JP7624059B2 - Electronic component mounting method and electronic component mounting device - Google Patents

Description

The present invention relates to a method for mounting electronic components, in which a conductive fluid is applied to metal wiring arranged on a resin layer and an electronic component is mounted by bringing an electrode into contact with the conductive fluid.

The following patent document describes a technique for mounting electronic components so that they are electrically connected to metal wiring.

JP 2008-135410 A

The objective of this specification is to properly mount electronic components so that they are electrically connected to metal wiring.

In order to solve the above problem, the present specification provides a method for manufacturing a semiconductor device, comprising the steps of: applying a conductive fluid to a position on a metal wiring arranged on a resin layer where an electrode of a first electronic component is to be mounted; a first curing step of curing the applied conductive fluid; applying a conductive fluid to a position on the resin layer where a component body of the first electronic component is to be mounted, and applying a conductive fluid to a position on the metal wiring arranged on the resin layer where an electrode of a second electronic component is to be mounted; bringing the electrode of the first electronic component into contact with the conductive fluid cured in the first curing step; and curing the first electronic component. Disclosed is a method for mounting electronic components, the method including: a step of placing a first electronic component by contacting the component body of a child component with a conductive fluid applied to a planned mounting position of the component body of the child component; a step of placing the second electronic component by contacting an electrode of the second electronic component with a conductive fluid applied to a planned mounting position of an electrode of the second electronic component; and a second curing step of curing the conductive fluid applied to the planned mounting position of the component body of the first electronic component and to the planned mounting position of the electrode of the second electronic component after the first electronic component and the second electronic component have been mounted.

The present specification also provides a method for manufacturing a semiconductor device, comprising: an application device for applying a conductive fluid; a curing device for curing the conductive fluid applied by the application device; a mounting device for mounting an electronic component; and a control device, the control device performing a process of applying the conductive fluid to a position on a metal wiring arranged on a resin layer where an electrode of a first electronic component is to be mounted; a first curing process of curing the applied conductive fluid; applying the conductive fluid to a position on the resin layer where a component body of the first electronic component is to be mounted, and applying the conductive fluid to a position on the metal wiring arranged on the resin layer where an electrode of a second electronic component is to be mounted; and curing the conductive fluid cured in the first curing process. The present invention discloses an electronic component mounting device that performs the steps of: placing the first electronic component by contacting the electrodes of the first electronic component with a conductive fluid and contacting the component body of the first electronic component with a conductive fluid applied to the intended mounting positions of the component body of the first electronic component; placing the second electronic component by contacting the electrodes of the second electronic component with the conductive fluid applied to the intended mounting positions of the electrodes of the second electronic component; and after the first electronic component and the second electronic component have been mounted, hardening the conductive fluid applied to the intended mounting positions of the component body of the first electronic component and the intended mounting positions of the electrodes of the second electronic component.

In the present disclosure, the first electronic component is mounted by contacting the electrodes with the cured conductive fluid and the component body with the uncured conductive fluid. Meanwhile, the second electronic component is mounted by contacting the electrodes with the uncured conductive fluid. In this way, the first electronic component and the second electronic component are mounted using different techniques, which improves throughput and allows the electronic components to be properly mounted on the metal wiring.

FIG. 1 is a diagram showing a circuit forming device. FIG. 2 is a block diagram showing a control device. 1 is a cross-sectional view showing a heat-sensitive release film attached onto a base. FIG. 2 is a cross-sectional view showing a circuit board with a resin laminate formed thereon. FIG. 2 is a cross-sectional view showing a circuit board having wiring formed on a resin laminate. FIG. 2 is a cross-sectional view showing a circuit board in a state in which a resin laminate is further formed on the resin laminate. 1 is a cross-sectional view showing a circuit board in a state in which a conductive paste is applied onto wiring. FIG. 2 is a cross-sectional view showing a circuit board on which two electronic components are mounted. 4 is a cross-sectional view showing a circuit board in a state in which a conductive paste is applied onto wiring and a resin laminate. FIG. FIG. 2 is a cross-sectional view showing a circuit board on which two electronic components are mounted. 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. 4 is a cross-sectional view showing a circuit board with an electronic component pressed against a resin laminate. FIG. FIG. 2 is a cross-sectional view showing a circuit board with small electronic components mounted thereon. FIG. 2 is a cross-sectional view showing a circuit board with small electronic components mounted thereon. FIG. 2 is a cross-sectional view showing a circuit board on which two electronic components are mounted. 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. 4 is a cross-sectional view showing a circuit board with an electronic component pressed against a resin laminate. FIG. 1 is a cross-sectional view showing a circuit board in a state in which a conductive paste has been applied to positions where electrodes of a large electronic component are to be attached. 1 is a cross-sectional view showing a circuit board in a state in which a conductive paste has been applied to the component bodies of larger electronic components and to positions where electrodes of smaller electronic components are to be mounted. FIG.

1 shows the circuit forming device 10. The circuit forming device 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 arranged on a base 29 of the circuit forming device 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.

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, and the X-axis slider 36 is moved to any position in the X-axis direction by the drive of the electromagnetic motor 38. 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. The 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 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.

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.

The first modeling unit 22 is a unit that models the wiring of the circuit board, and has a first printing section 72 and a baking section 74. The first printing section 72 has an inkjet head (see Figure 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 also ejects the metal ink from multiple nozzles, for example, by a piezoelectric method using piezoelectric elements.

The baking section 74 has an infrared irradiation device 78 (see Figure 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 the application of energy causes the evaporation of the solvent and the decomposition of the protective film for the metal particles, i.e., the dispersant, and the like, and the metal particles come into contact or fuse together, thereby increasing the conductivity. Then, as the metal ink is baked, metal wiring is formed.

The second modeling unit 23 is a unit that models the resin layer of the 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 hardens when exposed to ultraviolet light. The inkjet head 88 may be, for example, a piezo type that uses a piezoelectric element, or a thermal type that heats the resin to generate bubbles and ejects the resin from multiple nozzles.

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 top surface of the UV-curable resin discharged by the inkjet head 88, for example by leveling the surface of the UV-curable resin while scraping off excess resin with a roller or blade, thereby making the thickness of the UV-curable resin uniform. The irradiation device 92 has a mercury lamp or LED as a light source, and irradiates the discharged UV-curable resin with ultraviolet light. This hardens the discharged UV-curable resin, forming a resin layer.

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

The conductive paste dispensed by the dispenser 106 is then heated by the heater 66 built into the base 60, and the resin in the heated conductive paste hardens. At this time, the resin in the conductive paste hardens and shrinks, and the flake-shaped metal particles dispersed in the resin 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 exerts its adhesive power by hardening when heated.

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 116 (see FIG. 2) that dispenses thermosetting resin. Thermosetting resin is a 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.

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. 12) 122, a rubber sheet (see FIG. 12) 124, and a cylinder (see FIG. 2). 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.

The mounting unit 27 is a unit that mounts electronic components on a circuit board, and has a supply section 130 and a mounting section 132. The 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. The supply section 130 is not limited to the tape feeder 134, and may be a tray-type supply device that picks up and supplies electronic components from a tray. The supply section 130 may be configured to include both a tape-type and a tray-type supply device, or other types of supply devices.

The mounting section 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 electronic components. The suction nozzle suctions and holds electronic components by sucking air when negative pressure is supplied from a positive and negative pressure supply device (not shown). Then, the positive and negative pressure supply device supplies a slight positive pressure to the suction nozzle, which releases the electronic components. The moving device 138 moves the mounting head 136 between the supply position of electronic components by the tape feeder 134 and the board placed on the base 60. As a result, in the mounting section 132, the 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 on the board.

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, ROM, RAM, etc., and is mainly a computer, and is connected to the plurality of drive circuits 142. As a result, the operation 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 is controlled by the controller 140.

In the circuit forming device 10, a resin laminate is formed on the base 60 using 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 paste, and the electronic components are fixed with resin to form a circuit board.

Specifically, as shown in FIG. 3, a heat-sensitive peeling film 150 is first laid on the upper surface of the base 60 of the stage 52. The heat-sensitive peeling film 150 has adhesiveness, so it adheres appropriately to the upper surface of the base 60. Then, a circuit board is formed on the heat-sensitive peeling film 150, and the heat-sensitive peeling film 150 adheres closely to the base 60, preventing the circuit board from shifting during circuit formation. Note that the adhesiveness of the heat-sensitive peeling film 150 decreases when heated, so that after the circuit board is formed on the heat-sensitive peeling film 150, the heat-sensitive peeling film 150 can be easily peeled off from the base 60 together with the circuit board formed on the heat-sensitive peeling film 150 by heating the heat-sensitive peeling film 150.

Once the heat-sensitive peel-off film 150 is laid on the base 60, the stage 52 is moved below the second modeling unit 23. Then, in the second modeling unit 23, a resin laminate 152 is formed on the heat-sensitive peel-off film 150, as shown in Figure 4. The resin laminate 152 is formed by repeatedly ejecting ultraviolet curing resin from the inkjet head 88 and irradiating the ejected ultraviolet curing resin with ultraviolet light by the irradiation device 92.

In more detail, in the second printing section 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 heat-sensitive peelable film 150. Next, once the ultraviolet curable resin has been ejected in a thin film, the ultraviolet curable resin is flattened by the flattening device 90 in the curing section 86 so that the film thickness of the ultraviolet curable resin is uniform. Then, the irradiation device 92 irradiates the thin film of ultraviolet curable resin with ultraviolet light. This forms a thin film resin layer 153 on the heat-sensitive peelable film 150.

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 the flattening device 90, and the irradiation device 92 irradiates the ejected thin film of ultraviolet curable resin with ultraviolet light, thereby laminating a thin film of resin layer 153 on top of the thin film of resin layer 153. In this manner, ejection of ultraviolet curable resin onto the thin film of resin layer 153 and irradiation with ultraviolet light are repeated, and a plurality of resin layers 153 are laminated to form a resin laminate 152.

Next, when the resin laminate 152 is formed, 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 upper surface of the resin laminate 152, 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 on the upper surface of the resin laminate 152. In FIG. 5, three wirings 162 are formed, but 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.

Next, when the wiring 162 is 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 curing resin in a thin film so that the ends of the three wirings 162 are exposed. Next, 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 is uniform. Then, the irradiation device 92 irradiates the thin film of ultraviolet curing resin with ultraviolet light. As a result, a resin layer 156 is formed on the resin laminate 152, as shown in FIG. 6.

Next, the inkjet head 88 ejects the ultraviolet curing resin in a thin film only on the resin layer 156. That is, the inkjet head 88 ejects the ultraviolet curing resin in a thin film on the resin layer 156 so that the ends of the three wirings 162 are exposed. Then, the thin film of ultraviolet curing resin is flattened by the flattening device 90, and the irradiation device 92 irradiates the ultraviolet curing resin ejected in a thin film with ultraviolet light, so that the resin layer 156 is laminated on the resin layer 156. In this way, the ejection of the ultraviolet curing resin on the resin layer 156 and the irradiation of ultraviolet light are repeated, and a plurality of resin layers 156 are laminated to form the resin laminate 157. As a result, the resin laminate 157 is formed on the resin laminate 152, and the step between the resin laminate 152 and the resin laminate 157 functions as the cavity 154.

In this manner, when the resin laminate 157 is formed on the resin laminate 152, the stage 52 is moved below the third modeling unit 24. Then, in the third printing section 100 of the third modeling unit 24, the dispenser 106 dispenses conductive paste 166 onto both ends of the wiring 162b and onto the ends of the wiring 162a and wiring 162c that face both ends of the wiring 162b, as shown in FIG.

In this way, when the conductive paste 166 is discharged onto the end of the wiring 162, in the conventional method, the electronic component is placed on the resin laminate 152 so that the electrode contacts the conductive paste 166, and after the electronic component is placed, the conductive paste 166 is heated and hardened. Specifically, when the conductive paste 166 is discharged onto the end of the wiring 162, the stage 52 is moved below the mounting unit 27. Then, in the mounting unit 27, the electronic component (see FIG. 8) 172 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 arranged on the lower surface of the component body 176. Then, the mounting head 136 is moved by the moving device 138, and the electronic component 172 held by the suction nozzle is placed on the upper surface of the resin laminate 152 as shown in FIG. In FIG. 8, two electronic components 172 are placed on the upper surface of the resin laminate 152, and the two electronic components 172 are different in size. Therefore, the smaller electronic component is referred to as electronic component 172a, and the larger electronic component is referred to as electronic component 172b. Then, electronic component 172a is placed so that two electrodes 178 of electronic component 172a contact the conductive paste 166 discharged onto the ends of the two wirings 162a and 162b. Also, electronic component 172b is placed so that two electrodes 178 of electronic component 172b contact the conductive paste 166 discharged onto the ends of the two wirings 162b and 162c. Then, when the two electronic components 172a and 172b are placed on the upper surface of the resin laminate 152, the resin laminate 152 is heated to 105 degrees for one hour by a heater 66 built into the base 60. As a result, the conductive paste 166 is heated through the resin laminate 152 and hardened, thereby exhibiting conductivity, and the electronic components 172 are electrically connected to the wiring.

In this way, in the conventional method, after the conductive paste 166 was discharged onto the wiring 162, the electronic component 172 was attached before the conductive paste 166 was cured. In other words, the electronic component 172 was attached so that the electrode 178 was in contact with the conductive paste 166 in an uncured state. The conductive paste 166 in contact with the electrode 178 was then heated and cured. However, the conductivity of the conductive paste decreases when it is deformed or stress is applied during thermal curing. For this reason, when a circuit board is formed using the conventional method, the conductivity between the wiring 162 and the electrode 178 of the electronic component 172 cannot be adequately ensured.

In consideration of this, in the circuit forming device 10, as shown in Fig. 7, when the conductive paste 166 is discharged onto the end of the wiring 162, the conductive paste 166 is heated and hardened before the electronic component 172 is attached. In other words, the conductive paste 166 is heated and hardened by the heater 66 without being deformed or subjected to stress. This makes it possible to prevent a decrease in conductivity when the conductive paste 166 hardens.

Then, when the conductive paste 166 hardens, in the third printing unit 100, the dispenser 106 dispenses conductive paste 170 onto the bottom surface of the cavity 154 between the wiring 162a and the wiring 162b, that is, onto the upper surface of the resin laminate 152, and onto the upper surface of the resin laminate 152 between the wiring 162b and the wiring 162c, as shown in FIG. 9. Then, when the conductive paste 170 is dispensed onto the upper surface of the resin laminate 152, the stage 52 is moved below the mounting unit 27 while the conductive paste 170 is not heated and is in an unhardened state. In other words, the conductive paste 166 dispensed onto the wiring 162 is heated and hardened, but the conductive paste 170 dispensed onto the resin laminate 152 is not heated and is in an unhardened state while the stage 52 is moved below the mounting unit 27.

Then, in the mounting unit 27, the electronic components 172a and 172b are supplied by the tape feeder 134, and the mounting head 136 and the moving device 138 are operated to place the electronic components 172a and 172b on the bottom surface of the cavity 154, that is, on the upper surface of the resin laminate 152. Specifically, as shown in FIG. 10, the electronic component 172a is placed so that the electrode 178 contacts the conductive paste 166 in a cured state on the wiring 162a and 162b. At this time, the component body 176 of the electronic component 172a contacts the conductive paste 170 in an uncured state discharged between the wiring 162a and 162b. Also, the electronic component 172b is placed so that the electrode 178 contacts the conductive paste 166 in a cured state on the wiring 162b and 162c. At this time, the component body 176 of the electronic component 172b contacts the conductive paste 170 in an uncured state discharged between the wiring 162b and 162c. That is, conductive paste 166 is dispensed onto the intended position of electrode 178 on wiring 162, and conductive paste 170 is dispensed onto the intended position of component body 176. Therefore, by placing electronic component 172 on resin laminate 152, electrode 178 comes into contact with conductive paste 166 in a cured state on wiring 162, and component body 176 comes into contact with conductive paste 170 in an uncured state.

In this way, by placing 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 paste 166 in a hardened state, the contact area between the electrode 178 and the conductive paste 166 is small at this point. On the other hand, since the component body 176 of the electronic component 172 contacts the conductive paste 170 in an unhardened state, the contact area between the component body 176 and the conductive paste 170 becomes somewhat large. Therefore, the electronic component 172 is fixed to the upper surface of the resin laminate 152 in the component body 176 by the adhesive force of the conductive 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 paste 170 is heated through the resin laminate 152 and hardened.

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. 11. 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 into 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.

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, as shown in FIG. 12, 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. 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.

When the electronic components are compressed in the compression unit 26, the resin laminate 152 is heated at 85 degrees for 45 minutes by the heater 66 built into the base 60. As a result, the thermosetting resin 180 is heated and hardened through the resin laminate 152. 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. As the electronic components 172 are compressed, that is, the electronic components 172 mounted on the resin laminate 152 are pressed against the resin laminate 152, the conductive paste 166 in contact with the electrodes 178 of the electronic components 172 is deformed, and the contact area between the electrodes 178 and the conductive paste 166 is increased. In particular, the Young's modulus of the conductive paste 166 is low in the 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 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 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 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 paste 170 also increases. In this way, the contact area between the component body 176 and the conductive paste 170 is increased, and the adhesive strength of the conductive paste 170 allows the electronic component 172 to be suitably fixed to the resin laminate 152 .

In this way, the electronic components 172 placed on the upper surface of the resin laminate 152 are electrically connected to the wiring by the conductive paste 166 and are fixed by the adhesive force of the conductive paste 170, so that the circuit board is formed on the heat-sensitive release film 150 on the upper surface of the base 60. Then, in order to peel the heat-sensitive release film 150 from the formed circuit board, the heat-sensitive release film 150 is heated to 130 degrees for one hour by the heater 66 built into 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, completing the formation of the circuit board.

By forming a circuit board using this method, it is possible to appropriately ensure the conductivity between the wiring 162 and the electrode 178 of the electronic component 172, compared to a circuit board formed using a conventional method. In more detail, in the conventional method, the conductive paste 166 is discharged onto the wiring 162, the electronic component 172 is mounted so that the conductive paste 166 contacts the electrode 178, and then the conductive paste 166 is heated and cured. In other words, in the conventional method, after the electronic component 172 is mounted, the electronic component is mounted using a process of heating and curing the conductive paste 166 (hereinafter referred to as the "post-curing process").

On the other hand, in the new method, when the conductive paste 166 is discharged onto the wiring 162, the conductive paste 166 is heated and hardened before the electronic component 172 is mounted. In other words, in the new method, the electronic component is mounted using a process of heating and hardening the conductive paste 166 before the electronic component 172 is mounted (hereinafter referred to as the "pre-hardening process"). In this way, by using the pre-hardening process, it is possible to heat and harden the conductive paste 166 without deforming the conductive paste 166 and without applying stress to the conductive paste 166, and it is possible to prevent a decrease in conductivity when the conductive paste 166 hardens. In addition, when the pre-hardening process is used, the conductive paste 170 is applied to the intended mounting position of the component body 176 before the electronic component 172 is mounted, and the conductive paste 170 is not heated. In other words, the conductive paste 166 applied to the intended mounting position of the electrode 178 is heated before the electronic component 172 is mounted, but the conductive paste 170 applied to the intended mounting position of the component body 176 is not heated. Therefore, when electronic component 172 is mounted, component body 176 comes into contact with uncured conductive paste 170, increasing the contact area between component body 176 and conductive paste 170 to a certain extent. This allows electronic component 172 to be fixed to resin laminate 152 by the adhesive force of conductive paste 170.

In this way, by mounting the electronic component using the pre-curing process, the conductivity between the wiring 162 and the electrode 178 of the electronic component 172 is appropriately ensured, and the adhesive force of the conductive paste 170 makes it possible to prevent the mounted electronic component from being displaced. However, when the pre-curing process is used, the number of times the conductive paste is discharged increases compared to when the post-curing process is used, and the discharge time of the conductive paste is longer. In detail, in the pre-curing process, the conductive paste 166 is applied to the intended mounting positions of the two electrodes 178 of the electronic component 172, and the conductive paste 170 is applied to the intended mounting position of the component body 176 of the electronic component 172. In other words, in the pre-curing process, the conductive paste 166 is applied to two locations and the conductive paste 170 is applied to one location, so that the conductive paste is applied to a total of three locations. On the other hand, in the post-curing process, the conductive paste 166 is applied only to the intended mounting positions of the two electrodes 178 of the electronic component 172, so that the conductive paste is applied to two locations. In this way, the number of locations where the conductive paste is dispensed in the pre-curing process is 1.5 times that of the conductive paste dispensed in the post-curing process, so the dispensing time of the conductive paste in the pre-curing process is longer than the dispensing time of the conductive paste in the post-curing process.

In view of this, in the circuit forming device 10, the post-curing process and the pre-curing process are selectively performed according to the size of the electronic components. In detail, when the conductive paste is deformed or stressed during thermal curing, the conductivity decreases. In addition, the electronic components expand during thermal curing, but the amount of thermal expansion when a small electronic component is heated is less than the amount of thermal expansion when a large electronic component is heated. Therefore, even if the conductive paste is heated with a small electronic component mounted, the stress on the conductive paste is smaller than when the conductive paste is heated with a large electronic component mounted. In other words, when the conductive paste is heated with a small electronic component mounted, the conductive paste does not deform much and only a small stress is applied, so the conductivity is hardly reduced. Therefore, in the circuit forming device 10, the post-curing process is used when mounting small electronic components that are equal to or smaller than a preset size (hereinafter referred to as the "set size"), and the pre-curing process is used when mounting electronic components that are larger than the set size.

The part size with a maximum length of one side of 1.6 mm is set as the set size. Specifically, for example, the part sizes include "3216", "2012", "1608", "1005", "0603", etc., but the part sizes below the set size are "1608", "1005", "0603", and the part sizes above the set size are "3216" and "2012". Therefore, the pre-curing process is used when mounting electronic parts with part sizes "1608", "1005", and "0603", and the post-curing process is used when mounting electronic parts with part sizes "3216" and "2012". Note that the part size of electronic part 172a is below the set size, and the part size of electronic part 172b is larger than the set size. Therefore, electronic part 172a below the set size is mounted using the post-curing process, and electronic part 172b above the set size is mounted using the pre-curing process.

In more detail, when the conductive paste 166 is discharged onto the end of the wiring 162 as shown in FIG. 7, the mounting unit 27 places an electronic component 172a of a set size or smaller on the resin laminate 152 as shown in FIG. 13. At this time, the electronic component 172a is placed on the resin laminate 152 so that the uncured conductive paste 166 discharged onto the wiring 162a and wiring 162b comes into contact with the two electrodes. Then, when the electronic component 172a of a set size or smaller is placed on the resin laminate 152, the conductive paste 166 is heated by the heater 66 and hardened. Note that the heating by the heater 66 hardens not only the conductive paste 166 in contact with the electrode 178 of the electronic component 172a, but also the remaining conductive paste 166, that is, the conductive paste 166 discharged onto the intended mounting position of the electrode 178 of the electronic component 172b.

In this way, when the conductive paste 166 discharged to the end of the wiring 162 hardens, in the third modeling unit 24, as shown in FIG. 14, the conductive paste 170 is discharged between the wiring 162b and the wiring 162c, that is, at the intended mounting position of the component body 176 of the electronic component 172b. Then, in the mounting unit 27, as shown in FIG. 15, an electronic component 172b larger than the set size is placed on the resin laminate 152. At this time, the conductive paste 166 hardened on the wiring 162b and the wiring 162c comes into contact with the electrode 178, and the electronic component 172b is placed on the resin laminate 152 so that the component body 176 comes into contact with the unhardened conductive paste 170 discharged on the resin laminate 152. Then, when the electronic component 172b larger than the set size is placed on the resin laminate 152, the conductive paste 170 is heated by the heater 66 and hardened.

Next, in the fourth modeling unit 25, as shown in Fig. 16, thermosetting resin 180 is injected between the electronic component 172 and the resin laminate 152, and the thermosetting resin 180 is semi-cured by being heated by the heater 66. Next, in the compression unit 26, as shown in Fig. 17, 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, and the thermosetting resin 180 is cured by being heated by the heater 66. This forms a circuit.

In this way, by mounting electronic components 172a that are equal to or smaller than the set size using a post-curing process and mounting electronic components 172b that are larger than the set size using a pre-curing process, it is possible to reduce the number of locations where the conductive paste is dispensed, and the time required to dispense the conductive paste can be shortened. However, even if the time required to dispense the conductive paste can be shortened, there is a risk that the time required to form the circuit cannot be shortened.

In detail, when only the pre-curing process is performed regardless of the component size, seven steps are performed from the discharge of the conductive paste 166 onto the wiring 162 to the curing of the thermosetting resin while compressing the electronic component 172. That is, seven steps are performed: the discharge step of the conductive paste 166 onto the wiring 162 (FIG. 7), the curing step of the conductive paste 166 (FIG. 7), the discharge step of the conductive paste 170 (FIG. 9), the step of placing two electronic components (FIG. 10), the curing step of the conductive paste 170 (FIG. 10), the step of injecting the thermosetting resin (FIG. 11), and the step of curing the thermosetting resin while compressing the electronic component (FIG. 12). On the other hand, when the pre-curing process and the post-curing process are selectively performed according to the component size, eight steps are performed from the discharge of the conductive paste 166 onto the wiring 162 to the curing of the thermosetting resin while compressing the electronic component 172. That is, eight steps are performed: a step of discharging conductive paste 166 onto wiring 162 (FIG. 7), a step of hardening conductive paste 166 (FIG. 7), a step of placing small electronic components 172a (FIG. 13), a step of discharging conductive paste 170 (FIG. 14), a step of placing large electronic components 172b (FIG. 15), a step of hardening conductive paste 170 (FIG. 15), a step of injecting thermosetting resin (FIG. 16), and a step of hardening thermosetting resin while compressing electronic components (FIG. 17). In this way, the number of steps when the pre-curing process and the post-curing process are selectively performed is one more than the number of steps when only the pre-curing process is performed, so that even if the time required for discharging the conductive paste can be shortened, the time required for forming the circuit cannot be shortened.

In view of this, the discharge of conductive paste 166 onto the intended mounting position of the electrode of small electronic component 172a and the discharge of conductive paste 170 onto the intended mounting position of the component body of large electronic component 172b are performed at the same timing, that is, in one process, thereby shortening the circuit formation time. Specifically, when the conductive paste 166 is discharged onto the end of wiring 162, as shown in FIG. 7, the conductive paste 166 is discharged onto both the intended mounting position of electrode 178 of small electronic component 172a and the intended mounting position of electrode 178 of large electronic component 172b in the above description. On the other hand, in order to shorten the circuit formation time, as shown in FIG. 18, the conductive paste 166 is discharged only onto the intended mounting position of electrode 178 of large electronic component 172b, and the conductive paste 166 is not discharged onto the intended mounting position of electrode 178 of small electronic component 172a. Then, when the conductive paste 166 is dispensed only onto the positions where the electrodes 178 of the large electronic component 172b are to be attached, the conductive paste 166 is heated by the heater 66 and hardened.

Next, as shown in FIG. 19, conductive paste 170 is discharged to the intended mounting position of component body 176 of large electronic component 172b, and conductive paste 166 is also discharged to the intended mounting position of electrode 178 of small electronic component 172a. At this point, with respect to the conductive paste discharged to the intended mounting position of large electronic component 172b, conductive paste 166 discharged to the intended mounting position of electrode 178 has hardened, and conductive paste 170 discharged to the intended mounting position of component body 176 is unhardened. On the other hand, with respect to the conductive paste discharged to the intended mounting position of small electronic component 172a, conductive paste 166 discharged to the intended mounting position of electrode 178 is unhardened. Then, large electronic component 172b is placed on resin laminate 152 so that electrode 178 contacts hardened conductive paste 166 and component body 176 contacts unhardened conductive paste 170, as shown in FIG. 15. Furthermore, the small electronic component 172a is placed on the resin laminate 152 so that the electrode 178 is in contact with the uncured conductive paste 166. Then, the uncured conductive paste 166 in contact with the electrode 178 of the small electronic component 172a and the uncured conductive paste 170 in contact with the component body 176 of the large electronic component 172b are heated by the heater 66 and cured.

16, thermosetting resin 180 is injected between electronic component 172 and resin laminate 152, and is heated by heater 66, causing the thermosetting resin 180 to semi-cure. Then, as shown in Fig. 17, electronic component 172 attached to resin laminate 152 is compressed from above to below by compression plate 122 via rubber sheet 124, and is heated by heater 66, causing the thermosetting resin 180 to harden. This forms a circuit.

When the conductive paste is discharged and hardened, and the electronic components are placed in this order, seven steps are performed from the discharge of the conductive paste 166 onto the wiring 162 to the hardening of the thermosetting resin while compressing the electronic components 172. That is, seven steps are performed: the discharge step of the conductive paste 166 onto the intended mounting position of the electrode of the large electronic component 172b (FIG. 18), the hardening step of the conductive paste 166 (FIG. 18), the discharge step of the conductive paste onto the intended mounting position of the component body of the large electronic component 172b and the intended mounting position of the electrode of the small electronic component 172a (FIG. 19), the mounting step of the two electronic components (FIG. 15), the hardening step of the conductive paste (FIG. 15), the injection step of the thermosetting resin (FIG. 16), and the hardening step of the thermosetting resin while compressing the electronic components (FIG. 17). In this way, by discharging and curing the conductive paste, placing electronic components, etc., it is possible to make the number of steps when the pre-curing process and the post-curing process are selectively performed the same as the number of steps when only the pre-curing process is performed. This makes it possible to shorten the time required to discharge the conductive paste by reducing the number of places where the conductive paste is discharged, and therefore to shorten the time required to form the circuit.

As shown in FIG. 2, the controller 140 of the control device 28 has a first application section 210, a first curing section 212, a second application section 214, a first placement section 216, a second placement section 218, a second curing section 220, an injection section 222, and a compression curing section 224. The first application section 210 is a functional section for discharging the conductive paste 166 to the intended mounting position of the electrode of the large electronic component 172b. The first curing section 212 is a functional section for curing the conductive paste 166 discharged to the intended mounting position of the electrode of the large electronic component 172b. The second application section 214 is a functional section for discharging the conductive paste to the intended mounting position of the component body of the large electronic component 172b and the intended mounting position of the electrode of the small electronic component 172a. The first placement section 216 is a functional section for placing the large electronic component 172b on the resin laminate 152 so that the electrode 178 contacts the cured conductive paste 166 and the component body 176 contacts the uncured conductive paste 170. The second placement section 218 is a functional section for placing the small electronic component 172a on the resin laminate 152 so that the electrode 178 contacts the uncured conductive paste 166. The second curing section 220 is a functional section for curing the conductive pastes 166 and 170 discharged to the component body of the large electronic component 172b and the electrode of the small electronic component 172a at the intended mounting position. The injection section 222 is a functional section for injecting a thermosetting resin between the electronic component 172 and the resin laminate 152. The compression curing section 224 is a functional section for curing the thermosetting resin while compressing the electronic components.

In the above embodiment, the circuit forming apparatus 10 is an example of an electronic component mounting apparatus. The control device 28 is an example of a control device. The heater 66 is an example of a curing device. The dispenser 106 is an example of a coating device. The mounting head 136 is an example of a mounting device. The resin laminate 152 is an example of a resin layer. The wiring 162 is an example of metal wiring. The conductive pastes 166 and 170 are an example of a conductive fluid. The electronic component 172a is an example of a second electronic component. The electronic component 172b is an example of a first 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 present invention is not limited to the above embodiment, and can be implemented 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 pre-curing process and the post-curing process are selectively performed according to the part size, but the pre-curing process and the post-curing process may be selectively performed according to the characteristics of the part. For example, the expansion coefficient of the material constituting the part may be used as the characteristic of the part, and the post-curing process may be used when the expansion coefficient is equal to or less than a predetermined value, and the pre-curing process may be used when the expansion coefficient is greater than the predetermined value. Also, the number of terminals that the part has may be used as the characteristic of the part, and the post-curing process may be used when the number of terminals is equal to or less than a predetermined number, and the pre-curing process may be used when the number of terminals is greater than the predetermined number.

In addition, in the above embodiment, the part size is set to a maximum side length of 1.6 mm, but it is possible to set various numerical values as the set size, such as the total value of two or more sides of a part, the area of the top surface of a part, or the volume of a part, rather than the length of one side of the part.

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

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 electronic component 172. In other words, the resin forming the resin laminate 152 and the resin fixing the electronic component 172 are different curable resins, but the resin forming the resin laminate 152 and the resin fixing the electronic component 172 may be the same curable resin.

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. The conductive paste may also be printed by screen printing.

10: Circuit forming device (electronic component mounting device) 28: Control device 66: Heater (curing device) 106: Dispenser (coating device) 136: Mounting head (mounting device) 152: Resin laminate (resin layer) 162: Wiring (metal wiring) 166: Conductive paste (conductive fluid) 170: Conductive paste (conductive fluid) 172a: Electronic component (second electronic component) 172b: Electronic component (first electronic component) 176: Component body 178: Electrode 180: Thermosetting resin (curable resin)

Claims (5)

applying a conductive fluid to a metal wiring arranged on the resin layer at a position where an electrode of a first electronic component is to be attached;
a first curing step of curing the applied conductive fluid;
applying a conductive fluid to a position on the resin layer where a component body of the first electronic component is to be mounted, and applying a conductive fluid to a metal wiring arranged on the resin layer where an electrode of a second electronic component is to be mounted;
a step of placing the first electronic component by bringing electrodes of the first electronic component into contact with the conductive fluid hardened in the first hardening step and bringing a component body of the first electronic component into contact with the conductive fluid applied to a planned mounting position of the component body of the first electronic component;
placing the second electronic component by bringing the electrodes of the second electronic component into contact with a conductive fluid applied to a position where the electrodes of the second electronic component are to be mounted;
a second curing step of curing the conductive fluid applied to the intended mounting positions of a component body of the first electronic component and the intended mounting positions of an electrode of the second electronic component after the first electronic component and the second electronic component are placed;
An electronic component mounting method comprising: The first electronic component is a larger electronic component than the second electronic component.
2. The electronic component mounting method according to claim 1. The first electronic component is an electronic component having a size larger than a preset electronic component size, and the second electronic component is an electronic component having a size smaller than the preset electronic component size.
3. The electronic component mounting method according to claim 1 or 2. an injection step of injecting a curable resin between the first electronic component and the resin layer and between the second 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 first electronic component and the second electronic component against the resin layer after the curable resin is injected in the injection step;
The electronic component mounting method according to any one of claims 1 to 3, further comprising: An application device that applies a conductive fluid;
a curing device that cures the conductive fluid applied by the application device;
A placement device for placing electronic components;
A control device;
Equipped with
The control device includes:
applying a conductive fluid to a metal wiring arranged on the resin layer at a position where an electrode of a first electronic component is to be attached;
a first curing step of curing the applied conductive fluid;
applying a conductive fluid to a position on the resin layer where a component body of the first electronic component is to be mounted, and applying a conductive fluid to a metal wiring arranged on the resin layer where an electrode of a second electronic component is to be mounted;
a step of placing the first electronic component by bringing electrodes of the first electronic component into contact with the conductive fluid hardened in the first hardening step and bringing a component body of the first electronic component into contact with the conductive fluid applied to a planned mounting position of the component body of the first electronic component;
placing the second electronic component by bringing the electrodes of the second electronic component into contact with a conductive fluid applied to a position where the electrodes of the second electronic component are to be mounted;
a second curing step of curing the conductive fluid applied to the intended mounting positions of a component body of the first electronic component and the intended mounting positions of an electrode of the second electronic component after the first electronic component and the second electronic component are placed;
An electronic component placement machine that performs the above steps.

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