JP2015012158A - Electronic apparatus and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus which has a structure the size of which can be suppressed and in which internal observation of a mold resin by an ultrasonic flaw detection device can be more excellently performed.SOLUTION: At an end of a mold resin 40, a portion of the mold resin 40 whose thickness is made thin is provided, and this portion is gradually made thin toward the outer side of the mold resin 40 to be a taper part 41. In this structure, at a termination of the mold resin 40, stress due to a thermal expansion coefficient difference between the mold resin 40 and a substrate 10 can be alleviated since there is no sudden change from a region in which the thick mold resin 40 is formed to a region in which the thick mold resin 40 is not formed. With this, separation between the mold resin 40 and the substrate 10 can be suppressed. Also, there is a small region to be the taper part 41. Therefore, the internal observation by an ultrasonic flaw detection device can be excellently performed in most of the region of the mold resin 40. Consequently, the internal observation of the mold resin can be more excellently performed.

Description

  The present invention relates to an electronic device in which an electronic component is mounted on one surface side of a substrate and the one surface side is sealed with a mold resin, and a manufacturing method thereof.

  Conventionally, there is an electronic device in which an electronic component is mounted on one side of a substrate. In this electronic device, a surface pattern that is electrically connected to a land and an external circuit is formed on one surface of a substrate, and a solder resist that covers the surface pattern is formed. The solder resist has an opening for exposing a portion of the surface pattern connected to an external circuit. The electronic component is mounted on a land formed on one surface of the substrate via solder or the like. One surface side of the substrate including the electronic component is sealed with a mold resin so that at least a portion of the surface pattern connected to the external circuit is exposed.

  Such an electronic device is manufactured as follows. Specifically, first, a land and a surface pattern are formed on one surface of the substrate. And after forming the solder resist which covers a surface pattern, the opening part which exposes a part of surface pattern to a solder resist is formed. Next, an electronic component is mounted on the land via solder or the like. Subsequently, a mold having a recess formed on one surface is prepared, and one surface of the mold is pressed against one surface of the substrate so that the electronic component is disposed in the recess. Thereafter, a space between the substrate and the concave portion of the mold is filled with mold resin, whereby a single-sided mounting (half mold) electronic device in which one surface side of the substrate including the electronic component is sealed is manufactured.

  In the electronic device having such a structure, a thick mold resin is formed when the side wall surface (end surface) of the mold resin is a surface perpendicular to the substrate on the side where the substrate protrudes beyond the resin. The region suddenly changes to a region where no mold resin is formed. For this reason, peeling between mold resin and a substrate arises based on the stress resulting from the thermal expansion coefficient difference of mold resin and a substrate.

  In order to prevent this, as shown in Patent Document 1, the mold resin has a trapezoidal cross section, and the mold resin extends from the upper surface of the mold resin, that is, from the surface opposite to the substrate to the surface that is in close contact with the substrate. The side wall surface of the substrate may be tapered with respect to the substrate. With such a structure, since the thickness of the mold resin gradually decreases toward the outside of the mold resin at the end portion of the mold resin, the stress gradually decreases. Therefore, the stress generated in this region can be relaxed, and peeling between the mold resin and the substrate can be suppressed. In addition, by adopting such a structure, it is possible to improve the mold release property when removing the mold resin from the mold as compared with the case where the side wall surface of the mold resin is perpendicular to the substrate. Become.

JP 2011-18856 A

  However, as shown in Patent Document 1, when the side wall surface of the mold resin is tapered from the upper surface of the mold resin to the surface to be in close contact with the substrate, the area of the tapered region increases. Since this tapered region is a dead space in which electronic components cannot be placed, an increase in the area of this region leads to an increase in the size of the electronic device. In addition, when performing internal observation with an ultrasonic flaw detector, the internal observation is performed by emitting ultrasonic waves perpendicular to the surface of the mold resin, but the ultrasonic waves are not reflected vertically in the tapered portion, Internal observation is not possible. For this reason, if the tapered region is wide, the region where the internal observation cannot be performed increases, and the internal observation of the mold resin cannot be performed satisfactorily.

  An object of the present invention is to provide an electronic device having a structure capable of suppressing an increase in size and capable of better performing internal observation of a mold resin by an ultrasonic flaw detector and a method for manufacturing the same. And

  In order to achieve the above object, according to the first to fourth aspects of the present invention, the substrate (10) having one surface (11) and the other surface (12) opposite to the one surface is mounted on one surface of the substrate. Electronic components (20, 30) and a mold resin (40) provided on one surface side of the substrate for sealing the electronic components, and at least a part of the substrate is disposed to the outside of the mold resin. In the portion where the substrate is arranged to the outside of the mold resin, the mold resin includes a mold resin having a lower surface on one side of the substrate and an upper surface on the side opposite to the lower surface. Also, the taper portion that protrudes from the lower surface side toward the outside of the mold resin, is inclined with respect to one surface, and gradually decreases in height from the one surface toward the outside of the mold resin. ( It is characterized in that 1) is provided.

  As described above, the end portion of the mold resin is provided with a portion where the thickness of the mold resin is reduced, and the taper portion is formed by gradually decreasing the thickness toward the outside of the mold resin. For this reason, in the terminal part of mold resin, since it does not change suddenly from the area where the thick mold resin is formed to the area where it is not formed, the stress caused by the difference in thermal expansion coefficient between the mold resin and the substrate is applied. Can be relaxed. Thereby, it becomes possible to suppress peeling between the mold resin and the substrate. Further, since the tapered portion is not formed from the upper surface of the mold resin to one surface of the substrate, there are few regions that become the tapered portion. For this reason, internal observation by an ultrasonic flaw detector can be performed in almost all regions of the mold resin. Therefore, it becomes possible to better observe the inside of the mold resin.

  A fifth aspect of the invention corresponds to the electronic device manufacturing method according to the first to fourth aspects. Specifically, in the invention according to claim 5, in the case where the mold resin is formed by molding, the inner wall surface constituting the cavity of the second mold is the second mold (92) in which the cavity is formed. By using a taper with a cavity that gradually expands toward one surface of the substrate, the mold resin has a side surface of the mold, with one surface of the substrate being the lower surface and the opposite surface to the upper surface. The taper portion 41 protrudes outward from the lower surface side of the upper surface of the mold resin, is inclined with respect to one surface of the substrate, and gradually decreases in thickness toward the outer surface of the mold resin. ). Accordingly, the electronic device according to any one of claims 1 to 4 can be manufactured, the peeling between the mold resin and the substrate can be suppressed, and the internal observation by the ultrasonic flaw detector can be performed. It is possible to manufacture an electronic device that can be satisfactorily performed in almost all areas.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

1 is a cross-sectional view of an electronic device according to a first embodiment of the present invention. It is II-II arrow sectional drawing in FIG. It is an enlarged view of the area | region R in FIG. It is a cross-sectional schematic diagram in the case of manufacturing the mold resin 40 in the electronic device shown in FIG. 1 by compression molding. It is sectional drawing to which the part corresponding to the area | region R in FIG. 1 was expanded about the electronic device concerning 2nd Embodiment of this invention. It is sectional drawing to which the part corresponding to the area | region R in FIG. 1 was expanded about the electronic device concerning 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
With reference to FIGS. 1-3, the whole structure of electronic device S1 concerning 1st Embodiment of this invention is demonstrated. The electronic device S1 is mounted on a vehicle such as an automobile, and is applied as a device for driving each device for the vehicle.

  As shown in FIGS. 1 and 2, the electronic device S <b> 1 is configured to include a substrate 10, electronic components 20 and 30, a mold resin 40, a heat sink 50, a case 60, a lid 70, and a heat dissipation gel 80.

  As shown in FIG. 1, the substrate 10 is a plate-like member having one surface 11 on which the electronic components 20 and 30 are mounted and covered with the mold resin 40 and the other surface 12 which is the opposite surface. is there. In the present embodiment, the substrate 10 is a plate-like member having a rectangular top surface as shown in FIG. Specifically, the substrate 10 is a wiring substrate based on a resin such as an epoxy resin, and is configured by, for example, a through substrate or a build-up substrate.

  A wiring pattern (not shown) constituted by an inner layer wiring or a surface layer wiring is formed on the substrate 10, and the wiring pattern is extended to the outside of the mold resin 40, so that the electronic components 20, 30 can be connected to the substrate 10 through the wiring pattern. The electrical connection can be achieved. In addition, on both sides of the substrate 10 in the longitudinal direction (left-right direction in FIG. 1), through holes 13 provided with metal plating or the like connected to the wiring pattern are provided. Through this through hole 13, the wiring pattern can be electrically connected to the outside of the substrate.

  The substrate 10 thus configured is supported by the case 60 at the four corners. In the case of the present embodiment, fixing holes 14 serving as through holes are formed at the four corners of the substrate 10, and after mechanical connection portions 64 protruding from the bottom surface 61 of the case 60 are fitted therein, the mechanical holes 64 are mechanically inserted. The substrate 10 is supported on the case 60 by heat caulking the tip of the connecting portion 64.

  The electronic components 20 and 30 are electrically connected to the wiring pattern by being mounted on the substrate 10, and may be any surface mounting component or through-hole mounting component. In the case of the present embodiment, the semiconductor element 20 and the passive element 30 are exemplified as the electronic components 20 and 30. Examples of the semiconductor element 20 include a power element that generates a large amount of heat, such as a microcomputer, a control element, an IGBT (Insulated Gate Bipolar Transistor), or a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). The semiconductor element 20 is connected to a land connected to the wiring pattern of the substrate 10 or a land formed by a part of the wiring pattern by a bonding wire 21 and a die bonding material 22 such as solder. Examples of the passive element 30 include a chip resistor, a chip capacitor, and a crystal resonator. The passive element 30 is connected to a land provided on the substrate 10 by a die bonding material 31 such as solder. With these configurations, the electronic components 20 and 30 are electrically connected to the wiring pattern formed on the substrate 10 and can be electrically connected to the outside through the through holes 13 connected to the wiring pattern.

  The mold resin 40 is composed of a thermosetting resin such as an epoxy resin, and is formed by a transfer molding method using a mold or a compression molding method. In the case of the present embodiment, a so-called half mold structure is formed in which the one surface 11 side of the substrate 10 is sealed with the mold resin 40 and the other surface 12 side of the substrate 10 is exposed without being sealed with the mold resin 40. . In the present specification, in the mold resin 40, the one surface 11 side of the substrate 10 is referred to as a lower surface, and the opposite side is referred to as an upper surface. Here, the upper surface of the mold resin 40 is a flat surface. However, the upper surface is not necessarily a flat surface. For example, the center line may have a roof shape or a curved surface shape with the highest height from the first surface 11. Unevenness may be formed.

  Further, as shown in FIG. 2, the mold resin 40 has a rectangular top surface, and the two opposite sides of the substrate 10, specifically, both sides perpendicular to the longitudinal direction of the substrate 10 are exposed. It is formed only on the inner side than both sides. That is, both ends in the longitudinal direction of the substrate 10 protrude from the mold resin 40 and are exposed from the mold resin 40 by being arranged to the outside. A through hole 13 is disposed in a portion exposed from the mold resin 40, and an electrical connection between the wiring pattern formed on the substrate 10 and the outside is possible through the through hole 13. Further, both sides of the substrate 10 are exposed from the mold resin 40, so that the four corners of the substrate 10 are exposed. In the portion exposed from the mold resin 40, the substrate 10 is attached to the case 60 as described above. It is supported.

  Further, as shown in FIG. 3, a taper portion 41 protruding in a tapered shape is provided on a part of the side surface of the mold resin 40, specifically, a portion of the side surface on the one surface 11 side of the substrate 10. The side surface of the mold resin 40 is provided with a taper portion 41 by being inclined with respect to the one surface 11 at a portion on the upper surface side of the mold resin 40 and inclined with respect to the one surface 11 at a portion on the one surface 11 side. In other words, the end portion of the mold resin 40 is provided with a portion where the thickness of the mold resin 40 from the lower position than the upper surface of the mold resin 40 is reduced, and gradually toward the outside of the mold resin 40. The tapered portion 41 is formed by making it thinner. That is, the taper portion 41 is configured by gradually lowering the height from the one surface 11 of the mold resin 40 toward the outside of the mold 40. In the case of the present embodiment, the surface of the taper portion 41 is a flat surface, and is inclined at an arbitrary angle with respect to the one surface 11, and at an arbitrary angle with respect to a portion other than the taper portion 41 on the side surface of the mold resin 40. The structure is inclined.

  The thickness of the mold resin 40 in the tapered portion 41 is set lower than that of the electronic components 20 and 30 having the highest height from the one surface 11 in the substrate 10. For this reason, the area | region where thickness is thin among the mold resin 40 is limited, and the height of the mold resin 40 from the one surface 11 covers the electronic components 20 and 30 also in the vicinity of the outer edge part of the mold resin 40. It is height.

  And by providing the taper part 41, it is made for the thickness of the mold resin 40 to become thin gradually as it goes to the outward of the mold resin 40. As shown in FIG. For this reason, in the terminal part of mold resin 40, since it does not change suddenly from the area where thick mold resin 40 is formed to the area where it is not formed, the difference in thermal expansion coefficient between mold resin 40 and substrate 10 occurs. The resulting stress can be relaxed. Thereby, peeling between the mold resin 40 and the substrate 10 can be suppressed. Further, since the tapered portion 41 is not formed so as to extend from the upper surface of the mold resin 40 to the one surface 11 of the substrate 10, there are few regions that become the tapered portion 41. For this reason, the internal observation by the ultrasonic flaw detector can be satisfactorily performed in most regions of the mold resin 40. Therefore, the inside observation of the mold resin 40 can be performed more favorably.

  For the two sides of the mold resin 40 having a rectangular shape located above and below the paper surface in FIG. 2, the position of the side surface of the mold resin 40 coincides with the position of the side surface of the substrate 10. As for the portion, the side surface of the mold resin 40 is flat and is flush with the side surface of the substrate 10. As described above, when the side surface of the mold resin 40 and the side surface of the substrate 10 are on the same plane, the stress received from the mold resin 40 to the outer edge portion of the substrate 10 is uniform. For this reason, even if the taper part 41 is not provided in this part, the problem of peeling between the mold resin 40 and the substrate 10 hardly occurs.

  The heat sink 50 is made of a metal material having a high heat transfer rate, such as aluminum or copper, and is in close contact with the other surface 12 side of the substrate 10 via a bonding member 51. As the joining member 51, for example, a conductive adhesive containing a metal filler, a conductive material such as a solder material, or an insulating material such as a heat radiating gel or a heat radiating sheet is used. The heat sink 50 plays a role of radiating heat when the heat generated by the electronic components 20 and 30 is transmitted from the other surface 12 side of the substrate 10 and is made of a metal material having high thermal conductivity, such as copper. Has been. In particular, when the semiconductor element 20 is composed of an IGBT or a MOSFET, since these are heating elements, they generate a lot of heat, but this heat is transmitted to the heat sink 50, so that the semiconductor elements 20 and the passive elements 30 High temperature is suppressed. In the case of the present embodiment, the heat sink 50 is thermally connected to the lid 70 via the heat radiating gel 80, and heat transferred from the back surface of the substrate 10 is further transmitted to the lid 70 through the heat radiating gel 80. Heat is radiated from 70 to the outside.

  The case 60 is a rectangular housing that accommodates the electronic components 20, 30 mounted on the one surface 11 side of the substrate 10 and sealed with the mold resin 40. In the case of the present embodiment, the case 60 is a member constituting the housing recess 63 in which the periphery of the bottom surface 61 is covered by the side wall surface 62, and the substrate 10 mounted with the electronic components 20 and 30 and sealed with the mold resin 40 is used. In the housing recess 63, the one surface 11 side faces the bottom surface 61 side.

  As described above, the mechanical connection portion 64 that supports the substrate 10 is formed on the bottom surface 61 of the case 60. The mechanical connection portion 64 is a stepped rod-like member that protrudes in the vertical direction from the bottom surface 61 and whose sectional dimensions are partially changed. Specifically, in the state before the substrate 10 is fixed, the mechanical connection portion 64 has a cross-sectional dimension on the bottom side larger than that of the fixing hole 14 formed in the substrate 10, and a cross-sectional dimension on the tip side is larger than the fixing hole 14. Is almost the same or slightly smaller. Because of such dimensions, the mechanical connection portion 64 holds the substrate 10 at the stepped portion between the front end side and the bottom surface side while the front end side is inserted into the fixing hole 14. Then, the front end side of the mechanical connection portion 64 is fitted into the fixing hole 14 and then heat caulked, so that a portion protruding from the substrate 10 has a cross-sectional dimension larger than that of the fixing hole 14 and a step difference from that portion. The substrate 10 is sandwiched between and supported.

  The protruding amount of the mechanical connection portion 64 is set to be lower than the height of the side wall surface 62 so that the substrate 10 enters the inside of the housing recess 63 rather than the tip of the side wall surface 62.

  Further, a plurality of connection terminals 65 are erected on the bottom surface 61 of the case 60 in a direction perpendicular to the bottom surface 61. For example, each connection terminal 65 is made of a copper alloy that is tin-plated or nickel-plated. Each of the plurality of connection terminals 65 is inserted through a through hole 13 formed in the substrate 10 and is electrically connected to the through hole 13 via a connection member 15 such as solder. The case 60 is basically made of an insulator based on a resin such as PPS (polyphenylene sulfide) or PBT (polybutylene terephthalate), but includes a wiring pattern extending to the outside of the case 60. Yes. A plurality of connection terminals 65 are connected to the wiring pattern, and the wiring pattern of the substrate 10 on which the electronic components 20 and 30 are mounted is electrically connected to the outside through the connection terminals 65 and the wiring pattern. Yes.

  The lid 70 seals the inside of the case 60 by being connected to the opening end of the case 60, that is, the tip of the side wall surface 62. The lid 70 is fixed to the case 60 via an adhesive or the like, for example. In the case of this embodiment, the lid 70 is made of a metal material having a high heat transfer coefficient, such as aluminum or copper, and is made of a rectangular plate-like member.

  The heat dissipating gel 80 is disposed between the heat sink 50 and the lid 70, and is disposed so as to be in contact with both, thereby transferring heat from the heat sink 50 to the lid 70. For example, the heat radiating gel 80 is made of a silicone oil compound having a high thermal conductivity. Although it is possible to eliminate the heat-dissipating gel 80 and make the structure in which the heat sink 50 and the lid 70 are in direct contact with each other, it is difficult to adjust the height of the heat sink 50 and the heat sink 50 may be pressed when the lid 70 is fixed. For this reason, it is preferable to provide a heat-dissipating gel 80 that can be deformed.

  As described above, the electronic device S1 according to the present embodiment is configured. Such an electronic device S1 is manufactured by the following manufacturing method.

  First, after preparing the substrate 10 on which the wiring pattern and the through hole 13 are formed, the electronic components 20 and 30 are mounted on the one surface 11 of the substrate 10. Next, the substrate 10 on which the electronic components 20 and 30 are mounted is sealed with a mold resin 40 by a transfer molding method or a compression molding method.

  FIG. 4 shows a state in which resin sealing with the mold resin 40 is performed, for example, by compression molding. As shown in this figure, a lower mold (first mold) 91, an upper mold (second mold) 92, and a plunger 93 are used as a mold 90 serving as a mold. First, the substrate 10 is placed on the lower mold 91. It arrange | positions so that the other surface 12 side may face the lower mold | type 91 side. Subsequently, after the upper die 92 is arranged, the resin powder used for compression molding is filled in the opening 92a of the upper die 92, and then the plunger 93 is slid in the opening 92a and heated and pressurized. Perform molding. Thereby, the mold resin 40 is formed.

  At this time, on the side of the upper die 92 that contacts the one surface 11 of the substrate 10, the inner wall surface is tapered so that the cavity gradually widens toward the one surface 11. For this reason, a tapered portion 41 is formed in a portion of the side surface of the mold resin 40 on the one surface 11 side so that the thickness of the mold resin 40 gradually decreases as the mold resin 40 moves outward.

  Then, after the heat sink 50 is bonded to the other surface 12 side of the substrate 10 via the bonding member 51, the substrate 10 is disposed in the housing recess 63 of the case 60 with the one surface 11 side facing the bottom surface 61 side. At this time, the plurality of connection terminals 65 are inserted into the through holes 13 so that the tips of the mechanical connection portions 64 are fitted into the fixing holes 14.

  Thereafter, the tip of the mechanical connection portion 64 is heat caulked, and the through hole 13 and the plurality of connection terminals 65 are connected by the connection member 15 by soldering or the like. Finally, after disposing the heat radiating gel 80 on the surface of the heat sink 50, the lid 70 is disposed thereon, and the space between the lid 70 and the side wall surface 62 of the case 60 is fixed with an adhesive or the like. The electronic device S1 is completed.

  If the entire side surface of the mold resin 40 is tapered from the upper surface of the mold resin 40 to the surface to be brought into close contact with the substrate 10 as in the prior art, if the mold resin 40 is formed by compression molding, the plunger 93 It is difficult to adjust the push-in amount. That is, the plunger 93 may be pushed too much, or conversely, the pushing amount of the plunger 93 may be insufficient. For this reason, the shape of the upper surface of the mold resin 40 changes according to the pushing amount of the plunger 93, and it is difficult to stably form a trapezoidal cross section, and the mold resin 40 extends from the upper surface of the mold resin 40 to the surface in contact with the substrate 10. It is difficult to taper the entire side surface. When the plunger 93 is pushed too much, a resin-pointed burr is formed at the outer edge portion of the upper surface side of the mold resin 40, which causes a problem that it is chipped in a subsequent process. Therefore, it can be said that the structure in which the entire side surface of the mold resin 40 is tapered from the upper surface of the mold resin 40 to the surface to be brought into close contact with the substrate 10 is not suitable for compression molding.

  On the other hand, in the present embodiment, only the portion on the one surface 11 side of the side surface of the mold resin 40 is tapered. For this reason, regardless of the pushing amount of the plunger 93, the shape of the upper surface of the mold resin 40 does not change, and no burrs are generated due to the plunger 93 being pushed too much. Therefore, the mold resin 40 can be stably formed in the same shape, and the problem that burrs are lost in a subsequent process does not occur.

  As described above, in the electronic device S <b> 1 according to the present embodiment, the end portion of the mold resin 40 is provided with a portion in which the thickness of the mold resin 40 is reduced, and as it goes outward of the mold resin 40. The taper portion 41 is formed by gradually reducing the thickness. For this reason, in the terminal part of mold resin 40, since it does not change suddenly from the area where thick mold resin 40 is formed to the area where it is not formed, the difference in thermal expansion coefficient between mold resin 40 and substrate 10 occurs. The resulting stress can be relaxed. Thereby, peeling between the mold resin 40 and the substrate 10 can be suppressed. Further, since the tapered portion 41 is not formed so as to extend from the upper surface of the mold resin 40 to the one surface 11 of the substrate 10, there are few regions that become the tapered portion 41. For this reason, the internal observation by the ultrasonic flaw detector can be satisfactorily performed in most regions of the mold resin 40. Therefore, it becomes possible to better observe the inside of the mold resin.

  Further, the tapered portion 41 is not formed in the entire region from the upper surface of the mold resin 40 to the one surface 11 of the substrate 10, and is formed from below the upper surface of the mold resin 40. Can be limited. For this reason, the electronic components 20 and 30 can be disposed up to the vicinity of the outer edge portion of the mold resin 40, the dead space can be reduced, and the enlargement of the electronic device S1 can be suppressed.

(Second Embodiment)
A second embodiment of the present invention will be described. In the present embodiment, the shape of the tapered portion 41 is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only the parts different from the first embodiment will be described.

  As shown in FIG. 5, in this embodiment, the boundary position between the portion other than the taper portion 41 and the taper portion 41 in the side surface of the mold resin 40 and the boundary position between the taper portion 41 and one surface of the substrate 10 are R-shaped. It is designed to be a curved surface. Thus, even if the surface of the taper portion 41 is curved, the same effect as that of the first embodiment can be obtained. In addition, by making the surface of the tapered portion 41 a curved surface, the stress caused by the difference in thermal expansion coefficient between the mold resin 40 and the substrate 10 at each boundary position can be changed smoothly. Thereby, it becomes possible to further suppress peeling between the mold resin 40 and the substrate 10.

(Third embodiment)
A third embodiment of the present invention will be described. In the present embodiment, the shape of the taper portion 41 is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only different portions from the first embodiment will be described.

  As shown in FIG. 6, in this embodiment, the boundary position between the portion other than the taper portion 41 and the taper portion 41 in the side surface of the mold resin 40 is an R-shaped curved surface. As described above, even if the boundary position between the taper portion 41 and the portion other than the taper portion 41 on the side surface of the mold resin 40 is curved, the same effect as that of the first embodiment can be obtained. Moreover, the stress resulting from the difference in thermal expansion coefficient between the mold resin 40 and the substrate 10 at the boundary position can be changed smoothly. Thereby, it becomes possible to further suppress peeling between the mold resin 40 and the substrate 10.

(Other embodiments)
The present invention is not limited to the embodiment described above, and can be appropriately changed within the scope described in the claims.

  For example, in each of the embodiments described above, an example of the electronic device S1 to which the electronic components 20 and 30 are mounted on the one surface 11 of the substrate 10 and then the electronic components 20 and 30 are sealed with the mold resin 40 is applied. Although shown, it does not have to be the structure described in the above embodiments. For example, the one surface 11 side of the substrate 10, that is, the mold resin 40 side is arranged to face the bottom surface 61 side of the case 60, but the other surface 12 side, that is, the side opposite to the mold resin 40 is directed to the bottom surface 61 side. You may arrange in.

  Further, the formation position of the taper portion 41 is not limited to the shape described in each of the above embodiments as long as it is formed from a position below the upper surface of the mold resin 40. For example, in each of the above embodiments, in order to further reduce the dead space, the tapered portion 41 is provided from a position lower than the highest one of the electronic components 20 and 30. Alternatively, the tapered portion 41 may be formed from the upper position. Furthermore, in the third embodiment, only the boundary position between the taper portion 41 and the portion other than the taper portion 41 of the side surface of the mold resin 40 is a curved surface, but only the boundary position between the taper portion 41 and one surface of the substrate 10 is used. It may be a curved surface.

  Furthermore, in the case where a plurality of substrates 10 are manufactured from a multiple substrate, that is, a single base material, a plurality of mold resins 40 may be formed simultaneously. In this case, it is possible to form the plurality of substrates 10 by forming the mold resin 40 so as to straddle the plurality of substrates 10 and cutting the multiple substrate together with the mold resin 40. The side surface of the mold resin 40 and the side surface of the substrate 10 are flush with each other. Therefore, even when a plurality of substrates 10 are formed using a multiple substrate in this way, the substrate 10 and the mold resin 40 having the structure described in the above embodiments can be manufactured. In this case, since the taper portions 41 can be formed on all sides of the mold resin 40 in a state before cutting, it is possible to further improve the mold release properties at the time of molding.

  Further, the method of fixing the substrate 10 by the mechanical connection portion 64 is not limited to heat caulking, and may be press-fitting or screw-tightening. Further, the connection between the connection terminal 65 and the through hole 13 is not limited to soldering, and may be a press fit or the like.

DESCRIPTION OF SYMBOLS 10 Board | substrate 11 One side 12 Other side 12a Conductor pattern 18 Space 20, 30 Electronic component 40 Mold resin 41 Tapered part 90 Mold

Claims (5)

A substrate (10) having one side (11) and the other side (12) opposite the one side;
Electronic components (20, 30) mounted on one side of the substrate;
A mold resin (40) that is provided on one side of the substrate and seals the electronic component;
At least a portion of the substrate is disposed to the outside of the mold resin;
In the portion where the substrate is disposed to the outside of the mold resin, the mold resin includes a mold resin on a side surface of the mold resin, with one side of the substrate being the lower surface and the opposite side of the lower surface being the upper surface. It protrudes from the lower surface side of the upper surface toward the outside of the mold resin, and is inclined with respect to the one surface, and gradually increases from the one surface toward the outer surface of the mold resin. The electronic device is provided with a tapered portion (41) having a low height.   2. The electronic device according to claim 1, wherein a portion of the side surface of the mold resin that is different from the tapered portion is perpendicular to one surface of the substrate.   The taper portion has an R-shaped curved surface at least one of a boundary position between the taper portion and a portion different from the taper portion of the side surface of the mold resin and a boundary position between the taper portion and one surface of the substrate. The electronic device according to claim 1, wherein the electronic device is provided.   The taper portion is formed from a position lower than a height of one side of the mold resin from which the height of the taper portion is highest among the side surfaces of the mold resin. The electronic device as described in any one. A substrate (10) having one side (11) and the other side (12) opposite the one side;
Electronic components (20, 30) mounted on one side of the substrate;
A mold resin (40) provided on one side of the substrate for sealing the electronic component,
Preparing the substrate and mounting the electronic component on one surface of the substrate;
A second mold (92) having a cavity provided on one surface side of the substrate in a state of being in contact with the first mold (91) on the other surface side of the substrate on which the electronic component is mounted is disposed in the cavity. A step of filling the resin material with the resin material and forming the mold resin by molding by sliding the plunger into the opening of the first mold including the cavity and performing heating and pressurization.
In the step of forming the mold resin, as the second mold, an inner wall surface constituting the cavity of the second mold is tapered so that the cavity gradually spreads toward one surface of the substrate. By using the mold resin, one side of the substrate is the lower surface, and the opposite side of the lower surface is the upper surface, and the mold resin is moved from the position on the lower surface side to the upper surface of the mold on the side surface of the mold. Forming a tapered portion (41) that protrudes outward from the surface and is inclined with respect to the one surface and gradually decreases in height from the one surface toward the outer side of the mold resin. A method for manufacturing an electronic device.

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