This allows the protrusion 200 to properly support the electronic component 172 in a tilted state, preventing the electronic component 172 from rattling.

[0053] Furthermore, the height dimension of the protrusion 200 is set in accordance with the inclination angle α of the electrode 178 and the height dimension of the compressed bump 168. This allows the inclination angle of the electrode 178 with respect to the resin laminate 152 to be appropriately reduced.

[0054] The present invention is not limited to the above-described 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-described embodiment, the height of the protrusion 200 is set so that the lower surface of the electrode 178 and the upper surface of the resin laminate 152 are parallel when the electronic component 172 is pressed against the resin laminate 152. On the other hand, if the pressing operation of the electronic component 172 is not performed, the height of the protrusion 200 may be set so that the lower surface of the electrode 178 and the upper surface of the resin laminate 152 are parallel when the electronic component 172 is attached onto the resin laminate 152.

[0055] Furthermore, in cases where the bump 168 is thin, the height dimension of the protrusion 200 may be set in accordance with the inclination angle α of the electrode, etc., without considering the height dimension of the bump 168. Furthermore, in cases where the bump 168 is hardly deformed by compression, the height dimension of the protrusion 200 may be set in accordance with the height dimension of the bump 168 before compression, etc. Furthermore, in cases where the protrusion 200 is hardly deformed by compression, the height dimension of the protrusion 200 may be set in accordance with the inclination angle α of the electrode, etc., without considering the amount of deformation of the protrusion 200 due to compression.

[0056] Furthermore, in the above embodiment, the height dimension of the protrusion 200 is set so that the lower surface of the electrode 178 is parallel to the upper surface of the resin laminate 152. On the other hand, the height dimension of the protrusion 200 may be set so that the inclination of the lower surface of the electrode 178 relative to the upper surface of the resin laminate 152 is reduced. Even if the lower surface of the electrode 178 is not parallel to the upper surface of the resin laminate 152, if the inclination of the lower surface of the electrode 178 relative to the upper surface of the resin laminate 152 is reduced, the contact area between the electrode 178 and the bump 168 increases, and therefore, electrical continuity between the electrode 178 and the bump 168 can be ensured.

[0057] In the above embodiment, the protrusion 200 is formed together with the resin laminate 157 after the wiring 162 is formed. However, the protrusion 200 may be formed on the resin laminate 152 before the wiring 162 is formed, as shown in FIG. 22 . In other words, the protrusion 200 may be formed together with the resin laminate 152.

[0058] 15, the protrusion 200 is formed in a strip shape along the extension direction of the side edge 202. Alternatively, as shown in FIG. 23, a plurality of protrusions 230 may be formed along the extension direction of the side edge 202.

[0059] Furthermore, in the above embodiment, the conductive paste 166 is used as the conductive 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.

[0060] In the above embodiment, an ultraviolet curable resin is used as the resin forming the resin laminates 152 and 157, and an ultraviolet curable resin is also used as the resin forming the protrusion 200. In other words, the resin forming the resin laminates 152 and 157 and the resin forming the protrusion 200 are the same curable resin. However, the resin forming the resin laminates 152 and 157 and the resin forming the protrusion 200 may be different curable resins.

[0061] Furthermore, in the above embodiment, the wiring 162 and the electrode 178 are connected by the bump 168, but various other means than the bump 168 can be used as long as they electrically connect the wiring 162 and the electrode 178.

[0062] In addition, in the above embodiment, the electronic component 172 is pressed against the resin laminate 152, but the resin laminate 152 may be pressed against the electronic component 172, or the resin laminate 152 and the electronic component 172 may be pressed against each other. In other words, it is sufficient that the electronic component 172 is pressed relatively against the resin laminate 152.

[0063] In addition, in the above embodiment, ultraviolet curable resin is used as the resin forming the resin laminates 152, 157 and the resin forming the protrusion portion 200, but it is also possible to form thermosetting resin, two-component mixed curable resin, thermoplastic resin, etc.

[0064] Furthermore, in the above embodiment, the conductive paste is dispensed by the dispenser 106, but it may be transferred by a transfer device or the like. Also, the conductive paste may be printed by screen printing.

[0065] This specification also discloses the technical idea of ​​changing "the circuit formation method according to claim 1" in claim 3 originally filed to "the circuit formation method according to claim 1 or claim 2."

[0066] 10: Circuit forming apparatus (circuit forming apparatus) 28: Control device 76: Inkjet head (metal-containing liquid ejection device) 88: Inkjet head (resin ejection device) 132: Mounting portion (mounting device) 152: Resin laminate (resin layer) 160: Metal ink (metal-containing liquid) 162: Wiring (metal wiring) 166: Conductive paste (conductive fluid) 168: Bump 172: Electronic component 176: Component body 178: Electrode 200: Protrusion 220: Wiring forming portion (wiring forming process) (wiring forming treatment) 222: Protrusion forming portion (protrusion forming process) (protrusion forming treatment) 224: Bump forming portion (bump forming process) 226: Mounting portion (mounting process) (mounting treatment) 228: Pressing portion (pressing process)

Claims

1. A circuit forming method comprising: a wiring forming step of forming wiring on the upper surface of a resin layer using a metal-containing liquid; a protrusion forming step of forming protrusions using a curable resin at planned positions for mounting the component body of an electronic component on the upper surface of the resin layer; and a mounting step of mounting the electronic component on the upper surface of the resin layer so that electrodes arranged at an angle on the underside of the component body come into contact with the wiring and the component body comes into contact with the protrusions, wherein the protrusion forming step forms the protrusions at a height that tilts the underside of the component body so that the inclination of the underside of the electrode relative to the upper surface of the resin layer is reduced when the electronic component is mounted on the upper surface of the resin layer in the mounting step.

2. A circuit forming method as described in claim 1, wherein the protrusion forming process forms the protrusion to a height that tilts the lower surface of the component body so that the lower surface of the electrode and the upper surface of the resin layer are parallel when the electronic component is mounted on the upper surface of the resin layer in the mounting process.

3. A circuit forming method as claimed in claim 1, wherein the electrode is disposed on one of a pair of opposing side edges on the underside of the component body, and the protrusion forming step forms the protrusion at a predetermined position on the other of the pair of side edges of the component body.

4. A circuit forming method according to claim 3, wherein the protrusion forming step forms the protrusion along the direction in which the other of the pair of side edges of the component body extends.

5. A circuit forming method according to any one of claims 1 to 4, wherein the protrusion forming step forms the protrusion with a height corresponding to the inclination angle of the electrode relative to the underside of the component body.

6. The circuit forming method according to claim 5, further comprising a connection forming step of forming a connection using a conductive fluid at a position where the electrode is to be attached to the wiring, and wherein the protrusion forming step forms the protrusion having a height corresponding to the inclination angle of the electrode and the height dimension of the connection.

7. The circuit formation method according to claim 6, further comprising a pressing step of pressing the electronic component relatively against the resin layer after the electronic component has been mounted on the upper surface of the resin layer in the mounting step, and wherein the protrusion formation step forms the protrusion having a height corresponding to the inclination angle of the electrode and the height dimension of the connection portion after being pressed in the pressing step.

8. A circuit forming device comprising: a metal-containing liquid discharging device that discharges a metal-containing liquid; a resin discharging device that discharges a curable resin; a mounting device that performs mounting work of electronic components; and a control device, wherein the control device performs the following: a wiring forming process that forms wiring by discharging the metal-containing liquid onto the upper surface of a resin layer by the metal-containing liquid discharging device; a protrusion forming process that forms protrusions by discharging the curable resin by the resin discharging device at planned mounting positions of the component bodies of the electronic components on the upper surface of the resin layer; and a mounting process that mounts the electronic components on the upper surface of the resin layer by the mounting device so that electrodes arranged at an angle on the lower surface of the component bodies come into contact with the wiring and the component bodies come into contact with the protrusions, wherein the protrusion forming process forms the protrusions at a height that tilts the lower surface of the component bodies so that the inclination of the lower surfaces of the electrodes relative to the upper surface of the resin layer is reduced when the electronic component is mounted on the upper surface of the resin layer in the mounting process.

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