JP7316742B2 - Manufacturing method of mounting board by 3D additive manufacturing - Google Patents

Description

The present disclosure relates to a technology for manufacturing a mounting board in which electronic components are mounted on the board using three-dimensional additive manufacturing.

2. Description of the Related Art Conventionally, various techniques have been proposed for manufacturing a printed wiring board by laminating wiring and an insulating layer. In the manufacturing method of Patent Document 1 below, a plurality of mounting boards on which electronic components are mounted are manufactured on one worksheet (aggregate board), and the worksheet is diced to obtain individual mounting boards. doing In this manufacturing method, a plate-like frame member surrounding each mounting substrate is used in order to suppress the worksheet from warping due to the stress generated during the formation of the insulating layer.

JP 2009-32823 A (Paragraphs 0037, 0038, FIG. 8, FIG. 15)

Incidentally, in recent years, techniques have been developed for forming a mounting board on which electronic components are mounted using three-dimensional layered manufacturing. For example, a resin or metal curable viscous fluid is applied onto a substrate from an inkjet head, and the applied curable viscous fluid is cured to form a resin layer or wiring in a desired shape.

In manufacturing a mounting substrate by three-dimensional layered manufacturing, stress due to heating during curing accumulates in the substrate during the process of repeating coating and curing, and there is a risk that the substrate may warp. In particular, if the board warps at the part where the electronic component is mounted during or after the electronic component is mounted, there is a risk that a part of the connecting portion, such as a bump, that is connected to the component terminal of the electronic component may swell or crack. .

In the manufacturing method of Patent Literature 1 described above, a plate-shaped frame member surrounding the mounting board on which electronic components are mounted is prepared as a member separate from the mounting board. The plate-shaped frame member is arranged on a mounting substrate, ie, a non-product area (an area where electronic components are not mounted) surrounding the final product. Then, the plate-shaped frame member is separated from the mounting substrate by dicing. For this reason, depending on the mounting position of the electronic component and the size of the mounting board, the distance between the position where the component terminal of the electronic component is arranged and the plate-like frame member becomes long, and the warpage of the board occurring at the mounting position is sufficiently prevented. There is a risk that it will not be possible to control

The present disclosure has been made in view of such circumstances, and provides a method for manufacturing a mounting substrate by three-dimensional lamination molding that can effectively suppress the warpage of the substrate that occurs at the arrangement position where the component terminal of the electronic component is arranged. The task is to provide

In order to solve the above problems, the present disclosure provides a method for manufacturing a mounting board in which a plurality of wirings and a plurality of component terminals of an electronic component are connected by a plurality of connection portions by three-dimensional lamination molding, comprising: a first metal fluid application step of applying a first metal fluid in which metal particles are dispersed in a solvent ; and a wiring forming step of forming a plurality of wirings by curing the first metal fluid applied onto the substrate. a resin material applying step of applying a resin material to a position surrounding each of the plurality of component terminals of the electronic component and on each of the plurality of wirings; and each of the plurality of wirings. a reinforcing member forming step of curing the resin material applied to the above to form a reinforcing member surrounding the arrangement position; and a viscous fluid containing metal particles on each of the plurality of wirings corresponding to the arrangement position. a second metal fluid applying step of applying a second metal fluid, disposing the plurality of component terminals of the electronic component at the arrangement position, and disposing the plurality of components of the electronic component via the second metal fluid an electronic component arrangement step of connecting each of the terminals and a plurality of the wirings; and forming a plurality of the connection portions by heating and curing the second metal fluid applied onto each of the plurality of the wirings to form the electronic component. and a mounting step of mounting the .

According to the method of manufacturing a mounting board by three-dimensional lamination molding of the present disclosure, a reinforcing member is formed of a resin material at a position surrounding the component terminal (arrangement position) of the electronic component and on the wiring. Accordingly, by embedding at least part of the wiring and forming a reinforcing member surrounding the electronic component to increase the thickness of the substrate, the rigidity of the substrate at the arrangement position can be increased. Further, by forming the reinforcing member at the position where the wiring is partially buried, the reinforcing member and the component terminal can be brought close to each other, and the warp of the substrate occurring at the arrangement position can be effectively suppressed. It is possible to suppress swelling and cracking of the connection portion, and improve the yield of connection of electronic components.

It is a figure which shows a mounting board manufacturing apparatus. It is a block diagram which shows a control apparatus. It is a block diagram which shows a control apparatus. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a top view for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a top view for demonstrating the manufacturing process of a mounting board. FIG. 10 is a cross-sectional view showing a cross section taken along line II shown in FIG. 9; It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a top view for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a top view for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the manufacturing process of a mounting board. It is a schematic diagram for demonstrating the mounting board using the reinforcing member of another example. It is a schematic diagram for demonstrating the mounting board using the reinforcing member of another example. It is a top view for demonstrating the mounting board using the reinforcing member of another example.

(Structure of Mounting Board Manufacturing Equipment)
Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. FIG. 1 shows a mounting substrate manufacturing apparatus 10. As shown in FIG. The mounting board manufacturing apparatus 10 includes a conveying device 20, a first shaping unit 22, a second shaping unit 24, a mounting unit 26, a third shaping unit 29, and a control device 27 (see FIGS. 2 and 3). Prepare. The conveying device 20 , the first shaping unit 22 , the second shaping unit 24 , the mounting unit 26 and the third shaping unit 29 are arranged on the base 28 of the mounting board manufacturing apparatus 10 . The base 28 has a generally rectangular shape in plan view. In the following description, the longitudinal direction of the base 28 is referred to as the X-axis direction, the lateral direction of the base 28 is referred to as the Y-axis direction, and the direction orthogonal 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 has an X-axis slide rail 34 and an X-axis slider 36 . The X-axis slide rail 34 is arranged on the base 28 so as to extend in the X-axis direction. The X-axis slider 36 is held by an X-axis slide rail 34 so as to be slidable in the X-axis direction. Further, the X-axis slide mechanism 30 has an electromagnetic motor 38 (see FIG. 2), and by driving the electromagnetic motor 38, the X-axis slider 36 is moved to an arbitrary position in the X-axis direction. The Y-axis slide mechanism 32 also has a Y-axis slide rail 50 and a stage 52 . The Y-axis slide rail 50 is arranged on the base 28 so as to extend in the Y-axis direction. One end of the Y-axis slide rail 50 is connected to the X-axis slider 36 . Therefore, the Y-axis slide rail 50 is movable in the X-axis direction. The stage 52 is held by a Y-axis slide rail 50 so as to be slidable in the Y-axis direction. The Y-axis slide mechanism 32 has an electromagnetic motor 56 (see FIG. 2), and drives the electromagnetic motor 56 to move the stage 52 to any position in the Y-axis direction. As a result, the stage 52 is moved to any position on the base 28 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 and an elevating device 64 . The base 60 is formed in a flat plate shape, and the base material 70 is mounted on the upper surface thereof. The holding devices 62 are provided on both sides of the base 60 in the X-axis direction. The holding device 62 holds the substrate 70 fixedly on the base 60 by sandwiching both edges in the X-axis direction of the substrate 70 placed on the base 60 . The lifting device 64 is arranged below the base 60 and lifts the base 60 in the Z-axis direction.

The first shaping unit 22 is a unit that shapes wiring on the base material 70 placed on the base 60 of the stage 52 , and has a first printing section 72 and a baking section 74 . The first printing unit 72 has an inkjet head 76 (see FIG. 2), and linearly ejects conductive ink onto the substrate 70 placed on the base 60 . Conductive ink is one example of a fluid containing metal particles of the present disclosure. The conductive ink contains, for example, nanometer-sized metal (silver, etc.) fine particles dispersed in a solvent as a main component, and is cured by being baked with heat. The conductive ink contains, for example, metal nanoparticles with a size of several hundred nanometers or less. The surface of the metal nanoparticles is coated with, for example, a dispersant to suppress aggregation in a solvent.

The inkjet head 76 ejects conductive ink from a plurality of nozzles by, for example, a piezo method using piezoelectric elements. Further, the device for ejecting conductive ink (fluid containing metal nanoparticles) is not limited to an inkjet head having a plurality of nozzles, and may be, for example, a dispenser having one nozzle. Also, the type of metal nanoparticles contained in the conductive ink is not limited to silver, and may be copper, gold, or the like. Moreover, the number of types of metal nanoparticles contained in the conductive ink is not limited to one type, and may be plural types.

The baking section 74 has an irradiation device 78 (see FIG. 2). The irradiation device 78 includes, for example, an infrared heater that heats the conductive ink ejected onto the substrate 70 . The conductive ink is baked by applying heat from an infrared heater to form wiring. The firing of the conductive ink here means, for example, by applying energy to evaporate the solvent and decompose the protective film of the metal nanoparticles, that is, the dispersant, so that the metal nanoparticles contact or fuse. This is a phenomenon in which the electrical conductivity increases. Then, the wiring can be formed by baking the conductive ink. Incidentally, the device for heating the conductive ink is not limited to the infrared heater. For example, the mounting substrate manufacturing apparatus 10 may include an infrared lamp, a laser irradiation device for irradiating the conductive ink with a laser beam, or a substrate 70 onto which the conductive ink is discharged, as a device for heating the conductive ink. An electric furnace for heating may be provided.

The second modeling unit 24 is a unit that models a resin layer on the base material 70 placed on the base 60 , and has a second printing section 84 and a curing section 86 . The second printing unit 84 has an inkjet head 88 (see FIG. 2) and ejects an ultraviolet curable resin onto the substrate 70 placed on the base 60 . An ultraviolet curable resin is a resin that is cured by irradiation with ultraviolet rays. The inkjet head 88 may eject the UV curable resin by, for example, a piezoelectric method using piezoelectric elements or a thermal method in which resin is heated to generate bubbles and ejected from a plurality of nozzles.

The curing section 86 has a flattening device 90 (see FIG. 2) and an irradiation device 92 (see FIG. 2). The flattening device 90 flattens the upper surface of the ultraviolet curable resin ejected onto the substrate 70 by the inkjet head 88 . The flattening device 90 makes the thickness of the UV curable resin uniform by, for example, scraping off excess resin with a roller or a blade while leveling the surface of the UV curable resin. Further, the irradiation device 92 has a mercury lamp or an LED as a light source, and irradiates the ultraviolet curing resin discharged onto the substrate 70 with ultraviolet rays. As a result, the ultraviolet curable resin discharged onto the substrate 70 is cured to form a resin layer.

The mounting unit 26 is a unit for placing electronic components on the substrate 70 placed on the base 60 , and has a supply section 100 and a mounting section 102 . The supply unit 100 has a plurality of tape feeders 110 (see FIG. 2) that feed taped electronic components one by one, and supplies the electronic components at each supply position. The electronic component is, for example, a sensor element such as a temperature sensor. Incidentally, the supply of electronic components is not limited to the supply by the tape feeder 110, and may be the supply by a tray.

The mounting section 102 has a mounting head 112 (see FIG. 2) and a moving device 114 (see FIG. 2). The mounting head 112 has a suction nozzle for sucking and holding the electronic component. The suction nozzle is supplied with negative pressure from a positive/negative pressure supply device (not shown), and sucks and holds the electronic component by sucking air. Then, the electronic component is released by supplying a slight positive pressure from the positive/negative pressure supply device. Further, the moving device 114 moves the mounting head 112 between the supply position of the tape feeder 110 and the substrate 70 placed on the base 60 . As a result, the mounting unit 102 holds the electronic component with the suction nozzle, and arranges the electronic component held with the suction nozzle on the base material 70 .

Also, the third modeling unit 29 is a unit that applies a conductive paste or an underfill resin onto the base material 70 placed on the base 60 . The conductive paste is, for example, a viscous fluid containing micro-sized metal particles (such as microfillers) in a resin adhesive. Micro-sized metal microparticles are, for example, flake-state metals (such as silver). The metal microparticles are not limited to silver, and may be gold, copper, or multiple types of metals. The adhesive contains, for example, an epoxy-based resin as a main component. The conductive paste is cured by heating and used for forming connection terminals to be connected to wiring, for example. A connection terminal is, for example, a bump connected to a component terminal of an electronic component, an external electrode connected to an external device, or the like.

The underfill resin is a resin used for encapsulating electronic components, and is mainly composed of epoxy resin, for example. Also, the underfill resin is, for example, a thermosetting resin that is cured by heat. As the underfill resin, an ultraviolet curable resin or the like that is cured by ultraviolet rays may be used.

The third modeling unit 29 also has a dispenser 130 as a device for discharging (applying) conductive paste and underfill resin. The device for applying the conductive paste or the underfill resin is not limited to the dispenser, and may be a screen printing device or a gravure printing device. Moreover, the mounted substrate manufacturing apparatus 10 may be provided with separate dispensers 130 for discharging the conductive paste and the underfill resin, or the same dispenser 130 may be used by switching. In addition, "application" in the present disclosure is a concept that includes an operation of ejecting a fluid from a nozzle or the like, an operation of applying a fluid onto an object by screen printing or gravure printing, an operation of applying a fluid with a pin or the like, and the like. be. The dispenser 130 dispenses a conductive paste or an underfill resin onto the substrate 70 or resin layer. The discharged conductive paste is heated and hardened by, for example, the baking section 74 of the first modeling unit 22 to form a connection terminal (external electrode, etc.). Further, the discharged underfill resin seals the electronic components by being heated and hardened by the baking unit 74, for example.

Here, the conductive paste contains, for example, metal microparticles with a size of several tens of micrometers or less. In the conductive paste, the adhesive (resin or the like) is cured by being heated, and the conductive paste is cured in a state where the metal flakes are in contact with each other. As described above, in the conductive ink, for example, the metal nanoparticles are fused together by heating to form an integrated metal, and the conductivity is higher than when the metal nanoparticles are only in contact with each other. On the other hand, the conductive paste is cured by bringing the micro-sized metal microparticles into contact with each other by curing the adhesive. For this reason, the resistance (electrical resistivity) of the wiring formed by curing the conductive ink is extremely small, for example, several to several tens of microΩ cm, while the resistance of the wiring formed by curing the conductive paste (several tens to several 1,000 microΩ cm). Therefore, the conductive ink is suitable for forming objects that require a low resistance value, such as low-resistance circuit wiring.

On the other hand, the conductive paste cures the adhesive at the time of curing, so that the adhesion to other members can be enhanced, and the adhesiveness to other members is superior to that of the conductive ink. The other member here is a member to which the conductive paste is applied by discharging or the like, and includes, for example, a resin layer, wiring, and component terminals of electronic components. Therefore, the conductive paste is suitable for molding objects requiring mechanical strength (such as tensile strength), such as connection terminals for fixing electronic components to resin layers. The mounting board manufacturing apparatus 10 of the present embodiment can manufacture a mounting board with improved electrical properties and mechanical properties by properly using such conductive ink and conductive paste and taking advantage of their properties.

Next, the configuration of the control device 27 of the mounting board manufacturing apparatus 10 will be described. As shown in FIGS. 2 and 3, the control device 27 includes a controller 120, a plurality of drive circuits 122, and a storage device 124. FIG. A plurality of drive circuits 122 include the electromagnetic motors 38 and 56, the holding device 62, the lifting device 64, the inkjet head 76, the irradiation device 78, the inkjet head 88, the flattening device 90, the irradiation device 92, the tape feeder 110, and the mounting head 112. , is connected to mobile device 114 (see FIG. 2). Furthermore, the drive circuit 122 is connected to the third modeling unit 29 (see FIG. 3).

The controller 120 comprises a CPU, ROM, RAM, etc., is mainly a computer, and is connected to a plurality of drive circuits 122 . The storage device 124 includes a RAM, a ROM, a hard disk, etc., and stores a control program 126 for controlling the mounting board manufacturing apparatus 10 . The controller 120 can control the operations of the conveying device 20, the first modeling unit 22, the second modeling unit 24, the mounting unit 26, the third modeling unit 29, etc. by executing the control program 126 with the CPU. . In the following description, the controller 120 executing the control program 126 to control each device may simply be referred to as "the device". For example, ``the controller 120 moves the stage 52'' means ``the controller 120 executes the control program 126, controls the operation of the carrier device 20 via the drive circuit 122, and moves the stage by the operation of the carrier device 20. "Move 52".

(Operation of Mounting Board Manufacturing Equipment)
The mounting board manufacturing apparatus 10 of the present embodiment manufactures a mounting board 171 (see FIGS. 15 and 16) including wiring, connection terminals, and electronic components as a modeled product with the above configuration. The structure, manufacturing procedure, and the like of the modeled product described below are examples. Also, for example, the control program 126 of the storage device 124 is set with three-dimensional data of each layer obtained by slicing the mounting board 171 at the time of completion. The controller 120 controls the first modeling unit 22 and the like based on the data of the control program 126 to eject and cure the ultraviolet curable resin or the like to form the mounting board 171 .

First, when the base material 70 is set on the base 60 of the stage 52 , the controller 120 shapes the mounting board 171 on the base material 70 while moving the stage 52 . As shown in FIG. 4 , a release film 133 that can be separated by heat, for example, is attached to the upper surface of the base material 70 , and a mounting substrate 171 (modeled object) is formed on the release film 133 . . The peeling film 133 is peeled from the substrate 70 together with the mounting substrate 171 by being heated. The method for separating the substrate 70 and the mounting substrate 171 is not limited to the method using the release film 133 . For example, a member (such as a support material) that melts due to heat may be placed between the base material 70 and the mounting substrate 171 to melt and separate. Alternatively, the mounting substrate 171 may be directly formed on the base material 70 without using a separating member such as the release film 133 .

When the base material 70 is set, the controller 120 forms the circuit board 141 on the release film 133 as shown in FIG. The controller 120 forms a resin layer 143 having wiring 145 and through holes 147 . The wiring pattern of the wiring 145 and the like are set in the data of the control program 126 stored in the storage device 124, for example. 5 schematically shows a cross section of the circuit board 141. As shown in FIG.

Specifically, for example, when forming the resin layer 143, the controller 120 performs a process of discharging the ultraviolet curable resin from the inkjet head 88 of the second modeling unit 24 onto the release film 133, and The resin layer 143 is formed by repeatedly executing the process of irradiating ultraviolet rays from the irradiation device 92 of the curing section 86 .

Specifically, as shown in FIG. 4, the controller 120 moves the stage 52 below the second modeling unit 24, controls the second printing unit 84, and causes the inkjet head 88 to eject the ultraviolet curable resin 135. Droplets are discharged in a thin film form on the release film 133 . The controller 120 controls the inkjet head 88 to eject the ultraviolet curable resin 135 to a position corresponding to the resin layer 143 . The curing unit 86 irradiates the thin film-like ultraviolet curable resin 135 with ultraviolet rays from the irradiation device 92 . As a result, a thin resin layer is formed on the release film 133 . Note that the controller 120 may appropriately perform a process of flattening the ultraviolet curable resin discharged in the form of a thin film by the flattening device 90 . The controller 120 adjusts the ejection position of the ultraviolet curable resin 135, and repeats the ejection of the ultraviolet curable resin 135, the flattening of the ultraviolet curable resin 135, and the irradiation of ultraviolet rays, thereby forming the resin layer 143. FIG.

In addition, the controller 120 appropriately executes the formation of the wiring 145 and the through holes 147 in the process of forming the resin layer 143 . When forming the wiring 145 , the controller 120 moves the stage 52 below the first modeling unit 22 . The controller 120 controls the first printing unit 72 to eject the conductive ink onto the release film 133, the resin layer 143, etc. by the inkjet head 76. FIG. The inkjet head 76 linearly ejects the conductive ink according to the wiring pattern. This wiring pattern is set in the control program 126 according to, for example, a modeled object to be manufactured.

Next, the controller 120 controls the baking unit 74 to heat the conductive ink ejected onto the release film 133 and the resin layer 143 by the infrared heater of the irradiation device 78 . By baking the conductive ink, the wiring 145 can be formed on the resin layer 143 as shown in FIG.

Also, when forming the through hole 147 , the controller 120 moves the stage 52 below the third modeling unit 29 . The controller 120 controls the third modeling unit 29 to discharge the conductive paste onto the release film 133, the resin layer 143, the wiring 145, etc. by the dispenser 130. FIG.

Next, the controller 120 controls the firing section 74 of the first modeling unit 22 to heat the discharged conductive paste with the infrared heater of the irradiation device 78 . By baking the conductive paste, through holes 147 can be formed in the resin layer 143 as shown in FIG. The controller 120 appropriately executes the formation of the resin layer 143 , the wiring 145 , and the through holes 147 to form the circuit board 141 .

The process of forming the circuit board 141 described above is an example. For example, the wiring 145 in the upper layer and the wiring 145 in the lower layer may be directly connected without forming the through hole 147 . Also, instead of the through-hole 147, a bar-shaped metal pin or the like may be used to ensure conduction between the wiring 145 in the lower layer and the wiring 145 in the upper layer. Also, the circuit board 141 may not be formed by three-dimensional lamination molding. For example, a circuit board 141 manufactured in advance using a photolithography method, an electroplating method, or the like may be used.

Next, the controller 120 forms wiring to be connected to electronic components on the circuit board 141 . The controller 120 moves the stage 52 below the first modeling unit 22, and as shown in FIG. The inkjet head 76 linearly ejects the conductive ink 137 according to the wiring pattern connected to the electronic component 161 shown in FIG. The controller 120 forms the wiring 149 shown in FIGS. 6 and 7 on the circuit board 141 by heating and baking the conductive ink 137 ejected onto the circuit board 141 with the infrared heater of the irradiation device 78 . .

FIG. 7 shows a state in which the circuit board 141 is viewed from above. In this embodiment, as shown in FIG. 14, as an example, a square circuit board 141 is formed in a plan view, and an electronic component 161 is mounted in the center of its upper surface 141A. The wiring 149 is formed, for example, at a position connecting the component terminal 163 of the electronic component 161 and the wiring 145 (see FIG. 6) of the circuit board 141 . Wiring 149 is formed to surround electronic component 161 .

Next, after forming the wiring 149, the controller 120 forms the reinforcing member 153 shown in FIGS. Here, when the mounting board 171 (see FIGS. 15 and 16) on which the electronic component 161 is mounted is formed by three-dimensional lamination molding, heat is applied to the circuit board 141 in the forming process. For example, the circuit board 141 is heated when the conductive ink or paste is fired to form the wiring 149 and bumps 155 (see FIG. 13) described later. When the circuit board 141 is heated, thermal stress is generated and the circuit board 141 is warped. This thermal stress can build up as heat is applied during the manufacturing process. In particular, when the electronic component 161 is mounted or when the circuit board 141 warps after mounting, the bumps 155 are partially swollen, cracked, or cut. The mounting board manufacturing apparatus 10 of the present embodiment forms the reinforcing member 153 that reinforces the position where the electronic component 161 is mounted by three-dimensional lamination molding, increases the rigidity of the circuit board 141, and reduces warpage.

Specifically, as shown in FIGS. 8 and 9, the controller 120 forms a reinforcing member 153 surrounding the placement position 151 where the component terminals 163 (see FIG. 14) of the electronic component 161 are to be placed. Specifically, the controller 120 ejects the ultraviolet curing resin 135 from the inkjet head 88 (see FIG. 4) of the second modeling unit 24 onto the circuit board 141 and the wiring 149 in a thin film. The controller 120 controls the inkjet head 88 to eject the ultraviolet curing resin 135 to the position corresponding to the reinforcing member 153 .

The controller 120 appropriately executes a process of flattening the discharged ultraviolet curable resin 135 by the flattening device 90 . Further, the controller 120 irradiates the discharged ultraviolet curing resin 135 with ultraviolet rays from the irradiation device 92 of the curing section 86 . The controller 120 repeats ejection of the ultraviolet curable resin 135 , flattening of the ultraviolet curable resin 135 , and irradiation of ultraviolet rays to form the reinforcing member 153 .

As shown in FIGS. 8 and 9 , the reinforcing member 153 has, for example, a square frame shape surrounding the placement position 151 and the electronic component 161 . When the circuit board 141 is viewed from above, the reinforcing member 153 has a square frame shape in which two walls extending in the vertical direction and end portions of the two walls extending in the horizontal direction are connected to each other. FIG. 10 shows a cross section taken along line II shown in FIG. As shown in FIG. 10 , a plurality of wirings 149 arranged at a predetermined pitch are partly filled with reinforcing members 153 . The gaps between the wirings 149 are filled with the ultraviolet curable resin of the reinforcing member 153 .

Next, after forming the reinforcing member 153 , the controller 120 forms bumps 155 to be connected to the component terminals 163 of the electronic component 161 . Specifically, the controller 120 moves the stage 52 below the third modeling unit 29 after forming the reinforcing member 153 . As shown in FIG. 11 , the controller 120 controls the third modeling unit 29 to discharge the conductive paste 157 onto the wiring 149 by the dispenser 130 . The controller 120 ejects the conductive paste 157 according to the position where the bump 155 is to be formed.

After discharging the conductive paste 157 , the controller 120 moves the stage 52 below the mounting unit 26 and mounts the electronic component by the mounting unit 102 . As shown in FIG. 12 , the mounting head 112 of the mounting unit 102 sucks and holds the electronic component 161 with the suction nozzle 159 and conveys it above the circuit board 141 . Mounting unit 102 arranges electronic component 161 sucked by suction nozzle 159 such that component terminals 163 of electronic component 161 are positioned on conductive paste 157 .

Then, the controller 120 heats and hardens the conductive paste 157 by the baking section 74 of the first modeling unit 22 to form bumps. As shown in FIGS. 13 and 14 , component terminals 163 of the electronic component 161 are electrically connected to wiring 149 via bumps 155 . That is, the electronic component 161 is mounted on the circuit board 141 . The bump 155 is formed on the wiring 149 arranged inside the reinforcing member 153 . In other words, the reinforcing member 153 is formed on the wiring 149 so as to partially penetrate the wiring 149 inward.

Here, the positions where the electronic component 161 and the component terminals 163 are mounted are surrounded by the reinforcing member 153 . By forming the square frame-shaped reinforcing member 153 in advance, it is possible to intentionally increase the partial thickness of the circuit board 141 and increase the rigidity of the portion surrounded by the reinforcing member 153 . Even if heat is applied when the bumps 155 are baked and thermal stress is applied to the circuit board 141 inside the reinforcing member 153, the reinforcing member 153 increases the rigidity, thereby suppressing warping. As a result, the occurrence of cracks in the bumps 155 and the wiring 149 can be suppressed. Moreover, by using three-dimensional layered manufacturing, the reinforcing member 153 can be formed at an arbitrary position, and after the circuit board 141 is formed, a necessary portion of the circuit board 141 can be reinforced.

Note that the controller 120 may remove excess resin on the wiring 149 before discharging the conductive paste 157 forming the bumps 155 . In the molding of the reinforcing member 153 , there is a possibility that excess ultraviolet curable resin 135 may adhere to the wiring 149 exposed inside the reinforcing member 153 . For this reason, the controller 120 may, for example, irradiate a laser or the like toward the wiring 149 exposed inside the reinforcing member 153 to remove excess resin residue on the wiring 149 . Thereby, the resistance at the connecting portion between the wiring 149 and the bump 155 can be reduced.

Next, the controller 120 fills the inside of the reinforcing member 153 with underfill resin. After mounting the electronic component 161 , the controller 120 moves the stage 52 below the third modeling unit 29 . The controller 120 controls the third modeling unit 29 to discharge the underfill resin inside the reinforcing member 153 by the dispenser 130 . After discharging the underfill resin, the controller 120 heats and hardens the underfill resin by the baking unit 74 of the first modeling unit 22, for example. As shown in FIGS. 15 and 16, the electronic component 161 is filled and sealed with an underfill resin 165 filled in the portion surrounded by the reinforcing member 153 . In this manner, the mounting board manufacturing apparatus 10 of the present embodiment can manufacture the mounting board 171 on which the electronic component 161 is mounted.

Therefore, as described above, in the manufacturing method of the mounting substrate 171 of the present embodiment, the step of forming the bumps 155 is performed after forming the reinforcing members 153 (see FIGS. 11 to 13). In the step of forming the bumps 155, the conductive paste 157 is applied on the wiring 149 inside the reinforcing member 153 (see FIG. 11). Then, the conductive paste 157 applied on the wiring 149 is heated and hardened by the baking section 74 of the first modeling unit 22 (see FIG. 13). According to this method, a reinforcing member 153 surrounding the electronic component 161 is formed, and then the bumps 155 are formed on the wiring 149 exposed inside the reinforcing member 153 . When the bump 155 is formed, the reinforcing member 153 can prevent the conductive paste 157 from flowing out to an unnecessary place. In addition, it is possible to suppress the occurrence of a situation in which the conductive paste 157 that has flowed out to unnecessary places hardens and causes connection failures of the bumps 155 and the wirings 149 .

Further, the reinforcing member 153 of the present embodiment is a frame-shaped member formed by connecting walls surrounding the arrangement position 151 (see FIG. 9) of the electronic component 161 when the circuit board 141 is viewed from above. According to this, walls surrounding the component terminal 163 (placement position 151 ) are formed, and the walls are connected to each other to form a frame-like wall as the reinforcing member 153 . By connecting the walls to each other, the strength of the reinforcing member 153 can be increased, and the rigidity of the circuit board 141 at the arrangement position 151 can be further increased.

In addition, in the manufacturing process of the mounting substrate 171 of the present embodiment, the inner side of the reinforcing member 153 is filled with the underfill resin 165 to seal the electronic component 161 . According to this, by filling the inside of the reinforcing member 153 with the underfill resin 165, the thickness of the resin at the position where the electronic component 161 is mounted is increased, and the reinforcing member 153 is supported by the underfill resin 165 from the inside. , the rigidity of the circuit board 141 can be further increased. Warping of the circuit board 141 can be suppressed, and the occurrence of poor connection due to cracking of the bumps 155 or the like can be suppressed more reliably. Further, when the underfill resin 165 sealing the electronic component 161 tries to flow out from the position where the electronic component 161 is mounted, the flowing underfill resin 165 can be blocked by the reinforcing member 153 . It is possible to suppress the underfill resin 165 from flowing out to an unnecessary portion, thereby suppressing the occurrence of poor connection and the like. In addition, it becomes easy to manage the flow of the underfill resin 165 when the underfill resin 165 is filled.

As shown in FIG. 15, in the height direction orthogonal to the upper surface 141A of the circuit board 141, the distance between the upper surface 141A and the reinforcing member 153 is greater than the first distance L1 from the upper surface 141A of the circuit board 141 to the upper end of the electronic component 161. The second distance L2 to the upper end is long. In other words, the reinforcing member 153 of this embodiment is formed to a position higher than the electronic component 161 mounted on the circuit board 141 . According to this, by forming the reinforcing member 153 to a position higher than the electronic component 161, the reinforcing member 153 is filled with the underfill resin 165, and a reinforcing plate, which will be described later, is fixed on the reinforcing member 153. , it is possible to perform further reinforcement.

For example, as shown in FIG. 17, a reinforcing plate 173 may be attached on the reinforcing member 153 . The reinforcing plate 173 is made of a material such as metal, glass, or ceramic that is more resistant to thermal change than the resin circuit board 141, for example. The reinforcing plate 173 has, for example, a square plate shape covering the upper surfaces of the underfill resin 165 and the reinforcing member 153 . A method for attaching the reinforcing plate 173 to the mounting substrate 171 is not particularly limited. For example, it may be fixed to the reinforcing member 153 or the underfill resin 165 using an adhesive, screws, or the like. For example, the controller 120 may form a screw hole in the reinforcing member 153 for fixing the reinforcing plate 173 in the step of forming the reinforcing member 153 . Further, the fixing of the reinforcing plate 173 may be performed manually by a person, or may be performed by the mounting board manufacturing apparatus 10 . For example, the mounting substrate manufacturing apparatus 10 may be provided with a robot arm, hold the reinforcing plate 173 with the robot arm, and fix the reinforcing plate 173 on the reinforcing member 153 and the underfill resin 165 .

Therefore, the manufacturing process of the mounting board 171 of the present embodiment may include a process of fixing the reinforcing plate 173 covering the upper surface of the electronic component 161 to the reinforcing member 153 . According to this, the rigidity of the circuit board 141 is further increased by the reinforcing plate 173 through the reinforcing member 153 by using a material that is less susceptible to thermal change than the circuit board 141 that is mainly made of resin. be able to. Warpage of the circuit board 141 can be more effectively reduced.

Incidentally, the reinforcing plate 173 may be made of resin, like the circuit board 141 . For example, the reinforcing plate 173 may be a member in which glass or the like is inserted inside the resin. Moreover, the reinforcing plate 173 may be attached to the underfill resin 165 or may be attached to both the reinforcing member 153 and the underfill resin 165 . Also, when the reinforcing plate 173 is attached to the reinforcing member 153 , the inside of the reinforcing member 153 may not be filled with the underfill resin 165 . Further, the member that reinforces the reinforcing member 153 is not limited to a plate-like member, and may be a rod-like member. For example, the reinforcing member 153 may be reinforced with a rod-shaped member that connects two opposing walls among the four walls of the reinforcing member 153 .

Also, the shape, structure, number of members, etc. of the mounting substrate 171 described above are examples. For example, in the mounting substrate 171 described above, the component terminals 163 are arranged below the electronic component 161 and the electronic component 161 is mounted on the upper surface 141A of the circuit board 141 and the wiring 149, but the present invention is not limited to this. For example, as shown in FIG. 18, the component terminal 163 and the wiring 149 may be connected by a bump 155 above the electronic component 161 . A reinforcing member 153 and a reinforcing plate 173 may be formed on the wiring 149 . For example, the electronic component 161 may be embedded in the circuit board 141, the component terminals 163 may be exposed on the upper surface 141A (see FIG. 7), and the bumps 155 and the wiring 149 may be formed thereon. Also in this case, by forming the reinforcing member 153 so as to surround the electronic component 161 and the component terminals 163, the warping of the circuit board 141 and the like can be suppressed. Further, as shown in FIG. 18, the inside of the reinforcing member 153 may not be filled with the underfill resin 165 (see FIG. 17). Therefore, the orientation, arrangement, etc. of the electronic component 161 and the component terminal 163 described above may be appropriately changed according to the structure of the mounting substrate 171, and the like.

Further, for example, as shown in FIGS. 19 and 20, recesses may be formed as reinforcing members. The reinforcing member 153 shown in FIGS. 15 and 16 is formed of walls surrounding the mounting position of the electronic component 161 . On the other hand, the reinforcing member 253 shown in FIGS. 19 and 20 has a shape in which the outer side of the portion surrounding the electronic component 161 is filled with the ultraviolet curable resin 135 .

Specifically, the reinforcement member 253 fills the wiring 149 arranged outside the portion surrounding the arrangement position 151 (see FIG. 9) where the component terminal 163 is arranged with the ultraviolet curable resin 135 . For example, in plan view of the circuit board 141, the reinforcing member 253 is formed on the upper surface 141A except for a square area surrounding the electronic component 161, the component terminals 163, and the like. The reinforcing member 253 has a square plate shape with a square hole formed in the center. In other words, the wire 149 is filled with the reinforcing member 253 outside the portion (square hole) where the electronic component 161 is surrounded by the reinforcing member 253 .

Further, the reinforcing member 253 exposes the upper surface 141A of the circuit board 141 surrounding the component terminal 163 and forms a recess having the upper surface 141A of the circuit board 141 as the bottom surface. This recess is filled with, for example, an underfill resin 165 . According to this, the reinforcing member 253 is formed as a member that fills the wiring 149 outside the arrangement position 151 (see FIG. 9) of the component terminal 163 . The thickness of the circuit board 141 outside the placement position 151 can be increased as a whole. By forming a concave portion whose bottom surface is the upper surface 141A of the circuit board 141 on which the electronic component 161 is arranged, the rigidity of the circuit board 141 at the arrangement position 151 can be further increased. It should be noted that the underfill resin 165 does not have to be filled into the concave portion of the reinforcing member 253 . In addition to the underfill resin 165 or instead of the underfill resin 165, a reinforcing plate 173 (see FIG. 17) may be attached to the reinforcing member 253.

Incidentally, in the above embodiments, the ultraviolet curable resin 135 is an example of a resin material. Conductive ink 137 is an example of a first metal fluid. The circuit board 141 is an example of a board. Bump 155 is an example of a connecting portion. Conductive paste 157 is an example of the second metal fluid. The process of FIG. 5 is an example of the first metal fluid application process. The process of FIGS. 6 and 7 is an example of the wiring forming process. The steps of FIGS. 8 and 9 are examples of the resin material coating step and the reinforcing member forming step. The process of FIG. 11 is an example of the second metal fluid application process. The process of FIG. 12 is an example of the electronic component placement process. 13 and 14 are an example of the mounting process. 15 and 16 are an example of the sealing process. FIG. 17 shows an example of the reinforcing plate fixing step.

As described above, the present embodiment described above has the following effects.
The manufacturing process of the mounting board 171 of the present embodiment includes the process of applying the conductive ink 137 on the circuit board 141 shown in FIG. 6 and 7 for forming the . In addition, the manufacturing process includes a step of applying an ultraviolet curable resin 135 to a position surrounding the arrangement position 151 where the component terminal 163 of the electronic component 161 is arranged and above the wiring 149, and a step of curing the applied ultraviolet curable resin 135. 8 and 9 of forming a reinforcing member 153 surrounding the placement location 151; 11 to apply a conductive paste 157 on the wiring 149 corresponding to the placement position 151; 12 for connecting the electronic component 161 and the wiring 149 via the . 13 and 14 for forming the bumps 155 by curing the conductive paste 157 applied on the wiring 149 and mounting the electronic component 161. FIG.

According to this, a reinforcing member 153 is formed of the ultraviolet curable resin 135 at a position surrounding the component terminal 163 (arrangement position 151 ) of the electronic component 161 and on the wiring 149 . Accordingly, by filling at least a portion of the wiring 149 and forming the reinforcing member 153 surrounding the electronic component 161 to increase the thickness of the circuit board 141 , the rigidity of the circuit board 141 at the arrangement position 151 can be increased. Further, by forming the reinforcing member 153 at the position where the wiring 149 is partly buried, the reinforcing member 153 and the component terminal 163 can be brought close to each other, thereby effectively suppressing the warping of the circuit board 141 at the arrangement position 151. be able to. Bulging and cracking of the bumps 155 can be suppressed, and the yield of connection of the electronic component 161 can be improved.

The present disclosure is not limited to the above-described embodiments, and can be implemented in various modes with various modifications and improvements based on the knowledge of those skilled in the art.
For example, in the above embodiments, the circuit board 141 including the wiring 145 and the through holes 147 was adopted as the board of the present disclosure, but the present invention is not limited to this. The substrate of the present disclosure may be a resin layer 143 without wiring 145 or through-holes 147 .
Further, in the above embodiment, the bumps 155 are formed after the reinforcing members 153 are formed in FIG. However, the reinforcing member 153 may be formed after forming the bumps 155 first (after mounting the electronic component 161). In this case, the bumps 155 may be filled with the UV curable resin 135 forming the reinforcing member 153 and the bumps 155 may be filled with the reinforcing member 153 .

Also, the second distance L2 may be equal to or less than the first distance L1. For example, the reinforcing member 153 may be a wall that is lower than the upper end of the electronic component 161 .
Further, in the above embodiment, an ultraviolet curable resin that is cured by irradiation with ultraviolet rays is used, but various curable resins such as a thermosetting resin that is cured by heat can be used.
In addition, the method of three-dimensional layered manufacturing in the present disclosure is not limited to the inkjet method or stereolithography (SL: Stereo Lithography), and other methods such as Fused Deposition Molding (FDM) are adopted. can.

135 UV curable resin (resin material), 137 conductive ink (first metal fluid), 141 circuit board (substrate), 141A upper surface, 149 wiring, 151 arrangement position, 153, 253 reinforcing member, 155 bump (connecting portion), 157 conductive paste (second metal fluid), 161 electronic component, 163 component terminal, 165 underfill resin, 171 mounting board, 173 reinforcing plate, L1 first distance, L2 second distance.

Claims (7)

A method for manufacturing a mounting board in which a plurality of wirings and a plurality of component terminals of an electronic component are connected at a plurality of connection portions by three-dimensional lamination molding,
a first metal fluid coating step of coating a substrate with a first metal fluid in which metal particles are dispersed in a solvent ;
a wiring forming step of curing the first metal fluid applied onto the substrate to form a plurality of wirings;
a resin material applying step of applying a resin material to a position surrounding each of the plurality of component terminals of the electronic component and on each of the plurality of wirings;
a reinforcing member forming step of curing the resin material applied on each of the plurality of wirings to form a reinforcing member surrounding the arrangement position;
a second metal fluid applying step of applying a second metal fluid, which is a viscous fluid containing metal particles, onto each of the plurality of wirings corresponding to the arrangement positions;
an electronic component arranging step of arranging the plurality of component terminals of the electronic component at the arrangement position and connecting each of the plurality of component terminals of the electronic component to the plurality of wirings via the second metal fluid;
a mounting step of heating and curing the second metal fluid applied to each of the plurality of wirings to form the plurality of connection portions, and mounting the electronic component;
A method for manufacturing a mounting substrate by three-dimensional lamination molding. After forming the reinforcing member by the reinforcing member forming step, performing the second metal fluid applying step,
In the second metal fluid applying step,
2. The method of manufacturing a mounting substrate by three-dimensional layered manufacturing according to claim 1, wherein the second metal fluid is applied onto the wiring of the wiring that is inside the reinforcing member. The reinforcing member is
3. The three-dimensional layered manufacturing according to claim 1 or 2, wherein a frame-shaped member is formed by connecting walls surrounding the arrangement positions of the plurality of component terminals when the substrate is viewed from above. A method for manufacturing a mounting substrate. The reinforcing member is
The plurality of wirings arranged outside the portion surrounding the arrangement position is filled with the resin material, and the upper surface of the substrate in the portion surrounding the arrangement position is exposed to form a recess having the upper surface of the substrate as the bottom surface. 3. The method of manufacturing a mounting substrate by three-dimensional lamination molding according to claim 1 or 2, wherein the member is a member for manufacturing. A second distance from the upper surface of the substrate to the upper end of the reinforcing member is longer than a first distance from the upper surface of the substrate to the upper end of the electronic component in a height direction orthogonal to the upper surface of the substrate. The method of manufacturing a mounting substrate by three-dimensional lamination molding according to any one of claims 1 to 4. 6. The method of manufacturing a mounting substrate by three-dimensional lamination molding according to claim 5, further comprising a sealing step of filling an underfill resin inside the reinforcing member to seal the electronic component. 7. The method of manufacturing a mounting board by three-dimensional lamination molding according to claim 5, further comprising a reinforcing plate fixing step of fixing a reinforcing plate covering the upper surface of the electronic component to the reinforcing member.

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